Manufacturing method for component embedded substrate

Abstract

This manufacturing method comprises, in the following order: a step for preparing a substrate having a cavity opened on a first surface; a step for attaching a component into the cavity; a step for selectively filling the cavity with a liquid resin composition; a step for curing the liquid resin composition to form a first cured layer in the cavity; a step for laminating a resin composition layer on the first cured layer; and a step for curing the resin composition layer to form a second cured layer, wherein the thickness of the substrate having the cavity opened on the first surface is 1.0 mm or more, and the average linear thermal expansion coefficient of a cured product of the liquid resin composition is less than 20 ppm / °C.

Description

Manufacturing method for component-embedded substrate

[0001] The present invention relates to a method for manufacturing a component-embedded substrate, and a set of a liquid resin composition and a resin sheet that can be used in this manufacturing method.

[0002] In recent years, the demand for small, highly functional electronic devices such as smartphones and tablet PCs has been increasing. Accordingly, there is a demand for substrates used in such small, highly functional electronic devices to have even higher functionality and be smaller in size.

[0003] Components such as bare chips and chip capacitors can be mounted on the substrate. Such components are sometimes embedded in the substrate to meet the demand for higher functionality and smaller size of the substrate. For example, it has been studied to obtain a component-embedded substrate that includes a substrate and components built into the substrate by embedding the components in a cavity formed in the substrate (Patent Document 1).

[0004] JP 2011-216636 A

[0005] A component-embedded substrate can be manufactured, for example, by the following method using a substrate formed with a cavity for accommodating a component. A temporary adhesive material for temporarily attaching the component is provided on one main surface of the substrate with the cavity formed therein. The component is temporarily attached to the surface of the temporary adhesive material exposed through the cavity. A resin composition layer is then laminated over the entire other main surface of the substrate (i.e., the main surface opposite the temporary adhesive material). The resin composition layer is then cured to form an insulating layer, thereby obtaining a component-embedded substrate. In this method, in the step of forming the resin composition layer, a portion of the resin composition layer penetrates into the cavity, thereby embedding the component. Therefore, by curing the resin composition layer, the component can be embedded in the insulating layer obtained by curing the resin composition layer.

[0006] In recent years, in order to manufacture higher performance and highly functional electronic devices, there has been a demand for components formed in cavities with higher functionality. Since highly functional components have a thickness of 600 μm or more, the thickness of the substrate in which the cavity is formed needs to be 1 mm or more in order to embed the components in the cavity.

[0007] However, the present inventors have discovered that when a resin composition layer is filled into a cavity in a substrate having a thickness of 1 mm or more, delamination (interlayer peeling) occurs between the component in the cavity and the insulating layer (the cured product of the resin composition layer).

[0008] Furthermore, in order to fill a cavity in a substrate having a thickness of 1 mm or more with a resin composition layer, a method has been considered in which a liquid resin composition is filled into the cavity from the main surface opposite the temporary bonding material, the cavity is cured, and then a resin composition layer different from the liquid resin composition is laminated over the entire main surface on the opposite side and cured to form an insulating layer. In order to improve the filling ability of the liquid resin composition in the cavity, it is thought that the viscosity of the liquid resin composition can be reduced.

[0009] However, the present inventors have found that if the viscosity of the liquid resin composition is low, the liquid resin composition will seep out to the outer periphery of the cavity. Hereinafter, the phenomenon of the liquid resin seeping out to the outer periphery of the cavity may be referred to as "seepage to the outer periphery of the cavity."

[0010] The present invention was devised in view of the above-mentioned problems, and aims to provide a method for manufacturing a component-embedded substrate that can suppress the occurrence of delamination between the component in the cavity and the insulating layer and the tendency for the component to seep out to the outer periphery of the cavity; a liquid resin composition that can be used in the manufacturing method; and a set that includes a liquid resin composition and a resin sheet that can suppress warping when used in the manufacturing method.

[0011] The present inventors have conducted extensive research to solve the above-mentioned problems, and as a result, have found that the above-mentioned problems can be solved by using a liquid resin composition that is prepared so that the average coefficient of linear thermal expansion (CTE) of the cured product of the liquid resin composition to be selectively filled into the cavity is less than 20 ppm / °C, thereby completing the present invention.

[0012] That is, the present invention includes the following: [1] A method for manufacturing a component-embedded substrate, comprising the steps of: (I) preparing a substrate having a cavity opening to a first surface thereof; (II) attaching a component into the cavity; (III) selectively filling the cavity with a liquid resin composition; (IV) curing the liquid resin composition to form a first cured layer in the cavity; (V) laminating a resin composition layer on the first cured layer; and (VI) curing the resin composition layer to form a second cured layer, in this order, wherein the substrate having a cavity opening to a first surface thereof has a thickness of 1.0 mm or more, and the cured product of the liquid resin composition has an average linear thermal expansion coefficient of less than 20 ppm / °C. [2] The method for manufacturing a component-embedded substrate according to [1], wherein the cured product of the liquid resin composition has an elastic modulus at 25°C of 3.5 GPa or more. [3] The method for manufacturing a component-embedded substrate according to [1] or [2], wherein the step (V) includes: preparing a resin sheet having a support and the resin composition layer formed on the support; and laminating the resin sheet and the first cured layer, and laminating the resin composition layer on the first cured layer. [4] The method for manufacturing a component-embedded substrate according to any of [1] to [3], wherein the substrate prepared in the step (I) has the first surface and a second surface opposite to the first surface, the cavity opens to both the first surface and the second surface, and a temporary bonding material is provided on the second surface. [5] The method for manufacturing a component-embedded substrate according to any of [1] to [3], wherein the average linear thermal expansion coefficient of the cured product of the resin composition layer is α Ｓ The average linear thermal expansion coefficient of the cured product of the liquid resin composition is α Ｌ Then, α Ｓ / α Ｌ [6] The method for manufacturing a component-embedded substrate according to any one of [1] to [4], wherein the modulus of elasticity of the cured product of the resin composition layer at 25°C is E Ｓ The elastic modulus of the cured product of the liquid resin composition at 25°C is E Ｌ When this is done, E Ｓ / E Ｌ

[0023]

[0024] The method for producing a component-embedded substrate according to any one of [1] to [5], wherein the value of (A) is 0.3 or more and less than 2. [7] The method for producing a component-embedded substrate according to any one of [1] to [6], wherein the liquid resin composition contains (A) an inorganic filler. [8] The method for producing a component-embedded substrate according to [7], wherein the average particle size of (A) the inorganic filler is 10 μm or less. [9] The method for producing a component-embedded substrate according to any one of [1] to [8], wherein the viscosity of the liquid resin composition at 25°C is 300 Pa s or less.

[10] The method for producing a component-embedded substrate according to any one of [7] to [9], wherein the liquid resin composition contains (F) a dispersant, and the component (F) contains any one of an alkylene skeleton, a (meth)acrylic skeleton, and a polyallylamine skeleton.

[11] The method for producing a component-embedded substrate according to

[10] , wherein the component (F) has a functional group, and the functional group is any one of a carboxy group and an amino group.

[12] The method for manufacturing a component-embedded substrate according to any one of [1] to

[11] , wherein the resin composition layer contains (a) an inorganic filler.

[13] The method for manufacturing a component-embedded substrate according to

[12] , wherein (a) the inorganic filler has an average particle size of 2 μm or less.

[14] A set comprising a liquid resin composition and a resin sheet having a resin composition layer containing a coating resin composition, wherein the average linear thermal expansion coefficient of a cured product of the coating resin composition is α Ｓ The average linear thermal expansion coefficient of the cured product of the liquid resin composition is α Ｌ Then, α Ｓ / α Ｌ is greater than 0.6 and less than or equal to 7.5.

[0013] According to the present invention, it is possible to provide a method for manufacturing a component-embedded substrate, which can suppress delamination between the component in the cavity and the insulating layer and leakage to the outer periphery of the cavity; a liquid resin composition that can be used in the manufacturing method; and a set including a liquid resin composition and a resin sheet, which can suppress warping when used in the manufacturing method.

[0014] FIG. 1 is a cross-sectional view schematically showing an example of a cavity substrate prepared in step (I) of a manufacturing method according to an embodiment of the present invention. FIG. 2 is a cross-sectional view schematically showing an example of a state in which a component is attached to a cavity of the cavity substrate in step (II) of the manufacturing method according to an embodiment of the present invention. FIG. 3 is a cross-sectional view schematically showing a state in which a mask is placed on a first surface of the cavity substrate in step (III) of the manufacturing method according to an embodiment of the present invention. FIG. 4 is a cross-sectional view schematically showing the cavity substrate and the mask in a first printing step in step (III) of the manufacturing method according to an embodiment of the present invention. FIG. 5 is a cross-sectional view schematically showing the cavity substrate and the mask in a second printing step in step (III) of the manufacturing method according to an embodiment of the present invention. FIG. 6 is a cross-sectional view schematically showing a state in which a liquid resin composition is filled into a cavity of the cavity substrate in step (III) of the manufacturing method according to an embodiment of the present invention. FIG. 7 is a cross-sectional view schematically showing an example of a state in which the liquid resin composition filled into the cavity is cured in step (IV) of the manufacturing method according to an embodiment of the present invention. Fig. 8 is a cross-sectional view schematically showing a state in which a resin sheet is laminated on the first cured layer in step (V) of a manufacturing method according to one embodiment of the present invention. Fig. 9 is a cross-sectional view schematically showing a state in which a resin sheet is laminated on the first cured layer in step (V) of a manufacturing method according to one embodiment of the present invention. Fig. 10 is a cross-sectional view schematically showing a component-embedded substrate obtained by curing the coated resin composition layer in step (V) of a manufacturing method according to one embodiment of the present invention. Fig. 11 is a schematic plan view showing a cavity substrate as viewed from the thickness direction to explain the position of the cavity formed in Example 1 of the present invention.

[0015] The present invention will be described in detail below with reference to embodiments and examples. However, the present invention is not limited to the following embodiments and examples, and may be modified and implemented as desired within the scope of the claims and their equivalents.

[0016] [Method for manufacturing component-embedded substrate] A method for manufacturing a component-embedded substrate according to one embodiment of the present invention includes, in this order: step (I) of preparing a substrate having a cavity formed therein; step (II) of attaching a component into the cavity; step (III) of selectively filling the cavity with a liquid resin composition; step (IV) of curing the liquid resin composition to form a first cured layer in the cavity; step (V) of forming a resin composition layer on the first cured layer; and step (VI) of curing the resin composition layer to form a second cured layer.

[0017] In an embodiment of the present invention, the substrate having the cavity opening to the first surface formed therein has a thickness of 1.0 mm or more.

[0018] In the following description, the substrate having a cavity formed therein and prepared in step (I) may be referred to as a "cavity substrate." Also, in the following description, the layer of the liquid resin composition formed in the cavity by the liquid resin composition filled in step (III) may be referred to as a "liquid resin composition layer." Furthermore, in the following description, the resin composition layer formed in step (V) may be referred to as a "coating resin composition layer," and the resin composition contained in the coating resin composition layer may be referred to as a "coating resin composition."

[0019] <Step (I) of Preparing a Cavity Substrate> Figure 1 is a cross-sectional view schematically showing an example of a cavity substrate 10 prepared in step (I) of a manufacturing method according to one embodiment of the present invention. As shown in Figure 1, the cavity substrate 10 prepared in step (I) has, as main surfaces, a first surface 10U and a second surface 10D opposite to the first surface 10U. Furthermore, the cavity substrate 10 has cavities 20 formed as holes that open to at least the first surface 10U.

[0020] Examples of the cavity substrate 10 include a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, and a thermosetting polyphenylene ether substrate, with a glass epoxy substrate being preferred.

[0021] The cavity substrate 10 may include a conductor layer (not shown). This conductor layer may also be patterned. The conductor layer can be used as circuit wiring such as via wiring or surface wiring. A substrate having a conductor layer that has been patterned in this way and can function as circuit wiring is sometimes called a "circuit board." The term "circuit board" also encompasses intermediate products on which further insulating layers and / or conductor layers are to be formed, for example, when manufacturing a semiconductor chip package or a printed wiring board.

[0022] The thickness of the cavity substrate 10 is 1 mm or more, preferably 1.2 mm or more, more preferably 1.3 mm or more, even more preferably 1.4 mm or more, or 1.5 mm or more, in order to fill the cavity with a thick component. The upper limit of the thickness of the cavity substrate 10 is preferably less than 10 mm, more preferably 5 mm or less, even more preferably 3 mm or less, or 2 mm or less, from the viewpoint of thinning the component-embedded substrate.

[0023] The cavity 20 may be open only to the first surface 10U of the cavity substrate 10. Alternatively, the cavity 20 may penetrate the cavity substrate 10 and be open to both the first surface 10U and the second surface 10D. In this embodiment, an example is shown in which the cavity 20 is open to both the first surface 10U and the second surface 10D of the cavity substrate 10.

[0024] Only one cavity 20 may be formed in the cavity substrate 10, or multiple cavities 20 may be formed at intervals. The pitch between the cavities 20 depends on the opening dimensions of the cavity 20 itself, but from the viewpoint of miniaturizing the component-embedded substrate, it is preferably 10 mm or less, more preferably 9 mm or less, even more preferably 8 mm or less, even more preferably 7 mm or less, and particularly preferably 6 mm or less. The lower limit is usually 0.5 mm or more, 1 mm or more, etc. The pitch between the cavities 20 may be the same or different across the cavity substrate 10.

[0025] The dimensions of the cavity 20 are set so that a component (not shown in FIG. 1) can be accommodated in the cavity 20. Specific examples of dimensions include a width of the opening 21 of the cavity 20 of 6 mm to 20 mm. The depth of the cavity 20 may be within the same range as the thickness of the cavity substrate 10 described above. The dimensions of the cavity 20 may be the same or different across the cavity substrate 10.

[0026] The opening shape of the cavity 20 is not particularly limited. The opening shape of the cavity 20 refers to the shape of the opening 21 of the cavity 20 when the cavity substrate 10 is viewed from the thickness direction. Examples of the opening shape of the cavity 20 include a rectangle, a square, a circle, a substantially rectangle, and a substantially circle. The opening shape of the cavity 20 may be the same or different across the cavity substrate 10.

[0027] When the cavity 20 opens on both the first surface 10U and the second surface 10D of the cavity substrate 10, as in the example shown in this embodiment, a temporary adhesive material 30 is preferably provided on the second surface 10D of the cavity substrate 10. This temporary adhesive material 30 is usually provided so as to close the opening 22 of the cavity 20 that opens on the second surface 10D. This makes it easier to attach components to the cavity 20 and prevents leakage of the liquid resin composition (not shown in FIG. 1 ) filled in the cavity 20.

[0028] The temporary adhesive material 30 may be, for example, a film-like material. Furthermore, from the viewpoint of stably attaching the component within the cavity 20, the temporary adhesive material 30 preferably has an adhesive surface 30U that is sufficiently adhesive to attach the component. A commercially available product may be used as such a temporary adhesive material 30. Examples of commercially available temporary adhesive materials 30 include "PFDKE-1525TT" (polyimide film with adhesive) manufactured by Arisawa Manufacturing Co., Ltd. and the UC series (UV tape for wafer dicing) manufactured by Furukawa Electric Co., Ltd. In this embodiment, an example is shown in which a film-like temporary adhesive material 30 having an adhesive surface 30U is provided on the second surface 10D of the cavity substrate 10.

[0029] The cavity substrate 10 can be manufactured by a method including forming the cavity 20 in the substrate 10 before the cavity is formed. The cavity 20 can be formed by a method using, for example, a drill, a laser, plasma, or an etching medium, taking into consideration the characteristics of the substrate 10. Furthermore, when a temporary adhesive material 30 is provided on the second surface 10D as in the example shown in this embodiment, the temporary adhesive material 30 may be provided before or after the cavity 20 is formed.

[0030] <Step (II) of Mounting a Component in a Cavity> Fig. 2 is a cross-sectional view schematically illustrating an example of a state in which a component 40 is mounted in the cavity 20 of the cavity substrate 10 in step (II) of the manufacturing method according to one embodiment of the present invention. As shown in Fig. 2, after step (I), step (II) of mounting the component 40 in the cavity 20 of the cavity substrate 10 is performed.

[0031] Typically, the component 40 is placed in the cavity 20 through the opening 21 opened in the first surface 10U, and the component 40 is attached to the bottom of the cavity 20. When a temporary adhesive material 30 having an adhesive surface 30U is provided as in the example shown in this embodiment, the component 40 can be attached to the adhesive surface 30U of the temporary adhesive material 30 exposed through the cavity 20.

[0032] Generally, an appropriate electronic component is selected as the component 40 depending on the desired characteristics. Examples of the component 40 include passive components such as capacitors, inductors, and resistors; active components such as semiconductor chips; etc. The same component 40 may be attached to all cavities 20, or different components 40 may be attached to each cavity 20.

[0033] The thickness (height) of the component 40 is 600 μm or more, preferably 620 μm or more, more preferably 630 μm or more, even more preferably 650 μm or more, and preferably 1200 μm or less, more preferably 1000 μm or less, even more preferably 900 μm or less, or 800 μm or less.

[0034] <Step (III) of filling the cavity with the liquid resin composition> After step (II), step (III) is performed in which the liquid resin composition is selectively filled into the cavity 20. By filling the cavity 20 with the liquid resin composition, the part 40 is embedded in the liquid resin composition. In addition, a liquid resin composition layer is formed in the cavity 20 by the liquid resin composition.

[0035] "Selectively" filling the cavity 20 with the liquid resin composition means filling the cavity 20 with the liquid resin composition so that the liquid resin composition does not adhere to at least a portion of the non-opening portion 11U (see FIGS. 3 and 4) of the first surface 10U of the cavity substrate 10. The non-opening portion 11U of the first surface 10U refers to the portion of the first surface 10U other than the opening 21. The cavity 20 is usually filled with the liquid resin composition so that the liquid resin composition does not adhere to some or all of the non-opening portion 11U, and preferably so that the liquid resin composition does not adhere to all of the non-opening portion 11U.

[0036] The method for filling the cavity 20 with the liquid resin composition is not particularly limited. Filling can be performed using, for example, a dispenser. In the method using a dispenser, the liquid resin composition is typically filled into a syringe equipped with a nozzle, and the syringe is attached to the dispenser. The liquid resin composition in the syringe is then discharged by the dispenser through the nozzle into the cavity 20, thereby filling the cavity 20 with the liquid resin composition.

[0037] From the viewpoint of efficiently filling the cavity 20 with the liquid resin composition, it is preferable to perform the filling by a printing method using a mask. An example of this method will be described below with reference to the drawings.

[0038] 3 is a cross-sectional view schematically illustrating a state in which a mask 50 is placed on the first surface 10U of the cavity substrate 10, in order to outline step (III) of a manufacturing method according to one embodiment of the present invention. As shown in Fig. 3, the mask 50 is placed on the first surface 10U of the cavity substrate 10. The mask 50 has holes 51 formed therethrough in the thickness direction at positions corresponding to the cavities 20. Therefore, the non-opening portion 11U of the first surface 10U of the cavity substrate 10 is covered by the mask 50, and the cavities 20 communicate with the outside through the holes 51.

[0039] Therefore, by supplying the liquid resin composition to the cavity 20 through the hole 51, the liquid resin composition can be selectively filled into the cavity 20. For example, a liquid resin composition 60 is placed on the mask 50, and the liquid resin composition 60 is swept by the squeegee 52. Specifically, while maintaining the squeegee 52 in contact with the mask 50, the squeegee 52 is moved along the surface of the mask 50 as shown by arrow A3. As the squeegee 52 moves, the liquid resin composition 60 pushed by the squeegee 52 moves along the surface of the mask 50. As the squeegee 52 moves across the hole 51, the liquid resin composition 60 enters the cavity 20 through the hole 51 and can fill the cavity 20. Typically, the mask 50 is removed after the cavity 20 is filled with the liquid resin composition 60.

[0040] Step (III) preferably includes a first printing step in which a first squeegee is moved relatively along the surface of the mask to fill the cavities with a liquid resin composition, and a second printing step in which a second squeegee, which is the same as or different from the first squeegee, is moved relatively along the surface of the mask to apply the liquid resin composition.

[0041] In the first printing step, the first squeegee is moved relative to the substrate and the mask so that a portion of the first squeegee is pressed into the hole (the opening of the cavity substrate). This makes it easy to fill the liquid resin composition all the way to the bottom of the cavity, achieving good filling properties.

[0042] Furthermore, in the second printing step, a second squeegee is used to apply the liquid resin composition onto the liquid resin composition filled in the cavity. Since the liquid resin composition is filled into the cavity in the first printing step, a liquid resin composition layer is formed in the cavity. However, depressions may be formed on the surface of the liquid resin composition layer at the entrance of the cavity. In contrast, since the liquid resin composition is applied onto the liquid resin composition layer filled in the cavity in the second printing step, the depressions can be filled with the liquid resin composition. Therefore, depressions can be suppressed.

[0043] 4 is a cross-sectional view schematically illustrating a state in which a mask 50 is placed on the first surface 10U of the cavity substrate 10 in the first printing step. As shown in FIG. 4, in the first printing step, the first squeegee 521 is positioned so that the liquid resin composition 60 is located between the first squeegee 521 and the opening 21. At this time, from the viewpoint of selectively filling the cavity 20 with the liquid resin composition 60, the first squeegee 521 is positioned at a predetermined attack angle θ between the surface 50U of the mask 50 and the first squeegee 521. １ The angle of attack θ can be set to be in contact with the surface 50U in a tilted state. １ represents the angle between the first squeegee 521 and the surface 50U of the mask 50, in the forward direction of the arrow A4, which is the movement direction. The tip of the first squeegee 521 may bend due to friction with the mask 50. In this case, the attack angle θ １ represents the angle formed between the portion of the first squeegee 521 other than the bent tip and the surface 50U of the mask 50. The first squeegee 521 can be positioned in a state where it is pressed against the mask 50 with a predetermined printing pressure. Here, the printing pressure of the first squeegee 521 represents the pressure with which the first squeegee 521 is pressed against the mask 50.

[0044] The first squeegee 521 has an attack angle θ １With the printing pressure maintained, the first squeegee 521 is moved on the surface 50U of the mask 50 along the surface 50U as shown by arrow A4 while maintaining contact with the mask 50. To achieve this movement, the first squeegee 521 may be moved, the cavity substrate 10 may be moved, or all of these may be moved. In this embodiment, an example in which the first squeegee 521 is moved will be described.

[0045] The first squeegee 521 is moved so that the first squeegee 521 crosses the hole 51 in the mask 50. The liquid resin composition 60 is pushed by the moving first squeegee 521, and therefore the liquid resin composition 60 also moves along the arrow A4. Then, as the first squeegee 521 crosses the hole 51, the liquid resin composition is filled into the cavity 20 in the cavity substrate 10 through the opening 21.

[0046] The first squeegee 521 is moved in the first printing step so that a portion of the first squeegee 521 is pressed into the hole 51. One method for pressing a portion of the first squeegee 521 into the hole 51 is to use a highly flexible squeegee as the first squeegee 521. A highly flexible squeegee can deform when subjected to an appropriate printing pressure, and can be pressed into the hole 51. In this case, a highly flexible material is usually used as the material for the first squeegee 521. An elastic material with a low elastic modulus is preferred as a highly flexible material. An example of such an elastic material is rubber, and therefore a rubber squeegee is preferred as the first squeegee 521.

[0047] The rubber hardness of the elastic material can be set arbitrarily within a range that allows a portion of the first squeegee 521 to be pressed into the hole 51. As a specific example of a range, the rubber hardness is preferably 50 degrees or more and preferably 100 degrees or less. The rubber hardness can be measured using a durometer (type A) under the same temperature conditions as those in the first printing process.

[0048] Another method for forcing a portion of the first squeegee 521 into the hole 51 is, for example, to increase the printing pressure and the amount of pressing of the first squeegee 521. When the printing pressure of the first squeegee 521 is large, the first squeegee 521 can easily deform to conform to the shape of the mask 50, and therefore can be pressed into the hole 51.

[0049] The printing pressure of the first squeegee 521 can be set arbitrarily within the range that allows a portion of the first squeegee 521 to be pushed into the hole 51, and is preferably 100 N or more, more preferably 200 N or more, and even more preferably 300 N or more, and is preferably 1000 N or less, more preferably 800 N or less, and even more preferably 600 N or less.

[0050] The pushing amount of the first squeegee 521 can be set arbitrarily within the range in which a portion of the first squeegee 521 can be pushed into the hole 51, and is preferably 0.1 mm or more, more preferably 0.5 mm or more, and even more preferably 1 mm or more, and is preferably 10 mm or less, more preferably 8 mm or less, and even more preferably 5 mm or less.

[0051] As another method for forcing a part of the first squeegee 521 into the hole 51, for example, the attack angle θ １ The attack angle θ of the first squeegee 521 can be reduced. １ If the stress is small, the first squeegee 521 is easily deformed by receiving a large stress in the thickness direction of the first squeegee 521 , and can be pushed into the hole 51 .

[0052] Attack angle θ of the first squeegee 521 １ can be set arbitrarily within the range that allows a portion of the first squeegee 521 to be pushed into the hole 51, and is preferably 1° or more, more preferably 3° or more, and particularly preferably 5° or more, and is preferably 90° or less, more preferably 45° or less, and particularly preferably 20° or less.

[0053] Another method for forcing a portion of the first squeegee 521 into the hole 51 is, for example, to slow down the relative movement speed of the first squeegee 521 with respect to the mask 50. Hereinafter, the relative movement speed may be referred to as the "printing speed" as appropriate. If the printing speed of the first squeegee 521 is slow, the resistance of the liquid resin composition can be reduced, and the first squeegee 521 can be forced into the hole 51 without being obstructed by the liquid resin composition.

[0054] The printing speed of the first squeegee 521 can be set arbitrarily within the range in which a portion of the first squeegee 521 can be pushed into the hole 51, and is preferably 1 mm / sec or more, more preferably 2 mm / sec or more, and particularly preferably 3 mm / sec or more, and is preferably 50 mm / sec or less, more preferably 40 mm / sec or less, and particularly preferably 30 mm / sec or less.

[0055] The above-mentioned methods exemplified as methods for forcing a part of the first squeegee 521 into the interior of the hole 51 may be carried out in any combination.

[0056] The first printing step may be carried out only once, or may be carried out two or more times under the same or different conditions.

[0057] After the first printing step, a liquid resin composition layer 61 is formed in the cavity 20 by the liquid resin composition 60, and a depression 62 may be formed in the liquid resin composition layer 61 (see FIG. 5 ). This depression 62 may be formed, for example, when the first squeegee 521 excessively pushes the liquid resin composition 60 into the cavity 20, or when part of the liquid resin composition 60 is scraped off by the first squeegee 521. Therefore, the second printing step is usually performed after the first printing step.

[0058] 5 is a cross-sectional view schematically illustrating the state in which a mask 50 is placed on the first surface 10U of the cavity substrate 10 in the second printing step. As shown in Fig. 5, after the first printing step, a second squeegee 522 is moved relatively along the surface 50U of the mask 50 to apply the liquid resin composition 60 onto the liquid resin composition layer 61 filled in the cavity 20 in the second printing step.

[0059] The second squeegee 522 may be the same as the first squeegee 521, or may be different from the first squeegee 521. The movement direction of the second squeegee 522 may be the same as or different from the movement direction of the first squeegee 521.

[0060] In the second printing step, the second squeegee 522 is disposed near the end of the mask 50 so that the liquid resin composition 60 is positioned between the second squeegee 522 and the opening 21. At this time, in order to achieve appropriate application of the liquid resin composition, the second squeegee 522 is positioned at a predetermined attack angle θ between the second squeegee 522 and the surface 50U of the mask 50. ２ The angle of attack θ can be set to be in contact with the surface 50U in a tilted state. ２ represents the angle that the second squeegee 522 makes with the surface 50U of the mask 50 in the direction of the arrow A5. The tip of the second squeegee 522 may bend due to friction with the mask 50 or the liquid resin composition 60. In this case, the attack angle θ ２ represents the angle formed between the portion of the second squeegee 522 other than the bent tip and the surface 50U of the mask 50. The second squeegee 522 can be positioned in a state where it is pressed against the mask 50 with a predetermined printing pressure. Here, the printing pressure of the second squeegee 522 represents the pressure with which the second squeegee 522 is pressed against the mask 50.

[0061] The second squeegee 522 has the attack angle θ ２ While maintaining the printing pressure, the second squeegee 522 is moved relatively on the surface 50U of the mask 50 along the surface 50U in the direction of arrow A5. To achieve the relative movement, the second squeegee 522 may be moved, the cavity substrate 10 may be moved, or all of these may be moved. In this embodiment, an example in which the second squeegee 522 is moved will be described.

[0062] The second squeegee 522 is moved so that it crosses the hole 51. The liquid resin composition 60 is pushed by the moving second squeegee 522, so that the liquid resin composition 60 also moves in the direction of arrow A5. Then, as the second squeegee 522 crosses the hole 51, more of the liquid resin composition 60 is applied onto the liquid resin composition layer 61 in the cavity 20 through the opening 21. This fills the depression 62, making it possible to make the depression 62 smaller, or preferably eliminate the depression.

[0063] It is preferable that the second squeegee 522 is moved in the second printing step so as to eliminate the depressions 62. Eliminating the depressions 62 can be achieved by various methods.

[0064] One method for eliminating the depressions 62 is to use a squeegee with low flexibility as the second squeegee 522. A squeegee with low flexibility is less likely to deform even when subjected to pressure, and is therefore less likely to enter the holes 51, thereby making it possible to eliminate the depressions 62. Specifically, it is preferable to use a second squeegee 522 that has a higher elastic modulus than the first squeegee 521. In this case, a material with a high elastic modulus is typically used for the second squeegee 522. A material with a high elastic modulus is preferably a rigid material that has a higher elastic modulus than the elastic material of the first squeegee 521, and examples of such materials include metal materials such as SUS. Therefore, a metal squeegee is preferred for the second squeegee 522.

[0065] One method for eliminating the depressions 62 is to reduce the printing pressure and the amount of pressing of the second squeegee 522. If the printing pressure of the second squeegee 522 is small, the deformation of the second squeegee 522 can be reduced, and therefore, the second squeegee 522 can be prevented from being pressed into the hole 51. Therefore, it is preferable that the printing pressure of the second squeegee 522 is smaller than the printing pressure of the first squeegee 521.

[0066] The printing pressure of the second squeegee 522 can be set arbitrarily within the range that can eliminate the depressions 62, and is preferably 500 N or less, more preferably 400 N or less, even more preferably 300 N or less, and is preferably 50 N or more, more preferably 80 N or more, even more preferably 100 N or more.

[0067] The amount of depression of the second squeegee 522 can be set arbitrarily within the range that can eliminate the depression 62, and is preferably 5 mm or less, more preferably 3 mm or less, and even more preferably 1 mm or less, and is preferably 0.05 mm or more, more preferably 0.1 mm or more, and even more preferably 0.3 mm or more.

[0068] As another method for eliminating the recess 62, for example, the attack angle θ of the second squeegee 522 is ２ The attack angle θ of the second squeegee 522 can be increased. ２ When the stress is large, the second squeegee 522 receives only a small stress in the thickness direction of the second squeegee 522, thereby reducing deformation. Therefore, the second squeegee 522 is prevented from entering the opening 210 of the mask 50, and the depression 62 can be eliminated.

[0069] Attack angle θ of the second squeegee 522 ２ can be set arbitrarily within a range in which the depressions 62 can be eliminated. For example, the attack angle θ １ It is preferable that the attack angle θ is greater than ２ As an example of a specific range of attack angle θ ２ is preferably 10° or more, more preferably 30° or more, particularly preferably 45° or more, and is preferably 90° or less, more preferably 85° or less, particularly preferably 80° or less.

[0070] Another method for eliminating the depressions 62 is, for example, to increase the printing speed, which is the relative movement speed of the second squeegee 522 with respect to the mask 50. When the printing speed of the second squeegee 522 is high, the resistance of the liquid resin composition can be increased, and therefore, the second squeegee 522 can be prevented from entering the inside of the hole 51, making it possible to eliminate the depressions 62.

[0071] The printing speed of the second squeegee 522 can be set arbitrarily within the range that can eliminate the depressions 62, and is preferably 1 mm / sec or more, more preferably 5 mm / sec or more, and particularly preferably 10 mm / sec or more, and is preferably 100 mm / sec or less, more preferably 80 mm / sec or less, and particularly preferably 70 mm / sec or less.

[0072] Furthermore, the printing speed of the second squeegee 522 in the second printing step is preferably faster than the printing speed of the first squeegee 421 in the first printing step. In this case, the difference between the printing speed of the first squeegee 521 and the printing speed of the second squeegee 522 is preferably 0 mm / sec or more, more preferably 10 mm / sec or more, and particularly preferably 20 mm / sec or more. There is no particular upper limit, and it can be, for example, 100 mm / sec or less.

[0073] The second printing step may be carried out only once, or may be carried out two or more times under the same or different conditions.

[0074] Step (III) may include a step of supplying the liquid resin composition 60 onto the mask 50 at one or more of the following times: during the first printing step, between the first printing step and the second printing step, and during the second printing step. The first and second printing steps may also be performed in a reduced pressure environment. The degree of vacuum in the reduced pressure environment is preferably 500 Pa or less, more preferably 300 Pa or less, and even more preferably 200 Pa or less, or 150 Pa or less. The lower limit is ideally 0 Pa or more, but is usually 0.1 Pa or more. When lamination is performed at such a high level of vacuum, the generation of voids can be suppressed.

[0075] While the printing method using a mask has been described above, the printing method may also be performed using, for example, a semi-automatic vacuum hole filling device equipped with a CCD camera. An example of a semi-automatic vacuum hole filling device equipped with a CCD camera is the "SVM-6151IP" manufactured by Seria Corporation. The positioning of the holes may also be performed using the semi-automatic vacuum hole filling device equipped with a CCD camera.

[0076] FIG. 6 is a cross-sectional view schematically illustrating the state in which the cavity 20 of the cavity substrate 10 is filled with a liquid resin composition 60 in step (III) of a manufacturing method according to one embodiment of the present invention. As shown in FIG. 6 , when the cavity 20 is filled with the liquid resin composition 60, a liquid resin composition layer 61 is formed by the liquid resin composition 60 within the cavity 20. The component 40 is embedded within this liquid resin composition layer 61. Because the liquid resin composition 60 has excellent fluidity, the liquid resin composition 60 can smoothly penetrate every corner of the cavity 20. Furthermore, the liquid resin composition 60 is prevented from seeping out to the periphery of the cavity. Therefore, the cavity 20 is filled with the component 40 and the liquid resin composition 60, preventing the formation of unfilled portions and preventing the liquid resin composition 60 from seeping out to the periphery of the cavity. Furthermore, when the cavity 20 is selectively filled with the liquid resin composition 60, the amount of liquid resin composition 60 that prevents the air from escaping from the cavity 20 can be reduced. Furthermore, unlike the conventional method of embedding the component 40 in the cavity 20 by laminating a resin sheet, when the liquid resin composition 60 is used, there is no component that prevents the air from escaping, such as a support for the resin sheet. Therefore, the air in the cavity 20 can be smoothly escaping from the cavity 20. Therefore, the formation of voids in the liquid resin composition layer 61 can be suppressed. This effect is in stark contrast to the tendency for voids to form in conventional manufacturing methods in which cavities are filled using a resin sheet with a support that includes a metal foil, which is particularly prone to preventing gas permeation.

[0077] <Step (IV) of Curing the Liquid Resin Composition> Figure 7 is a cross-sectional view schematically illustrating an example of the state in which the liquid resin composition filled in the cavity 20 is cured in step (IV) of the manufacturing method according to one embodiment of the present invention. As shown in Figure 7, after step (III), step (IV) is performed to cure the liquid resin composition 60 in the cavity 20. By this step (IV), a first cured layer 70 is formed in the cavity 20 by the cured product of the liquid resin composition 60. Therefore, an intermediate substrate 100 is obtained as an intermediate product including the cavity substrate 10, the component 40, and the first cured layer 70. The first cured layer 70 can usually function as an insulating layer in the cavity 20.

[0078] The liquid resin composition 60 can be cured by an appropriate method depending on the composition of the liquid resin composition 60. For example, when a thermosetting liquid resin composition 60 is used, the liquid resin composition 60 can be cured by heating.

[0079] The thermal curing conditions for the liquid resin composition 60 may vary depending on the composition of the liquid resin composition 60, but the curing temperature is preferably in the range of 120°C to 240°C (more preferably in the range of 150°C to 210°C, and particularly preferably in the range of 160°C to 190°C), and the curing time is preferably in the range of 5 minutes to 180 minutes (more preferably in the range of 10 minutes to 150 minutes, and particularly preferably in the range of 15 minutes to 120 minutes).

[0080] Before thermal curing, the liquid resin composition 60 may be preheated at a temperature lower than the curing temperature. For example, prior to thermal curing, the liquid resin composition 60 may be preheated at a temperature of 50° C. or higher and lower than 120° C. (preferably 60° C. or higher and 110° C. or lower, more preferably 70° C. or higher and 100° C. or lower) for 5 minutes or longer (preferably 5 to 150 minutes, more preferably 15 to 120 minutes).

[0081] If the liquid resin composition 60 contains a volatile component such as a solvent, the volatile component may vaporize when heated. However, the cavity 20 is selectively filled with the liquid resin composition 60, and there is no or little liquid resin composition 60 outside the cavity 20. Therefore, the volatile component contained in the liquid resin composition 60 in the cavity 20 travels a short distance before being released into the air outside the cavity 20, and the volatile component can be smoothly discharged outside the cavity 20. Therefore, the formation of voids in the liquid resin composition layer 61 can be suppressed.

[0082] <Step (V) of Forming a Coating Resin Composition Layer> After step (IV), step (V) is performed to laminate a coating resin composition layer on the first cured layer 70. Typically, in this step (V), the coating resin composition layer is laminated over a wide area of ​​the surface of the intermediate substrate 100, including the non-opening portion 11U, so that the coating resin composition layer is laminated not only on the first cured layer 70 but also on the non-opening portion 11U of the first surface 10U of the cavity substrate 10. Therefore, by curing the coating resin composition layer in step (VI), which will be described later, a second cured layer can be formed not only on the first cured layer 70 but also on the first surface 10U of the cavity substrate 10, including the non-opening portion 11U.

[0083] Fig. 8 is a cross-sectional view schematically showing a state in which a resin sheet 80 is laminated on the first cured layer 70 in step (V) of the manufacturing method according to one embodiment of the present invention. Fig. 8 is also a cross-sectional view schematically showing a state in which the resin sheet 80 is laminated on the first cured layer 70 in step (V) of the manufacturing method according to one embodiment of the present invention.

[0084] As shown in FIG. 8 , the coating resin composition layer 81 is typically formed using a resin sheet 80. The resin sheet 80 includes a support 82 and a coating resin composition layer 81 formed on the support 82. Thus, step (V) typically includes preparing the resin sheet 80, laminating the resin sheet 80 and the first cured layer 70, and laminating the coating resin composition layer 81 on the first cured layer 70. The resin sheet 80 and the first cured layer 70 can be laminated such that the surface of the resin sheet 80 facing the coating resin composition layer 81 faces the first cured layer 70. This lamination typically allows the first cured layer 70 and the coating resin composition layer 81 of the resin sheet 80 to be bonded together. For example, when the entire top surface of the first cured layer 70 in the figure (i.e., the surface on the same side as the first surface 10U of the cavity substrate 10) is exposed, the entire top surface of the first cured layer 70 can be bonded to the coating resin composition layer 81. Furthermore, for example, when a portion of the upper surface of the first cured layer 70 is covered with a conductor layer (not shown) such as wiring, the portion of the upper surface of the first cured layer 70 that is not covered with the conductor layer can be bonded to the coating resin composition layer 81. According to this step (V), it is possible to achieve lamination of the coating resin composition layer 81 on the first cured layer 70, as shown in FIG.

[0085] The lamination method is not particularly limited. For example, lamination may be performed by a vacuum lamination method using a vacuum laminating device. In the vacuum lamination method, lamination can be achieved, for example, by thermocompression bonding the coating resin composition layer 81 onto the intermediate substrate 100 including the first cured layer 70 from the support 82 side under reduced pressure. The thermocompression temperature is preferably in the range of 60°C to 160°C, more preferably 80°C to 140°C. The thermocompression pressure is preferably in the range of 0.098 MPa to 1.77 MPa, more preferably 0.29 MPa to 1.47 MPa. The thermocompression time is preferably in the range of 20 seconds to 400 seconds, more preferably 30 seconds to 300 seconds. Lamination is preferably performed under reduced pressure conditions of 13 hPa or less.

[0086] The lamination may be performed by a vacuum press method. In the vacuum press method, the intermediate substrate 100 and the resin sheet 80 are typically set in a vacuum press device so that the first cured layer 70 and the coating resin composition layer 81 are bonded together. The intermediate substrate 100 and the resin sheet 80 are preferably set in the vacuum press device via cushion paper, a metal plate such as a stainless steel plate (SUS plate), a release film, or the like. Next, a vacuum press treatment is performed under reduced pressure conditions to heat and press-bond the intermediate substrate 100 including the first cured layer 70 and the coating resin composition layer 81 together. The vacuum press treatment is preferably a vacuum heat press treatment (vacuum hot press treatment) in which heat is applied.

[0087] In the vacuum press treatment, the pressure (pressing force) is preferably 0.49 MPa or more, more preferably 0.98 MPa or more, and is preferably 7.9 MPa or less, more preferably 5.9 MPa or less.

[0088] In the vacuum press process, the atmospheric pressure (i.e., the pressure (degree of vacuum) when decompressed in the chamber in which the intermediate substrate 100 and the resin sheet 80 to be processed are stored) is preferably 3×10 －２ MPa or less, more preferably 1 × 10 －２ The lower limit is not particularly limited, but is 1 × 10 －１０ MPa or more.

[0089] In the vacuum press treatment, the heating temperature may vary depending on the composition of the coating resin composition layer 81, but is usually 110°C or higher, preferably 150°C or higher, more preferably 160°C or higher, and particularly preferably 170°C or higher, or 180°C or higher. The upper limit of the heating temperature is not particularly limited, but may be, for example, 240°C or lower. The vacuum press treatment may be performed while increasing the temperature stepwise or continuously, while decreasing the temperature stepwise or continuously, or by combining temperature increases and decreases. Furthermore, as will be described in step (VI) below, the coating resin composition layer 81 may be cured by heating in the vacuum press treatment.

[0090] In the vacuum press treatment, the pressing time is preferably 5 minutes or more, more preferably 10 minutes or more, and even more preferably 15 minutes or more. The upper limit is not particularly limited, but is preferably 300 minutes or less, more preferably 200 minutes or less, and even more preferably 150 minutes or less.

[0091] The vacuum press treatment can be performed using, for example, a vacuum press device that presses intermediate substrate 100 and resin sheet 80 from both sides using a heated metal plate such as a SUS plate. An example of a commercially available vacuum press device is "VH1-1603" manufactured by Kitagawa Seiki Co., Ltd.

[0092] The vacuum pressing treatment may be carried out only once or may be repeated two or more times. When the vacuum pressing treatment is carried out two or more times, the treatment conditions such as the pressure, heating temperature, pressing time, etc. may be the same or different.

[0093] <Step (VI) of Curing the Coating Resin Composition Layer> FIG. 10 is a cross-sectional view schematically illustrating a component-embedded substrate 200 obtained by curing the coating resin composition layer 81 in step (VI) of a manufacturing method according to one embodiment of the present invention. As shown in FIG. 10 , step (VI) of curing the coating resin composition layer 81 is performed after step (V). By curing the coating resin composition layer 81, a second cured layer 90 is formed by the cured product of the coating resin composition. Therefore, a component-embedded substrate 200 can be obtained, which includes a cavity substrate 10, a component 40 disposed in the cavity 20, a first cured layer 70 that embeds the component 40, and a second cured layer 90 formed on the first cured layer 70. Typically, the second cured layer 90 can function as an insulating layer outside the cavity 20. Therefore, this manufacturing method makes it possible to form an insulating layer including the first cured layer 70 and the second cured layer 90.

[0094] The coating resin composition layer 81 can be cured by an appropriate method depending on the composition of the coating resin composition contained in the coating resin composition layer 81. For example, when a thermosetting coating resin composition is used, the coating resin composition layer 81 can be cured by heating. As a specific example, when lamination is performed using a vacuum hot press process in step (V), the coating resin composition layer 81 may be thermally cured using the heat generated during pressing.

[0095] The heat curing conditions for the coating resin composition layer 81 may vary depending on the composition of the coating resin composition, but the curing temperature is preferably 120°C to 240°C (more preferably 150°C to 220°C, and particularly preferably 170°C to 210°C). The curing time may be preferably 5 minutes to 120 minutes (more preferably 10 minutes to 100 minutes, and even more preferably 15 minutes to 100 minutes).

[0096] Before curing the coating resin composition layer 81, the coating resin composition layer 81 may be preheated at a temperature lower than the curing temperature. For example, prior to thermal curing, the coating resin composition layer 81 may be preheated at a temperature of 50° C. or higher and lower than 200° C. (preferably 60° C. or higher and 180° C. or lower, more preferably 70° C. or higher and 150° C. or lower) for 5 minutes or longer (preferably 5 to 150 minutes, more preferably 15 to 120 minutes, and even more preferably 15 to 100 minutes).

[0097] <Optional Step> The method for manufacturing a component-embedded substrate according to this embodiment may further include an optional step in combination with the steps described above. For example, the method for manufacturing a component-embedded substrate may include a step of peeling off the temporary bonding material after step (IV). Furthermore, for example, the method for manufacturing a component-embedded substrate may include a step of peeling off the support after step (V). The support may be peeled off before step (VI) or after step (VI). Furthermore, when the support includes a metal foil, the support may not be peeled off and may be used to form a conductor layer as described below.

[0098] For example, the method for manufacturing a component-embedded substrate may include a step of forming a conductor layer on the second cured layer. There are no limitations on the method for forming this conductor layer. For example, when a resin sheet with a support containing metal foil is used in step (V), the conductor layer as a circuit may be formed by a subtractive method or a modified semi-additive method using the metal foil.

[0099] In the subtractive method, a circuit is usually formed by selectively removing unnecessary portions of the metal foil (non-circuit forming portions) by a removal method such as etching. The circuit formation by the subtractive method can be carried out, for example, by a method including, in this order: i) providing an etching resist on the surface of the metal foil (i.e., the surface opposite to the surface bonded to the second cured layer), ii) exposing and developing the etching resist to form a wiring pattern, iii) etching and removing the exposed metal foil portions, and iv) removing the etching resist.

[0100] In the modified semi-additive process, non-circuit forming portions of a metal foil are typically protected with a plating resist, and a thick layer of a metal such as copper is applied to the circuit forming portions by electrolytic plating. The plating resist is then removed, and the metal foil other than the circuit forming portions is removed by etching to form a circuit. Circuit formation using the modified semi-additive process can be carried out, for example, by a method comprising the following steps in this order: i) providing a plating resist on the surface of the metal foil (i.e., the surface opposite to the surface bonded to the second cured layer); ii) exposing and developing the plating resist to form a wiring pattern; iii) electroplating via the plating resist; iv) removing the plating resist; and v) etching and removing the metal foil other than the circuit forming portions. If the metal foil is thick, before step i), the entire surface of the metal foil may be thinned by a removal method such as etching so that the metal foil has the desired thickness (usually 5 μm or less, 4 μm or less, or 3 μm or less).

[0101] The conductor layer may be formed without using a metal foil. Examples of methods for forming such a conductor layer include plating, sputtering, and vapor deposition. For example, a conductor layer having a desired wiring pattern may be formed by plating the surface of the second cured layer by an appropriate method such as a semi-additive method or a full-additive method.

[0102] For example, the manufacturing method for a component-embedded substrate may include a step of drilling holes in the first and second hardened layers. This step allows holes such as via holes and through holes to be formed in the first and second hardened layers. Specifically, when holes are formed in the first and second hardened layers, extending from the surface of the second hardened layer to the components, a conductive layer on the second hardened layer can be formed in the holes to electrically connect the components to the conductive layer on the second hardened layer. This allows for interlayer connection through the holes. As another specific example, when holes are formed in the second hardened layer, extending from the surface of the second hardened layer to the circuit wiring of the substrate, a conductive layer can be formed in the holes to electrically connect the conductive layer on the second hardened layer to the circuit wiring of the substrate. This allows for interlayer connection through the holes. Examples of methods for forming holes include laser irradiation, etching, and mechanical drilling. The dimensions and shape of the holes can be determined appropriately depending on the design of the component-embedded substrate.

[0103] For example, in the method for manufacturing a component-embedded substrate, after forming a hole, a step of removing smears from the hole may be performed. This step is sometimes called a desmear step. For example, when a conductive layer is formed on the second hardened layer by a plating step, a wet desmear treatment may be performed on the hole. Furthermore, when a conductive layer is formed on the second hardened layer by a sputtering step, a dry desmear process such as a plasma treatment process may be performed. Furthermore, the second hardened layer may be roughened by the desmear step.

[0104] For example, in the method for manufacturing a component-embedded substrate, the second hardened layer may be subjected to a roughening treatment before forming a conductor layer on the second hardened layer. This roughening treatment typically roughens the surface of the second hardened layer, including the inside of the holes. The roughening treatment may be either a dry or wet roughening treatment. An example of a dry roughening treatment is plasma treatment. An example of a wet roughening treatment is a method in which a swelling treatment using a swelling liquid, a roughening treatment using an oxidizing agent, and a neutralization treatment using a neutralizing liquid are performed in this order.

[0105] For example, the method for manufacturing a component-embedded substrate may involve repeatedly forming a conductor layer and an insulating layer on the second cured layer to produce a component-embedded substrate having a multilayer structure. Examples of component-embedded substrates having a multilayer structure include multilayer printed wiring boards. The insulating layer may be formed, for example, by applying and curing a liquid resin composition, and the same liquid resin composition as in step (III) may be used. The insulating layer may also be formed, for example, by laminating a resin sheet and curing a resin composition layer contained in the resin sheet, and the same resin sheet as in step (V) may be used. Furthermore, the insulating layer may be formed by methods other than these. For example, the insulating layer may be formed using a prepreg formed by impregnating a sheet-like fiber substrate with a resin composition. On the other hand, the conductor layer may be formed, for example, by a method using metal foil, a plating method, a sputtering method, a vapor deposition method, or the like. Furthermore, when forming the conductor layer and the insulating layer, optional processes such as a process of drilling holes in the insulating layer, a desmearing process, or a roughening process may be performed as necessary.

[0106] [Embedded Component Substrate] The embedded component substrate manufactured by the above-described manufacturing method includes a cavity substrate, a component disposed in the cavity of the cavity substrate, a first hardened layer for embedding the component, and a second hardened layer formed on the first hardened layer. The embedded component substrate manufactured in this manner can suppress delamination between the component in the cavity and the first hardened layer. Therefore, even after a HAST test in a high-temperature, high-humidity environment and a reflow process, delamination between the cavity wall and the first hardened layer can be suppressed. Specifically, when a HAST test is performed in which the embedded component substrate is stored in an environment at a temperature of 130°C and a humidity of 85% for 100 hours, delamination between the component and the first hardened layer can be suppressed. Specifically, when a HAST test is performed in which the embedded component substrate is stored in an environment at a temperature of 130°C and a humidity of 85% for 100 hours, and then the reflow process (maximum temperature 260°C) is performed 15 times, delamination between the component and the first hardened layer can be suppressed.

[0107] The component-embedded substrate can suppress delamination that typically occurs between the cavity wall surface and the first hardened layer. Therefore, even after a HAST test in a high-temperature, high-humidity environment and a reflow process, delamination between the cavity wall surface and the first hardened layer can be suppressed. Specifically, when a HAST test is performed in which the component-embedded substrate is stored in an environment at a temperature of 130°C and a humidity of 85% for 100 hours, delamination between the cavity wall surface and the first hardened layer can be suppressed. Specifically, when a HAST test is performed in which the component-embedded substrate is stored in an environment at a temperature of 130°C and a humidity of 85% for 100 hours, and then the reflow process (maximum temperature 260°C) is performed 15 times, delamination between the cavity wall surface and the first hardened layer can be suppressed.

[0108] Furthermore, the component-embedded substrate can suppress delamination that typically occurs between the first hardened layer and the second hardened layer. Therefore, even after a HAST test in a high-temperature, high-humidity environment, delamination between the first hardened layer and the second hardened layer can be suppressed. Specifically, when a HAST test is performed in which the component-embedded substrate is stored in an environment at a temperature of 130°C and a humidity of 85% RH for 100 hours, delamination between the first hardened layer and the second hardened layer can be suppressed.

[0109] Furthermore, the liquid resin composition has excellent embedding properties, which can prevent voids from being formed in the first cured layer, thereby forming a first cured layer with few voids, preferably no voids, in the cavity.

[0110] The component-embedded substrate can be applied to circuit boards such as printed wiring boards, such as multilayer printed wiring boards; and semiconductor chip packages, such as fan-out packages and fan-in packages. The component-embedded substrate may also be mounted on a semiconductor device. Examples of semiconductor devices equipped with a component-embedded substrate include various semiconductor devices used in electrical products (e.g., computers, mobile phones, smartphones, tablet devices, wearable devices, digital cameras, medical equipment, and televisions) and vehicles (e.g., motorcycles, automobiles, trains, ships, and aircraft).

[0111] [Liquid Resin Composition] The liquid resin composition that can be used in the above-described method for manufacturing a component-embedded substrate can be in a liquid state in step (III). Usually, when the liquid resin composition is filled into the cavity in step (III), it is at room temperature or a temperature close to room temperature. Therefore, it is preferable that the liquid resin composition be in a liquid state at room temperature (25°C).

[0112] The liquid resin composition contains a resin. The liquid resin composition includes a resin that can be cured in step (IV). For example, the liquid resin composition may contain a thermosetting resin to enable thermal curing of the liquid resin composition in step (IV). Examples of thermosetting resins include epoxy resins, cyanate ester resins, phenolic resins, bismaleimide-triazine resins, polyimide resins, acrylic resins, and vinylbenzyl resins. One type of thermosetting resin may be used alone, or two or more types may be used in combination. Among these, epoxy resins are preferred as the thermosetting resin.

[0113] Furthermore, the cured product of the liquid resin composition can serve as an insulating layer. Therefore, it is preferable that the cured product of the liquid resin composition have sufficient insulating properties. For this reason, examples of liquid resin compositions include compositions containing an inorganic filler, an epoxy resin, and a curing agent. Therefore, the liquid resin composition contains (A) an inorganic filler, (B) an epoxy resin, and (C) a curing agent. The liquid resin composition may further contain (D) a dispersant, (F) a silane coupling agent, (G) other additives, and (H) a solvent, as needed. In addition to components (A) to (C), the liquid resin composition preferably further contains (D) a dispersant, from the viewpoint of further suppressing seepage of the liquid resin composition toward the periphery of the cavity.

[0114] <(A) Inorganic Filler> The liquid resin composition contains (A) an inorganic filler as component (A). By including (A) the inorganic filler in the liquid resin composition, the average linear thermal expansion coefficient of the cured product can be reduced.

[0115] (A) As the inorganic filler, an inorganic compound is used. Examples of inorganic filler materials include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum silicate, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium titanate zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, silica is particularly suitable. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, hollow silica, etc. Furthermore, spherical silica is preferred.

[0116] The average particle size of component (A) is preferably 10 μm or less, more preferably 8 μm or less, even more preferably 6 μm or less, 5 μm or less, or 4.5 μm or less. The lower limit is preferably 0.5 μm or more, more preferably 0.7 μm or more, even more preferably 1.0 μm or more, 1.2 μm or more, 1.4 μm or more, 1.6 μm or more, 1.8 μm or more, or 2.0 μm or more. When the liquid resin composition contains two or more types of component (A), it is sufficient that the average particle size of all of the components (A) falls within this range. The same applies to the 10% particle size and 90% particle size described below.

[0117] The average particle size of component (A) can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, a particle size distribution of the inorganic filler is prepared on a volume basis using a laser diffraction / scattering particle size distribution measuring device, and the median diameter is used as the average particle size. A measurement sample can be prepared by weighing 100 mg of inorganic filler and 10 g of methyl ethyl ketone into a vial and dispersing the mixture ultrasonically for 10 minutes. The measurement sample is measured using a laser diffraction particle size distribution measuring device, with blue and red light source wavelengths used, using a flow cell system to measure the volume-based particle size distribution of the inorganic filler (A), and the average particle size can be calculated as the median diameter from the obtained particle size distribution. An example of a laser diffraction particle size distribution measuring device is the "LA-960" manufactured by Horiba, Ltd.

[0118] The volume-based particle size distribution of component (A) usually follows a normal distribution. Therefore, component (A) can have a 10% particle size smaller than the average particle size of component (A), and a 90% particle size larger than the average particle size of component (A). Here, the 10% particle size refers to the particle size at which the cumulative volume from the smaller particle size side in the volume-based particle size distribution is 10%. Furthermore, the 90% particle size refers to the particle size at which the cumulative volume from the smaller particle size side in the volume-based particle size distribution is 90%. The 10% particle size and 90% particle size of component (A) can be measured from the volume-based particle size distribution measured by the laser diffraction / scattering method. The average particle size is referred to as D ５０ , 10% particle size is D １０ , and 90% particle size is D ９０ This is what happens.

[0119] The 10% particle size of component (A) is preferably 0.1 μm or more, more preferably 0.3 μm or more, and even more preferably 0.5 μm or more. The upper limit is the average particle size or less, and is preferably 1.5 μm or less, more preferably 1.3 μm or less, and even more preferably 1.2 μm or less.

[0120] The 90% particle size of component (A) is preferably 3 μm or more, more preferably 3.5 μm or more, and even more preferably 4 μm or more. The upper limit is preferably 10 μm or less, more preferably 8 μm or less, and even more preferably 6 μm or less.

[0121] The specific surface area of ​​component (A) is preferably 1 m ２ / g or more, more preferably 1.5m ２ / g or more, more preferably 2m ２ / g or more, particularly preferably 2.5m ２ / g or more. There is no particular upper limit, but it is preferably 60 m ２ / g or less, 50m ２ / g or less or 40m ２ / g or less. The specific surface area is obtained in accordance with the BET method by adsorbing nitrogen gas onto the surface of a sample using a specific surface area measuring device (Macsorb HM-1210 manufactured by Mountech Co., Ltd.) and calculating the specific surface area using the BET multipoint method. When the liquid resin composition contains two or more types of component (A), it is sufficient that the specific surface area of ​​the entire component (A) falls within this range.

[0122] Component (A) may be a commercially available product. Examples of commercially available products of component (A) include "RY-200" and "A200" manufactured by Nippon Aerosil Co., Ltd.; "SP60-05" and "SP507-05" manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YC100C", "YA050C", "YA050C-MJE", "YA010C", "SC2500SQ", "SO-C4", "SO-C2", and "SO-C1" manufactured by Admatechs Co., Ltd.; "UFP-30", "DAW-03", and "FB-105FD" manufactured by Denka Co., Ltd.; "Silfil NSS-3N", "Silfil NSS-4N", and "Silfil NSS-5N" manufactured by Tokuyama Corporation; and "CellSpheres" and "MGH-005" manufactured by Taiheiyo Cement Corporation.

[0123] The component (A) may be treated with a surface treatment agent to enhance moisture resistance and dispersibility. Examples of the surface treatment agent include fluorine-containing silane coupling agents, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, silane coupling agents, alkoxysilanes, organosilazane compounds, and titanate coupling agents. The surface treatment agents may be used alone or in any combination of two or more.

[0124] Commercially available surface treatment agents include, for example, Shin-Etsu Chemical Co., Ltd.'s "KBM403" (3-glycidoxypropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM803" (3-mercaptopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBE903" (3-aminopropyltriethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBE903" (3-aminopropyltriethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "SZ-31" (hexamethyldisilazane), Shin-Etsu Chemical Co., Ltd.'s "KBM103" (phenyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd.'s "KBM-4803" (long-chain epoxy-type silane coupling agent), and Shin-Etsu Chemical Co., Ltd.'s "KBM-7103" (3,3,3-trifluoropropyltrimethoxysilane).

[0125] The degree of surface treatment with the surface treatment agent preferably falls within a specific range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, 100 parts by mass of the inorganic filler is preferably surface-treated with 0.2 to 5 parts by mass of the surface treatment agent, more preferably 0.2 to 3 parts by mass, and even more preferably 0.3 to 2 parts by mass.

[0126] The degree of surface treatment with the surface treatment agent can be evaluated by the amount of carbon per unit surface area of ​​the inorganic filler. From the viewpoint of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of ​​the inorganic filler is set to 0.02 mg / m ２ More than 0.1 mg / m ２ More preferably, 0.2 mg / m or more２ On the other hand, from the viewpoint of suppressing an increase in the melt viscosity of the resin composition, it is more preferable that the content be 1 mg / m ２ Preferably, 0.8 mg / m or less ２ More preferably, 0.5 mg / m or less ２ The following is even more preferred:

[0127] The carbon amount per unit surface area of ​​the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (e.g., methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler that has been surface-treated with a surface treatment agent, and ultrasonic cleaning is performed at 25°C for 5 minutes. After removing the supernatant and drying the solid content, the carbon amount per unit surface area of ​​the inorganic filler can be measured using a carbon analyzer. As the carbon analyzer, an "EMIA-320V" manufactured by Horiba, Ltd. or the like can be used.

[0128] The content (mass %) of component (A) is preferably 50 mass % or more, more preferably 55 mass % or more, and even more preferably 60 mass % or more, and is preferably 95 mass % or less, more preferably 93 mass % or less, and even more preferably 90 mass % or less, when the non-volatile components of the liquid resin composition are taken as 100 mass %.

[0129] The content (vol %) of component (A) is preferably 30 vol % or more, more preferably 35 vol % or more, and even more preferably 40 vol % or more, when the non-volatile components of the liquid resin composition are taken as 100 vol %. The content (vol %) of component (A) is preferably 90 vol % or less, more preferably 85 vol % or less, and even more preferably 80 vol % or less.

[0130] In the present invention, unless otherwise specified, the content of each component in the liquid resin composition is a value when the non-volatile components in the liquid resin composition are taken as 100% by mass, and the non-volatile components refer to all components constituting the liquid resin composition other than the solvent, which will be described later. The volumetric content (vol %) of each component contained in the liquid resin composition can be calculated from the mass of the component contained in the liquid resin composition. Specifically, the volume of each component can be calculated by dividing the mass by the specific gravity, and the volumetric content (vol %) can then be calculated from the volume of each component thus calculated.

[0131] <(B) Epoxy Resin> The liquid resin composition contains (B) epoxy resin as component (B). The (B) epoxy resin can be a curable resin having an epoxy group. By including the (B) epoxy resin in the liquid resin composition, a cured product exhibiting good mechanical strength and insulation reliability can be obtained. One type of (B) epoxy resin may be used alone, or two or more types may be used in combination.

[0132] Examples of the epoxy resin (B) include bixylenol type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, bisphenol AF type epoxy resins, bisphenol E type epoxy resins, dicyclopentadiene type epoxy resins, trisphenol type epoxy resins, phenol novolac type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, cresol novolac type epoxy resins, biphenyl type epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, and alicyclic epoxy resins having an ester skeleton. Examples of the epoxy resin include epoxy resins, heterocyclic epoxy resins, spiro ring-containing epoxy resins, cyclohexane-type epoxy resins, cyclohexanedimethanol-type epoxy resins, trimethylol-type epoxy resins, tetraphenylethane-type epoxy resins, epoxy resins containing a condensed ring skeleton such as naphthylene ether-type epoxy resins, tert-butyl-catechol-type epoxy resins, naphthalene-type epoxy resins, naphthol-type epoxy resins, anthracene-type epoxy resins, and naphthol novolac-type epoxy resins, isocyanurate-type epoxy resins, epoxy resins containing an alkyleneoxy skeleton and a butadiene skeleton, and epoxy resins containing a fluorene structure. One type of (B) epoxy resin may be used alone, or two or more types may be used in combination.

[0133] The epoxy resin (B) preferably contains an epoxy resin having two or more epoxy groups per molecule, and the proportion of the epoxy resin having two or more epoxy groups per molecule relative to 100% by mass of the non-volatile components of the epoxy resin (B) is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

[0134] Epoxy resins include epoxy resins that are liquid at a temperature of 20°C (hereinafter sometimes referred to as "liquid epoxy resins") and epoxy resins that are solid at a temperature of 20°C (hereinafter sometimes referred to as "solid epoxy resins"). The liquid resin composition may contain only a liquid epoxy resin as the (B) epoxy resin, or may contain only a solid epoxy resin, or may contain a combination of a liquid epoxy resin and a solid epoxy resin. From the viewpoint of reducing the viscosity of the liquid resin composition and making it easier to fill a cavity with the liquid resin composition, it is preferable that the liquid resin composition contain only a liquid epoxy resin as the (A) epoxy resin.

[0135] The liquid epoxy resin is preferably a liquid epoxy resin having two or more epoxy groups in one molecule.

[0136] Preferred liquid epoxy resins include bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol AF epoxy resins, bisphenol E epoxy resins, naphthalene epoxy resins, glycidyl ester epoxy resins, glycidyl amine epoxy resins, phenol novolac epoxy resins, alicyclic epoxy resins having an ester skeleton, cyclohexane epoxy resins, cyclohexanedimethanol epoxy resins, epoxy resins having a butadiene structure, epoxy resins containing an alkyleneoxy skeleton and a butadiene skeleton, epoxy resins containing a fluorene structure, and dicyclopentadiene epoxy resins. Among these, any of bisphenol A epoxy resins, bisphenol F epoxy resins, naphthalene epoxy resins, glycidyl amine epoxy resins, cyclohexane epoxy resins, and alicyclic epoxy resins having an ester skeleton is preferred, and any of bisphenol A epoxy resins, bisphenol F epoxy resins, and cyclohexane epoxy resins is more preferred.

[0137] Specific examples of liquid epoxy resins include "YX7400" manufactured by Mitsubishi Chemical Corporation; "HP4032", "HP4032D", and "HP4032SS" (naphthalene-type epoxy resins) manufactured by DIC Corporation; "828US", "828EL", "jER828EL", "825", and "Epikote 828EL" (bisphenol A-type epoxy resins) manufactured by Mitsubishi Chemical Corporation; "jER807" and "1750" (bisphenol F-type epoxy resins) manufactured by Mitsubishi Chemical Corporation; "jER152" (phenol novolac type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "630", "630LSD", and "604" (glycidylamine type epoxy resins) manufactured by Mitsubishi Chemical Corporation; "ED-523T" (glycirol type epoxy resin) manufactured by ADEKA Corporation; "EP-3950L" and "EP-3980S" (glycidylamine type epoxy resins) manufactured by ADEKA Corporation; "EP-4088S" (dicyclopentadiene type epoxy resin) manufactured by ADEKA Corporation; "ZX1059" (a mixture of bisphenol A epoxy resin and bisphenol F epoxy resin) manufactured by Mikal & Materials Corporation; "EX-721" (glycidyl ester epoxy resin) manufactured by Nagase ChemteX Corporation; "EX-991L" (an epoxy resin containing an alkyleneoxy skeleton) manufactured by Nagase ChemteX Corporation; "Celloxide 2021P" and "Celloxide 2081" (alicyclic epoxy resins with an ester skeleton) manufactured by Daicel Corporation; Examples of suitable liquid epoxy resins include "PB-3600," "JP-100," and "JP-200" (epoxy resins having a butadiene structure) manufactured by Nippon Soda Co., Ltd.; "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane-type epoxy resins) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "EG-280" (fluorene structure-containing epoxy resin) manufactured by Osaka Gas Chemicals Co., Ltd.; "EX-201" (cyclic aliphatic glycidyl ether) manufactured by Nagase ChemteX Corporation; and "EPOX MK R710" and "EPOX MK R1710" (bisphenol E-type epoxy resins) manufactured by Printec Co., Ltd. One type of liquid epoxy resin may be used alone, or two or more types may be used in combination.

[0138] As the solid epoxy resin, a solid epoxy resin having three or more epoxy groups in one molecule is preferred, and an aromatic solid epoxy resin having three or more epoxy groups in one molecule is more preferred.

[0139] As the solid epoxy resin, bixylenol type epoxy resin, naphthalene type epoxy resin, naphthalene type tetrafunctional epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, biphenyl type epoxy resin, naphthylene ether type epoxy resin, anthracene type epoxy resin, bisphenol A type epoxy resin, bisphenol AF type epoxy resin, and tetraphenylethane type epoxy resin are preferred, and naphthalene type tetrafunctional epoxy resin and biphenyl type epoxy resin are more preferred.

[0140] Specific examples of solid epoxy resins include "HP4032H" (naphthalene type epoxy resin) manufactured by DIC Corporation; "HP-4700" and "HP-4710" (naphthalene type tetrafunctional epoxy resins) manufactured by DIC Corporation; "N-690" (cresol novolac type epoxy resin) manufactured by DIC Corporation; "N-695" (cresol novolac type epoxy resin) manufactured by DIC Corporation; and "HP-7200", "HP-7200HH", and "HP-7200H" (dicyclopentadiene type epoxy resins) manufactured by DIC Corporation. "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", and "HP6000" (naphthylene ether type epoxy resins) manufactured by DIC Corporation; "EPPN-502H" (trisphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC7000L" (naphthol novolac type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC3000H", "NC3000", "NC3000L", and "NC3100" (biphenyl type epoxy resins) manufactured by Nippon Kayaku Co., Ltd. resin); "ESN475V" (naphthol-type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "ESN485" (naphthol novolac-type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YX4000H", "YX4000", and "YL6121" (biphenyl-type epoxy resins) manufactured by Mitsubishi Chemical Corporation; "YX4000HK" (bixylenol-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "YX8800" (anthracene-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; Examples of the solid epoxy resin include "YX7700" manufactured by Mitsubishi Chemical Corporation (xylene structure-containing novolac type epoxy resin); "PG-100" and "CG-500" manufactured by Osaka Gas Chemicals Co., Ltd.; "YL7760" manufactured by Mitsubishi Chemical Corporation (bisphenol AF type epoxy resin); "YL7800" manufactured by Mitsubishi Chemical Corporation (fluorene type epoxy resin); "jER1010" manufactured by Mitsubishi Chemical Corporation (solid bisphenol A type epoxy resin); and "jER1031S" manufactured by Mitsubishi Chemical Corporation (tetraphenylethane type epoxy resin). One type of solid epoxy resin may be used alone, or two or more types may be used in combination.

[0141] The epoxy equivalent of the (B) epoxy resin is preferably 50 g / eq. to 5000 g / eq., more preferably 50 g / eq. to 3000 g / eq., even more preferably 80 g / eq. to 2000 g / eq., and even more preferably 110 g / eq. to 1000 g / eq. The epoxy equivalent is the mass of a resin containing one equivalent of epoxy groups. This epoxy equivalent can be measured in accordance with JIS K7236.

[0142] The weight average molecular weight (Mw) of the epoxy resin (B) is preferably 100 to 5000, more preferably 200 to 3000, and even more preferably 400 to 1500. The weight average molecular weight of the resin can be measured by gel permeation chromatography (GPC) as a polystyrene-equivalent value.

[0143] The content of the (B) epoxy resin is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more, and is preferably 40% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less, 25% by mass or less, 20% by mass or less, or 15% by mass or less, when the non-volatile components of the liquid resin composition are taken as 100% by mass.

[0144] The content of the (B) epoxy resin, when the resin component of the liquid resin composition is taken as 100% by mass, is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, 75% by mass or more, 80% by mass or more, or 85% by mass or more, and is preferably 99% by mass or less, more preferably 97% by mass or less, and even more preferably 95% by mass or less.

[0145] The "resin component" of the liquid resin composition refers to the non-volatile components contained in the liquid resin composition excluding the inorganic filler.

[0146] <(C) Curing Agent> The liquid resin composition contains a (C) curing agent as the (C) component. This (C) curing agent as the (C) component does not include those corresponding to the above-mentioned components (A) and (B). The (C) curing agent includes an epoxy resin curing agent having the function of curing the (B) epoxy resin, and a curing accelerator having the function of accelerating the curing rate of the (B) epoxy resin. The liquid resin composition preferably contains either an epoxy resin curing agent or a curing accelerator as the (C) curing agent, and more preferably contains a curing accelerator.

[0147] -Epoxy Resin Curing Agent- Examples of epoxy resin curing agents include phenol-based epoxy resin curing agents, naphthol-based epoxy resin curing agents, active ester-based epoxy resin curing agents, amine-based epoxy resin curing agents, acid anhydride-based epoxy resin curing agents, benzoxazine-based epoxy resin curing agents, and cyanate ester-based epoxy resin curing agents. One type of epoxy resin curing agent may be used alone, or two or more types may be used in combination.

[0148] As the phenolic epoxy resin curing agent and naphtholic epoxy resin curing agent, those having a novolac structure are preferred from the viewpoints of heat resistance and water resistance. Furthermore, from the viewpoint of adhesion between the cured product of the liquid resin composition and parts, nitrogen-containing phenolic epoxy resin curing agents are preferred, and triazine skeleton-containing phenolic epoxy resin curing agents are more preferred.

[0149] Specific examples of phenol-based epoxy resin curing agents and naphthol-based epoxy resin curing agents include, for example, "MEH-7700", "MEH-7810", "MEH-7851", and "MEH-8000H" manufactured by Meiwa Chemical Industry Co., Ltd.; "NHN", "CBN", and "GPH" manufactured by Nippon Kayaku Co., Ltd.; "SN-170", "SN-180", "SN-190", "SN-475", "SN-485", "SN-495", and "SN-495V" manufactured by Nippon Steel Chemical & Material Co., Ltd. Examples include "SN-375" and "SN-395"; "TD-2090", "TD-2090-60M", "LA-7052", "LA-7054", "LA-1356", "LA-3018", "LA-3018-50P", "EXB-9500", "HPC-9500", "KA-1160", "KA-1163", and "KA-1165" manufactured by DIC Corporation; and "GDP-6115L", "GDP-6115H", and "ELPC75" manufactured by Gun-ei Chemical Co., Ltd.

[0150] As the active ester-based epoxy resin curing agent, a compound having one or more active ester groups per molecule can be used. Among these, preferred active ester-based epoxy resin curing agents are compounds having two or more highly reactive ester groups per molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds. The active ester-based epoxy resin curing agent is preferably one obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. In particular, from the viewpoint of improving heat resistance, active ester-based epoxy resin curing agents obtained from a carboxylic acid compound and a hydroxy compound are preferred, and active ester-based epoxy resin curing agents obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound are more preferred.

[0151] Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid.

[0152] Examples of phenol compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalene, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadiene-type diphenol compounds, phenol novolak, etc. Here, "dicyclopentadiene-type diphenol compounds" refers to diphenol compounds obtained by condensing one dicyclopentadiene molecule with two phenol molecules.

[0153] Specific preferred examples of the active ester-based epoxy resin curing agent include active ester-based epoxy resin curing agents containing a dicyclopentadiene-type diphenol structure, active ester-based epoxy resin curing agents containing a naphthalene structure, active ester-based epoxy resin curing agents containing an acetylated product of phenol novolac, and active ester-based epoxy resin curing agents containing a benzoylated product of phenol novolac. Among these, active ester-based epoxy resin curing agents containing a naphthalene structure and active ester-based epoxy resin curing agents containing a dicyclopentadiene-type diphenol structure are more preferred. The "dicyclopentadiene-type diphenol structure" refers to a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene.

[0154] Commercially available active ester epoxy resin curing agents include "EXB9451", "EXB9460", "EXB9460S", "HPC-8000L-65TM", "HPC-8000-65T", "EXB-8000H", and "EXB-8000L-65TM" (manufactured by DIC Corporation) as active ester epoxy resin curing agents containing a dicyclopentadiene-type diphenol structure; and "EXB-9416-70BK", "EXB-8100L-65T", "HPC-8150-62T", "EXB-8150L-65T", "EXB-8100L-65T", and "EXB- 8" (manufactured by DIC Corporation); as a phosphorus-containing active ester curing agent, "EXB9401" (manufactured by DIC Corporation), as an active ester curing agent containing an acetylated product of phenol novolac, "DC808" (manufactured by Mitsubishi Chemical Corporation); as active ester curing agents containing a benzoylated product of phenol novolac, "YLH1026," "YLH1030," and "YLH1048" (manufactured by Mitsubishi Chemical Corporation) and "EXB-8500-65T" (manufactured by DIC Corporation); as active ester curing agents containing a styryl group and a naphthalene structure, "PC1300-02-65T" and "PC1300-02-65MA" (manufactured by Air Water Inc.), etc.

[0155] Examples of amine-based epoxy resin curing agents include epoxy resin curing agents having one or more amino groups in one molecule, such as aliphatic amines, polyether amines, alicyclic amines, and aromatic amines. Among these, aromatic amines are preferred. The amine-based epoxy resin curing agent is preferably a primary amine or a secondary amine, and more preferably a primary amine. Specific examples of amine-based epoxy resin curing agents include 4,4'-methylenebis(2,6-dimethylaniline); diaminodiphenyl sulfones such as diphenyldiaminosulfone, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, and 3,3'-diaminodiphenyl sulfone; m-phenylenediamine; m-xylylenediamine; diethyltoluenediamine; 4,4'-diaminodiphenyl ether; 3,3'-dimethyl-4,4'-diaminobiphenyl; 2,2'-dimethyl-4,4'-diaminobiphenyl; 3,3'-dihydroxybenzidine; 2,2-bis(3 1,3-bis(4-aminophenoxy)benzene; 1,3-bis(4-aminophenoxy)benzene; 1,4-bis(4-aminophenoxy)benzene; 4,4'-bis(4-aminophenoxy)biphenyl; bis(4-(4-aminophenoxy)phenyl)sulfone; bis(4-(3-aminophenoxy)phenyl)sulfone, and the like. Commercially available amine-based epoxy resin curing agents may be used, and examples thereof include "KAYABOND C-200S," "KAYABOND C-100," "KAYAHARD A-A," "KAYAHARD A-B," and "KAYAHARD A-S" manufactured by Nippon Kayaku Co., Ltd., and "Epicure W" manufactured by Mitsubishi Chemical Corporation.

[0156] Acid anhydride-based epoxy resin curing agents include epoxy resin curing agents having one or more acid anhydride groups in one molecule. Specific examples of acid anhydride-based epoxy resin curing agents include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarbo Examples of suitable acid anhydrides include carboxylic acid dianhydride, biphenyltetracarboxylic acid dianhydride, naphthalenetetracarboxylic acid dianhydride, oxydiphthalic acid dianhydride, 3,3'-4,4'-diphenylsulfonetetracarboxylic acid dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-C]furan-1,3-dione, ethylene glycol bis(anhydrotrimellitate), and polymeric acid anhydrides such as styrene-maleic acid resins copolymerized with styrene and maleic acid. Commercially available acid anhydride epoxy resin curing agents include, for example, "MH-700" manufactured by New Japan Chemical Co., Ltd.

[0157] Specific examples of benzoxazine-based epoxy resin curing agents include "JBZ-OD100" (benzoxazine ring equivalent 218 g / eq.), "JBZ-OP100D" (benzoxazine ring equivalent 218 g / eq.), and "ODA-BOZ" (benzoxazine ring equivalent 218 g / eq.), all manufactured by JFE Chemical Corporation; "P-d" (benzoxazine ring equivalent 217 g / eq.) and "F-a" (benzoxazine ring equivalent 217 g / eq.), all manufactured by Shikoku Chemicals Corporation; and "HFB2006M" (benzoxazine ring equivalent 432 g / eq.), all manufactured by Showa Highpolymer Co., Ltd.

[0158] Examples of cyanate ester-based epoxy resin curing agents include bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl)thioether, and bis(4-cyanatephenyl)ether; polyfunctional cyanate resins derived from phenol novolac, cresol novolac, etc.; and prepolymers in which these cyanate resins are partially triazine-converted. Specific examples of cyanate ester-based epoxy resin curing agents include "PT30" and "PT60" (phenol novolac-type multifunctional cyanate ester resins), "ULL-950S" (multifunctional cyanate ester resin), "BA230" and "BA230S75" (prepolymers in which part or all of bisphenol A dicyanate has been triazinated to form a trimer), all of which are manufactured by Arxada.

[0159] Specific examples of carbodiimide-based epoxy resin curing agents include Carbodilite (registered trademark) V-03 (carbodiimide group equivalent: 216 g / eq.), V-05 (carbodiimide group equivalent: 262 g / eq.), and V-07 (carbodiimide group equivalent: 200 g / eq.), all manufactured by Nisshinbo Chemical Inc.; and Stavaxol (registered trademark) P (carbodiimide group equivalent: 302 g / eq.), all manufactured by Lanxess AG.

[0160] The active group equivalent of the epoxy resin curing agent is preferably 50 g / eq. to 3000 g / eq., more preferably 100 g / eq. to 1000 g / eq., even more preferably 100 g / eq. to 500 g / eq., and particularly preferably 100 g / eq. to 300 g / eq. The active group equivalent represents the mass of the epoxy resin curing agent per equivalent of the active group.

[0161] The quantitative ratio of (B) epoxy resin to epoxy resin curing agent, expressed as the ratio of [total number of epoxy groups in (B) epoxy resin] to [total number of active groups in epoxy resin curing agent], is preferably in the range of 1:0.01 to 1:10, more preferably 1:0.05 to 1:5, and even more preferably 1:0.1 to 1:3. Here, the active groups in the epoxy resin curing agent are active hydroxyl groups, etc., and vary depending on the type of epoxy resin curing agent. The total number of epoxy groups in the epoxy resin is the sum of the solid content mass of each epoxy resin divided by the epoxy equivalent weight for all epoxy resins. The total number of active groups in the epoxy resin curing agent is the sum of the solid content mass of each epoxy resin curing agent divided by the active group equivalent weight for all epoxy resin curing agents.

[0162] When the resin component of the liquid resin composition is taken as 100% by mass, the content of the epoxy resin curing agent may be 0% by mass or more than 0% by mass, but is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and is preferably 1% by mass or less, more preferably 0.8% by mass or less, even more preferably 0.5% by mass or less.

[0163] The content of the epoxy resin curing agent may be 0% by mass or more than 0% by mass, but is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, and is preferably 1% by mass or less, more preferably 0.8% by mass or less, and even more preferably 0.5% by mass or less, when the non-volatile components of the liquid resin composition are taken as 100% by mass.

[0164] -Curing accelerator- Examples of the curing accelerator include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, and metal-based curing accelerators. Among these, imidazole-based curing accelerators are preferred. One type of curing accelerator may be used alone, or two or more types may be used in combination.

[0165] Examples of the amine curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diazabicyclo(5,4,0)-undecene, 1,8-diazabicyclo[5,4,0]undecene-7,4-dimethylaminopyridine, and 2,4,6-tris(dimethylaminomethyl)phenol, with 4-dimethylaminopyridine being preferred.

[0166] Examples of the phosphorus-based curing accelerator include triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate, with triphenylphosphine and tetrabutylphosphonium decanoate being preferred.

[0167] Examples of the imidazole curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, and 1-benzyl-2-phenylimidazole. 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2, 4-Diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, Examples of imidazole compounds such as phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline, as well as adducts of imidazole compounds and epoxy resins, with 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole being preferred. As the imidazole curing accelerator, commercially available products may be used, such as "P200-H50" manufactured by Mitsubishi Chemical Corporation, and "Curesol 2MZ", "2E4MZ", "Cl1Z", "Cl1Z-CN", "Cl1Z-CNS", "Cl1Z-A", "2MZ-OK", "2MA-OK", "2MA-OK-PW", and "2PHZ" manufactured by Shikoku Chemicals Corporation.

[0168] Examples of guanidine curing accelerators include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene. Examples of suitable biguanide include 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, and 1-(o-tolyl)biguanide. Of these, dicyandiamide and 1,5,7-triazabicyclo[4.4.0]dec-5-ene are preferred.

[0169] Examples of metal-based curing accelerators include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of organometallic complexes include organic cobalt complexes such as cobalt(II) acetylacetonate and cobalt(III) acetylacetonate, organic copper complexes such as copper(II) acetylacetonate, organic zinc complexes such as zinc(II) acetylacetonate, organic iron complexes such as iron(III) acetylacetonate, organic nickel complexes such as nickel(II) acetylacetonate, and organic manganese complexes such as manganese(II) acetylacetonate. Examples of organometallic salts include zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

[0170] The content of the curing accelerator is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less, when the resin component of the liquid resin composition is taken as 100% by mass.

[0171] The content of the curing accelerator is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, and is preferably 8% by mass or less, more preferably 5% by mass or less, and even more preferably 3% by mass or less, when the non-volatile components of the liquid resin composition are taken as 100% by mass.

[0172] The content of the (C) curing agent is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less, when the resin component of the liquid resin composition is taken as 100% by mass.

[0173] The content of the (C) curing agent is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, and is preferably 8% by mass or less, more preferably 5% by mass or less, and even more preferably 3% by mass or less, when the non-volatile components of the liquid resin composition are taken as 100% by mass.

[0174] <(D) Dispersant> The liquid resin composition preferably contains a (D) dispersant in addition to the above-described components (A) to (C). By including a (D) dispersant, it is possible to effectively prevent the liquid resin composition from seeping out to the periphery of the cavity. The (D) dispersant as component (D) does not include those corresponding to the above-described components (A) to (C). One type of (D) dispersant may be used alone, or two or more types may be used in combination.

[0175] As the dispersant (D), a compound capable of suppressing seepage to the outer periphery of the cavity can be used. Such a dispersant preferably has any one of an alkylene skeleton, a (meth)acrylic skeleton, and a polyallylamine skeleton. The (meth)acrylic skeleton is a concept that encompasses both an acrylic skeleton and a methacrylic skeleton.

[0176] The alkylene skeleton is -(CH ２ ) ｎ In the formula, n is preferably 10 or less, more preferably 6 or less, and even more preferably 3 or less, and is preferably 1 or more, and more preferably 2 or more.

[0177] The alkylene skeleton, the (meth)acrylic skeleton, and the polyallylamine skeleton in the (D) dispersant may be present in the main chain or in the side chain, but from the viewpoint of significantly obtaining the effects of the present invention, it is preferable that they be present in the main chain.

[0178] The component (D) may contain an optional skeleton in addition to any of the skeletons of an alkylene skeleton, a (meth)acrylic skeleton, and a polyallylamine skeleton, as long as the effects of the present invention are not impaired. The optional skeleton may, for example, have a structural unit derived from polyester, a structural unit derived from polyoxyalkylene, a structural unit derived from polyether, a structural unit derived from polymaleic acid, a polystyrene structural unit, a structural unit derived from polyvinylamine, etc. Among these optional skeletons, any of the structural units derived from polyester, the structural unit derived from polyoxyalkylene, and the structural unit derived from polyether is preferred, and the structural unit derived from polyoxyalkylene is preferred. When the component (F) has an optional skeleton, the optional skeleton may be a block copolymer with any of the skeletons of an alkylene skeleton, a (meth)acrylic skeleton, and a polyallylamine skeleton, or may be a random copolymer, an alternating copolymer, or a graft copolymer. However, from the viewpoint of significantly achieving the effects of the present invention, it is preferably a block copolymer.

[0179] The structural unit derived from polyester is -(C(=O)-R-O) ｎ - bond. In the formula, n is 2 or more, preferably 5 or more, and more preferably 10 or more. The upper limit is 1,000 or less, preferably 500 or less, more preferably 100 or less, and 50 or less. R each independently represents a divalent hydrocarbon group having 2 to 10 carbon atoms. Examples of the divalent hydrocarbon group include an alkylene group, an alkenylene group, an alkynylene group, and an arylene group.

[0180] Examples of alkylene groups include ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, and decylene groups. Examples of alkenylene groups include ethenylene, propenylene, butenylene, pentenylene, hexenylene, heptenylene, octenylene, nonenylene, and decenylene groups. Examples of alkynylene groups include ethynylene, propenylene, butynylene, pentynylene, hexynylene, heptynylene, octynylene, nonenylene, and decynylene groups. Examples of arylene groups include phenylene and naphthylene groups. Among these, butylene and pentylene groups are preferred for R.

[0181] The structural unit derived from polyoxyalkylene is —O—(CH ２ ) ｎ In the formula, n is preferably 10 or less, more preferably 6 or less, and even more preferably 3 or less, and is preferably 1 or more, and more preferably 2 or more.

[0182] Examples of polyoxyalkylenes include polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene alkylphenyl ethers, polyoxyethylene alkylamines, and polyoxyethylene alkylamides.

[0183] The structural unit derived from polyether refers to a structure having an ether bond -C--O--C--.

[0184] The dispersant (D) preferably has a functional group from the viewpoint of suppressing exudation to the outer periphery of the cavity, that is, the alkylene skeleton, the (meth)acrylic skeleton, and the polyallylamine skeleton preferably have a functional group.

[0185] The functional group may be either a basic group or an acidic group. Examples of the basic group include an amino group; an ammonium group; an imino group; and nitrogen-containing heterocyclic groups such as pyridine, pyrimidine, pyrazine, imidazole, and triazole. Of these, an amino group is preferred. The amino group is a concept that includes a primary amino group, a secondary amino group, and a tertiary amino group. Examples of the acidic group include a carboxy group, a sulfo group (-SO ３ H), sulfate group (-OSO ３ H), phosphono group (-PO(OH) ２ ), a phosphonooxy group (—OPO(OH) ２ ), a hydroxyphosphoryl group (—PO(OH)), a sulfanyl group (—SH), etc., and a carboxy group is preferred. Of these, it is preferred that the functional group has either a carboxy group or an amino group.

[0186] Examples of the terminal group of component (D) include a carboxylic acid residue, an alkoxy group, a hydroxy group, and a hydrogen atom.

[0187] The pH of component (D) can usually be 4 or more and less than 7. The pH can be measured by an indicator method. Specifically, the pH can be measured by immersing a measurement sample (22°C) prepared by dissolving the dispersant in acetone and having a dispersant concentration of 0.1 g / mL into a pH test paper. As the pH test paper, a pH test paper capable of measuring pH in the acidic range (for example, a pH test paper with a measurement range of pH 0.0 to 14.0, pH 1.0 to 14.0, or pH 0.5 to 5.0) can be used, such as the pH test paper "pH Test Paper pH 1-14" (pH measurement range pH 1.0 to 14.0) manufactured by AS ONE Corporation.

[0188] The component (D) may have an acid value within a specific range. From the viewpoint of significantly achieving the effects of the present invention, the acid value of the component (D) is preferably 1 mgKOH / g or more, more preferably 5 mgKOH / g or more, even more preferably 10 mgKOH / g, 20 mgKOH / g, or 30 mgKOH / g, and is preferably 100 mgKOH / g or less, more preferably 90 mgKOH / g or less, even more preferably 80 mgKOH / g or less. The acid value can be measured by neutralization titration.

[0189] Component (D) may have an amine value within a specific range. The amine value of component (D) is preferably 1 mgKOH / g or more, more preferably 5 mgKOH / g or more, and even more preferably 10 mgKOH / g or more, and is preferably 50 mgKOH / g or less, more preferably 45 mgKOH / g or less, and even more preferably 40 mgKOH / g or less. The amine value can be measured by neutralization titration.

[0190] The weight average molecular weight of component (D) is preferably at least 1,000, more preferably at least 1,500, and even more preferably at least 2,000, and is preferably at most 50,000, more preferably at most 40,000, and even more preferably at most 30,000. The weight average molecular weight is the weight molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

[0191] Component (D) can be a commercially available product, such as "SC-1015F" manufactured by NOF Corporation, "PB-821" and "PB-881" manufactured by Ajinomoto Fine-Techno Co., Inc., and "ED400" and "ED-152" manufactured by Kusumoto Chemicals Co., Ltd.

[0192] The content of component (D) is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more, based on 100% by mass of the non-volatile components in the liquid resin composition. The upper limit is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 2% by mass or less, or 1% by mass or less.

[0193] The content of component (D) is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass or more, or 5% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 12% by mass or less, 10% by mass or less, or 8% by mass or less, based on 100% by mass of the resin component of the liquid resin composition.

[0194] <(F) Coupling Agent> In addition to the components described above, the liquid resin composition may contain a (F) coupling agent as an optional component. The (F) coupling agent as this (F) component does not include those corresponding to the above-described components (A) to (D). By including a (F) coupling agent, it is possible to improve the adhesion between the first cured layer and the component. One type of (F) coupling agent may be used alone, or two or more types may be used in combination.

[0195] Examples of the coupling agent (F) include the same coupling agents as those listed as surface treatment agents in the section on the inorganic filler (A).

[0196] The content of the (F) coupling agent is preferably 0.5% by mass or more, more preferably 1% by mass or more, and even more preferably 1.5% by mass or more, and is preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3% by mass or less, when the resin component of the liquid resin composition is taken as 100% by mass.

[0197] The content of the (F) coupling agent is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, and is preferably 3% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less, when the non-volatile components of the liquid resin composition are taken as 100% by mass.

[0198] <(G) Other Additives> In addition to the components described above, the liquid resin composition may further contain any additive as an optional non-volatile component. Examples of such additives include (E) polymer resins (same range as the (e) polymer resin that can be contained in the coating resin composition described later); organic fillers such as rubber particles, polyamide fine particles, and silicone particles; organometallic compounds such as organocopper compounds, organozinc compounds, and organocobalt compounds; colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, and carbon black; polymerization inhibitors such as hydroquinone, catechol, pyrogallol, and phenothiazine; leveling agents such as silicone-based leveling agents and acrylic polymer-based leveling agents; thickeners such as bentone and montmorillonite; and silicone-based defoamers. antifoaming agents such as acrylic antifoaming agents, fluorine-based antifoaming agents, and vinyl resin-based antifoaming agents; ultraviolet absorbers such as benzotriazole-based ultraviolet absorbers; adhesion improvers such as urea silanes; adhesion imparting agents such as triazole-based adhesion imparting agents, tetrazole-based adhesion imparting agents, and triazine-based adhesion imparting agents; antioxidants such as hindered phenol-based antioxidants and hindered amine-based antioxidants; fluorescent brighteners such as stilbene derivatives; surfactants such as fluorine-based surfactants; flame retardants such as phosphorus-based flame retardants (e.g., phosphate ester compounds, phosphazene compounds, phosphinic acid compounds, and red phosphorus), nitrogen-based flame retardants (e.g., melamine sulfate), halogen-based flame retardants, and inorganic flame retardants (e.g., antimony trioxide); etc. The additives may be used alone or in combination of two or more in any ratio.

[0199] From the viewpoint of significantly achieving the effects of the present invention, the liquid resin composition preferably does not contain the polymer resin (E), that is, the content of the polymer resin (E) is preferably 0% by mass.

[0200] <(H) Solvent> The liquid resin composition may further contain a (H) solvent as a volatile component in addition to the non-volatile components (A) to (G) described above. An organic solvent is typically used as the (H) solvent. Examples of organic solvents include ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone; acetate ester solvents such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitol solvents such as cellosolve and butyl carbitol; aromatic hydrocarbon solvents such as toluene and xylene; and amide solvents such as dimethylformamide, dimethylacetamide (DMAc), and N-methylpyrrolidone. One type of (H) solvent may be used alone, or two or more types may be used in combination.

[0201] The amount of the solvent (H) contained in the liquid resin composition may be 0% by mass or more than 0% by mass, but is preferably 0% by mass to 20% by mass, more preferably 0% by mass to 10% by mass, and even more preferably 0% by mass to 5% by mass, relative to 100% by mass of the non-volatile components of the liquid resin composition. Of these, it is particularly preferred that the liquid resin composition does not contain a solvent.

[0202] <Method for producing liquid resin composition> The liquid resin composition can be produced, for example, by mixing the above-mentioned components. The above-mentioned components may be mixed partially or entirely at the same time, or may be mixed sequentially. In the process of mixing each component, the temperature may be appropriately set, and thus heating and / or cooling may be performed temporarily or throughout. Furthermore, stirring or shaking may be performed in the process of mixing each component.

[0203] <Characteristics of Liquid Resin Composition> The viscosity of the liquid resin composition at 25°C is preferably within a specific range from the viewpoint of suppressing exudation to the periphery of the cavity. The specific viscosity range of the liquid resin composition at 25°C is preferably 300 Pa·s or less, more preferably 200 Pa·s or less, even more preferably 170 Pa·s or less, or 150 Pa·s or less. The lower limit is preferably 10 Pa·s or more, more preferably 20 Pa·s or more, and even more preferably 30 Pa·s or more. When the viscosity of the liquid resin composition is equal to or greater than the lower limit, exudation to the periphery of the cavity can be suppressed, and exudation of the liquid resin composition through gaps between the substrate and the temporary bonding material can be suppressed. Furthermore, when the viscosity is equal to or less than the upper limit, particularly good filling properties can be achieved, effectively suppressing the formation of unfilled portions as voids in the cavity. Furthermore, good air evacuation from the cavity can be achieved, effectively suppressing the occurrence of voids.

[0204] When the liquid resin composition is thermally cured in step (IV), the viscosity may decrease as the temperature increases before the curing process begins. Even when the viscosity decreases in this manner, the viscosity of the liquid resin composition is preferably equal to or greater than the lower limit of a specific range of viscosity at 25°C. A liquid resin composition having such a viscosity can prevent the liquid resin composition from seeping through the gap between the substrate and the temporary bonding material, even if the viscosity decreases due to the temperature increase for thermal curing. For example, the viscosity of the liquid resin composition at 50°C may be within the same range as the specific range of viscosity of the liquid resin composition at 25°C.

[0205] The viscosity of the resin composition can be measured using an E-type viscometer RE-80U (manufactured by Toki Sangyo Co., Ltd.) with a cone rotor of 3°×R9.7 calibrated with viscosity calibration standard liquid JS52000 at a rotation speed of 5 rpm.

[0206] The viscosity of the liquid resin composition can be adjusted by the composition of the liquid resin composition, for example, by using an appropriate amount of low-viscosity epoxy resin (B), an appropriate amount of inorganic filler (A), or an appropriate amount of solvent (H).

[0207] <Characteristics of the cured product of the liquid resin composition> In the above-described method for manufacturing a component-embedded substrate, the first cured layer is formed from the cured product of the liquid resin composition. Therefore, the first cured layer usually contains the cured product of the liquid resin composition, and preferably contains only the cured product of the liquid resin composition. Therefore, the first cured layer usually has the same properties as the cured product of the liquid resin composition. From the viewpoint of appropriately controlling the properties of the first cured layer to obtain a high-quality component-embedded substrate, it is preferable that the cured product of the liquid resin composition have appropriate properties. Specifically, it is preferable that the cured product of the liquid resin composition have the following properties.

[0208] Average linear thermal expansion coefficient α of the cured product of the liquid resin composition at 25°C Ｌ is less than 20 ppm / °C, preferably 19.5 ppm / °C or less, more preferably 19 ppm / °C or less, and even more preferably 18 ppm / °C or less. The lower limit is preferably 1 ppm / °C or more, more preferably 3 ppm / °C or more, and even more preferably 5 ppm / °C or more. The average linear thermal expansion coefficient α of the cured product of the liquid resin composition Ｌ can be measured by the method described in the Examples below.

[0209] The first cured layer containing the cured product of the liquid resin composition is selectively formed in a limited area, i.e., within the cavity. Therefore, even if the cured product of the liquid resin composition has a large average linear thermal expansion coefficient, the influence of the first cured layer on the entire component-embedded substrate can be reduced. Furthermore, liquid resin compositions that yield cured products with a large average linear thermal expansion coefficient tend to have high fluidity and excellent component embeddability, so the average linear thermal expansion coefficient at 25°C of cured products of conventionally used liquid resin compositions has tended to be large.

[0210] However, when the thickness of the substrate in which the cavity is formed is 1.0 mm or more, the average linear thermal expansion coefficient of the substrate tends to be low. If the average linear thermal expansion coefficient of the liquid resin composition filled into the cavity is large as in the past, a mismatch in the average linear thermal expansion coefficient occurs between the substrate and the cured product of the liquid resin composition, resulting in delamination between the component in the cavity and the insulating layer. In the present invention, the average linear thermal expansion coefficient of the cured product of the liquid resin composition is low, so the mismatch in the average linear thermal expansion coefficient between the substrate and the cured product of the liquid resin composition is eliminated, and as a result, delamination between the component in the cavity and the insulating layer can be suppressed.

[0211] Average linear thermal expansion coefficient α of the cured product of the liquid resin composition Ｌ can be adjusted by the composition of the liquid resin composition. For example, by using an appropriate amount of (A) inorganic filler, the average linear thermal expansion coefficient α of the cured product of the liquid resin composition can be adjusted by Ｌ can be adjusted within the above range.

[0212] Elastic modulus E of the cured liquid resin composition at 25°C Ｌ is preferably 3.5 GPa or more, more preferably 4 GPa or more, and even more preferably 4.5 GPa or more. The upper limit is preferably 30 GPa or less, more preferably 25 GPa or less, and even more preferably 20 GPa or less. The elastic modulus E of the cured product of the liquid resin composition at 25°C Ｌ When the modulus of elasticity E of the cured product of the liquid resin composition is in the above range, it is possible to suppress the occurrence of delamination between the part in the cavity and the first cured product layer. Ｌ can be measured by the method described in the Examples below.

[0213] Elastic modulus E of the cured liquid resin composition Ｌ can be adjusted by the composition of the liquid resin composition. For example, by using an appropriate amount of the epoxy resin (B) or an appropriate amount of the component (A), the elastic modulus E of the cured product of the liquid resin composition can be adjusted. Ｌ can be adjusted within the above range.

[0214] The liquid resin composition has a low viscosity at 25°C and therefore exhibits excellent embeddability. For example, an evaluation substrate having 20 cavities is observed, and the number of voids generated in the cavities is counted. At this time, there are no voids in any of the 20 cavities. The embeddability can be evaluated by the method described in the examples below.

[0215] The liquid resin composition has a low viscosity at 25°C, and therefore exhibits the property of being able to suppress exudation to the periphery of the cavity. For example, an evaluation substrate having 20 cavities is observed, and the maximum amount of exudation of the cured liquid resin composition to the periphery of the cavity is measured using a digital microscope, and the maximum amount of exudation is averaged. In this case, the average value of the maximum amount of exudation is preferably less than 1000 μm, more preferably less than 200 μm. The exudation to the periphery of the cavity can be evaluated by the method described in the Examples below.

[0216] [Coating Resin Composition Layer] The coating resin composition layer that can be used in the above-described method for producing a component-embedded substrate is a layer containing a coating resin composition, and typically contains only the coating resin composition. This coating resin composition contains a resin. The coating resin composition includes a resin that can be cured in step (VI). For example, the coating resin composition may contain a thermosetting resin to enable thermal curing of the coating resin composition layer in step (VI). The thermosetting resin may contain, for example, the same resin as the thermosetting resin that the liquid resin composition may contain. One type of thermosetting resin may be used alone, or two or more types may be used in combination. Among these, epoxy resins are preferred as thermosetting resins.

[0217] Furthermore, the cured product of the coating resin composition can serve as an insulating layer. Therefore, it is preferable that the cured product of the coating resin composition has sufficient insulating properties. For this reason, the coating resin composition may include a composition containing an inorganic filler. Therefore, the coating resin composition contains (a) an inorganic filler. The liquid resin composition may further contain (b) an epoxy resin, (c) a curing agent, (e) a polymer resin, (g) other additives, and (h) a solvent, as necessary.

[0218] <(a) Inorganic Filler> The coating resin composition contains (a) an inorganic filler as component (a). The (a) inorganic filler can be one within the same range as the (A) inorganic filler of the liquid resin composition. One type of (a) inorganic filler may be used alone, or two or more types may be used in combination.

[0219] The average particle size of component (a) is preferably 2 μm or less, more preferably 1.5 μm or less, even more preferably 0.8 μm or less, 1 μm or less, or 0.5 μm or less. The lower limit is preferably 0.01 μm or more, more preferably 0.05 μm or more, even more preferably 0.07 μm or more, 0.08 μm or more, 0.09 μm or more, or 0.1 μm or more. The average particle size of component (a) can be measured by the same method as for the average particle size of component (A). When the coating resin composition contains two or more types of component (a), it is sufficient that the average particle size of all of the components (a) is within this range.

[0220] The specific surface area of ​​component (a) is preferably 1 m ２ / g or more, more preferably 1.5m ２ / g or more, more preferably 2m ２ / g or more, particularly preferably 2.5m ２ / g or more. There is no particular upper limit, but it is preferably 60 m ２ / g or less, 50m ２ / g or less or 40m ２ / g or less. The specific surface area can be measured by the same method as that for measuring the specific surface area of ​​component (A). When the coating resin composition contains two or more types of component (a), it is sufficient that the specific surface area of ​​all of the components (a) is within this range.

[0221] The content (mass %) of component (a) is preferably 20 mass % or more, more preferably 30 mass % or more, and even more preferably 35 mass % or more, when the non-volatile components of the coating resin composition are taken as 100 mass %. It is preferably 95 mass % or less, more preferably 90 mass % or less, and even more preferably 85 mass % or less.

[0222] The content (vol %) of component (a) is preferably 10 vol % or more, more preferably 18 vol % or more, and even more preferably 20 vol % or more, when the non-volatile components of the coating resin composition are taken as 100 vol %. The content is preferably 80 vol % or less, more preferably 75 vol % or less, and even more preferably 70 vol % or less.

[0223] The non-volatile components refer to all components constituting the coating resin composition other than the solvent, which will be described later. The volumetric content (vol %) of each component contained in the coating resin composition can be calculated from the mass of the component contained in the coating resin composition. Specifically, the mass is divided by the specific gravity to determine the volume of each component, and the volumetric content (vol %) can be calculated from the volume of each component thus determined.

[0224] When the content of component (a) when the non-volatile components of the coating resin composition are taken as 100% by mass is defined as a, and the content of component (A) when the non-volatile components of the liquid resin composition are taken as 100% by mass is defined as A, A / a is preferably 0.5 or more, more preferably 0.7 or more, even more preferably 0.8 or more, or 1 or more, and is preferably 3 or less, more preferably 2.5 or less, even more preferably 2 or less, or 1.8 or less.

[0225] When the average particle size of the component (a) contained in the coating resin composition is ap and the average particle size of the component (A) contained in the liquid resin composition is Ap, Ap / ap is preferably 1 or more, more preferably 2 or more, and even more preferably 5 or more, and is preferably 35 or less, more preferably 25 or less, and even more preferably 20 or less.

[0226] <(b) Epoxy Resin> The coating resin composition contains a (b) epoxy resin as the component (b). The (b) epoxy resin can be one within the same range as the (B) epoxy resin of the liquid resin composition. The (b) epoxy resin may be used alone or in combination of two or more.

[0227] The (b) epoxy resin preferably contains an epoxy resin having two or more epoxy groups per molecule. The proportion of the epoxy resin having two or more epoxy groups per molecule relative to 100% by mass of the non-volatile components of the (b) epoxy resin is preferably the same as the proportion of the epoxy resin having two or more epoxy groups per molecule in the (B) epoxy resin of the liquid resin composition.

[0228] The coating resin composition may contain, as the (b) epoxy resin, only a liquid epoxy resin, or only a solid epoxy resin, or may contain a combination of a liquid epoxy resin and a solid epoxy resin. Among these, the (b) epoxy resin preferably contains a combination of a liquid epoxy resin and a solid epoxy resin.

[0229] The epoxy equivalent weight of the (b) epoxy resin may be in the same range as the epoxy equivalent weight of the (B) epoxy resin of the liquid resin composition.

[0230] The weight average molecular weight (Mw) of the (b) epoxy resin may be in the same range as the weight average molecular weight (Mw) of the (B) epoxy resin of the liquid resin composition.

[0231] The content of the (b) epoxy resin is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass or more, and is preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less, when the resin component of the coating resin composition is taken as 100% by mass.

[0232] The content of (b) the epoxy resin is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, and is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less, when the non-volatile components of the coating resin composition are taken as 100% by mass.

[0233] <(c) Curing Agent> The coating resin composition may contain a (c) curing agent as an optional component in addition to the components (a) and (b). The (c) curing agent may be one within the same range as the (C) curing agent of the liquid resin composition. The (c) curing agent may be used alone or in combination of two or more types.

[0234] The coating resin composition preferably contains, as the curing agent (c), either an epoxy resin curing agent or a curing accelerator, and more preferably contains both an epoxy resin curing agent and a curing accelerator.

[0235] The active group equivalent weight of the epoxy resin curing agent may be in the same range as the active group equivalent weight of the epoxy resin curing agent in the (C) curing agent of the liquid resin composition.

[0236] The quantitative ratio of the (b) epoxy resin to the epoxy resin curing agent, expressed as the ratio of [total number of epoxy groups in the (b) epoxy resin]:[total number of active groups in the epoxy resin curing agent], is preferably in the range of 1:0.01 to 1:10, more preferably 1:0.05 to 1:5, and even more preferably 1:0.1 to 1:3.

[0237] The content of the epoxy resin curing agent is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, and is preferably 45% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less, when the resin component of the coating resin composition is taken as 100% by mass.

[0238] The content of the epoxy resin curing agent is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, and is preferably 35% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less, when the non-volatile components of the coating resin composition are taken as 100% by mass.

[0239] The content of the curing accelerator is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, and is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 1% by mass or less, when the resin component of the coating resin composition is taken as 100% by mass.

[0240] The content of the curing accelerator is preferably 0.005% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.02% by mass or more, and is preferably 1.5% by mass or less, more preferably 1% by mass or less, and even more preferably 0.5% by mass or less, when the non-volatile components of the coating resin composition are taken as 100% by mass.

[0241] The content of (c) the curing agent is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, and is preferably 45% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less, when the resin component of the coating resin composition is taken as 100% by mass.

[0242] The content of (c) the curing agent is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, when the non-volatile components of the coating resin composition are taken as 100% by mass, and is preferably 35% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less.

[0243] <(e) Polymer Resin> The liquid resin composition may contain a (e) polymer resin as an optional component in addition to the above-described components (a) to (c). The (e) polymer resin as component (e) does not include those corresponding to the above-described components (a) to (c). One type of (e) polymer resin may be used alone, or two or more types may be used in combination.

[0244] The (e) polymer resin usually has a weight-average molecular weight greater than that of the (b) epoxy resin, and can exert the effect of reducing the elastic modulus of the cured product of the coating resin composition. The specific weight-average molecular weight of the (e) polymer resin is usually greater than 5,000, preferably 8,000 or more, more preferably 10,000 or more, even more preferably 20,000 or more, particularly preferably 30,000 or more, and preferably 100,000 or less, more preferably 70,000 or less, particularly preferably 60,000 or less.

[0245] Examples of the (e) polymer resin include (e-1) elastomers. The (e-1) elastomers can effectively reduce the elastic modulus of the cured product of the coating resin composition. The (e-1) elastomers may be used alone or in combination of two or more.

[0246] As the (e-1) elastomer, a compound having, in its molecule, one or more structures selected from a polybutadiene structure, a polysiloxane structure, a poly(meth)acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyisobutylene structure, a polyester structure, and a polycarbonate structure is preferred. Furthermore, a compound having, in its molecule, one or more structures selected from the group consisting of a polybutadiene structure, a poly(meth)acrylate structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyester structure, and a polycarbonate structure is even more preferred. Furthermore, a compound having, in its molecule, one or more structures selected from the group consisting of a polybutadiene structure, a polyester structure, and a polycarbonate structure is particularly preferred. The term "(meth)acrylate" encompasses methacrylates, acrylates, and combinations thereof. These structures may be contained in the main chain or side chain of the elastomer molecule.

[0247] An example of the (e-1) elastomer is a resin containing a polybutadiene structure. The polybutadiene structure may be contained in the main chain or in a side chain. The polybutadiene structure may be partially or entirely hydrogenated. A resin containing a polybutadiene structure is sometimes called a polybutadiene resin. Examples of polybutadiene resins include "Ricon 130MA8," "Ricon 130MA13," "Ricon 130MA20," "Ricon 131MA5," "Ricon 131MA10," "Ricon 131MA17," "Ricon 131MA20," and "Ricon 184MA6" (acid anhydride group-containing polybutadienes) manufactured by Cray Valley Corporation; "GQ-1000" (hydroxyl- and carboxyl-group-introduced polybutadiene), "G-1000," "G-2000," and "G-3000" (polybutadiene with hydroxyl groups at both ends), "GI-1000," "GI-2000," and "GI-3000" (hydrogenated polybutadiene with hydroxyl groups at both ends) manufactured by Nippon Soda Co., Ltd.; and "FCA-061L" (hydrogenated polybutadiene skeleton epoxy resin) manufactured by Nagase ChemteX Corporation. Examples of polybutadiene resins include hydroxyl-terminated polybutadiene, linear polyimides made from diisocyanate compounds and tetrabasic acid anhydrides (polyimides described in JP 2006-37083 A and WO 2008 / 153208 A), and phenolic hydroxyl group-containing butadienes. The content of the butadiene structure in the polyimide resin is preferably 60% by mass to 95% by mass, more preferably 75% by mass to 85% by mass. For details of the polyimide resin, please refer to the descriptions in JP 2006-37083 A and WO 2008 / 153208 A, the contents of which are incorporated herein by reference.

[0248] Another example of the (e-1) elastomer is a resin containing a poly(meth)acrylate structure. A resin containing a poly(meth)acrylate structure is sometimes called a poly(meth)acrylic resin. Examples of poly(meth)acrylic resins include Teisan Resin manufactured by Nagase ChemteX Corporation, and ME-2000, W-116.3, W-197C, KG-25, and KG-3000 manufactured by Negami Chemical Industrial Co., Ltd.

[0249] Another example of the (e-1) elastomer is a resin containing a polycarbonate structure. Resins containing a polycarbonate structure are sometimes referred to as polycarbonate resins. Examples of polycarbonate resins include "T6002" and "T6001" (polycarbonate diols) manufactured by Asahi Kasei Corporation, and "C-1090," "C-2090," and "C-3090" (polycarbonate diols) manufactured by Kuraray Co., Ltd. Linear polyimides made from hydroxyl-terminated polycarbonates, diisocyanate compounds, and tetrabasic acid anhydrides can also be used. The carbonate structure content of the polyimide resin is preferably 60% to 95% by mass, more preferably 75% to 85% by mass. For details of the polyimide resin, please refer to the description in International Publication No. WO 2016 / 129541, the contents of which are incorporated herein by reference.

[0250] Another example of the (e-1) elastomer is a resin containing a polysiloxane structure. A resin containing a polysiloxane structure is sometimes called a siloxane resin. Examples of siloxane resins include "SMP-2006," "SMP-2003PGMEA," and "SMP-5005PGMEA" manufactured by Shin-Etsu Silicones Co., Ltd., and linear polyimides made from amine-terminated polysiloxanes and tetrabasic acid anhydrides (see, for example, WO 2010 / 053185, JP 2002-12667 A, and JP 2000-319386 A).

[0251] Further examples of the (e-1) elastomer include resins containing a polyalkylene structure or a polyalkyleneoxy structure. Resins containing a polyalkylene structure are sometimes called polyalkylene resins, and resins containing a polyalkyleneoxy structure are sometimes called polyalkyleneoxy resins. The polyalkyleneoxy structure is preferably a polyalkyleneoxy structure having 2 to 15 carbon atoms, more preferably a polyalkyleneoxy structure having 3 to 10 carbon atoms, and even more preferably a polyalkyleneoxy structure having 5 to 6 carbon atoms. Specific examples of polyalkylene resins and polyalkyleneoxy resins include "PTXG-1000" and "PTXG-1800" manufactured by Asahi Kasei Fibers Corporation.

[0252] Another example of the (e-1) elastomer is a resin containing a polyisoprene structure. A resin containing a polyisoprene structure is sometimes called a polyisoprene resin. Examples of polyisoprene resins include "KL-610" and "KL613" manufactured by Kuraray Co., Ltd.

[0253] Another example of the (e-1) elastomer is a resin containing a polyisobutylene structure. A resin containing a polyisobutylene structure is sometimes called a polyisobutylene resin. Examples of polyisobutylene resins include "SIBSTAR-073T" (styrene-isobutylene-styrene triblock copolymer) and "SIBSTAR-042D" (styrene-isobutylene diblock copolymer), both manufactured by Kaneka Corporation.

[0254] Another example of the (e-1) elastomer is a resin containing a polyester structure. A resin containing a polyester structure is sometimes called a polyester resin. Examples of polyester resins include "Vylon 600," "Vylon 560," "Vylon 230," "Vylon GK-360," and "Vylon BX-1001" manufactured by Toyobo Co., Ltd., and "LP-035," "LP-011," "TP-220," "TP-249," and "SP-185" manufactured by Mitsubishi Chemical Corporation.

[0255] The (e-1) elastomer may have a functional group capable of reacting with the (b) epoxy resin. The functional group capable of reacting with the (b) epoxy resin also includes a functional group that appears upon heating. In one embodiment, the functional group capable of reacting with the (b) epoxy resin may be one or more functional groups selected from the group consisting of a hydroxy group, a carboxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group, and a urethane group. Among these, the functional group is preferably a hydroxy group, an acid anhydride group, a phenolic hydroxyl group, an epoxy group, an isocyanate group, or a urethane group, more preferably a hydroxy group, an acid anhydride group, a phenolic hydroxyl group, or an epoxy group, and particularly preferably a phenolic hydroxyl group. However, when the (e-1) elastomer contains an epoxy group as a functional group, the weight average molecular weight (Mw) of the (e-1) elastomer is preferably 5,000 or more.

[0256] The (e-1) elastomer preferably has a large number average molecular weight. The specific number average molecular weight (Mn) of the (e-1) elastomer is preferably 1,000 or more, more preferably 1,500 or more, even more preferably 3,000 or more, and particularly preferably 5,000 or more. The upper limit is preferably 1,000,000 or less, more preferably 900,000 or less. The number average molecular weight (Mn) is the number average molecular weight in terms of polystyrene measured using GPC (gel permeation chromatography).

[0257] The (e-1) elastomer preferably has a low glass transition temperature (Tg). The specific glass transition temperature (Tg) of the (e-1) elastomer is preferably 30°C or lower, more preferably 20°C or lower, and even more preferably 10°C or lower, and is preferably -60°C or higher, more preferably -50°C or higher, and even more preferably -45°C or higher.

[0258] Examples of the (e) polymer resin include (e-2) polyether skeleton-containing compounds. The (e-2) polyether skeleton-containing compounds can effectively reduce the elastic modulus of the cured product of the coating resin composition. The (e-2) polyether skeleton-containing compounds may be used alone or in combination of two or more.

[0259] The (e-2) polyether skeleton-containing compound refers to a polymer compound having a polyether skeleton. This (e-2) polyether skeleton-containing compound does not include the above-mentioned components (a) to (c) or the (e-1) elastomer. The polyether skeleton contained in the (e-2) polyether skeleton-containing compound is preferably a polyoxyalkylene skeleton composed of one or more monomer units selected from ethylene oxide units and propylene oxide units. Therefore, the (e-2) polyether skeleton-containing compound preferably does not contain a polyether skeleton containing a monomer unit having 4 or more carbon atoms, such as a butylene oxide unit or a phenylene oxide unit. Furthermore, the (e-2) polyether skeleton-containing compound may contain a hydroxy group.

[0260] The polyether skeleton-containing compound (e-2) may contain a silicone skeleton. Examples of the silicone skeleton include polydialkylsiloxane skeletons such as polydimethylsiloxane skeletons; polydiarylsiloxane skeletons such as polydiphenylsiloxane skeletons; polyalkylarylsiloxane skeletons such as polymethylphenylsiloxane skeletons; polydialkyl-diarylsiloxane skeletons such as polydimethyl-diphenylsiloxane skeletons; polydialkyl-alkylarylsiloxane skeletons such as polydimethyl-methylphenylsiloxane skeletons; and polydiaryl-alkylarylsiloxane skeletons such as polydiphenyl-methylphenylsiloxane skeletons. A polydialkylsiloxane skeleton is preferred, and a polydimethylsiloxane skeleton is particularly preferred. The polyether skeleton-containing compound (e-2) containing a silicone skeleton may be, for example, a polyoxyalkylene-modified silicone, an alkyl-etherified polyoxyalkylene-modified silicone (a polyoxyalkylene-modified silicone in which at least a portion of the polyether skeleton terminals are alkoxy groups), or the like.

[0261] The polyether skeleton-containing compound (e-2) may contain a polyester skeleton. This polyester skeleton is preferably an aliphatic polyester skeleton. The hydrocarbon chain contained in the aliphatic polyester skeleton may be linear or branched, but branched is preferred. The number of carbon atoms contained in the polyester skeleton may be, for example, 4 to 16. Since the polyester skeleton can be formed from a polycarboxylic acid, a lactone, or an anhydride thereof, the polyether skeleton-containing compound (e-2) containing a polyester skeleton may have a carboxyl group at the molecular terminal, but preferably has a hydroxy group at the molecular terminal.

[0262] Examples of the (e-2) polyether skeleton-containing compound include linear polyoxyalkylene glycols (linear polyalkylene glycols) such as polyethylene glycol, polypropylene glycol, and polyoxyethylene polyoxypropylene glycol; polyoxyethylene glyceryl ether, polyoxypropylene glyceryl ether, polyoxyethylene polyoxypropylene glyceryl ether, polyoxyethylene trimethylolpropane ether, polyoxypropylene trimethylolpropane ether, polyoxyethylene polyoxypropylene trimethylolpropane ether, polyoxyethylene diglyceryl ether, polyoxypropylene diglyceryl ether, polyoxyethylene polyoxypropylene diglyceryl ether, polyoxyethylene pentaerythritol ether, polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene sorbitol ... polyoxyalkylene glycols (polyalkylene glycols) such as multi-chain polyoxyalkylene glycols (multi-chain polyalkylene glycols) such as dipropylene sorbite and polyoxyethylene polyoxypropylene sorbite; polyoxyalkylene alkyl ethers such as polyoxyethylene monoalkyl ethers, polyoxyethylene dialkyl ethers, polyoxypropylene monoalkyl ethers, polyoxypropylene dialkyl ethers, polyoxyethylene polyoxypropylene monoalkyl ethers, and polyoxyethylene polyoxypropylene dialkyl ethers; polyoxyalkylene esters (including acetate esters, propionate esters, butyrate esters, (meth)acrylate esters, etc.) such as polyoxyethylene monoesters, polyoxyethylene diesters, polypropylene glycol monoesters, polypropylene glycol diesters, polyoxyethylene polyoxypropylene monoesters, and polyoxyethylene polyoxypropylene diesters;Polyoxyalkylene alkyl ether esters (including acetate esters, propionate esters, butyrate esters, (meth)acrylate esters, etc.) such as polyoxyethylene monoesters, polyoxyethylene diesters, polyoxypropylene monoesters, polyoxypropylene diesters, polyoxyethylene polyoxypropylene monoesters, polyoxyethylene polyoxypropylene diesters, polyoxyethylene alkyl ether esters, polyoxypropylene alkyl ether esters, and polyoxyethylene polyoxypropylene alkyl ether esters; polyoxyalkylene alkylamines such as polyoxyethylene alkylamines, polyoxypropylene alkylamines, and polyoxyethylene polyoxypropylene alkylamines; polyoxyalkylene alkylamides such as polyoxyethylene alkylamides, polyoxypropylene alkylamides, and polyoxyethylene polyoxypropylene alkylamides; polyoxyethylene dimethicone, poly Examples thereof include polyoxyalkylene-modified silicones such as polyoxypropylene dimethicone, polyoxyethylene polyoxypropylene dimethicone, polyoxyethylene polydimethylsiloxyalkyl dimethicone, polyoxypropylene polydimethylsiloxyalkyl dimethicone, and polyoxyethylene polyoxypropylene polydimethylsiloxyalkyl dimethicone; and alkyl-etherified polyoxyalkylene-modified silicones (polyoxyalkylene-modified silicones in which at least a portion of the polyether skeleton terminals are alkoxy groups) such as polyoxyethylene alkyl ether dimethicone, polyoxypropylene alkyl ether dimethicone, polyoxyethylene polyoxypropylene alkyl ether dimethicone, polyoxyethylene alkyl ether polydimethylsiloxyalkyl dimethicone, polyoxypropylene alkyl ether polydimethylsiloxyalkyl dimethicone, and polyoxyethylene polyoxypropylene alkyl ether polydimethylsiloxyalkyl dimethicone;

[0263] (e-2) Commercially available polyether skeleton-containing compounds include, for example, "Pronon #102," "Pronon #104," "Pronon #201," "Pronon #202B," "Pronon #204," "Pronon #208," "Unilube 70DP-600B," and "Unilube 70DP-950B" (polyoxyethylene polyoxypropylene glycols) manufactured by NOF Corporation; "Pluronic L-23," "Pluronic L-31," and "Pluronic L-41" manufactured by ADEKA Corporation. Pluronic L-44, Pluronic L-61, Adeka Pluronic L-62, Pluronic L-64, Pluronic L-71, Pluronic L-72, Pluronic L-101, Pluronic L-121, Pluronic P-84, Pluronic P-85, Pluronic P-103, Pluronic F-68, Pluronic F-88, Pluronic F-108, Pluronic 25R-1 "Pluronic 25R-2", "Pluronic 17R-2", "Pluronic 17R-3", "Pluronic 17R-4" (polyoxyethylene polyoxypropylene glycol); "KF-6011", "KF-6011P", "KF-6012", "KF-6013", "KF-6015", "KF-6016", "KF-6017", "KF-6017P", "KF-6043", "KF-6004", "KF35" manufactured by Shin-Etsu Silicone Co., Ltd. 1A", "KF352A", "KF353", "KF354L", "KF355A", "KF615A", "KF945", "KF-640", "KF-642", "KF-643", "KF-644", "KF-6020", "KF-6204", "X22-4515", "KF-6028", "KF-6028P", "KF-6038", "KF-6048", and "KF-6025" (polyoxyalkylene-modified silicone).

[0264] The number average molecular weight of the polyether skeleton-containing compound (e-2) is preferably 500 to 40,000, more preferably 500 to 20,000, and even more preferably 500 to 10,000.

[0265] The polyether skeleton-containing compound (e-2) is preferably liquid at 25°C. The viscosity of the polyether skeleton-containing compound (e-2) at 25°C is preferably 100,000 mPa·s or less, more preferably 50,000 mPa·s or less, even more preferably 30,000 mPa·s or less, even more preferably 10,000 mPa·s or less, even more preferably 5,000 mPa·s or less, even more preferably 4,000 mPa·s or less, even more preferably 3,000 mPa·s or less, even more preferably 2,000 mPa·s or less, and particularly preferably 1,500 mPa·s or less. The lower limit of the viscosity of the polyether skeleton-containing compound (e-2) at 25°C is preferably 10 mPa·s or more, more preferably 20 mPa·s or more, even more preferably 30 mPa·s or more, even more preferably 40 mPa·s or more, and particularly preferably 50 mPa·s or more. The viscosity may be a viscosity (mPa·s) obtained by measurement using a Brookfield viscometer.

[0266] Examples of the (e) polymer resin include (e-3) thermoplastic resin. The (e-3) thermoplastic resin does not include the above-mentioned components (a) to (c), (e-1) elastomer, and (e-2) polyether skeleton-containing compound. The (E-3) thermoplastic resin may be used alone or in combination of two or more.

[0267] Examples of the thermoplastic resin (e-3) include phenoxy resin, polyvinyl acetal resin, polyolefin resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, polyetheretherketone resin, and polyester resin. The thermoplastic resin (e-3) may be used alone or in combination of two or more. Among the thermoplastic resins (e-3), phenoxy resin is preferred.

[0268] Examples of the phenoxy resin include phenoxy resins having one or more skeletons selected from the group consisting of bisphenol A, bisphenol F, bisphenol S, bisphenolacetophenone, novolac, biphenyl, fluorene, dicyclopentadiene, norbornene, naphthalene, anthracene, adamantane, terpene, and trimethylcyclohexane. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. Specific examples of phenoxy resins include "1256" and "4250" (both phenoxy resins containing a bisphenol A skeleton), "YX8100" (phenoxy resin containing a bisphenol S skeleton), and "YX6954" (phenoxy resin containing a bisphenol acetophenone skeleton) manufactured by Mitsubishi Chemical Corporation; "FX280" and "FX293" manufactured by Nippon Steel Chemical & Material Co., Ltd.; and "YL7500BH30," "YX6954BH30," "YX7553," "YX7553BH30," "YL7769BH30," "YL6794," "YL7213," "YL7290," and "YX7482" manufactured by Mitsubishi Chemical Corporation.

[0269] The content of (e) the polymer resin is preferably 1% by mass or more, more preferably 1.5% by mass or more, and even more preferably 2% by mass or more, and is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, when the resin component of the coating resin composition is taken as 100% by mass.

[0270] The content of (e) the polymer resin is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, when the non-volatile components of the coating resin composition are taken as 100% by mass, and is preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less.

[0271] <(g) Other Additives> In addition to the above-described components (a) to (c) and component (e), the coating resin composition may further contain an optional additive (g) as an optional non-volatile component. Such additives may include the other additives (G) that may be contained in the liquid resin composition, as well as those in the same range as the dispersant (D) and the coupling agent (F). These other additives (g) may be used alone or in combination of two or more in any ratio.

[0272] <(h) Solvent> The coating resin composition may further contain a (h) solvent as a volatile component in addition to the non-volatile components (a) to (c), (e), and (g) described above. The (h) solvent may be one of the same range as the (G) solvent that may be contained in the liquid resin composition. One type of (h) solvent may be used alone, or two or more types may be used in combination.

[0273] The amount of (h) solvent contained in the coating resin composition may be 0% by mass or more than 0% by mass, but is preferably 0% by mass to 20% by mass, more preferably 0% by mass to 10% by mass, and even more preferably 0% by mass to 5% by mass, relative to 100% by mass of the non-volatile components of the coating resin composition. Of these, it is particularly preferred that the coating resin composition does not contain a solvent.

[0274] The thickness of the coating resin composition layer is not particularly limited, but from the viewpoint of thinning, it is preferably 600 μm or less, more preferably 500 μm or less, and even more preferably 400 μm or less. The lower limit of the thickness may be, for example, 5 μm or more, 10 μm or more, etc. Usually, the second cured layer obtained by curing the coating resin composition layer also has a thickness within the above range.

[0275] <Method for producing coated resin composition layer> The coated resin composition layer can be produced, for example, by a method including applying the coating resin composition to a support surface. The coated resin composition layer can also be produced, for example, by a method including, in this order, preparing a resin varnish in which the coating resin composition is dissolved or dispersed in a solvent, applying the resin varnish to the support surface, and drying the applied resin varnish. The support surface can be, for example, the surface of a support that the resin sheet can be provided with. The solvent can also be the solvent (h) described above.

[0276] Coating can be carried out using a coating device such as a die coater. Drying can be carried out by drying methods such as heating and hot air blowing. Drying conditions are not particularly limited, but drying is carried out so that the amount of solvent in the coating resin composition layer is preferably 10% by mass or less, more preferably 5% by mass or less. Although this may vary depending on the boiling point of the solvent in the resin varnish, for example, when a resin varnish containing 30% by mass to 60% by mass of solvent is used, the coating resin composition layer can be formed by drying at 50°C to 150°C for 3 to 10 minutes.

[0277] <Characteristics of the cured product of the coating resin composition> In the above-described method for producing a component-embedded substrate, the second cured layer is formed from the cured product of the coating resin composition (coating resin composition layer). Therefore, the second cured layer usually contains the cured product of the coating resin composition, and preferably contains only the cured product of the coating resin composition. Therefore, the second cured layer usually has the same properties as the cured product of the coating resin composition. From the perspective of appropriately controlling the properties of the second cured layer to obtain a high-quality component-embedded substrate, it is preferable that the cured product of the coating resin composition have appropriate properties. Specifically, it is preferable that the cured product of the coating resin composition have the following properties.

[0278] Average linear thermal expansion coefficient α of the cured product of the coating resin composition at 25°C Ｓ is preferably 3 ppm / °C or more, more preferably 5 ppm / °C or more, even more preferably 8 ppm / °C or more, and is preferably 60 ppm / °C or less, more preferably 55 ppm / °C or less, even more preferably 50 ppm / °C or less. The average linear thermal expansion coefficient can be measured by the method described in the examples below.

[0279] The average linear thermal expansion coefficient of the cured resin composition layer (coating resin composition layer) is α Ｓ The average linear thermal expansion coefficient of the cured product of the liquid resin composition is α Ｌ Then, α Ｓ / α Ｌ is preferably greater than 0.6, more preferably 0.65 or more, and even more preferably 0.7 or more. The upper limit is preferably 7.5 or less, more preferably 7.3 or less, and even more preferably 7.1 or less. Ｓ / α Ｌ By adjusting the elastic modulus of the cured product of the liquid resin composition and the coating resin composition so that it falls within this range, it is possible to suppress delamination between the part in the cavity and the first cured layer, and it is also possible to suppress delamination between the first cured layer and the second cured layer.

[0280] Elastic modulus E of the cured product of the coating resin composition at 25°C Ｓ is preferably 1 GPa or more, more preferably 1.5 GPa or more, even more preferably 3 GPa or more, and is preferably 25 GPa or less, more preferably 20 GPa or less, even more preferably 15 GPa or less. Ｓ can be measured by the method described in the Examples below.

[0281] The elastic modulus of the cured resin composition layer at 25°C is E Ｓ The elastic modulus of the cured product of the liquid resin composition at 25°C is E Ｌ When this is done, E Ｓ / E Ｌ is preferably 0.3 or more, more preferably 0.31 or more, even more preferably 0.32 or more, 0.35 or more, or 0.4 or more. The upper limit is preferably less than 2, more preferably 1.9 or less, even more preferably 1.88 or less, 1.7 or less, or 1.5 or less. Ｓ / E ＬBy adjusting the elastic modulus of the cured product of the liquid resin composition and the coating resin composition so that it falls within this range, it is possible to suppress delamination between the part in the cavity and the first cured layer, and it is also possible to suppress delamination between the first cured layer and the second cured layer.

[0282] [Resin Sheet] The above-described coated resin composition layer is usually prepared as a part of a resin sheet. This resin sheet includes a support and a coated resin composition layer formed on this support. The coated resin composition layer is as described above.

[0283] Examples of the support include a film made of a plastic material, a metal foil, and release paper. Among these, a support containing a metal foil is preferred, and it is more preferred to use a metal foil as the support. Metal foil typically tends to prevent air and volatile components from passing through. Therefore, in conventional manufacturing methods in which a resin sheet having a metal foil support is laminated onto a cavity substrate to fill the cavity, voids tend to occur in the manufactured component-embedded substrate. In contrast, in the manufacturing method according to the present embodiment, a support is not used, and the resin sheet is laminated after the cavity is filled with a liquid resin composition. Therefore, even if the support contains metal foil, the generation of voids can be effectively suppressed. Therefore, from the viewpoint of effectively utilizing the advantage of being able to effectively suppress voids even in manufacturing methods using metal foil, which tended to generate voids in conventional technology, it is preferable to employ a support containing metal foil, as described above.

[0284] When a film made of a plastic material is used as the support, examples of the plastic material include polyesters such as polyethylene terephthalate (hereinafter sometimes abbreviated as "PET") and polyethylene naphthalate (hereinafter sometimes abbreviated as "PEN"), polycarbonate (hereinafter sometimes abbreviated as "PC"), acrylic polymers such as polymethyl methacrylate (hereinafter sometimes abbreviated as "PMMA"), cyclic polyolefins, triacetyl cellulose (hereinafter sometimes abbreviated as "TAC"), polyether sulfide (hereinafter sometimes abbreviated as "PES"), polyether ketone, polyimide, etc. Among these, polyethylene terephthalate and polyethylene naphthalate are preferred, and inexpensive polyethylene terephthalate is particularly preferred.

[0285] When a metal foil is used as the support, examples of the metal foil include copper foil and aluminum foil. Of these, copper foil is preferred. As the copper foil, a foil made of a single metal, copper, or an alloy of copper and another metal (e.g., tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) may be used.

[0286] The metal foil may have a single layer structure or a multi-layer structure in which two or more single metal layers or alloy layers made of different types of metals or alloys are laminated. Examples of multi-layer metal foils include metal foils containing a carrier metal foil and an ultra-thin metal foil bonded to the carrier metal foil. This multi-layer metal foil may include a release layer between the carrier metal foil and the ultra-thin metal foil, which enables the carrier metal foil and the ultra-thin metal foil to be peeled off. Examples of the release layer include an alloy layer of an element selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, and P; an organic coating, etc. When a multi-layer metal foil is used as the support, the coating resin composition layer is usually provided on the ultra-thin metal foil.

[0287] The method for producing the metal foil is not particularly limited, but examples thereof include electrolysis, rolling, etc. Examples of commercially available metal foils include "HLP foil" and "JXUT-III foil" manufactured by JX Nippon Mining & Metals Corporation, and "Microthin MT-Ex copper foil," "TP-III foil," "MLS-G foil," "MW-G foil," and "HS-VSP foil" manufactured by Mitsui Mining & Smelting Co., Ltd.

[0288] The surface of the support that is to be bonded to the coating resin composition layer may be subjected to a matte treatment, a corona treatment, an antistatic treatment or the like.

[0289] The support may be a support with a release layer, which has a release layer on the surface that bonds with the coating resin composition layer. Examples of the release agent used in the release layer of the support with a release layer include one or more release agents selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins. Examples of commercially available release agents include alkyd resin-based release agents such as "SK-1," "AL-5," and "AL-7" manufactured by Lintec Corporation. Examples of support with a release layer include "Lumirror T60" manufactured by Toray Industries, Inc.; "Purex" manufactured by Teijin Limited; and "Uni-Peel" manufactured by Unitika Ltd.

[0290] The thickness of the support is preferably 1 μm or more, more preferably 5 μm or more, even more preferably 10 μm or more, and is preferably 75 μm or less, more preferably 60 μm or less, even more preferably 50 μm or less, particularly preferably 40 μm or less. When a multilayer metal foil is used as the support, it is preferable that the thickness of the entire metal foil is in this range, and the thickness of the ultrathin metal foil may be, for example, in the range of 0.1 μm to 10 μm.

[0291] The resin sheet may further include an optional layer in combination with the support and the coated resin composition layer, if necessary. Examples of optional layers include a protective film provided on the surface of the coated resin composition layer that is not bonded to the support (i.e., the surface opposite the support). The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. When a protective film is provided, adhesion of dust and scratches to the surface of the coated resin composition layer can be suppressed. When the resin sheet includes a protective film, the resin sheet can usually be used by peeling off the protective film. Furthermore, the resin sheet can be stored by being wound into a roll.

[0292] The resin sheet can be produced, for example, by a method including forming a coating resin composition layer on a support. The coating resin composition layer can be formed by the above-mentioned method for producing a coating resin composition layer.

[0293] [Set Comprising a Liquid Resin Composition and a Resin Sheet] A set according to one embodiment of the present invention comprises a liquid resin composition and a resin sheet having a coating resin composition layer. The liquid resin composition and the resin sheet may be those described above. Therefore, in this set, it is preferable that the liquid resin composition or its cured product and the coating resin composition or its cured product satisfy the relationship described above. Therefore, the elastic modulus E of the cured product of the liquid resin composition Ｌ and the elastic modulus E of the cured product of the coating resin composition Ｓ the mean linear thermal expansion coefficient α of the cured product of the liquid resin composition Ｌ and the average linear thermal expansion coefficient α of the cured product of the coating resin composition Ｓ It is preferable that the relationships such as the relationship between the number of layers and the thickness of the substrate satisfy the above-mentioned preferable conditions. This set can be suitably used in the above-mentioned method for manufacturing a component-embedded substrate.

[0294] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to the following examples. In the following description, "parts" and "%" representing amounts are based on mass unless otherwise specified. Furthermore, the operations described below were performed in an environment of room temperature and normal pressure (25°C, 1 atm) unless otherwise specified.

[0295] <Inorganic fillers used> Inorganic filler 1: High amorphous silica A (D) obtained by using crystalline silica as a raw material and performing the melting step twice in the melting method. １０ : 0.9 μm, D ５０ : 7.8 μm, D ９０ :15.2μm, specific surface area 3.3m ２ / g) was surface-treated with 0.5% of a silane coupling agent "KBM4803" manufactured by Shin-Etsu Chemical Co., Ltd. Inorganic filler 2: High amorphous silica A (D １０ : 0.9 μm, D ５０ : 7.8 μm, D ９０ :15.2μm, specific surface area 3.3m ２ / g) was surface-treated with 0.4% of a silane coupling agent "KBM403" manufactured by Shin-Etsu Chemical Co., Ltd. Inorganic filler 3: silica particles, D ５０ :1.5μm, specific surface area 7.0m ２ / g: Surface treated with silane coupling agent "KBM573" manufactured by Shin-Etsu Chemical Co., Ltd. Inorganic filler 4: silica particles, D ５０ :0.5μm, specific surface area 6.0m ２ / g: Surface treated with silane coupling agent "KBM573" manufactured by Shin-Etsu Chemical Co., Ltd. RY-200: "RY-200" manufactured by Nippon Aerosil Co., Ltd.

[0296] [Method for measuring physical properties of liquid resin composition and coating resin composition (resin composition)] <Method for measuring viscosity> The viscosity of the liquid resin composition was measured at a temperature of 25°C and a rotation speed of 5 rpm using an E-type viscometer RE-80U (manufactured by Toki Sangyo Co., Ltd.) with a cone rotor of 3° x R9.7, calibrated with viscosity calibration standard fluid JS52000. The viscosity was evaluated according to the following evaluation criteria. ◯: 30 Pa s or more and 300 Pa s or less ×: Viscosity outside the above range

[0297] <Methods for measuring average linear thermal expansion coefficient (thermal expansion coefficient) and elastic modulus> (1) Preparation of cured product for evaluation: A polyethylene terephthalate film ("501010" manufactured by Lintec Corporation, 38 μm thick, 240 mm square, hereinafter sometimes referred to as "first release PET film") with a release treatment applied to one side was prepared. This first release PET film was placed on a glass cloth-based epoxy resin double-sided copper-clad laminate ("R5715ES" manufactured by Panasonic Electric Works, Ltd., 0.7 mm thick, 255 mm square) so that the untreated side of the first release PET film was in contact with the glass cloth-based epoxy resin double-sided copper-clad laminate. The four edges of the first release film were fixed with polyimide adhesive tape (10 mm wide).

[0298] Next, a polyethylene terephthalate film ("Lumirror T6AM" manufactured by Toray Industries, Inc., thickness 38 μm, softening point 130°C, hereinafter sometimes referred to as "second release PET film") that had been subjected to a release treatment with an alkyd resin-based release agent ("AL-5" manufactured by Lintec Corporation) was prepared as a support. The resin composition was uniformly applied onto the second release PET film using a die coater so that the thickness of the resin composition layer after drying would be 70 μm, and the film was dried at 80°C to 160°C for 5 minutes to obtain a resin composition layer on the second release PET film.

[0299] The obtained resin composition layer was laminated to the center of a first release PET film using a batch-type vacuum pressure laminator (a two-stage build-up laminator "CVP700" manufactured by Nichigo-Morton Co., Ltd.). This lamination process was performed so that the resin composition layer was in contact with the release surface of the first release PET film. This lamination process was performed by reducing the pressure for 30 seconds to 13 hPa or less, and then pressing at 100 ° C. and a pressure of 0.74 MPa for 30 seconds.

[0300] Next, the second release PET film serving as a support was peeled off. The resin composition layer was then thermally cured at 190°C for 90 minutes to obtain a cured resin composition layer. After thermal curing, the polyimide adhesive tape was peeled off, and the cured product was removed from the glass cloth-based epoxy resin double-sided copper-clad laminate. The first release PET film was then peeled off from the cured product to obtain a sheet-like cured product. This sheet-like cured product is sometimes referred to as a "cured product for evaluation."

[0301] (2) Measurement of the Average Coefficient of Linear Thermal Expansion The cured product for evaluation was cut into a length of approximately 15 mm and a width of approximately 5 mm to obtain a test specimen. Thermomechanical analysis was performed using a thermomechanical analyzer (Rigaku Corporation, "Thermo Plus TMA8310") by the tensile load method. Specifically, after mounting the test specimen in the analyzer, measurements were performed twice consecutively under the measurement conditions of a load of 1 g and a heating rate of 5°C / min. The first measurement was performed by raising the temperature to 200°C, and the second measurement was performed by raising the temperature to 260°C. In the second measurement, the average coefficient of linear thermal expansion (CTE) from 25°C to 150°C was calculated.

[0302] (3) Measurement of Elastic Modulus The cured product for evaluation was cut into a No. 1 dumbbell-shaped test piece to obtain a test piece. The tensile strength of the test piece was measured using a tensile tester ("RTC-1250A" manufactured by Orientec Co., Ltd.) to determine the elastic modulus and elongation at break at 25°C. The measurement was carried out in accordance with JIS K7127. This measurement of elastic modulus was carried out three times, and the average values ​​are shown in the table.

[0303] Synthesis Example 1. Production of Elastomer A: 69 g of bifunctional hydroxy-terminated polybutadiene ("G-3000" manufactured by Nippon Soda Co., Ltd., number average molecular weight = 3000, hydroxy group equivalent = 1800 g / eq.), 40 g of an aromatic hydrocarbon mixed solvent ("IPZOL 150" manufactured by Idemitsu Petrochemical Co., Ltd.), and 0.005 g of dibutyltin laurate were placed in a reaction vessel and mixed to dissolve uniformly. Once uniform, the mixture was heated to 60°C, and 8 g of isophorone diisocyanate ("IPDI" manufactured by Evonik Degussa Japan Co., Ltd., isocyanate group equivalent = 113 g / eq.) was added with further stirring, and the reaction was carried out for approximately 3 hours.

[0304] Next, 23 g of cresol novolak resin (KA-1160 manufactured by DIC Corporation, hydroxyl group equivalent weight = 117 g / eq.) and 80 g of ethyl diglycol acetate (manufactured by Daicel Corporation) were added to the reaction mixture, and the mixture was heated to 150°C with stirring and reacted for about 10 hours. －１The disappearance of the NCO peak was confirmed. The disappearance of the NCO peak was considered to be the end point of the reaction, and the reaction mixture was cooled to room temperature. The reaction mixture was then filtered through a 100-mesh filter cloth to obtain Elastomer A having a butadiene structure and phenolic hydroxyl groups (phenolic hydroxyl group-containing butadiene resin: non-volatile components 45% by mass). Elastomer A had a number average molecular weight of 5,900 and a glass transition temperature of -7°C.

[0305] [Preparation Example 1. Preparation of Liquid Resin Composition 1] 2.5 parts of a liquid epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture (mass ratio) of bisphenol A epoxy resin and bisphenol F epoxy resin, epoxy equivalent: 169 g / eq.), 4.5 parts of a liquid epoxy resin ("ZX1658" manufactured by Nippon Steel Chemical & Material Co., Ltd., liquid 1,4-glycidylcyclohexane epoxy resin, epoxy equivalent: 135 g / eq.), 2 parts of a liquid epoxy resin ("MX-153" manufactured by Kaneka Corporation, a bisphenol A epoxy resin containing an organic filler having a core-shell structure, epoxy equivalent: 270 g / eq.), 20 parts of Inorganic Filler 1, 40 parts of Inorganic Filler 2, and 0.5 parts of an imidazole curing accelerator ("2MZA-PW" manufactured by Shikoku Chemicals Corporation) were uniformly dispersed using a three-roll mill to obtain Liquid Resin Composition 1. The physical properties of the obtained liquid resin composition 1 were measured by the above-mentioned measuring methods.

[0306] [Preparation Example 2. Production of Liquid Resin Composition 2] In Preparation Example 1, 1) the amount of Inorganic Filler 1 was changed from 20 parts to 40 parts, and 2) the amount of Inorganic Filler 2 was changed from 40 parts to 20 parts. Except for the above, liquid resin composition 2 was produced in the same manner as Preparation Example 1. The physical properties of the obtained liquid resin composition 2 were measured using the measurement methods described above.

[0307] Preparation Example 3. Production of Liquid Resin Composition 3 3 parts of a liquid epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture (mass ratio) of bisphenol A epoxy resin and bisphenol F epoxy resin, epoxy equivalent: 169 g / eq.), 2.5 parts of a liquid epoxy resin ("EX-201" manufactured by Nagase ChemteX Corporation, cyclic aliphatic glycidyl ether, epoxy equivalent: 117 g / eq.), 0.1 parts of an inorganic filler ("RY-200" manufactured by Nippon Aerosil Co., Ltd.), 235 parts of an inorganic filler, and 0.5 parts of an imidazole curing accelerator ("2MZA-PW" manufactured by Shikoku Chemicals Corporation) were uniformly dispersed using a three-roll mill to obtain Liquid Resin Composition 3. The physical properties of the obtained Liquid Resin Composition 3 were measured using the measurement methods described above.

[0308] Preparation Example 4. Production of Liquid Resin Composition 4 3 parts of a liquid epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture (mass ratio) of bisphenol A epoxy resin and bisphenol F epoxy resin, epoxy equivalent: 169 g / eq.), 2 parts of a liquid epoxy resin ("ZX1658" manufactured by Nippon Steel Chemical & Material Co., Ltd., liquid 1,4-glycidylcyclohexane epoxy resin, epoxy equivalent: 135 g / eq.), 5 parts of a liquid epoxy resin ("EX-201" manufactured by Nagase ChemteX Corporation, cyclic aliphatic glycidyl ether, epoxy equivalent: 117 g / eq.), 2 parts of a liquid epoxy resin ("MX-153" manufactured by Kaneka Corporation, a bisphenol A epoxy resin containing an organic filler having a core-shell structure, epoxy equivalent: 270 g / eq.), 2 parts of an inorganic filler, 100 parts of the hydroxybenzoate and 1 part of an imidazole curing accelerator ("2MZA-PW" manufactured by Shikoku Chemicals Corporation) were uniformly dispersed using a triple roll to obtain a liquid resin composition 4. The physical properties of the obtained liquid resin composition 4 were measured by the above-mentioned measurement methods.

[0309] [Preparation Example 5. Production of Liquid Resin Composition 5] 5 parts of liquid epoxy resin (Nippon Steel Chemical & Material Co., Ltd.'s "ZX1059", a 1:1 mixture (mass ratio) of bisphenol A epoxy resin and bisphenol F epoxy resin, epoxy equivalent: 169 g / eq.), 2 parts of liquid epoxy resin (Nippon Steel Chemical & Material Co., Ltd.'s "ZX1658", liquid 1,4-glycidylcyclohexane epoxy resin, epoxy equivalent: 135 g / eq.), 3 parts of liquid epoxy resin (Mitsubishi Chemical Corporation's "630LSD", glycidylamine epoxy resin, epoxy equivalent: 98 g / eq.), 2 parts of liquid epoxy resin (Kaneka Corporation's "MX-153", bisphenol A epoxy resin containing an organic filler having a core-shell structure, epoxy equivalent: 270 g / eq.), 0.1 parts of inorganic filler (Nippon Aerosil Co., Ltd.'s "RY-200"), 2 parts of inorganic filler 55 parts of PEG-404, 0.3 parts of a silane coupling agent ("KBM-403" manufactured by Shin-Etsu Chemical Co., Ltd.), and 1 part of an imidazole-based curing accelerator ("2MZA-PW" manufactured by Shikoku Chemical Industry Co., Ltd.) were uniformly dispersed using a triple roll mill to obtain Liquid Resin Composition 5. The physical properties of the obtained Liquid Resin Composition 5 were measured by the above-mentioned measurement methods.

[0310] [Preparation Example 6. Production of Liquid Resin Composition 6] In Preparation Example 5, 1) the amount of Inorganic Filler 2 was changed from 55 parts to 20 parts, and 2) 5 parts of Inorganic Filler 1 was further used. Except for the above, the same procedure as in Preparation Example 5 was repeated to obtain Liquid Resin Composition 6. The physical properties of the obtained Liquid Resin Composition 6 were measured using the measurement methods described above.

[0311] [Preparation Example 7. Production of Liquid Resin Composition 7] 5 parts of liquid epoxy resin (Nippon Steel Chemical & Material Co., Ltd. "ZX1059", a 1:1 mixture (mass ratio) of bisphenol A type epoxy resin and bisphenol F type epoxy resin, epoxy equivalent: 169 g / eq.), 3 parts of liquid epoxy resin (Mitsubishi Chemical Corporation "YX7400", epoxy equivalent: 440 g / eq.), 2 parts of liquid epoxy resin (Daicel Corporation "Celloxide 2081", an alicyclic epoxy resin having an ester skeleton, epoxy equivalent: 200 g / eq.), 7 parts of liquid epoxy resin (Mitsubishi Chemical Corporation "630LSD", a glycidylamine type epoxy resin, epoxy equivalent: 98 g / eq.), 4 parts of liquid epoxy resin (DIC Corporation "HP-4032SS", a naphthalene type epoxy resin, epoxy equivalent: 144 g / eq.), 3 parts of inorganic filler 3 30 parts of a polymer resin ("Pluronic L-44" manufactured by ADEKA Corporation, a polyether skeleton-containing compound) 2.5 parts, 0.1 parts of a silane coupling agent ("KBM-403" manufactured by Shin-Etsu Chemical Co., Ltd.), and 0.4 parts of diaminodiphenyl sulfone (DDS) were uniformly dispersed using a three-roll mill to obtain Liquid Resin Composition 7. The physical properties of the obtained Liquid Resin Composition 7 were measured using the above-mentioned measurement methods.

[0312] Preparation Example 8. Production of Liquid Resin Composition 8 In Preparation Example 1, 0.4 parts of a dispersant ("PB-881" manufactured by Ajinomoto Fine-Techno Co., Inc., a dispersant containing an alkylene skeleton and a polyester skeleton in the main chain, having amino groups as functional groups, and hydroxyl groups at the terminals) was further used. Except for the above, the same procedure as in Preparation Example 1 was repeated to obtain Liquid Resin Composition 8. The physical properties of the obtained Liquid Resin Composition 8 were measured using the measurement methods described above.

[0313] Preparation Example 9. Production of Liquid Resin Composition 9 In Preparation Example 1, 0.4 parts of a dispersant (SC-1015F, manufactured by NOF Corporation, a dispersant containing an alkylene skeleton and a polyether skeleton in the main chain, having a carboxyl group as a functional group, and having a hydrogen atom at the end) was further used. The physical properties of the obtained Liquid Resin Composition 9 were measured using the measurement methods described above.

[0314] Preparation Example 10. Production of Liquid Resin Composition 10 In Preparation Example 1, 0.4 parts of a dispersant ("PB-821" manufactured by Ajinomoto Fine-Techno Co., Inc., a dispersant containing an alkylene skeleton and a polyester skeleton in the main chain, having amino groups as functional groups, and terminal hydroxyl groups and carboxylic acid residues) was further used. The physical properties of the obtained liquid resin composition 10 were measured using the measurement methods described above.

[0315] Preparation Example 11. Production of Liquid Resin Composition 11 In Preparation Example 1, 0.4 parts of a dispersant ("ED-400" manufactured by Kusumoto Chemicals Co., Ltd., a dispersant containing a polyether skeleton in the main chain and having an amino group as a functional group) was further used. The physical properties of the obtained liquid resin composition 11 were measured by the measurement methods described above.

[0316] Preparation Example 12. Production of Liquid Resin Composition 12 In Preparation Example 1, 0.6 parts of a dispersant (SC-1015F, manufactured by NOF Corporation, a dispersant containing an alkylene skeleton and a polyether skeleton in the main chain, having a carboxyl group as a functional group, and having a hydrogen atom at the end) was further used. The physical properties of the obtained liquid resin composition 12 were measured using the measurement methods described above.

[0317] Preparation Example 13. Production of Liquid Resin Composition 13 In Preparation Example 1, 0.8 parts of a dispersant (SC-1015F, manufactured by NOF Corporation, a dispersant containing an alkylene skeleton and a polyether skeleton in the main chain, having a carboxyl group as a functional group, and having a hydrogen atom at the end) was further used. The physical properties of the obtained liquid resin composition 13 were measured using the measurement methods described above.

[0318] Preparation Example 14: Production of Coating Resin Composition 14 for Resin Sheet 10 parts of a liquid epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture (mass ratio) of bisphenol A epoxy resin and bisphenol F epoxy resin, epoxy equivalent: 169 g / eq.), 20 parts of a biphenyl epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: 269 g / eq.), 5 parts of a naphthalene-type tetrafunctional epoxy resin ("HP-4700" manufactured by DIC Corporation, epoxy equivalent: 165 g / eq.), 1 part of a triazine skeleton-containing cresol novolac curing agent (DIC 5 parts of "LA-3018-50P" manufactured by Company C, hydroxyl group equivalent 151 g / eq., 50% solids solution in 2-methoxypropanol), 15 parts of active ester curing agent ("HPC8000-65T" manufactured by DIC Corporation, active group equivalent approximately 223 g / eq., 65% solids solution in toluene), 0.1 parts of dimethylaminopyridine (DMAP), 5 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, 1:1 solution of cyclohexanone:methyl ethyl ketone (MEK) with a solids content of 30% by weight), and 140 parts of inorganic filler 4 were uniformly dispersed in a mixer to obtain a coating resin composition 14 for a resin sheet. The physical properties of the obtained coating resin composition 14 were measured using the measurement methods described above.

[0319] Preparation Example 15: Production of Coating Resin Composition 15 for Resin Sheet 10 parts of a liquid epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture (mass ratio) of bisphenol A epoxy resin and bisphenol F epoxy resin, epoxy equivalent: 169 g / eq.), 10 parts of a biphenyl epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: 269 g / eq.), 30 parts of a naphthalene-type tetrafunctional epoxy resin ("HP-4700" manufactured by DIC Corporation, epoxy equivalent: 165 g / eq.), 5 parts of a triazine skeleton-containing cresol novolac curing agent (DIC 9 parts of naphthol-based curing agent ("SN-485-65M" manufactured by Nippon Steel Chemical & Material Co., Ltd., hydroxyl equivalent 215 g / eq., MEK solution with a solids content of 65%), 0.1 parts of dimethylaminopyridine (DMAP), 5 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical Corporation, a 1:1 solution of cyclohexanone:methyl ethyl ketone (MEK) with a solids content of 30% by mass), and 230 parts of inorganic filler 3 were uniformly dispersed in a mixer to obtain a coating resin composition 15 for a resin sheet. The physical properties of the obtained coating resin composition 15 were measured using the measurement methods described above.

[0320] Preparation Example 16: Production of coating resin composition 16 for resin sheet A liquid epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture (mass ratio) of bisphenol A epoxy resin and bisphenol F epoxy resin, epoxy equivalent: 169 g / eq.) of 15 parts, a biphenyl epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: 269 g / eq.) of 30 parts, a triazine skeleton-containing cresol novolak curing agent ("LA-3018-50P" manufactured by DIC Corporation, hydroxyl group equivalent: 151 g / eq.) of 10 parts, a hydroxyl group equivalent: 151 g / eq. g / eq., 50% solids solution in 2-methoxypropanol), 9 parts of an active ester curing agent (DIC Corporation's "HPC8000-65T," active group equivalent weight approximately 223 g / eq., 65% solids solution in toluene), 18 parts of an active ester curing agent, 0.1 parts of dimethylaminopyridine (DMAP), 5 parts of a phenoxy resin (Mitsubishi Chemical Corporation's "YX7553BH30," a 1:1 solution of cyclohexanone:methyl ethyl ketone (MEK) with a solids content of 30% by weight), and 470 parts of an inorganic filler were uniformly dispersed in a mixer to obtain a coating resin composition 16 for a resin sheet. The physical properties of the obtained coating resin composition 16 were measured using the measurement methods described above.

[0321] [Preparation Example 17.

[0111] Preparation of coating resin composition 17 for resin sheet] 10 parts of liquid epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture (mass ratio) of bisphenol A type epoxy resin and bisphenol F type epoxy resin, epoxy equivalent: 169 g / eq.), 15 parts of liquid epoxy resin ("YX7400" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: 440 g / eq.), 10 parts of naphthalene type tetrafunctional epoxy resin ("HP-4700" manufactured by DIC Corporation, epoxy equivalent: 165 g / eq.), 5 parts of naphthol-based curing agent ("SN-485-65M" manufactured by Nippon Steel Chemical & Material Co., Ltd., hydroxyl group equivalent: 215 g / eq., MEK solution with a solid content of 65%), 0.1 parts of dimethylaminopyridine (DMAP), 10 parts of elastomer A synthesized in Synthesis Example 1, and inorganic filler 3 150 parts of the mixture was uniformly dispersed in a mixer to obtain a coating resin composition for a resin sheet 17. The physical properties of the obtained coating resin composition 17 were measured by the above-mentioned measuring methods.

[0322] Preparation Example 18: Production of Coating Resin Composition 18 for Resin Sheet A liquid epoxy resin ("ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd., a 1:1 mixture (mass ratio) of bisphenol A epoxy resin and bisphenol F epoxy resin, epoxy equivalent: 169 g / eq.) 5 parts, a biphenyl epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent: 269 g / eq.) 5 parts, a triazine skeleton-containing cresol novolak curing agent ("LA-3018-50P" manufactured by DIC Corporation, hydroxyl group equivalent: 151 g / eq.) 1 part, and a hydroxyl group equivalent: 151 g / eq. eq., 50% solids solution in 2-methoxypropanol), 5 parts of a naphthol-based curing agent ("SN-485-65M" manufactured by Nippon Steel Chemical & Material Co., Ltd., hydroxyl group equivalent 215 g / eq., 65% solids solution in MEK), 0.1 parts of dimethylaminopyridine (DMAP), 5 parts of a phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical, 1:1 solution of cyclohexanone:methyl ethyl ketone (MEK) with a solids content of 30% by mass), and 10 parts of inorganic filler 4 were uniformly dispersed in a mixer to obtain a coating resin composition 18 for a resin sheet. The physical properties of the obtained coating resin composition 18 were measured using the measurement methods described above.

[0323] *1: Indicates the content when the non-volatile components are 100% by mass. *2: Indicates the content when the non-volatile components are 100% by volume.

[0324] Example 1 <Preparation of Evaluation Substrate and Test Substrate> (1) Preparation of Cavity Substrate (Step (I)): Figure 11 is a schematic plan view showing the cavity substrate as viewed from the thickness direction to explain the position of the cavities formed in this example. As shown in Figure 11, 20 cavities 211-214, 221-224, 231-234, 241-244, and 251-254 were formed in a copper-clad laminate ("MCL-E-705G" manufactured by Resonac, 250 mm long, 250 mm wide, and 1.4 mm thick) serving as substrate 200. Specifically, four cavities 211-214 were formed in center portion 210 of substrate 200. The opening of each of cavities 211-214 was rectangular, measuring 1.6 mm long and 2.35 mm wide. The spacing between these cavities 211 to 214 was 1 mm. Furthermore, four cavities 221 to 224, 231 to 234, 241 to 244, and 251 to 254 were formed in each of four corners 220, 230, 240, and 250, which were 75 mm apart vertically and horizontally from the central portion 210, just like in the central portion 210.

[0325] An adhesive film ("PFDKE-1525TT" manufactured by Arisawa Manufacturing Co., Ltd.) was attached as a temporary adhesive to one surface of the substrate on which the cavity was formed, to close one opening of the cavity.

[0326] (2) Mounting of Components (Step (II)): A silicon chip (length 0.95 mm, width 1.75 mm, thickness 785 μm) was mounted as a component in each cavity of the substrate to obtain an intermediate substrate.

[0327] (3) Filling and curing of liquid resin composition (printing, step (III) and step (IV)): A metal mask was prepared as a mask. The metal mask had a thickness of 100 μm and had openings formed as hollow holes. The planar shape of the openings was the same as that of the cavities.

[0328] Using the mask described above, printing was performed on a substrate having a cavity formed therein, using a semi-automatic vacuum hole filling device equipped with a CCD camera ("SVM-6151IP" manufactured by Ceria Corporation) in the following manner.

[0329] A mask was placed on one side of the substrate where the cavities were formed, such that the openings of the mask communicated with the plurality of cavities in the substrate where the cavities were formed.

[0330] Thereafter, the liquid resin composition 1 prepared in Preparation Example 1 was supplied to the surface of the mask opposite to the substrate on which the cavities were formed.

[0331] A rubber squeegee (rubber hardness 80 degrees) made of rubber as the elastic material was moved along the surface of the mask to print the liquid resin composition 1. The attack angle of the first squeegee was 10°, the printing pressure was 500 N, the printing speed was 20 mm / sec, the push-in was 1.5 mm, and the vacuum level was 100 Pa. The first squeegee moved across the opening of the mask while maintaining a paste pool of the liquid resin composition 1 ahead of the moving direction of the first squeegee. This operation swept the first squeegee, filling the cavity with the liquid resin composition 1.

[0332] Thereafter, a metal squeegee (material thickness 150 μm, blade thickness 70 μm) made of SUS (stainless steel) as a rigid material was moved along the surface of the mask to print the liquid resin composition. The attack angle of the second squeegee was 75°, the printing pressure was 120 N, the printing speed was 60 mm / sec, the push-in depth was 0.5 mm, and the vacuum level was 100 Pa. The second squeegee moved across the opening of the mask while maintaining a paste pool of liquid resin composition 1 ahead of the direction of movement of the second squeegee. This operation swept the second squeegee, filling the cavity with liquid resin composition 1.

[0333] The printing resulted in a filled substrate in which a liquid resin composition layer was filled into the cavity. This filled substrate was heated at 130°C for 30 minutes and then at 180°C for 30 minutes. This heating thermally cured the liquid resin composition layer to form a first cured layer, resulting in an evaluation substrate corresponding to a circuit board. In the evaluation substrate obtained, the silicon chip in the cavity was embedded in the cured liquid resin composition that had filled the cavity.

[0334] (4) Formation and curing of resin composition layer (steps (V) and (VI)): A polyethylene terephthalate film ("Lumirror T6AM" manufactured by Toray Industries, Inc., thickness 38 μm, softening point 130°C) that had been subjected to a release treatment with an alkyd resin-based release agent ("AL-5" manufactured by Lintec Corporation) was prepared as a support. The coating resin composition 14 prepared in Preparation Example 14 was uniformly applied to the support using a die coater so that the thickness of the resin composition layer after drying would be 25 μm, and the resulting film was dried at 80°C to 160°C for 5 minutes to obtain a resin composition layer on the support. Next, a polypropylene film ("Alphan MA-430" manufactured by Oji F-Tex Co., Ltd., thickness 20 μm) was laminated as a protective film on the side of the resin composition layer that was not bonded to the support so as to be bonded to the resin composition layer, thereby obtaining a resin sheet.

[0335] After peeling off the protective film, a batch-type vacuum pressure laminator (Nikko Materials Co., Ltd., two-stage build-up laminator "CVP700") was used to laminate the liquid resin composition layer onto both sides of the evaluation substrate so that it was bonded to the evaluation substrate. This lamination was performed by reducing the pressure for 30 seconds to 13 hPa or less, and then pressing at a temperature of 100 ° C and a pressure of 0.74 MPa for 30 seconds. The laminated resin sheet was then heat-pressed at atmospheric pressure, 100 ° C, and a pressure of 0.5 MPa for 60 seconds to smooth it. The support was then peeled off and placed in an oven at 180 ° C and heated for 60 minutes. The resulting substrate is referred to as the "test substrate."

[0336] [Example 2] An evaluation substrate and a test substrate were manufactured in the same manner as in Example 1, except that liquid resin composition 2 was used instead of liquid resin composition 1 and coating resin composition 15 was used instead of coating resin composition 14.

[0337] [Example 3] An evaluation substrate and a test substrate were manufactured in the same manner as in Example 1, except that liquid resin composition 3 was used instead of liquid resin composition 1 and coating resin composition 16 was used instead of coating resin composition 14.

[0338] [Example 4] Evaluation substrates and test substrates were manufactured in the same manner as in Example 1, except that liquid resin composition 4 was used instead of liquid resin composition 1 and coating resin composition 18 was used instead of coating resin composition 14.

[0339] [Example 5] Evaluation substrates and test substrates were manufactured in the same manner as in Example 1, except that liquid resin composition 5 was used instead of liquid resin composition 1 and coating resin composition 17 was used instead of coating resin composition 14.

[0340] [Example 6] Evaluation substrates and test substrates were manufactured in the same manner as in Example 1, except that liquid resin composition 5 was used instead of liquid resin composition 1 and coating resin composition 15 was used instead of coating resin composition 14.

[0341] [Example 7] An evaluation substrate and a test substrate were manufactured in the same manner as in Example 1, except that liquid resin composition 6 was used instead of liquid resin composition 1 and coating resin composition 18 was used instead of coating resin composition 14.

[0342] Example 8 An evaluation substrate and a test substrate were produced in the same manner as in Example 1, except that Liquid Resin Composition 8 was used instead of Liquid Resin Composition 1 in Example 1.

[0343] [Example 9] An evaluation substrate and a test substrate were manufactured in the same manner as in Example 1, except that liquid resin composition 9 was used instead of liquid resin composition 1 and coating resin composition 16 was used instead of coating resin composition 14.

[0344] Example 10 An evaluation substrate and a test substrate were produced in the same manner as in Example 1, except that Liquid Resin Composition 10 was used instead of Liquid Resin Composition 1 in Example 1.

[0345] Example 11 An evaluation substrate and a test substrate were produced in the same manner as in Example 1, except that Liquid Resin Composition 11 was used instead of Liquid Resin Composition 1 in Example 1.

[0346] Example 12 An evaluation substrate and a test substrate were produced in the same manner as in Example 1, except that Liquid Resin Composition 12 was used instead of Liquid Resin Composition 1 in Example 1.

[0347] Example 13 An evaluation substrate and a test substrate were produced in the same manner as in Example 1, except that Liquid Resin Composition 13 was used instead of Liquid Resin Composition 1 in Example 1.

[0348] Comparative Example 1 An evaluation substrate and a test substrate were produced in the same manner as in Example 1, except that Liquid Resin Composition 7 was used instead of Liquid Resin Composition 1 in Example 1.

[0349] Comparative Example 2 An evaluation substrate and a test substrate were manufactured in the same manner as in Example 1, except that liquid resin composition 7 was used instead of liquid resin composition 1 and coating resin composition 15 was used instead of coating resin composition 14.

[0350] Comparative Example 3 An evaluation substrate and a test substrate were manufactured in the same manner as in Example 1, except that liquid resin composition 7 was used instead of liquid resin composition 1 and coating resin composition 16 was used instead of coating resin composition 14.

[0351] Comparative Example 4 An evaluation substrate and a test substrate were manufactured in the same manner as in Example 1, except that liquid resin composition 7 was used instead of liquid resin composition 1 and coating resin composition 17 was used instead of coating resin composition 14.

[0352] <Evaluation of Filling Ability> All 20 cavities of the evaluation substrate were observed, and the number of voids that occurred in the cavities was counted. Evaluation was made according to the number of voids using the following criteria: ○: No voids in all 20 cavities ×: Voids present in 1 to 20 cavities

[0353] <Evaluation of Exudation to the Periphery of the Cavity> All 20 cavities in the evaluation substrate were observed, and the maximum amount of exudation of the cured liquid resin composition to the periphery of the cavity was measured using a digital microscope (Keyence Corporation, "VHX-7000"). The maximum exudation amounts for all cavities were averaged and evaluated according to the following criteria: ○: Average value less than 200 μm △: Average value 200 μm or more but less than 1000 μm ×: Average value 1000 μm or more

[0354] <Evaluation of Delamination Between Cured Product of Liquid Resin Composition and Cured Product of Coating Resin Composition> A HAST test was performed in which a test substrate was stored in an environment at a temperature of 130°C and a humidity of 85% RH for 100 hours. The test substrate after the HAST test was observed, and the adhesion (presence or absence of delamination) between the liquid resin composition layer and the coating resin composition was evaluated according to the following criteria: ◯: No peeling at the interface between the first cured layer and the second cured layer. ×: Peeling at the interface between the first cured layer and the second cured layer.

[0355] <Evaluation of Delamination Between the Cured Product of the Liquid Resin Composition and the Part, and Between the Cured Product of the Liquid Resin Composition and the Wall of the Cavity> A test substrate was subjected to HAST, in which it was stored in an environment at a temperature of 130°C and a humidity of 85% RH for 200 hours, and then subjected to a reflow process (maximum temperature 260°C) 15 times to obtain a reliability test sample. After this reliability test, the test substrate was observed, and the adhesion (presence or absence of delamination) between the cured product of the liquid resin composition layer and the part, and between the cured product of the liquid resin composition layer and the wall of the cavity was evaluated according to the following criteria: ◯: No peeling at the interface. ×: Peeling at the interface.

[0356]

[0357] REFERENCE SIGNS LIST 10 Cavity substrate 10U First surface 10D Second surface 11U Non-opening portion 20 Cavity 21 Opening 22 Opening 30 Temporary adhesive material 30U Adhesive surface 40 Component 50 Mask 50U Mask surface 51 Hole 52 Squeegee 521 First squeegee 522 Second squeegee 60 Liquid resin composition 61 Liquid resin composition layer 70 First cured layer 80 Resin sheet 81 Coating resin composition layer 82 Support 90 Second cured layer 100 Intermediate substrate 200 Component-embedded substrate 210 Central portion 220, 230, 240, 250 Corner portion 211 to 214 Cavities 221 to 224 Cavities 231 to 234 Cavities 241 to 244 Cavities 251-254 Cavity

Claims

1. A method for manufacturing a component-embedded substrate, comprising the steps of: (I) preparing a substrate having a cavity that opens to a first surface; (II) attaching a component into the cavity; (III) selectively filling the cavity with a liquid resin composition; (IV) curing the liquid resin composition to form a first cured layer in the cavity; (V) laminating a resin composition layer on the first cured layer; and (VI) curing the resin composition layer to form a second cured layer, in this order; wherein the thickness of the substrate having a cavity that opens to a first surface is 1.0 mm or more, and the mean linear thermal expansion coefficient of the cured liquid resin composition is less than 20 ppm / °C.

2. The method for producing a component-embedded substrate according to claim 1, wherein the cured liquid resin composition has an elastic modulus of 3.5 GPa or more at 25°C.

3. The method for manufacturing a component-embedded substrate according to claim 1, wherein step (V) comprises: preparing a resin sheet having a support and the resin composition layer formed on the support; and laminating the resin sheet and the first cured layer, and laminating the resin composition layer on the first cured layer.

4. The method for manufacturing a component-embedded substrate according to claim 1, wherein the substrate prepared in step (I) has the first surface and a second surface opposite the first surface, the cavity opens to both the first surface and the second surface, and a temporary adhesive material is provided on the second surface.

5. The average linear thermal expansion coefficient of the cured resin composition layer is α Ｓ The average linear thermal expansion coefficient of the cured product of the liquid resin composition is α Ｌ Then, α Ｓ / α Ｌ The method for manufacturing a component-embedded substrate according to claim 1 , wherein the value of the resistivity is greater than 0.6 and not more than 7.

5.

6. The elastic modulus of the cured resin composition layer at 25°C is E Ｓ The elastic modulus of the cured product of the liquid resin composition at 25°C is E Ｌ When this is done, E Ｓ / E Ｌ The method for manufacturing a component-embedded substrate according to claim 1 , wherein the value of the ρ is 0.3 or more and less than 2.

7. The method for producing a component-embedded substrate according to claim 1, wherein the liquid resin composition comprises (A) an inorganic filler, (B) an epoxy resin, and (C) a curing agent.

8. The method for manufacturing a component-embedded substrate according to claim 7, wherein the inorganic filler (A) has an average particle size of 10 μm or less.

9. The method for producing a component-embedded substrate according to claim 1, wherein the viscosity of the liquid resin composition at 25°C is 300 Pa·s or less.

10. The method for producing a component-embedded substrate according to claim 7, wherein the liquid resin composition further contains (D) a dispersant, and component (D) contains any one of an alkylene skeleton, a (meth)acrylic skeleton, and a polyallylamine skeleton.

11. The method for producing a component-embedded substrate according to claim 10, wherein component (D) has a functional group, and the functional group is either a carboxy group or an amino group.

12. The method for producing a component-embedded substrate according to claim 1, wherein the resin composition layer contains (a) an inorganic filler.

13. The method for manufacturing a component-embedded substrate according to claim 12, wherein (a) the inorganic filler has an average particle size of 2 μm or less.

14. A set including a liquid resin composition and a resin sheet having a resin composition layer containing a coating resin composition, wherein the average linear thermal expansion coefficient of a cured product of the coating resin composition is α Ｓ The average linear thermal expansion coefficient of the cured product of the liquid resin composition is α Ｌ Then, α Ｓ / α Ｌ is greater than 0.6 and less than or equal to 7.5.

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