Photosensitive resin composition, photosensitive resin film, multilayer printed wiring board, semiconductor package, and method for manufacturing multilayer printed wiring board

Abstract

To provide a photosensitive resin composition, a photosensitive resin composition for photo via formation and a photosensitive resin composition for an interlayer insulating layer which have high via resolution, have high adhesive strength to plated copper while having low roughness, and are excellent in electric insulation reliability; a photosensitive resin film and a photosensitive resin film for an interlayer insulating layer which are made of the photosensitive resin composition; a multilayer printed wiring board and a semiconductor package; and a method for manufacturing the multilayer printed wiring board.SOLUTION: A photosensitive resin composition contains (A) a photopolymerizable compound having an ethylenically unsaturated group, (B) a photopolymerization initiator, (C) a benzoxazine compound and (D) a thermosetting resin, in which (A) the photopolymerizable compound having the ethylenically unsaturated group contains at least one selected from the group consisting of (A1) a photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group and (A2-1) an acid-modified ethylenically unsaturated group-containing epoxy derivative containing no alicyclic skeleton.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure relates to a photosensitive resin composition, a photosensitive resin film, a multilayer printed wiring board and a semiconductor package, and a method for producing a multilayer printed wiring board. [Background technology]

[0002] In recent years, electronic devices have become smaller and more powerful, and multilayer printed wiring boards are becoming denser due to an increase in the number of circuit layers and finer wiring. In particular, the density of semiconductor package substrates such as BGA (ball grid array) and CSP (chip size package) on which semiconductor chips are mounted is increasing significantly, and in addition to finer wiring, thinner insulating films and smaller vias (also called "via holes") for interlayer connection are required. In addition, as the insulating films in printed wiring boards become thinner, excellent interlayer electrical insulation reliability (especially electrical insulation reliability after moisture absorption (HAST (High Accelerated Stress Test) resistance)) is also required.

[0003] One method for manufacturing a printed wiring board is a build-up method (see, for example, Patent Document 1) in which an interlayer insulating layer and a conductor circuit layer are sequentially laminated to form a multilayer printed wiring board. As circuits become finer, the semi-additive method in which circuits are formed by plating has become mainstream for multilayer printed wiring boards. In conventional semi-additive processes, for example, (1) a thermosetting resin film is laminated onto a conductor circuit, and the thermosetting resin film is hardened by heating to form an "interlayer insulating layer." (2) Next, vias for interlayer connection are formed by laser processing, and desmearing and roughening are performed by alkaline permanganate treatment or the like. (3) After that, electroless copper plating is performed on the board, and after a pattern is formed using a resist, electrolytic copper plating is performed to form a copper circuit layer. (4) Next, the resist is stripped, and the electroless layer is flash etched to form the copper circuit.

[0004] As mentioned above, laser processing is the mainstream method for forming vias in an interlayer insulating layer formed by curing a thermosetting resin film, but the reduction in the diameter of vias by laser irradiation using a laser processing machine has reached its limit. Furthermore, when forming vias using a laser processing machine, each via hole needs to be formed one by one, and when a large number of vias need to be provided due to high density, it takes a long time to form the vias, resulting in poor manufacturing efficiency.

[0005] Under these circumstances, a method has been proposed as a method capable of forming a large number of vias at once, in which a photosensitive resin composition containing (A) an acid-modified vinyl group-containing epoxy resin, (B) a photopolymerizable compound, (C) a photopolymerization initiator, (D) an inorganic filler, and (E) a silane compound is used, in which the content of the inorganic filler (D) is 10 to 80 mass %, and a plurality of small vias are formed at once by a photolithography method (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 7-304931 [Patent Document 2] JP 2017-116652 A Summary of the Invention [Problem to be solved by the invention]

[0007] In Patent Document 2, one of the problems is to suppress the decrease in adhesive strength with plated copper caused by using a photosensitive resin composition instead of a conventional thermosetting resin composition as a material for an interlayer insulating layer or a surface protective layer, and further, the resolution of vias and adhesion to silicon substrates and chip components are also problems, and it is said that these problems have been solved. However, in addition to further miniaturization of wiring, the insulating film is thinned and the via hole for interlayer connection is made smaller in diameter, so there is a growing demand for improvement in adhesive strength with plated copper and electrical insulation reliability. In order to miniaturize wiring, the surface of the insulating film is required to have a low roughness, but if the roughness is low, the adhesive strength with plated copper decreases, so there is a trade-off between miniaturization of wiring and adhesive strength with plated copper. In terms of increasing adhesive strength with plated copper while having a low roughness and electrical insulation reliability, there is room for further improvement in the photosensitive resin composition of Patent Document 2. Similarly, it is conceivable that photosensitive resin compositions, which are conventional materials for solder resist, could be used as materials for the interlayer insulating layer. However, since interlayer insulating layers require properties that were not necessary for solder resist (e.g., reliable electrical insulation between layers, adhesive strength with plated copper, high heat resistance capable of withstanding multiple heating processes, high dimensional accuracy of the via shape, etc.), it is difficult to predict whether such layers will be practical for use as interlayer insulating layers, and they cannot be easily repurposed.

[0008] Therefore, the object of the present invention is to provide a photosensitive resin composition, a photosensitive resin composition for forming photovias, and a photosensitive resin composition for an interlayer insulating layer, which have high via resolution, low roughness, high adhesive strength with plated copper, and excellent electrical insulation reliability. It is also an object of the present invention to provide a photosensitive resin film and a photosensitive resin film for an interlayer insulating layer made of the photosensitive resin composition, to provide a multilayer printed wiring board and a semiconductor package, and to provide a method for producing the multilayer printed wiring board. [Means for solving the problem]

[0009] As a result of extensive research, the present inventors have found that the above object can be achieved by the following invention. That is, the present invention relates to the following [1] to

[19] .

[0010] [1] A photosensitive resin composition comprising: (A) a photopolymerizable compound having an ethylenically unsaturated group; (B) a photopolymerization initiator; (C) a benzoxazine compound; and (D) a thermosetting resin, The photosensitive resin composition, wherein the (A) photopolymerizable compound having an ethylenically unsaturated group comprises at least one selected from the group consisting of (A1) photopolymerizable compounds having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group, and (A2-1) acid-modified ethylenically unsaturated group-containing epoxy derivatives not containing an alicyclic skeleton. [2] The photosensitive resin composition according to the above [1], wherein the (C) benzoxazine compound has 1 to 3 benzoxazine rings in its molecular structure. [3] The photosensitive resin composition according to the above [1] or [2], wherein the (C) benzoxazine compound is a benzoxazine compound represented by any one of the following general formulas (C-1) to (C-3): [ka] (In the formula, R c1 and R c2 are each independently a hydrocarbon group having 1 to 10 carbon atoms. c1 is a single bond, an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 2 to 5 carbon atoms, -O-, a sulfonyl group, a carbonyloxy group, -C(=O)-, or a single bond. c1 and n c2 are each independently an integer of 0 to 4. [ka] (In the formula, R c3 R is each independently a hydrocarbon group having 1 to 10 carbon atoms. c4 are each independently a hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. c2is a single bond, an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 2 to 5 carbon atoms, -O-, a sulfonyl group, a carbonyloxy group, -C(=O)-, or a single bond. c3 are each independently an integer of 0 to 3. [ka] (In the formula, R c5 R is a hydrocarbon group having 1 to 10 carbon atoms. c6 is a hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. c4 is an integer from 0 to 4.) [4] The photosensitive resin composition according to any one of the above [1] to [3], wherein the content of the (C) benzoxazine compound is 0.5 to 30 mass % based on the total solid content of the photosensitive resin composition. [5] The photosensitive resin composition according to any one of the above [1] to [4], wherein in the (A1) photopolymerizable compound having an ethylenically unsaturated group, an acidic substituent, and an alicyclic skeleton, the alicyclic skeleton is an alicyclic skeleton having 5 to 20 ring carbon atoms. [6] The photosensitive resin composition according to any one of the above [1] to [5], wherein in the (A1) photopolymerizable compound having an ethylenically unsaturated group, an acidic substituent, and an alicyclic skeleton, the alicyclic skeleton has two or more rings. [7] The photosensitive resin composition according to any one of the above [1] to [6], wherein the (A) photopolymerizable compound having an ethylenically unsaturated group further comprises at least one member selected from the group consisting of (Ai) a monofunctional vinyl monomer having one polymerizable ethylenically unsaturated group, (Aii) a bifunctional vinyl monomer having two polymerizable ethylenically unsaturated groups, and (Aiii) a polyfunctional vinyl monomer having at least three polymerizable ethylenically unsaturated groups. [8] The photosensitive resin composition according to any one of the above [1] to [7], wherein the (D) thermosetting resin is at least one selected from the group consisting of an epoxy resin, a phenolic resin, an unsaturated imide resin, a cyanate resin, an isocyanate resin, a benzoxazine resin, an oxetane resin, an amino resin, an unsaturated polyester resin, an allyl resin, a dicyclopentadiene resin, a silicone resin, a triazine resin, and a melamine resin. [9] The photosensitive resin composition according to any one of the above [1] to [8], further comprising (E) an elastomer.

[10] The photosensitive resin composition according to [9] above, wherein the (E) elastomer comprises at least one selected from the group consisting of a styrene-based elastomer, an olefin-based elastomer, a polyester-based elastomer, a urethane-based elastomer, a polyamide-based elastomer, an acrylic-based elastomer, and a silicone-based elastomer.

[11] The photosensitive resin composition according to any one of the above [1] to

[10] , further comprising (F) an inorganic filler.

[12] A photosensitive resin composition for forming a photovia, comprising the photosensitive resin composition according to any one of the above [1] to

[11] .

[13] A photosensitive resin composition for an interlayer insulating layer, comprising the photosensitive resin composition according to any one of the above [1] to

[11] .

[14] A photosensitive resin film comprising the photosensitive resin composition according to any one of [1] to

[11] above.

[15] A photosensitive resin film for an interlayer insulating layer, comprising the photosensitive resin composition according to any one of [1] to

[11] above.

[16] A multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin composition according to any one of the above [1] to

[11] .

[17] A multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin film described in

[14] above.

[18] A semiconductor package comprising the multilayer printed wiring board according to

[16] or

[17] above and a semiconductor element mounted thereon.

[19] A method for producing a multilayer printed wiring board, comprising the following steps (1) to (4): Step (1): A step of laminating the photosensitive resin film described in the above item

[14] onto one or both sides of a circuit board. Step (2): A step of forming an interlayer insulating layer having vias by exposing and developing the photosensitive resin film laminated in the step (1). Step (3): A step of roughening the via and the interlayer insulating layer. Step (4): forming a circuit pattern on the interlayer insulating layer. Effect of the Invention

[0011] According to the present invention, it is possible to provide a photosensitive resin composition, a photosensitive resin composition for forming photovias, and a photosensitive resin composition for an interlayer insulating layer, which have high via resolution, high adhesive strength to plated copper while having low roughness, and excellent electrical insulation reliability. It is also possible to provide a photosensitive resin film and a photosensitive resin film for an interlayer insulating layer made of the photosensitive resin composition, and to provide a multilayer printed wiring board and a semiconductor package containing an interlayer insulating layer formed using the photosensitive resin composition or the photosensitive resin film. Furthermore, it is possible to provide a method for efficiently manufacturing a multilayer printed wiring board having high-resolution vias, high adhesive strength between an interlayer insulating layer and plated copper, and excellent electrical insulation reliability. The vias in the multilayer printed wiring board obtained by the manufacturing method of the present invention can be smaller in diameter than vias formed by laser processing. [Brief description of the drawings]

[0012] [Figure 1] 2A to 2C are schematic diagrams illustrating one aspect of a manufacturing process for a multilayer printed wiring board according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] In the numerical ranges described in this specification, the upper or lower limit of the numerical range may be replaced with the values ​​shown in the examples. In addition, the lower and upper limits of the numerical ranges may be arbitrarily combined with the lower or upper limit of other numerical ranges. Furthermore, in this specification, when multiple substances corresponding to each component are present in the photosensitive resin composition, the content of each component means the total content of the multiple substances present in the photosensitive resin composition, unless otherwise specified. In the present specification, the term "number of ring carbon atoms" refers to the number of carbon atoms necessary to form a ring, and does not include the number of carbon atoms of the substituents of the ring. For example, both the cyclohexane skeleton and the methylcyclohexane skeleton have 6 ring carbon atoms. The expression "(meth)acrylic XX" means either or both of acrylic XX and the corresponding methacrylic XX. In addition, the expression "(meth)acryloyl group" means either or both of an acryloyl group and a methacryloyl group. Additionally, any combination of the descriptions in this specification is also included in the present invention.

[0014] [Photosensitive resin composition, photosensitive resin composition for forming photovias, and photosensitive resin composition for interlayer insulating layer] A photosensitive resin composition according to one embodiment of the present invention (hereinafter, may be simply referred to as this embodiment) is a photosensitive resin composition containing (A) a photopolymerizable compound having an ethylenically unsaturated group, (B) a photopolymerization initiator, (C) a benzoxazine compound, and (D) a thermosetting resin, wherein the (A) photopolymerizable compound having an ethylenically unsaturated group includes at least one selected from the group consisting of (A1) photopolymerizable compounds having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group, and (A2-1) acid-modified ethylenically unsaturated group-containing epoxy derivatives that do not contain an alicyclic skeleton. In this specification, the above components may be referred to as component (A), component (B), component (C), component (D), etc., and other components may be abbreviated in the same manner. In this specification, the "resin component" refers to the above component (A), component (B), component (C), component (D), etc., and also includes other components that may be contained as necessary (e.g., component (E), etc.), but does not include inorganic compounds such as inorganic fillers (F) and pigments (G) that may be contained as necessary, which will be described later. In addition, the "solid content" refers to the non-volatile content excluding volatile substances such as water and solvents contained in the photosensitive resin composition, and refers to the components that remain without volatilization when the resin composition is dried, and also includes liquid, starch syrup, and wax-like substances at room temperature around 25°C.

[0015] The photosensitive resin composition of this embodiment is suitable for via formation by photolithography (also referred to as photovia formation), and therefore the present invention also provides a photosensitive resin composition for photovia formation. The photosensitive resin composition of this embodiment also provides a photosensitive resin composition for interlayer insulation layer, and therefore the photosensitive resin composition of this embodiment has high via resolution, low roughness yet high adhesive strength with plated copper, and excellent electrical insulation reliability, and is useful as an interlayer insulation layer of a multilayer printed wiring board. In this specification, the term "photosensitive resin composition" includes photosensitive resin compositions for photovia formation and photosensitive resin compositions for interlayer insulation layer. The photosensitive resin composition of the present embodiment is useful as a negative photosensitive resin composition. Each component that the photosensitive resin composition may contain will be described in detail below.

[0016] <(A) Photopolymerizable compound having an ethylenically unsaturated group> From the viewpoint of adhesive strength with plated copper, the photosensitive resin composition of the present embodiment contains a photopolymerizable compound having an ethylenically unsaturated group as component (A). Examples of the ethylenically unsaturated group contained in component (A) include a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadiimide group, and a (meth)acryloyl group. As the ethylenically unsaturated group, a (meth)acryloyl group is preferable. In the present invention, the component (A) contains at least one selected from the group consisting of "(A1) a photopolymerizable compound having an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group" and "(A2-1) an acid-modified ethylenically unsaturated group-containing epoxy derivative not containing an alicyclic skeleton" described below. In this way, by containing at least one of the components (A1) and (A2-1) in the component (A), a photosensitive resin composition excellent in via resolution, adhesive strength to plated copper, and electrical insulation reliability is obtained. The components will be described in detail below, beginning with component (A1).

[0017] ((A1) Photopolymerizable compound having an ethylenically unsaturated group as well as an acidic substituent and an alicyclic skeleton) The ethylenically unsaturated group contained in the component (A1) can be the same as the ethylenically unsaturated group described above, and is preferably at least one selected from the group consisting of a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadimide group, and a (meth)acryloyl group, more preferably a vinyl group, an allyl group, or a (meth)acryloyl group, and even more preferably a (meth)acryloyl group. The acidic substituent in the component (A1) is preferably at least one selected from the group consisting of a carboxyl group, a sulfonic acid group, a phenolic hydroxyl group, and the like, and more preferably a carboxyl group.

[0018] From the viewpoints of via resolution, adhesive strength to plated copper, and electrical insulation reliability, the alicyclic skeleton of component (A1) is preferably an alicyclic skeleton having 5 to 20 ring carbon atoms, more preferably an alicyclic skeleton having 5 to 18 ring carbon atoms, even more preferably an alicyclic skeleton having 6 to 18 ring carbon atoms, particularly preferably an alicyclic skeleton having 8 to 14 ring carbon atoms, and most preferably an alicyclic skeleton having 8 to 12 ring carbon atoms. From the viewpoints of via resolution, adhesive strength with plated copper, and electrical insulation reliability, the alicyclic skeleton preferably comprises two or more rings, more preferably comprises two to four rings, and even more preferably comprises three rings. Examples of alicyclic skeletons with one ring include a cyclohexane skeleton and a cyclohexene skeleton. Examples of alicyclic skeletons with two or more rings include a norbornane skeleton, a decalin skeleton, a bicycloundecane skeleton, and a saturated dicyclopentadiene skeleton. From the viewpoints of via resolution, adhesive strength with plated copper, and electrical insulation reliability, the alicyclic skeleton is preferably a saturated dicyclopentadiene skeleton, and more preferably an alicyclic skeleton represented by the following general formula (a) (saturated dicyclopentadiene skeleton). [ka] (In general formula (a), R A1 represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the alicyclic skeleton. 1 is an integer between 0 and 6. * is a binding site to other structures.)

[0019] In general formula (a), R A1 Examples of the alkyl group having 1 to 12 carbon atoms represented by include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, etc. As the alkyl group, an alkyl group having 1 to 6 carbon atoms is preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group is further preferable. m 1 represents an integer of 0 to 6, preferably an integer of 0 to 2, and more preferably 0. m 1 When is an integer between 2 and 6, multiple R A1 may be the same or different. A1 may be substituted on the same carbon atom or on different carbon atoms, to the extent possible. * is a bonding site to another structure, and may be bonded to any carbon atom on the alicyclic skeleton. However, it is preferably bonded to a carbon atom represented by 1 or 2 and a carbon atom represented by any of 3 to 5 in the following general formula (a'). [ka] (In general formula (a'), R A1 , m 1 and * are the same as those in general formula (a).

[0020] Examples of the component (A1) include: (A1-1) an acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing epoxy derivative obtained by reacting (a3) ​​a saturated or unsaturated group-containing polybasic acid anhydride with (a2) an ethylenically unsaturated group-containing organic acid compound (hereinafter sometimes referred to as component (A')) obtained by modifying (a1) an alicyclic skeleton-containing epoxy resin with (a2); "(A1-2) Acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing phenol novolac or cresol novolac resin" obtained by reacting (a2) an ethylenically unsaturated group-containing organic acid and (a4) an alicyclic skeleton-containing and saturated or unsaturated group-containing polybasic acid anhydride with a modified novolac epoxy resin obtained by addition polymerization of at least one selected from the group consisting of ethylene oxide and propylene oxide with a phenol novolac resin or cresol novolac resin; etc. As the component (A1), the above-mentioned "(A1-1) acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative" is preferred from the viewpoints of alkali developability, and excellent via resolution, adhesive strength to plated copper, and electrical insulation reliability. First, the raw materials that can be used for producing the "(A1-1) acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing epoxy derivative" will be described in detail.

[0021] -(a1) Alicyclic skeleton-containing epoxy resin- The (a1) alicyclic skeleton-containing epoxy resin is preferably an epoxy resin having two or more epoxy groups. Epoxy resins are classified into glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, etc. Among these, glycidyl ether type epoxy resins are preferred.

[0022] In the present invention, the epoxy resin used is at least an epoxy resin having an alicyclic skeleton. The alicyclic skeleton is explained in the same manner as the alicyclic skeleton of the component (A1) described above, and the preferred embodiments are also the same. The (a1) alicyclic skeleton-containing epoxy resin is preferably an epoxy resin represented by the following general formula (a1-1): Also preferred is an epoxy resin having a structural unit represented by the following general formula (a1-2): [ka] (In general formula (a1-1), R A1 R represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the alicyclic skeleton. A2 represents an alkyl group having 1 to 12 carbon atoms. 1 is an integer between 0 and 6, m 2 is an integer from 0 to 3. n is an integer from 0 to 10. [ka] (In general formula (a1-2), R A1 represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the alicyclic skeleton. 1 is an integer between 0 and 6.)

[0023] In the general formula (a1-1) and the general formula (a1-2), R A1 R in general formula (a) A1 The preferred embodiments are also the same. R in general formula (a1-1) A2Examples of the alkyl group having 1 to 12 carbon atoms represented by include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, etc. As the alkyl group, an alkyl group having 1 to 6 carbon atoms is preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group is further preferable. m in general formula (a1-1) and general formula (a1-2) 1 is m in the general formula (a) 1 The preferred embodiments are also the same. m in general formula (a1-1) 2 represents an integer of 0 to 3, preferably 0 or 1, and more preferably 0. In the general formula (a1-1), n ​​represents the repeating number of the structural unit in the parentheses and is 0 to 10. Usually, an epoxy resin is a mixture of structural units in the parentheses with different repeating numbers, so in that case, n represents the average value of the mixture. n is preferably 2 to 10.

[0024] As the (a1) alicyclic skeleton-containing epoxy resin, a commercially available product may be used. Examples of commercially available products include XD-1000 (trade name, manufactured by Nippon Kayaku Co., Ltd.), EPICLON HP-7200L, EPICLON HP-7200, EPICLON HP-7200HH, and EPICLON HP-7200HHH (trade names, manufactured by DIC Corporation, "EPICLON" is a registered trademark), and the like.

[0025] As the (a1) epoxy resin, epoxy resins other than the epoxy resin having an alicyclic skeleton (hereinafter sometimes referred to as other epoxy resins) may be used in combination. Examples of other epoxy resins include bisphenol-based epoxy resins such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, and bisphenol S type epoxy resins; bisphenol-based novolac type epoxy resins such as bisphenol A novolac type epoxy resins and bisphenol F novolac type epoxy resins; novolac type epoxy resins other than the bisphenol-based novolac type epoxy resins, such as phenol novolac type epoxy resins, cresol novolac type epoxy resins, and biphenyl novolac type epoxy resins; phenol aralkyl type epoxy resins; biphenyl aralkyl type epoxy resins; stilbene type epoxy resins; naphthalene skeleton-containing epoxy resins such as naphthalene type epoxy resins, naphthol novolac type epoxy resins, naphthol type epoxy resins, naphthol aralkyl type epoxy resins, and naphthylene ether type epoxy resins; biphenyl type epoxy resins; xylylene type epoxy resins; dihydroanthracene type epoxy resins; aliphatic linear epoxy resins; and rubber-modified epoxy resins.

[0026] -(a2) Ethylenically unsaturated group-containing organic acid- The (a2) ethylenically unsaturated group-containing organic acid is not particularly limited, but is preferably an ethylenically unsaturated group-containing monocarboxylic acid. The ethylenically unsaturated group is as described above for the ethylenically unsaturated group in the (A1) component. Examples of the ethylenically unsaturated group-containing monocarboxylic acid include acrylic acid; acrylic acid derivatives such as acrylic acid dimers, methacrylic acid, β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, and α-cyanocinnamic acid; half-ester compounds which are reaction products of hydroxyl group-containing acrylates and dibasic acid anhydrides; half-ester compounds which are reaction products of ethylenically unsaturated group-containing monoglycidyl ethers or ethylenically unsaturated group-containing monoglycidyl esters and dibasic acid anhydrides; etc. Among these, acrylic acid is preferred. The component (a2) may be used alone or in combination of two or more kinds.

[0027] The half-ester compound can be obtained, for example, by reacting a hydroxyl group-containing acrylate, an ethylenically unsaturated group-containing monoglycidyl ether or an ethylenically unsaturated group-containing monoglycidyl ester with a dibasic acid anhydride in an equimolar ratio.

[0028] Examples of the hydroxyl group-containing acrylate, ethylenically unsaturated group-containing monoglycidyl ether, and ethylenically unsaturated group-containing monoglycidyl ester used in the synthesis of the half-ester compound, which is an example of the component (a2), include hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, glycidyl acrylate, and glycidyl methacrylate.

[0029] The dibasic acid anhydride used in the synthesis of the half ester compound may contain a saturated group or an unsaturated group. Examples of the dibasic acid anhydride include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, and itaconic anhydride.

[0030] Although not particularly limited, the reaction between the (a1) component and the (a2) component is preferably carried out at a ratio of 0.6 to 1.05 equivalents of the (a2) component per equivalent of the epoxy group of the (a1) component, or may be carried out at a ratio of 0.8 to 1.0 equivalents. By carrying out the reaction at such a ratio, the photopolymerization property is improved, that is, the photosensitivity is increased, and the resolution of the via tends to be improved.

[0031] The component (a1) and the component (a2) can be reacted by dissolving them in an organic solvent. Examples of organic solvents include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, and carbitol acetate; aliphatic hydrocarbons such as octane and decane; and petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

[0032] Furthermore, it is preferable to use a catalyst to promote the reaction between the (a1) component and the (a2) component. Examples of the catalyst include amine catalysts such as triethylamine and benzylmethylamine; quaternary ammonium salt catalysts such as methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide and benzyltrimethylammonium iodide; and phosphine catalysts such as triphenylphosphine. Among these, phosphine catalysts are preferred, and triphenylphosphine is more preferred. The amount of the catalyst used is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and even more preferably 0.1 to 2 parts by mass, relative to 100 parts by mass of the total of the (a1) component and the (a2) component. The amount used above tends to promote the reaction between the (a1) component and the (a2) component.

[0033] In order to prevent polymerization during the reaction, it is preferable to use a polymerization inhibitor, such as hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol, etc. When a polymerization inhibitor is used, the amount thereof is preferably 0.01 to 1 part by mass, more preferably 0.02 to 0.8 parts by mass, and even more preferably 0.05 to 0.5 parts by mass, relative to 100 parts by mass of the total of the (a1) component and the (a2) component, from the viewpoint of improving the storage stability of the composition.

[0034] The reaction temperature of the component (a1) and the component (a2) is preferably 60 to 150°C, more preferably 70 to 120°C, and further preferably 80 to 110°C, from the viewpoint of productivity.

[0035] In this way, it is presumed that the (A') component obtained by reacting the (a1) component with the (a2) component has a hydroxyl group formed by a ring-opening addition reaction between the epoxy group of the (a1) component and the carboxyl group of the (a2) component.

[0036] -(a3) Polybasic acid anhydride- The (a3) ​​component may contain a saturated group or an unsaturated group. Examples of the (a3) ​​component include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, and itaconic anhydride. Among these, tetrahydrophthalic anhydride is preferred from the viewpoint of via resolution.

[0037] It is presumed that by further reacting the above-obtained component (A') with component (a3) ​​containing a saturated or unsaturated group, the hydroxyl groups of component (A') (including the hydroxyl groups originally present in component (a1)) and the acid anhydride groups of component (a3) ​​are semi-esterified to form an acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing epoxy derivative (A1-1).

[0038] In the reaction between the component (A') and the component (a3), for example, the acid value of the acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing epoxy derivative (A1-1) can be adjusted by reacting 0.1 to 1.0 equivalent of the component (a3) ​​with one equivalent of a hydroxyl group in the component (A'). The acid value of the (A1-1) acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing epoxy derivative is preferably 20 to 150 mgKOH / g, more preferably 30 to 120 mgKOH / g, and even more preferably 40 to 100 mgKOH / g. If the acid value is 20 mgKOH / g or more, the photosensitive resin composition tends to have excellent solubility in a dilute alkaline solution, and if it is 150 mgKOH / g or less, the electrical properties of the cured film tend to be improved.

[0039] The reaction temperature between the component (A') and the component (a3) ​​is preferably 50 to 150°C, more preferably 60 to 120°C, and even more preferably 70 to 100°C, from the viewpoint of productivity.

[0040] In view of the above, the (A1) photopolymerizable compound having an ethylenically unsaturated group as well as an acidic substituent and an alicyclic skeleton is not particularly limited, but is preferably represented by the following general formula (A-1). [ka] (In general formula (A-1), R A1 R represents an alkyl group having 1 to 12 carbon atoms, and may be substituted anywhere in the alicyclic skeleton. A2 R represents an alkyl group having 1 to 12 carbon atoms. A3is an organic group having an ethylenically unsaturated group, an organic group having an ethylenically unsaturated group and an acidic substituent, or a glycidyl group, and at least one R A3 is an organic group having an ethylenically unsaturated group and an acidic substituent. 1 is an integer between 0 and 6, m 2 is an integer from 0 to 3. n is an integer from 0 to 10.

[0041] R in the general formula (A-1) A1 , R A2 , m 1 , m 2 and n are the same as those in the general formula (a1-1), and the preferred values ​​are also the same. R A3 is as defined above, but the glycidyl group in the general formula (a1-1) corresponds to a site formed by reacting with the (a2) component and the (a3) ​​component, and the definition takes into consideration that a part of the glycidyl group remains unreacted. A3 The "organic group having an ethylenically unsaturated group" which is an option of R is a group derived from the component (a2), and the "organic group having an ethylenically unsaturated group and an acidic substituent" is a group derived from the components (a2) and (a3). If the components (a2) and (a3) ​​react with all the glycidyl groups in the general formula (a1-1), R A3 is an "organic group having an ethylenically unsaturated group and an acidic substituent", whereas the site that has reacted only with the component (a2) is an "organic group having an ethylenically unsaturated group", and the site that has not reacted with either the component (a2) or the component (a3) ​​is a "glycidyl group".

[0042] Next, raw materials that can be used in the production of the "(A1-2) acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing phenol novolak or cresol novolak resin" will be briefly described. One of the raw materials is a modified novolac type epoxy resin obtained by addition polymerization of at least one selected from the group consisting of ethylene oxide and propylene oxide to a phenol novolac resin or a cresol novolac resin. It is preferable to use a catalyst for the addition polymerization, and examples of the catalyst include metallic sodium, sodium methoxide, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium phenolate, various Lewis acids, etc. The weight average molecular weight of the phenol novolac resin and the cresol novolac resin is not particularly limited, but is preferably 500 to 30,000, and more preferably 1,000 to 10,000. In this specification, the weight average molecular weight is a value calculated in terms of standard polystyrene by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent. The reaction temperature is not particularly limited, but the reaction can be carried out within the range of 60 to 230°C. The addition polymerization may be carried out by utilizing or adapting a known method, and is not limited to the above-mentioned method. By the above addition polymerization, a modified novolac type epoxy resin is obtained.

[0043] The "(a2) ethylenically unsaturated group-containing organic acid" to be reacted with the modified novolac epoxy resin obtained above can be explained in the same manner as in the above-mentioned (a2) ethylenically unsaturated group-containing organic acid. The alicyclic skeleton contained in the "(a4) alicyclic skeleton-containing and saturated or unsaturated group-containing polybasic acid anhydride" to be reacted with the modified novolac epoxy resin obtained above is preferably an alicyclic skeleton having 5 to 20 ring carbon atoms, more preferably an alicyclic skeleton having 5 to 15 ring carbon atoms, even more preferably an alicyclic skeleton having 5 to 10 ring carbon atoms, and particularly preferably an alicyclic skeleton having 5 to 8 ring carbon atoms. The alicyclic skeleton may be one ring or may be one consisting of two or more rings, but is preferably one ring. The alicyclic skeleton is preferably a cyclohexane skeleton, a cyclohexene skeleton, or the like, and more preferably a cyclohexene skeleton. Examples of the "(a4) alicyclic skeleton-containing and saturated or unsaturated group-containing polybasic acid anhydride" include tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, etc. Among these, tetrahydrophthalic anhydride and phthalic anhydride are preferred, and tetrahydrophthalic anhydride is more preferred. There are no particular limitations on the conditions for reacting the modified novolac epoxy resin with the (a2) ethylenically unsaturated group-containing organic acid and the (a4) alicyclic skeleton-containing and saturated or unsaturated group-containing polybasic acid anhydride. For example, a method may be used in which the (a2) component is reacted at 20 to 100° C., if necessary in the presence of a catalyst, and then the (a4) component is reacted at 20 to 100° C.

[0044] ((A1) Molecular Weight of Photopolymerizable Compound Having an Ethylenically Unsaturated Group, an Acidic Substituent, and an Alicyclic Skeleton) The weight average molecular weight (Mw) of the component (A1) is preferably 1,000 to 30,000, more preferably 2,000 to 25,000, and even more preferably 3,000 to 18,000. Within this range, the adhesive strength with plated copper, heat resistance, and electrical insulation reliability are improved. In particular, the weight average molecular weight (Mw) of the acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing epoxy derivative (A1-1) is preferably within the above range. Here, in this specification, the weight average molecular weight is a value measured by gel permeation chromatography (GPC) (manufactured by Tosoh Corporation) using a calibration curve of standard polystyrene, and more specifically, a value measured according to the method described below. <Method for measuring weight average molecular weight> The weight average molecular weight was measured using the following GPC measuring device and measuring conditions, and the value converted using the calibration curve of standard polystyrene was used as the weight average molecular weight. The calibration curve was created using a 5-sample set ("PStQuick MP-H" and "PStQuick B", manufactured by Tosoh Corporation) as standard polystyrene. (GPC measurement device) GPC equipment: High-speed GPC equipment "HCL-8320GPC", detector is differential refractometer or UV, manufactured by Tosoh Corporation Column: TSKgel SuperMultipore HZ-H (column length: 15 cm, column inner diameter: 4.6 mm), manufactured by Tosoh Corporation (Measurement conditions) Solvent: Tetrahydrofuran (THF) Measurement temperature: 40℃ Flow rate: 0.35mL / min Sample concentration: 10mg / THF5mL Injection volume: 20μL

[0045] ((A2-1) Acid-modified ethylenically unsaturated group-containing epoxy derivatives not containing an alicyclic skeleton) As described above, the (A) photopolymerizable compound having an ethylenically unsaturated group may be in an embodiment including "(A2-1) an acid-modified ethylenically unsaturated group-containing epoxy derivative not containing an alicyclic skeleton". The (A2-1) component is preferably obtained by reacting (a23) a saturated or unsaturated group-containing polybasic acid anhydride with (a21) an epoxy resin (not containing an alicyclic skeleton) modified with (a22) an ethylenically unsaturated group-containing organic acid.

[0046] The epoxy resin (a21) is not particularly limited as long as it is an epoxy resin that does not contain an alicyclic skeleton, and examples thereof include glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, etc. Among these, glycidyl ether type epoxy resins are preferred. In addition, the (a21) epoxy resins are classified into various epoxy resins depending on the difference in the main skeleton, and each of the above types of epoxy resins is further classified as follows. Specifically, they are classified into bisphenol-based epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, and bisphenol S type epoxy resin; bisphenol-based novolac type epoxy resins such as bisphenol A novolac type epoxy resin and bisphenol F novolac type epoxy resin; novolac type epoxy resins other than the above-mentioned bisphenol-based novolac type epoxy resins, such as phenol novolac type epoxy resin, cresol novolac type epoxy resin, and biphenyl novolac type epoxy resin; phenol aralkyl type epoxy resins; stilbene type epoxy resins; naphthalene skeleton-containing epoxy resins such as naphthalene type epoxy resin, naphthol novolac type epoxy resin, naphthol type epoxy resin, naphthol aralkyl type epoxy resin, and naphthylene ether type epoxy resin; biphenyl type epoxy resin; biphenyl aralkyl type epoxy resin; xylylene type epoxy resin; dihydroanthracene type epoxy resin; aliphatic linear epoxy resin; and rubber-modified epoxy resins. Among these, bisphenol-based novolac type epoxy resins are preferred, and bisphenol F novolac type epoxy resins are more preferred.

[0047] The (a22) ethylenically unsaturated group-containing organic acid and the (a23) saturated or unsaturated group-containing polybasic acid anhydride can be explained in the same manner as the (a2) ethylenically unsaturated group-containing organic acid and the (a3) ​​saturated or unsaturated group-containing polybasic acid anhydride, and preferred embodiments are also the same. As a method for reacting the compound obtained by modifying the (a21) component with the (a22) component with the (a23) component, reference can be made to a method for reacting the compound obtained by modifying the (a1) component with the (a2) component with the (a3) ​​component.

[0048] As the (A2-1) acid-modified ethylenically unsaturated group-containing epoxy derivative not containing an alicyclic skeleton, commercially available products may be used. Examples of commercially available products include CCR-1218H, CCR-1159H, CCR-1222H, PCR-1050, TCR-1335H, ZAR-1035, ZAR-2001H, UXE-3024, ZFR-1185, ZCR-1569H, ZXR-1807, ZCR-6000, ZCR-8000 (all of which are product names manufactured by Nippon Kayaku Co., Ltd.), UE-9000, UE-EXP-2810PM, and UE-EXP-3045 (all of which are product names manufactured by DIC Corporation).

[0049] When the component (A) contains both the component (A1) (or the component (A1-1)) and the component (A2-1), from the viewpoint of a balance of properties such as via resolution, adhesive strength with plated copper, and electrical insulation reliability, the content ratio of the component (A1) (or the component (A1-1)) to the component (A2-1) [(A1) or (A1-1) / (A2-1)], expressed by mass ratio, is preferably 20 / 80 to 99 / 1, more preferably 50 / 50 to 99 / 1, even more preferably 60 / 40 to 99 / 1, particularly preferably 60 / 40 to 85 / 15, and most preferably 65 / 35 to 80 / 20.

[0050] ((A2-2) Styrene-maleic acid resin) As the (A) photopolymerizable compound having an ethylenically unsaturated group, "(A2-2) styrene-maleic acid resin" such as a hydroxyethyl (meth)acrylate modified product of a styrene-maleic anhydride copolymer can be used in combination. The (A2-2) component does not contain an alicyclic skeleton. The (A2-2) component may be used alone or in combination of two or more.

[0051] ((A2-3) Epoxy-based polyurethane resin) In addition, as the (A) photopolymerizable compound having an ethylenically unsaturated group, an "(A2-3) epoxy polyurethane resin" obtained by reacting a compound obtained by modifying the (a21) epoxy resin with an (a22) ethylenically unsaturated group-containing organic acid (for example, (A') component) with an isocyanate compound can also be used in combination. The (A2-3) component does not contain an alicyclic skeleton. The (A2-3) component may be used alone or in combination of two or more.

[0052] (Component (A) other than the above) From the viewpoint of increasing the chemical resistance after curing (exposure) and increasing the difference in developer resistance between the exposed and unexposed areas, the photopolymerizable compound (A) having an ethylenically unsaturated group is preferably further comprised of at least one selected from the group consisting of (Ai) a monofunctional vinyl monomer having one polymerizable ethylenically unsaturated group, (Aii) a bifunctional vinyl monomer having two polymerizable ethylenically unsaturated groups, and (Aiii) a multifunctional vinyl monomer having at least three polymerizable ethylenically unsaturated groups, and more preferably comprises the component (Aiii). The components (Ai) to (Aiii) preferably have a molecular weight of 1,000 or less. However, in the present invention, the components (Ai) to (Aiii) do not include the component (A).

[0053] ((Ai) Monofunctional vinyl monomer) Examples of the monofunctional vinyl monomer having one polymerizable ethylenically unsaturated group include (meth)acrylic acid, (meth)acrylic acid alkyl esters, etc. Examples of the (meth)acrylic acid alkyl esters include (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (meth)acrylic acid butyl ester, (meth)acrylic acid 2-ethylhexyl ester, (meth)acrylic acid hydroxyl ethyl ester, etc. The (Ai) component may be used alone or in combination of two or more.

[0054] ((Aii) Bifunctional vinyl monomer) Examples of the bifunctional vinyl monomer having two polymerizable ethylenically unsaturated groups include polyethylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, polypropylene glycol di(meth)acrylate, 2,2-bis(4-(meth)acryloxypolyethoxypolypropoxyphenyl)propane, bisphenol A diglycidyl ether di(meth)acrylate, etc. The component (Aii) may be used alone or in combination of two or more.

[0055] ((Aiii) Multifunctional vinyl monomer) Examples of the polyfunctional vinyl monomer having at least three polymerizable ethylenically unsaturated groups include (meth)acrylate compounds having a skeleton derived from trimethylolpropane, such as trimethylolpropane tri(meth)acrylate; (meth)acrylate compounds having a skeleton derived from tetramethylolmethane, such as tetramethylolmethane tri(meth)acrylate and tetramethylolmethane tetra(meth)acrylate; (meth)acrylate compounds having a skeleton derived from pentaerythritol, such as pentaerythritol tri(meth)acrylate and pentaerythritol tetra(meth)acrylate; (meth)acrylate compounds having a skeleton derived from dipentaerythritol, such as dipentaerythritol penta(meth)acrylate and dipentaerythritol hexa(meth)acrylate; (meth)acrylate compounds having a skeleton derived from ditrimethylolpropane, such as ditrimethylolpropane tetra(meth)acrylate; and (meth)acrylate compounds having a skeleton derived from diglycerin. Among these, from the viewpoint of increasing the chemical resistance after curing (exposure) and increasing the difference in developer resistance between the exposed and unexposed areas, a (meth)acrylate compound having a skeleton derived from dipentaerythritol is preferred, and dipentaerythritol penta(meth)acrylate is more preferred. The component (Aiii) may be used alone or in combination of two or more. Here, the "(meth)acrylate compound having a skeleton derived from XXX" (wherein XXX is the name of the compound) means an esterification product of XXX and (meth)acrylic acid, and the esterification product also includes a compound modified with an alkyleneoxy group.

[0056] (Content of component (A)) The content of the component (A) is not particularly limited, but from the viewpoints of heat resistance, electrical properties, and chemical resistance, it is preferably 5 to 60 mass %, more preferably 10 to 55 mass %, even more preferably 20 to 50 mass %, particularly preferably 25 to 50 mass %, and most preferably 30 to 45 mass %, based on the total solid content of the photosensitive resin composition.

[0057] Although there is no particular limitation on the component (A), it is preferable to use the component (A1) or the component (A2-1) in combination with the component (Aiii) from the viewpoint of photosensitive properties. In this case, the content ratio of the component (A1) or the component (A2-1) to the component (Aiii) [{(A1) or (A2-1)} / (Aiii)] (mass ratio) is preferably 2 to 20, more preferably 2 to 15, even more preferably 2.5 to 10, and particularly preferably 3 to 6. Furthermore, the content ratio of the component (A1) relative to the total amount of the component (A) is preferably 20 to 95 mass%, more preferably 40 to 90 mass%, even more preferably 55 to 90 mass%, and particularly preferably 70 to 90 mass%, from the viewpoints of via resolution, adhesive strength with plated copper, electrical insulation reliability, and crack resistance.

[0058] <(B) Photopolymerization initiator> The component (B) used in the present embodiment is not particularly limited as long as it can polymerize the component (A), and can be appropriately selected from commonly used photopolymerization initiators. Examples of the component (B) include benzoins such as benzoin, benzoin methyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-methyl-1-[4-(methyl acetophenones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone; anthraquinones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone, Thioxanthones such as xanthones; ketals such as acetophenone dimethyl ketal and benzil dimethyl ketal; benzophenones such as benzophenone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4,4'-bis(diethylamino)benzophenone, Michler's ketone, and 4-benzoyl-4'-methyldiphenyl sulfide; acridines such as 9-phenylacridine and 1,7-bis(9,9'-acridinyl)heptane; 2,4,6- Examples of the acylphosphine oxides include trimethylbenzoyldiphenylphosphine oxide; oxime esters such as 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-(O-benzoyloxime), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone-1-(O-acetyloxime), and 1-phenyl-1,2-propanedione-2-[O-(ethoxycarbonyl)oxime]. Among these, acetophenones and thioxanthones are preferred, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone and 2,4-diethylthioxanthones are more preferred. Acetophenones have the advantage of being less volatile and less likely to be generated as outgassing, and thioxanthones have the advantage of being photocurable even in the visible light range. The component (B) may be used alone or in combination of two or more. When using two or more in combination, it is preferable to use acetophenones and thioxanthones in combination, and it is more preferable to use 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone in combination with 2,4-diethylthioxanthone.

[0059] (B) Component Content In the photosensitive resin composition of the present embodiment, the content of the (B) component is not particularly limited, but is preferably 0.1 to 15 mass%, more preferably 0.15 to 5 mass%, further preferably 0.15 to 1.5 mass%, and particularly preferably 0.20 to 0.8 mass%, based on the total solid content of the photosensitive resin composition. If the content of the (B) component is 0.1 mass% or more, the risk of the exposed portion of the interlayer insulating layer formed using the photosensitive resin composition being eluted during development tends to be reduced, and if it is 15 mass% or less, the heat resistance tends to be improved.

[0060] <(B') Photopolymerization initiator aid> The photosensitive resin composition of the present embodiment may contain a photopolymerization initiation aid (B') together with the above-mentioned component (B). Examples of the photopolymerization initiation aid (B') include tertiary amines such as N,N-dimethylaminobenzoic acid ethyl ester, N,N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, and triethanolamine. The component (B') may be used alone or in combination of two or more. When the photosensitive resin composition of the present embodiment contains the component (B'), the content thereof is preferably 0.01 to 20 mass%, more preferably 0.2 to 5 mass%, and further preferably 0.3 to 2 mass%, based on the total amount of the resin components of the photosensitive resin composition. The photosensitive resin composition of the present embodiment does not necessarily need to contain the component (B').

[0061] <(C) Benzoxazine Compound> The photosensitive resin composition of the present embodiment contains a benzoxazine compound (C). The component (C) may be used alone or in combination of two or more kinds. By including the component (C), the effect of improving adhesion to plated copper is exhibited. Phenol resins and the like can be used to improve adhesion to plated copper, but in that case, the sensitivity of the photosensitive resin composition decreases, and productivity decreases. However, the component (C) used in the present invention does not cause such problems, improves adhesion to plated copper, and furthermore, has a high glass transition temperature and tends to maintain good dielectric properties. Although the exact mechanism by which component (C) provides the above effects is unknown, it is speculated as follows: Because component (C) has a benzoxazine ring in its molecular structure, it undergoes a ring-opening polymerization reaction when heated, generating phenolic hydroxyl groups without generating volatile matter and forming a crosslinked structure, which is thought to result in the above effects.

[0062] The component (C) is not particularly limited as long as it is a compound having one or more benzoxazine rings in its molecular structure, but it preferably has one to three benzoxazine rings in its molecular structure, and more preferably has two benzoxazine rings in its molecular structure. As the component (C), a known benzoxazine compound can be used, for example, a Pd-type benzoxazine compound, a Fa-type benzoxazine compound, an ALP-d-type benzoxazine compound, a T-ala-type benzoxazine compound, etc. are listed. It is considered that Pd-type polybenzoxazine is crosslinked by a rigid structure and has a small free volume, and therefore has excellent thermal and mechanical properties. On the other hand, in polybenzoxazine having a Fa-type benzoxazine structure, the aryl group is a steric hindrance, and it is considered that the thermal and mechanical properties are inferior to those of Pd-type polybenzoxazine, but the steric structure gives it excellent solubility in solvents, and it can be suitably used as a film material.

[0063] Examples of the component (C) include a benzoxazine compound represented by the following general formula (C-1), a benzoxazine compound represented by the following general formula (C-2), and a benzoxazine compound represented by the following general formula (C-3). The benzoxazine compound represented by the following general formula (C-1) corresponds to a Pd-type benzoxazine compound, and the benzoxazine compound represented by the following general formula (C-2) corresponds to a Fa-type benzoxazine compound. [ka] (In the formula, R c1 and R c2 are each independently a hydrocarbon group having 1 to 10 carbon atoms. c1 is a single bond, an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 2 to 5 carbon atoms, -O-, a sulfonyl group, a carbonyloxy group, -C(=O)-, or a single bond. c1 and n c2 are each independently an integer of 0 to 4. [ka] (In the formula, R c3 R is each independently a hydrocarbon group having 1 to 10 carbon atoms. c4 are each independently a hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. c2 is a single bond, an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 2 to 5 carbon atoms, -O-, a sulfonyl group, a carbonyloxy group, -C(=O)-, or a single bond. c3 are each independently an integer of 0 to 3. [ka] (In the formula, R c5 R is a hydrocarbon group having 1 to 10 carbon atoms. c6 is a hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. c4 is an integer between 0 and 4.)

[0064] In the above general formula (C-1), Rc1 and R c2 Examples of the hydrocarbon group having 1 to 10 carbon atoms represented by include aliphatic hydrocarbon groups such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, an n-octyl group, and an n-decyl group; and aromatic hydrocarbon groups such as a phenyl group. In the above general formula (C-1), n c1 and n c2 are each independently an integer of 0 to 4, and from the viewpoint of availability, an integer of 0 to 2 is preferable, and 0 is more preferable. c1 and n c2 If is an integer equal to or greater than 2, multiple R c1 R c2 They may be the same or different. In the above general formula (C-1), X c1 Examples of the alkylene group having 1 to 5 carbon atoms represented by include a methylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group, a 1,5-pentamethylene group, etc. As the alkylene group, an alkylene group having 1 to 3 carbon atoms is preferable, and a methylene group is more preferable. In the above general formula (C-1), X c1 Examples of the alkylidene group having 2 to 5 carbon atoms represented by include an ethylidene group, a propylidene group, an isopropylidene group, a butylidene group, an isobutylidene group, a pentylidene group, an isopentylidene group, etc. Among these, an isopropylidene group is preferable.

[0065] In the above general formula (C-2), R c3 Examples of the hydrocarbon group having 1 to 10 carbon atoms represented by include aliphatic hydrocarbon groups such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, an n-octyl group, and an n-decyl group; and aromatic hydrocarbon groups such as a phenyl group. In the above general formula (C-2), n c3 is an integer of 0 to 3, and from the viewpoint of availability, an integer of 0 to 2 is preferable, and 0 is more preferable. In the above general formula (C-2), Xc2 The alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by X in the above general formula (C-1) are c1 Examples of the alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by the formula (I) are the same as those represented by the formula (I). In the above general formula (C-2), R c4 Examples of the hydrocarbon group having 1 to 10 carbon atoms represented by include alkyl groups such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, and n-pentyl group; and aromatic hydrocarbon groups such as phenyl group and naphthyl group. Among these, aromatic hydrocarbon groups are preferred, and phenyl group is more preferred.

[0066] In the above general formula (C-3), R c5 Examples of the hydrocarbon group having 1 to 10 carbon atoms represented by include aliphatic hydrocarbon groups such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, an n-octyl group, and an n-decyl group; and aromatic hydrocarbon groups such as a phenyl group. In the above general formula (C-3), n c4 is an integer of 0 to 4, and from the viewpoint of availability, is preferably an integer of 0 to 2, and more preferably 0. c4 If is an integer equal to or greater than 2, multiple R c5 They may be the same or different. In the above general formula (C-3), R c6 The hydrocarbon group having 1 to 10 carbon atoms represented by R in the above general formula (C-2) is c4 Examples of the hydrocarbon group include the same hydrocarbon groups having 1 to 10 carbon atoms as those represented by the formula:

[0067] Among the benzoxazine compounds represented by any of the above general formulas (C-1) to (C-3), from the viewpoint of heat resistance, the benzoxazine compound represented by the above general formula (C-1) and the benzoxazine compound represented by the above general formula (C-2) are preferred, and the benzoxazine compound represented by the above general formula (C-1) is more preferred. From the viewpoint of adhesion to copper plating, the benzoxazine compound represented by the above general formula (C-1) is preferably a benzoxazine compound represented by the following formula (C-4), and the benzoxazine compound represented by the above general formula (C-2) is preferably a benzoxazine compound represented by the following formula (C-5).

[0068] [ka]

[0069] [ka]

[0070] (C) Method for producing benzoxazine compounds The method for producing the component (C) is not particularly limited, and a known method can be used. For example, the benzoxazine compound (C) can be produced by the reaction of (c1) a compound having a phenolic hydroxyl group with a hydrogen atom bonded to at least one of the ortho positions [hereinafter, sometimes abbreviated as compound (c1) having a phenolic hydroxyl group], (c2) a primary amine [hereinafter, referred to as primary amine (c2)], and (c3) formaldehyde [hereinafter, referred to as formaldehyde (c3)]. For example, when the compound (c1) having a phenolic hydroxyl group is phenol and the primary amine (c2) is aniline, the above reaction is represented by the following reaction formula (1). [ka]

[0071] Examples of the compound (c1) having a phenolic hydroxyl group, which is one of the raw materials, include phenols, polyfunctional phenols, biphenol compounds, bisphenols, trisphenols, tetraphenols, and phenol resins. Among these, phenols are preferred, and phenol is more preferred. Examples of the phenols include phenol, 2-methylphenol, 4-methylphenol, 2-ethylphenol, and 3-methyl-4-isopropylphenol. The compound (c1) having a phenolic hydroxyl group may be used alone or in combination of two or more kinds, but it is usually preferred to use one kind alone.

[0072] Examples of the primary amine (c2), which is one of the raw materials, include aliphatic amines such as methylamine, butylamine, and cyclohexylamine; and aromatic amines such as aniline, substituted aniline, toluidine, and anisidine. Among these, aromatic amines are preferred, aniline and substituted aniline are more preferred, and aniline is even more preferred. Examples of the substituted aniline include 2-methoxyaniline and 4-methoxyaniline. The primary amine (c2) may be used alone or in combination of two or more kinds, but it is usually preferred to use one kind alone.

[0073] As formaldehyde (c3), which is one of the raw materials, formalin (aqueous formaldehyde solution) can be used, and also paraformaldehyde, which is a solid, can be used.

[0074] In producing the component (C), there is no particular restriction on the amount of each of the raw materials used, but it is preferable to use 0.5 to 1 mole of the primary amine (c2) per mole of the phenolic hydroxyl group of the compound (c1) having a phenolic hydroxyl group, and 2 moles or more of formaldehyde (c3) per mole of the primary amine (c2). By using the primary amine (c2) in the amount described above, a part of the phenolic hydroxyl group of the compound (c1) having a phenolic hydroxyl group tends to remain unreacted, and the adhesiveness and glass transition temperature tend to be improved.

[0075] The production conditions of the component (C) may be any known conditions. Specifically, a mixture of the compound (c1) having a phenolic hydroxyl group and the primary amine (c2) is added to formaldehyde (c3) heated to preferably 70°C or higher (more preferably 70 to 110°C), reacted at preferably 70 to 110°C (more preferably 90 to 100°C) for preferably 20 minutes to 8 hours (more preferably 20 minutes to 2 hours), and then dried under reduced pressure at 120°C or lower to obtain the component (C).

[0076] After the reaction is completed, the product is separated by a method commonly used in organic synthetic chemistry, such as extraction, and volatile components such as condensation water are removed by drying, thereby obtaining the benzoxazine compound (C). By utilizing or applying the above-mentioned production methods, benzoxazine compounds (C) having various structures can be obtained. As the benzoxazine compound (C), commercially available products can also be used, such as "Pd-type benzoxazine" and "Fa-type benzoxazine" manufactured by Shikoku Chemical Industry Co., Ltd., benzoxazine resin manufactured by Konishi Chemical Industry Co., Ltd., and cashew benzoxazine resin manufactured by Tohoku Kako Co., Ltd.

[0077] ((C) Component Content) In the photosensitive resin composition of the present embodiment, the content of the component (C) is not particularly limited, but is preferably 0.5 to 30 mass%, more preferably 0.8 to 25 mass%, further preferably 1 to 20 mass%, particularly preferably 1 to 18 mass%, and most preferably 1 to 5 mass%, based on the total solid content of the photosensitive resin composition. If the content of the component (C) is 0.5 mass% or more, the adhesive strength with plated copper and the electrical insulation reliability are improved with low roughness. On the other hand, if it is 30 mass% or less, the resolution is good.

[0078] <(D) Thermosetting resin> The photosensitive resin composition of the present embodiment may further contain, and preferably contains, a thermosetting resin as component (D). Component (D) does not include anything that corresponds to component (A), and in that respect, component (D) can be said to have no ethylenically unsaturated groups. By including the thermosetting resin (D) in the photosensitive resin composition of the present embodiment, the adhesive strength with plated copper and the insulation reliability are improved, and the heat resistance tends to be improved. This is presumably because, in addition to the formation of a crosslinked structure by the thermosetting resin (D), a crosslinked structure is formed between the phenolic hydroxyl group generated by heating the benzoxazine compound (C) and the thermosetting resin (D).

[0079] Examples of the thermosetting resin include epoxy resin, phenol resin, unsaturated imide resin, cyanate resin, isocyanate resin, benzoxazine resin, oxetane resin, amino resin, unsaturated polyester resin, allyl resin, dicyclopentadiene resin, silicone resin, triazine resin, melamine resin, etc. Also, the thermosetting resin is not particularly limited to these, and any known thermosetting resin can be used. Among these, epoxy resin is preferable. The component (D) may be used alone or in combination of two or more types.

[0080] The epoxy resin is preferably an epoxy resin having two or more epoxy groups. Epoxy resins are classified into glycidyl ether type epoxy resins, glycidyl amine type epoxy resins, glycidyl ester type epoxy resins, etc. Among these, glycidyl ether type epoxy resins are preferred.

[0081] Epoxy resins are also classified into various epoxy resins according to the difference in the main skeleton, and each of the above types of epoxy resins is further classified as follows: Specifically, bisphenol-based epoxy resins such as bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, and bisphenol S-type epoxy resins; bisphenol-based novolac-type epoxy resins such as bisphenol A-type novolac-type epoxy resins and bisphenol F-type novolac-type epoxy resins; novolac-type epoxy resins other than the above bisphenol-based novolac-type epoxy resins, such as phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, and biphenyl novolac-type epoxy resins; phenol aralkyl-type epoxy resins; stilbene-type epoxy resins; and naphthalene-type epoxy resins. Epoxy resins are classified into naphthalene skeleton-containing epoxy resins such as naphthol novolac type epoxy resins, naphthol type epoxy resins, naphthol aralkyl type epoxy resins, and naphthylene ether type epoxy resins; biphenyl type epoxy resins; biphenyl aralkyl type epoxy resins; xylylene type epoxy resins; dihydroanthracene type epoxy resins; alicyclic epoxy resins such as dicyclopentadiene type epoxy resins; heterocyclic epoxy resins; spiro ring-containing epoxy resins; cyclohexane dimethanol type epoxy resins; trimethylol type epoxy resins; aliphatic linear epoxy resins; and rubber-modified epoxy resins. The component (D) may be used alone or in combination of two or more types.

[0082] Among these, particularly from the viewpoints of heat resistance, electrical insulation reliability, and adhesive strength with plated copper, bisphenol-based epoxy resins, naphthol-type epoxy resins, naphthalene-type epoxy resins, biphenyl-type epoxy resins, naphthylene ether-type epoxy resins, and cresol novolac-type epoxy resins are preferred, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, and biphenyl-type epoxy resins are more preferred, bisphenol F-type epoxy resins and biphenyl-type epoxy resins are even more preferred, and biphenyl-type epoxy resins are particularly preferred. These may be commercially available products. For example, bisphenol A type epoxy resins ("jER828EL" and "YL980" manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resins ("jER806H" and "YL983U" manufactured by Mitsubishi Chemical Corporation), naphthalene type epoxy resins ("HP4032D" and "HP4710" manufactured by DIC Corporation), naphthalene skeleton-containing multifunctional epoxy resins ("NC7000" manufactured by Nippon Kayaku Co., Ltd.), naphthol type epoxy resins ("ESN-47" manufactured by Nippon Steel Chemical & Material Co., Ltd.), etc. Examples of epoxy resins that can be used include epoxy resins having a biphenyl structure (manufactured by Nippon Kayaku Co., Ltd., "NC3000H", "NC3500"), manufactured by Mitsubishi Chemical Corporation ("YX4000HK", "YL6121"), anthracene-type epoxy resins (manufactured by Mitsubishi Chemical Corporation, "YX8800"), glycerol-type epoxy resins (manufactured by Nippon Steel Chemical & Material Co., Ltd., "ZX1542"), naphthylene ether-type epoxy resins (manufactured by DIC Corporation, "EXA7311-G4"), and cresol novolac-type epoxy resins (manufactured by DIC Corporation, "EPICLON N-680").

[0083] ((D) Component Content) In the photosensitive resin composition of the present embodiment, the content of the (D) component is not particularly limited, but is preferably 5 to 70 mass%, more preferably 5 to 40 mass%, further preferably 7 to 30 mass%, and particularly preferably 8 to 20 mass%, based on the total solid content of the photosensitive resin composition. If the (D) component content is 5 mass% or more, sufficient crosslinking of the photosensitive resin composition is obtained, and the adhesive strength with plated copper and the electrical insulation reliability tend to be improved. On the other hand, if it is 70 mass% or less, the resolution of the vias tends to be good.

[0084] <(E) Elastomer> The photosensitive resin composition of the present embodiment may contain, and preferably contains, an elastomer as component (E). By containing component (E), the photosensitive resin composition tends to have excellent via resolution, adhesive strength with plated copper, and electrical insulation reliability. In addition, component (E) has the effect of suppressing a decrease in flexibility and adhesive strength with plated copper caused by distortion (internal stress) inside the cured product due to cure shrinkage of component (A). As component (E), an elastomer that is liquid at 25°C is preferred. The component (E) may be used alone or in combination of two or more types.

[0085] Examples of the elastomer include styrene-based elastomers, olefin-based elastomers, polyester-based elastomers, urethane-based elastomers, polyamide-based elastomers, acrylic-based elastomers, silicone-based elastomers, etc., and it is preferable to use at least one selected from these. These elastomers are composed of a hard segment component and a soft segment component, the former of which tends to contribute to heat resistance and strength, and the latter of which tends to contribute to flexibility and toughness. Among the above-listed components, from the viewpoints of compatibility, solubility, and adhesive strength with plated copper, it is preferable that component (E) contains at least one selected from the group consisting of olefin-based elastomers, polyester-based elastomers, and urethane-based elastomers, and it is more preferable that component (E) contains at least one selected from the group consisting of olefin-based elastomers, polyester-based elastomers, and urethane-based elastomers, and it is particularly ... a polyester-based elastomer.

[0086] (Polyester elastomer) The polyester elastomer may be one obtained by polycondensation of a dicarboxylic acid or a derivative thereof and a diol compound or a derivative thereof. The polyester elastomer may be used alone or in combination of two or more kinds. Examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid; aromatic dicarboxylic acids in which hydrogen atoms in the aromatic rings of the aromatic dicarboxylic acids are substituted with methyl groups, ethyl groups, phenyl groups, and the like; aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid, and dodecanedicarboxylic acid; and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. As the dicarboxylic acid, it is also preferable to use a dimer acid derived from a natural product from the viewpoint of adhesion to a substrate. The dicarboxylic acid may be used alone or in combination of two or more kinds. Examples of the derivatives of the dicarboxylic acids include anhydrides of the dicarboxylic acids.

[0087] Examples of the diol compound include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, and 1,10-decanediol; alicyclic diols such as 1,4-cyclohexanediol; and aromatic diols represented by the following general formula (E-1). The diol compounds may be used alone or in combination of two or more.

[0088] [ka] (In general formula (E-1), X E1 represents an alkylene group having 1 to 10 carbon atoms, an alkylidene group having 2 to 10 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, -O-, -S-, or -SO2-. E1 and R E2 each independently represents a halogen atom or an alkyl group having 1 to 12 carbon atoms; p and q each independently represent an integer of 0 to 4, and r is 0 or 1.

[0089] In general formula (E-1), X E1Examples of the alkylene group having 1 to 10 carbon atoms represented by include a methylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group, a 1,5-pentamethylene group, etc. As the alkylene group, from the viewpoints of via resolution, adhesive strength with plated copper, and electrical insulation reliability, an alkylene group having 1 to 3 carbon atoms is preferred, and a methylene group is more preferred. X E1 Examples of the alkylidene group having 2 to 10 carbon atoms represented by include an ethylidene group, a propylidene group, an isopropylidene group, a butylidene group, an isobutylidene group, a pentylidene group, an isopentylidene group, etc. As the alkylidene group, an isopropylidene group is preferred from the viewpoints of via resolution, adhesive strength with plated copper, and electrical insulation reliability. X E1 Examples of the cycloalkylene group having 4 to 8 carbon atoms represented by include a cyclopentylene group, a cyclohexylene group, and a cyclooctylene group. X E1 Of the above, an alkylene group having 1 to 10 carbon atoms and an alkylidene group having 2 to 10 carbon atoms are preferable, and a methylene group and an isopropylidene group are more preferable.

[0090] In general formula (E-1), R E1 and R E2 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. R E1 and R E2 Examples of the alkyl group having 1 to 12 carbon atoms represented by include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, etc. As the alkyl group, an alkyl group having 1 to 6 carbon atoms is preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group is further preferable. p and q each independently represent an integer of 0 to 4, and are each preferably 0 or 1. r may be either 0 or 1, but when r is 0, the structure is represented by the following general formula (D-1′). [ka] (In general formula (E-1'), X E1 , R E1 and p are the same as those in general formula (E-1), and the preferred embodiments are also the same.

[0091] Examples of the aromatic diol represented by the general formula (E-1) include bisphenol A, bis(4-hydroxyphenyl)methane, bis(4-hydroxy-3-methylphenyl)propane, and resorcin.

[0092] Furthermore, as the polyester-based elastomer, a multiblock copolymer in which an aromatic polyester (e.g., polybutylene terephthalate) portion is a hard segment component and an aliphatic polyester (e.g., polytetramethylene glycol) portion is a soft segment component can also be used, and it is preferable to use such a multiblock copolymer. As such multiblock copolymers, there are commercially available products of various grades depending on the type, ratio, and molecular weight of the hard and soft segments, and specific examples include "Hytrel (registered trademark)" (manufactured by DuPont-Toray Co., Ltd.), "Pelprene (registered trademark)" (manufactured by Toyobo Co., Ltd.), "Espel (registered trademark)" and "Teslac (registered trademark)" (manufactured by Hitachi Chemical Co., Ltd.), etc.

[0093] The polyester elastomer preferably has a number average molecular weight of 900 to 30,000, more preferably 1,000 to 25,000, and even more preferably 5,000 to 20,000.

[0094] (Other elastomers) The component (E) may be at least one selected from the group consisting of polyphenylene ether resin, phenoxy resin, polycarbonate resin, polyamideimide resin, polyimide resin, xylene resin, polyphenylene sulfide resin, polyetherimide resin, polyetheretherketone resin, tetrafluoroethylene resin, polyacrylonitrile resin, maleic anhydride-modified polybutadiene, phenol-modified polybutadiene, and carboxy-modified polyacrylonitrile.

[0095] ((E) Component Content) When the photosensitive resin composition of the present embodiment contains the (E) component, the content thereof is preferably 0.5 to 20 mass%, more preferably 0.5 to 15 mass%, further preferably 0.5 to 10 mass%, particularly preferably 1.0 to 6 mass%, and most preferably 1.3 to 4.0 mass% based on the total solid content of the photosensitive resin composition. If the (E) component content is 0.5 mass% or more, the effect of improving the adhesive strength with plated copper becomes sufficient, and the electrical insulation reliability tends to be even more excellent. If the (E) component content is 20 mass% or less, the via resolution, adhesive strength with plated copper, and electrical insulation reliability all tend to be sufficient.

[0096] ((E) Component Content) When the photosensitive resin composition of the present embodiment contains the component (E), its content is not particularly limited, but is preferably 0.01 to 5 mass%, more preferably 0.02 to 3 mass%, and even more preferably 0.03 to 2 mass% based on the total amount of the resin components of the photosensitive resin composition. If it is 0.01 mass% or more, sufficient heat curing tends to be achieved, and if it is 5 mass% or less, the photosensitive characteristics and heat resistance tend to be good.

[0097] <(F) Inorganic filler> The photosensitive resin composition of the present embodiment may contain an inorganic filler as the component (F), and preferably contains an inorganic filler. By containing an inorganic filler, the thermal expansion can be reduced, and the risk of warping is reduced. In the thermosetting resin composition that has been conventionally used as an interlayer insulating layer of a multilayer printed wiring board, the thermal expansion has been reduced by containing an inorganic filler, but when an inorganic filler is contained in a photosensitive resin composition, the inorganic filler causes light scattering and becomes an obstacle to development, so it was difficult to contain a large amount of inorganic filler to achieve low thermal expansion. Thus, there is a new problem unique to the photosensitive resin composition in containing an inorganic filler, but the photosensitive resin composition of the present embodiment tends to maintain high via resolution even if a large amount of inorganic filler is contained. Therefore, with the photosensitive resin composition of the present embodiment, it is possible to achieve both low thermal expansion and high via resolution.

[0098] Examples of the (F) component include silica (SiO2), alumina (Al2O3), titania (TiO2), tantalum oxide (Ta2O5), zirconia (ZrO2), silicon nitride (Si3N4), barium titanate (BaO·TiO2), barium carbonate (BaCO3), magnesium carbonate (MgCO3), aluminum hydroxide (Al(OH)3), magnesium hydroxide (Mg(OH)2), lead titanate (PbO·TiO2), lead zirconate titanate (PZT), lead lanthanum zirconate titanate (PLZT), gallium oxide (Ga2O3), spinel (MgO·Al2O 3), mullite (3Al2O3·2SiO2), cordierite (2MgO·2Al2O3 / 5SiO2), talc (3MgO·4SiO2·H2O), aluminum titanate (TiO2·Al2O3), yttria-containing zirconia (Y2O3·ZrO2), barium silicate (BaO·8SiO2), boron nitride (BN), calcium carbonate (CaCO3), barium sulfate (BaSO4), calcium sulfate (CaSO4), zinc oxide (ZnO), magnesium titanate (MgO·TiO2), hydrotalcite, mica, calcined kaolin, carbon, etc. (F) component may be used alone or in combination of two or more types.

[0099] From the viewpoints of heat resistance and low thermal expansion, the component (F) preferably contains silica, and more preferably is silica. The component (F) may be surface-treated with alumina or an organic silane compound from the viewpoint of improving the dispersibility of the inorganic filler in the photosensitive resin composition by the aggregation prevention effect.

[0100] From the viewpoint of via resolution, the average particle diameter of the (F) component is preferably 0.01 to 5 μm, more preferably 0.1 to 3 μm, even more preferably 0.1 to 2 μm, and particularly preferably 0.1 to 1 μm. Here, the average particle diameter of the (F) component is the volume average particle diameter of the inorganic filler in a state dispersed in the photosensitive resin composition, and is a value obtained by measuring as follows. First, the photosensitive resin composition is diluted (or dissolved) 1,000 times with methyl ethyl ketone, and then the particles dispersed in the solvent are measured at a refractive index of 1.38 using a submicron particle analyzer (manufactured by Beckman Coulter, Inc., product name: N5) in accordance with the international standard ISO13321, and the particle diameter at an integrated value of 50% (volume basis) in the particle size distribution is taken as the average particle diameter (volume average particle diameter). In addition, the (F) component contained in the photosensitive resin film and the interlayer insulating layer provided on the carrier film can also be measured by diluting (or dissolving) it 1,000 times (volume ratio) using a solvent as described above, and then using the submicron particle analyzer.

[0101] ((F) Component Content) When the photosensitive resin composition of the present embodiment contains the component (F), its content is not particularly limited, but is preferably 5 to 80 mass%, more preferably 15 to 60 mass%, further preferably 15 to 55 mass%, particularly preferably 20 to 50 mass%, and most preferably 30 to 45 mass%, based on the total solid content of the photosensitive resin composition. If the content of the component (F) is within the above range, the mechanical strength, heat resistance, via resolution, etc. can be improved.

[0102] <(G) Pigment> The photosensitive resin composition of the present embodiment may contain a pigment as component (G) according to the desired color in order to adjust photosensitivity, etc. As the component (G), a colorant that develops the desired color may be appropriately selected and used, and preferred examples thereof include known colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, carbon black, and naphthalene black.

[0103] ((G) Component Content) When the photosensitive resin composition of the present embodiment contains the component (G), the content thereof is preferably 0.01 to 5 mass %, more preferably 0.03 to 3 mass %, and even more preferably 0.05 to 2 mass %, based on the total solid content of the photosensitive resin composition, from the viewpoint of adjusting photosensitivity, etc.

[0104] <Diluent> A diluent may be used in the photosensitive resin composition of the present embodiment as necessary. As the diluent, for example, an organic solvent may be used. As the organic solvent, for example, ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, propylene glycol monoethyl ether acetate, butyl cellosolve acetate, and carbitol acetate; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha may be used. The diluent may be used alone or in combination of two or more. As the diluent, ketones and esters are preferable, and esters are more preferable.

[0105] (Diluent content) The content of the diluent may be appropriately selected so that the concentration of the total solid content in the photosensitive resin composition is preferably 40 to 90 mass%, more preferably 50 to 80 mass%, and further preferably 55 to 70 mass%. By adjusting the amount of the diluent used in this manner, the coatability of the photosensitive resin composition is improved, and a more precise pattern can be formed.

[0106] <Other ingredients> The photosensitive resin composition of the present embodiment may contain various known and commonly used additives, such as polymerization inhibitors such as hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, catechol, and pyrogallol; thickeners such as bentone and montmorillonite; foam stabilizers such as silicone-based foam stabilizers, fluorine-based foam stabilizers, and vinyl resin-based foam stabilizers; and silane coupling agents, as required. In addition, the composition may contain flame retardants such as brominated epoxy compounds, acid-modified brominated epoxy compounds, phosphate compounds of antimony compounds and phosphorus-based compounds, aromatic condensed phosphate esters, and halogen-containing condensed phosphate esters; and thermoplastic resins such as polyester polyurethane resins.

[0107] The photosensitive resin composition of the present embodiment can be obtained by kneading and mixing the components using a roll mill, a bead mill, or the like. Here, the photosensitive resin composition of the present embodiment may be used in the form of a liquid or a film. When used in a liquid form, the method for applying the photosensitive resin composition of the present embodiment is not particularly limited, and examples thereof include various application methods such as printing, spin coating, spray coating, jet dispensing, inkjet, dip coating, etc. Among these, from the viewpoint of more easily forming the photosensitive layer, the printing method or spin coating method may be appropriately selected. When used in the form of a film, it can be used in the form of a photosensitive resin film described later, for example, and in this case, a photosensitive layer of a desired thickness can be formed by laminating it on a carrier film using a laminator, etc. Note that using it in the form of a film is preferable because it increases the production efficiency of multilayer printed wiring boards.

[0108] [Photosensitive resin film, photosensitive resin film for interlayer insulation layer] The photosensitive resin film of the present embodiment is a photosensitive layer that will later become an interlayer insulating layer, and is made of the photosensitive resin composition of the present embodiment. The photosensitive resin film of the present embodiment may be in a form in which the photosensitive resin film is provided on a carrier film. The thickness (thickness after drying) of the photosensitive resin film (photosensitive layer) is not particularly limited, but from the viewpoint of thinning the multilayer printed wiring board, it is preferably 1 to 100 μm, more preferably 1 to 50 μm, and even more preferably 5 to 40 μm.

[0109] The photosensitive resin film of the present embodiment can be obtained, for example, by applying the photosensitive resin composition of the present embodiment onto a carrier film using a known coating device such as a comma coater, a bar coater, a kiss coater, a roll coater, a gravure coater, or a die coater, and drying the composition to form a photosensitive layer that will later become an interlayer insulating layer. Examples of the carrier film include polyester films such as polyethylene terephthalate film and polybutylene terephthalate film, and polyolefin films such as polypropylene film and polyethylene film. The thickness of the carrier film may be appropriately selected from the range of 5 to 100 μm, preferably 5 to 60 μm, and more preferably 15 to 45 μm.

[0110] In addition, the photosensitive resin film of this embodiment may have a protective film on the surface of the photosensitive layer opposite to the surface in contact with the carrier film. As the protective film, for example, a polymer film such as polyethylene or polypropylene may be used. In addition, the same polymer film as the carrier film described above may be used, or a different polymer film may be used.

[0111] The coating film formed by applying the photosensitive resin composition can be dried using a dryer using hot air drying, far infrared rays, or near infrared rays. The drying temperature is preferably 60 to 150°C, more preferably 70 to 120°C, and even more preferably 80 to 100°C. The drying time is preferably 1 to 60 minutes, more preferably 2 to 30 minutes, and even more preferably 5 to 20 minutes. The content of the remaining diluent in the photosensitive resin film after drying is preferably 3% by mass or less, more preferably 2% by mass or less, and even more preferably 1% by mass or less, from the viewpoint of preventing the diluent from diffusing in the manufacturing process of a multilayer printed wiring board.

[0112] The photosensitive resin film of the present embodiment is suitable as an interlayer insulating layer of a multilayer printed wiring board because it has excellent via resolution, adhesive strength with plated copper, electrical insulation reliability, and crack resistance. That is, the present invention also provides a photosensitive resin film for an interlayer insulating layer. The photosensitive resin film for an interlayer insulating layer can also be called an interlayer insulating photosensitive film.

[0113] [Multilayer printed wiring board and its manufacturing method] The present invention also provides a multilayer printed wiring board containing an interlayer insulating layer formed using the photosensitive resin composition or photosensitive resin film of the present embodiment. The multilayer printed wiring board of the present embodiment is not particularly limited in its manufacturing method as long as it includes a step of forming an interlayer insulating layer using the photosensitive resin composition of the present embodiment, and can be easily manufactured, for example, by the following manufacturing method of the multilayer printed wiring board of the present embodiment.

[0114] Hereinafter, as an example of a preferred embodiment of a method for manufacturing a multilayer printed wiring board, a method for manufacturing a multilayer printed wiring board using the photosensitive resin film of this embodiment (photosensitive resin film for interlayer insulating layer) will be described with reference to FIG. 1 as appropriate. Multilayer printed wiring board 100A can be manufactured, for example, by a manufacturing method including the following steps (1) to (4). Step (1): A step of laminating the photosensitive resin film of the present embodiment onto one or both sides of a circuit board (hereinafter, referred to as "lamination step (1)"). Step (2): A step of forming an interlayer insulating layer having vias by exposing and developing the photosensitive resin film laminated in step (1) (hereinafter referred to as "photovia forming step (2)"). Step (3): A step of subjecting the vias and the interlayer insulating layer to a roughening treatment (hereinafter referred to as "roughening treatment step (3)"). Step (4): A step of forming a circuit pattern on the interlayer insulating layer (hereinafter referred to as "circuit pattern forming step (4)").

[0115] (Lamination process (1)) The lamination step (1) is a step of laminating the photosensitive resin film of this embodiment (photosensitive resin film for interlayer insulating layer) onto one or both sides of a circuit board (substrate 101 having a circuit pattern 102) using a vacuum laminator. Examples of the vacuum laminator include a vacuum applicator manufactured by Nichigo-Morton Co., Ltd., a vacuum pressure laminator manufactured by Meiki Co., Ltd., a roll-type dry coater manufactured by Hitachi, Ltd., and a vacuum laminator manufactured by Hitachi Chemical Electronics Co., Ltd.

[0116] When a protective film is provided on the photosensitive resin film, after peeling or removing the protective film, the photosensitive resin film can be laminated by being pressed and heated onto the circuit board so that the photosensitive resin film is in contact with the circuit board. The lamination can be carried out, for example, after preheating the photosensitive resin film and the circuit board as necessary, under reduced pressure at a pressure bonding temperature of 70 to 130°C, a pressure bonding pressure of 0.1 to 1.0 MPa, and an air pressure of 20 mmHg (26.7 hPa) or less, but is not particularly limited to these conditions. The lamination method may be a batch method or a continuous method using a roll. Finally, the photosensitive resin film (hereinafter sometimes referred to as the photosensitive layer) laminated to the circuit board is cooled to about room temperature to form the interlayer insulating layer 103. The carrier film may be peeled off at this point, or may be peeled off after exposure as described below.

[0117] (Photovia formation process (2)) In the photovia forming process (2), at least a part of the photosensitive resin film laminated to the circuit board is exposed to light, and then developed. The exposed part is photocured to form a pattern. There is no particular limitation on the exposure method, and for example, a method of irradiating an image-wise pattern of active light through a negative or positive mask pattern called artwork (mask exposure method) may be adopted, or a method of irradiating an image-wise pattern of active light by a direct writing exposure method such as LDI (Laser Direct Imaging) exposure method or DLP (Digital Light Processing) exposure method may be adopted. Known light sources can be used as the light source of the actinic rays. Specific examples of light sources include gas lasers such as carbon arc lamps, mercury vapor arc lamps, high-pressure mercury lamps, xenon lamps, and argon lasers; solid-state lasers such as YAG lasers; and those that effectively emit ultraviolet rays or visible light such as semiconductor lasers. The exposure dose is appropriately selected depending on the light source used and the thickness of the photosensitive layer, and for example, in the case of ultraviolet irradiation from a high-pressure mercury lamp, the exposure dose is usually 10 to 1,000 mJ / cm for a photosensitive layer with a thickness of 1 to 100 μm. 2 The preferred range is 15 to 500 mJ / cm 2 is more preferred.

[0118] In the development, the uncured portions of the photosensitive layer are removed from the substrate, and an interlayer insulating layer made of a photocured product is formed on the substrate. When a carrier film is present on the photosensitive layer, the carrier film is removed before removing (developing) the unexposed portion. The developing method includes wet development and dry development, either of which may be adopted, but wet development is widely used and can be adopted in this embodiment as well. In the case of wet development, a developer corresponding to the photosensitive resin composition is used to develop the photosensitive resin composition by a known development method. Examples of the development method include a dip method, a paddle method, a spray method, brushing, slapping, scraping, and swing immersion. Among these, from the viewpoint of improving the resolution of the via, the spray method is preferred, and among the spray methods, the high-pressure spray method is more preferred. The development may be performed by one method, or may be performed by combining two or more methods. The composition of the developer is appropriately selected depending on the composition of the photosensitive resin composition. For example, an alkaline aqueous solution, a water-based developer, or an organic solvent-based developer may be used, and among these, an alkaline aqueous solution is preferred.

[0119] In the photovia forming process (2), after exposure and development, 0.2 to 10 J / cm 2 (preferably 0.5 to 5 J / cm 2 ) and post-thermal cure at a temperature of about 60 to 250°C (preferably 120 to 200°C) as necessary to further harden the interlayer insulating layer, and this is also preferable. In this manner, an interlayer insulating layer having vias 104 is formed. There are no particular limitations on the shape of the vias, and examples of the cross-sectional shape include a rectangle and an inverted trapezoid (where the upper side is longer than the lower side), and examples of the shape as viewed from the front (the direction in which the via bottom is visible) include a circle and a rectangle. In the formation of vias by photolithography in this embodiment, a via having a cross-sectional shape of an inverted trapezoid (where the upper side is longer than the lower side) can be formed, which is preferable because it increases the adhesion of plated copper to the via wall surface.

[0120] The size (diameter) of the via formed by this process can be 60 μm or less, and can also be less than 40 μm or 30 μm or less, which is smaller than the size of the via produced by laser processing. There is no particular lower limit to the size (diameter) of the via formed by this process, but it may be 15 μm or more, or 20 μm or more. However, the size (diameter) of the vias formed in this step is not necessarily limited to 60 μm or less, and may be, for example, about 200 μm or less, and can be arbitrarily selected within the range of, for example, 15 to 300 μm.

[0121] (Roughening treatment step (3)) In the roughening process (3), the surface of the via and the interlayer insulating layer is roughened with a roughening liquid. If a smear occurs in the photovia forming process (2), the smear may be removed with the roughening liquid. The roughening process and the removal of the smear can be performed simultaneously. Examples of the roughening solution include a chromium / sulfuric acid roughening solution, an alkaline permanganate roughening solution (for example, a sodium permanganate roughening solution), and a sodium fluoride / chromium / sulfuric acid roughening solution. The roughening treatment forms uneven anchors on the surface of the via and the interlayer insulating layer.

[0122] (Circuit pattern formation process (4)) The circuit pattern forming step (4) is a step of forming a circuit pattern on the interlayer insulating layer after the roughening treatment step (3). From the viewpoint of forming fine wiring, it is preferable to form the circuit pattern by a semi-additive process, which forms the circuit pattern and also provides electrical continuity of the vias. In the semi-additive process, first, the via bottom, via wall surface, and the entire surface of the interlayer insulating layer after the roughening treatment step (3) are subjected to electroless copper plating treatment using a palladium catalyst or the like to form a seed layer 105. The seed layer is for forming a power supply layer for electrolytic copper plating, and is preferably formed to a thickness of about 0.1 to 2.0 μm. If the seed layer is 0.1 μm or more thick, there is a tendency to suppress a decrease in connection reliability during electrolytic copper plating, and if it is 2.0 μm or less, there is no need to increase the amount of etching when flash etching the seed layer between wirings, and damage to wiring during etching tends to be suppressed.

[0123] The electroless copper plating process is carried out by reacting copper ions with a reducing agent to deposit metallic copper on the surface of the vias and the interlayer insulating layer. The electroless plating method and the electrolytic plating method may be known methods and are not particularly limited, but the catalyst in the electroless plating step is preferably a palladium-tin mixed catalyst, and the primary particle size of the catalyst is preferably 10 nm or less. In addition, the plating composition in the electroless plating step preferably contains hypophosphorous acid as a reducing agent. Commercially available electroless copper plating solutions can be used, and examples of such commercially available solutions include "MSK-DK" manufactured by Atotech Japan Co., Ltd. and "ThruCup (registered trademark) PEA ver. 4" series manufactured by Uemura Kogyo Co., Ltd.

[0124] After the electroless copper plating process, a dry film resist is heat-pressed onto the electroless copper plating using a roll laminator. The thickness of the dry film resist must be greater than the wiring height after electrolytic copper plating, and from this viewpoint, a dry film resist having a thickness of 5 to 30 μm is preferred. As the dry film resist, the "Photec" series manufactured by Hitachi Chemical Co., Ltd., or the like is used. After the dry film resist is thermocompression bonded, the dry film resist is exposed to light, for example, through a mask on which a desired wiring pattern is drawn. The exposure can be performed using the same device and light source as those that can be used when forming vias in the photosensitive resin film. After the exposure, the carrier film on the dry film resist is peeled off, and development is performed using an alkaline aqueous solution to remove the unexposed parts, forming a resist pattern 106. Thereafter, if necessary, a process of removing development residues of the dry film resist using plasma or the like may be performed. After development, copper electroplating is performed to form a copper circuit layer 107 and fill vias.

[0125] After the copper electroplating, the dry film resist is stripped off using an alkaline aqueous solution or an amine-based stripper. After the dry film resist is stripped off, the seed layer between the wirings is removed (flash etching). Flash etching is performed using an acidic solution such as sulfuric acid and hydrogen peroxide, and an oxidizing solution. Specific examples include "SAC" manufactured by JCU Corporation and "CPE-800" manufactured by Mitsubishi Gas Chemical Company, Inc. After flash etching, palladium and the like attached to the portions between the wirings is removed as necessary. Palladium can be removed preferably using an acidic solution such as nitric acid or hydrochloric acid.

[0126] After the dry film resist is peeled off or after the flash etching step, a post-baking process is preferably performed. The post-baking process sufficiently heat-cures unreacted thermosetting components, thereby improving the electrical insulation reliability, curing characteristics, and adhesive strength with plated copper. Although the heat-curing conditions vary depending on the type of resin composition, etc., it is preferable that the curing temperature is 150 to 240°C and the curing time is 15 to 100 minutes. The post-baking process completes a series of steps for manufacturing a printed wiring board using the photovia method, but this process is repeated depending on the number of interlayer insulating layers required to manufacture a board. Then, a solder resist layer 108 is preferably formed on the outermost layer.

[0127] The method for producing a multilayer printed wiring board in which vias are formed using the photosensitive resin composition of this embodiment has been described above, but since the photosensitive resin composition of this embodiment has excellent pattern resolution, it is also suitable for forming cavities for incorporating chips, passive elements, etc. The cavities can be suitably formed, for example, by selecting a drawing pattern that can form a desired cavity when forming a pattern by exposing the photosensitive resin film in the above description of the multilayer printed wiring board. Furthermore, the photosensitive resin composition of the present embodiment is also useful as a surface protective film for solder resist and the like.

[0128] [Semiconductor package] The present invention also provides a semiconductor package comprising a semiconductor element mounted on the multilayer printed wiring board of the present embodiment. The semiconductor package of the present embodiment can be manufactured by mounting a semiconductor element such as a semiconductor chip or memory at a predetermined position on the multilayer printed wiring board of the present invention and sealing the semiconductor element with a sealing resin or the like. EXAMPLES

[0129] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The properties of the photosensitive resin compositions obtained in the respective examples were evaluated by the methods described below.

[0130] [1. Evaluation of via resolution] (1-1) Preparation of Laminate for Evaluation The copper foil surface of a substrate for printed wiring boards (manufactured by Hitachi Chemical Co., Ltd., product name "MCL-E-679") consisting of 12 μm thick copper foil laminated to a glass epoxy base material was treated with a roughening treatment solution (manufactured by MEC Co., Ltd., product name "CZ-8100"), followed by rinsing with water and drying to obtain a roughened substrate for printed wiring boards. Next, the protective film was peeled off and removed from the "photosensitive resin film with the carrier film and the protective film laminated thereto" produced in each Example and Comparative Example, and the exposed photosensitive resin film was placed so as to be in contact with the copper foil of the substrate for printed wiring boards that had been roughened, and then a lamination process was performed using a press-type vacuum laminator (manufactured by Meiki Seisakusho Co., Ltd., product name "MVLP-500"). The lamination conditions were a press hot plate temperature of 70°C, a vacuuming time of 20 seconds, a lamination press time of 30 seconds, an atmospheric pressure of 4 kPa or less, and a pressure of 0.4 MPa. After the lamination process, the product was left at room temperature for 1 hour or more to obtain an evaluation laminate in which the photosensitive resin film and the carrier film were laminated in this order on the copper foil surface of the substrate for printed wiring boards. (1-2) Sensitivity measurement of photosensitive resin film After peeling and removing the carrier film of the evaluation laminate obtained in (1-1) above, a 41-step tablet was placed and exposed using a direct imaging exposure device "DXP-3512" (manufactured by Oak Manufacturing Co., Ltd.) with an ultra-high pressure mercury lamp as the light source. The exposure pattern used was a pattern in which dots were arranged in a lattice (dot diameter: distance between dot centers = 1:2). The dot diameter (φ) was changed in 5 μm increments within the range of 30 to 200 μm. After exposure, the film was left to stand at room temperature for 30 minutes, and then the unexposed portion of the photosensitive resin composition was spray-developed for 60 seconds using a 1% by mass aqueous solution of sodium carbonate at 30° C. After development, the amount of exposure energy at which the gloss remaining step number of the 41-step tablet was 8.0 was determined as the sensitivity of the photosensitive resin film (unit: mJ / cm 2 Using the pattern exposed at this sensitivity, the resolution of the vias provided in the photosensitive resin film was evaluated according to the following evaluation criteria. (1-3) Evaluation of via resolution The via resolution was evaluated by exposing the photosensitive resin film to an exposure energy amount that gave a step number of 8.0, measured in (1-2) above, and then spray developing. The via pattern was observed using an optical microscope and evaluated according to the following criteria. The "open" state mentioned above refers to a state in which the copper foil of the printed wiring board substrate can be confirmed when observing the via portion of the dot pattern using an optical microscope. A rating of "A" indicates good characteristics. A: The φ60 μm via part of the dot pattern is open. B: The φ200μm via part of the dot pattern is open. R . C: The φ200 μm via part of the dot pattern is not open.

[0131] [2. Evaluation of adhesive strength (peel strength) with plated copper] While peeling off the protective film from the "photosensitive resin film having a carrier film and a protective film laminated thereto" produced in each of the examples and comparative examples, lamination was performed on a copper-clad laminate substrate having a thickness of 1.0 mm using a press-type vacuum laminator (manufactured by Meiki Seisakusho Co., Ltd., product name "MVLP-500") at a pressure of 0.4 MPa, a press hot plate temperature of 80°C, a vacuum drawing time of 25 seconds, a lamination press time of 25 seconds, and an air pressure of 4 kPa or less to obtain a laminate. The obtained laminate was exposed to 500 mJ / cm using a parallel light exposure machine (manufactured by Oak Manufacturing Co., Ltd., product name "EXM-1201") using an ultra-high pressure mercury lamp as a light source. 2 Next, the entire surface was exposed to 2,000 mJ / cm using an ultraviolet exposure device. 2 and heated at 170° C. for 1 hour to obtain a laminate for evaluation in the form of a cured product (cured film) on the copper-clad laminate substrate.

[0132] Next, first, an aqueous solution of diethylene glycol monobutyl ether: 200 ml / L and sodium hydroxide: 5 g / L was prepared as a swelling liquid, and the evaluation laminate was immersed for 10 minutes while being heated to 60°C. Next, an aqueous solution of potassium permanganate: 60 g / L and sodium hydroxide: 40 g / L was prepared as a roughening liquid, and the evaluation laminate was immersed for 10 minutes while being heated to 60°C. Subsequently, an aqueous solution of neutralizing liquid (tin chloride (SnCl2): 30 g / L, hydrogen chloride: 300 ml / L) was prepared, and the evaluation laminate was immersed for 5 minutes while being heated to 40°C, to reduce potassium permanganate. In this manner, the surface of the cured evaluation laminate was desmeared. Next, the surface of the cured product of the desmeared evaluation laminate was treated with an alkaline cleaner "Cleaner Securigant 902" (trade name, manufactured by Atotech Japan Co., Ltd.) at 60°C for 5 minutes, followed by degreasing and cleaning. After cleaning, the desmeared cured product was treated with a pre-dip liquid "Pre-dip Neogant B" (trade name, manufactured by Atotech Japan Co., Ltd.) at 23°C for 1 minute. Thereafter, the cured product was treated with an activator liquid "Activator Neogant 834" (trade name, manufactured by Atotech Japan Co., Ltd.) at 35°C for 5 minutes, and then treated with a reducing liquid "Reducer Neogant WA" (trade name, manufactured by Atotech Japan Co., Ltd.) at 30°C for 5 minutes. The evaluation laminate thus obtained was placed in a chemical copper solution ("Basic Printganth MSK-DK", "Copper Printganth MSK", "Stabilizer Printganth MSK" (all product names manufactured by Atotech Japan Co., Ltd.)) and electroless plating was carried out until the plating thickness reached approximately 0.5 μm. After the electroless plating, an annealing treatment was carried out at a temperature of 120°C for 30 minutes in order to remove any remaining hydrogen gas. Thereafter, copper sulfate electrolytic plating was carried out, followed by an annealing treatment at 180°C for 60 minutes to form a conductor layer with a thickness of 25 μm.

[0133] The laminate for evaluation having the conductor layer formed thereon as described above was measured for perpendicular peel strength at 23° C. in accordance with JIS C6481 (1996), and was evaluated according to the following evaluation criteria. A: The adhesive strength with plated copper was 0.40 kN / m or more. B: The adhesive strength with plated copper was 0.20 kN / m or more and less than 0.40 kN / m. C: The adhesive strength to plated copper was less than 0.20 kN / m.

[0134] [3. Measurement of surface roughness (Ra) after roughening treatment] The laminate having the conductor layer formed thereon, which was produced in the above [2. Evaluation of adhesive strength (peel strength) with plated copper], was immersed in a 10 mass % aqueous solution of ammonium persulfate to remove the formed conductor layer. The surface roughness (Ra) of the insulating layer was measured using a non-contact surface roughness meter (Beeco Instruments' "WYKO NT3300") in VSI contact mode with a 50x lens to obtain a measurement range of 121μm×92μm. The arithmetic mean roughness after roughening treatment was calculated from the values ​​obtained. The average value of 10 points was taken as the measured value. Evaluation was also conducted according to the following evaluation criteria. A: Ra after the roughening treatment was less than 200 nm. B: Ra after the roughening treatment was 200 nm or more and less than 500 nm. C: Ra after roughening treatment was 500 nm or more.

[0135] [4. Evaluation of HAST resistance (electrical insulation reliability after moisture absorption)] The same procedure was carried out as in the above [2. Evaluation of adhesive strength (peel strength) with plated copper], except that instead of forming a conductor layer with a thickness of 25 μm, a conductor layer with a thickness of 35 μm was formed, thereby obtaining a laminate with a conductor layer formed thereon. The conductive layer thus formed was etched to form a circular electrode having a diameter (φ) of 6 mm. A photosensitive solder resist film "FZ-2700GA" (Hitachi Chemical Co., Ltd., product name) was then formed on the electrode and the cured film to a thickness of 25 μm using a press-type vacuum laminator (Meiki Seisakusho Co., Ltd., product name "MVLP-500") at a pressure of 0.4 MPa, a press hot plate temperature of 80°C, a vacuuming time of 25 seconds, a lamination press time of 40 seconds, and an atmospheric pressure of 4 kPa or less to obtain a laminate for evaluation.

[0136] The laminate for evaluation obtained as described above was exposed to 500 mJ / cm 2 using a parallel light exposure machine (manufactured by Oak Manufacturing Co., Ltd., product name "EXM-1201") using an ultra-high pressure mercury lamp as a light source. 2 Next, the entire surface was exposed to 2,000 mJ / cm using an ultraviolet exposure device. 2 and heated at 160° C. for 1 hour to obtain a cured film. Next, wiring was performed so that the circular electrode was the positive electrode and the copper foil on the side of the copper-clad laminate where the circular electrode was formed was the negative electrode, and the specimen was exposed to conditions of 135°C, 85%, and 5.5 V for 200 hours using a pressure cooker (model name: "Unsaturated Type Ultra-Accelerated Life Tester PC-422RP", manufactured by Hirayama Seisakusho Co., Ltd.). The resistance between the electrodes was measured and evaluated according to the following evaluation criteria. A: Resistance after 200 hours is 10 x 10 7 It was more than Ω. B: Resistance after 200 hours is 10 x 10 6 Ω or more and 10×10 7 It was less than Ω. C: Resistance after 200 hours is 10 x 10 6 It was less than Ω.

[0137] <Synthesis Example 1> Synthesis of acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative 1 [component (A1-1)] 350 parts by mass of a dicyclopentadiene type epoxy resin ("XD-1000" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 252 g / eq, softening point 74.2°C, corresponding to component (a1) and represented by general formula (a1-1) above; number of ring-forming carbon atoms in the alicyclic skeleton: 10), 70 parts by mass of acrylic acid (corresponding to component (a2)), 0.5 parts by mass of methylhydroquinone, and 120 parts by mass of carbitol acetate were charged and reacted by heating to 90°C and stirring, thereby dissolving the mixture. Next, the obtained solution was cooled to 60° C., 2 parts by mass of triphenylphosphine was added, and the solution was heated to 100° C. and reacted until the acid value of the solution reached 1 mgKOH / g. To the reacted solution, 98 parts by mass of tetrahydrophthalic anhydride (corresponding to component (a3)) and 85 parts by mass of carbitol acetate were added, and the solution was heated to 80° C. and reacted for 6 hours. Thereafter, it was cooled to room temperature to obtain an acid-modified dicyclopentadiene-type epoxy acrylate having a solid content of 73 mass % (corresponding to component (A1-1). Hereinafter, this is referred to as "acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative 1").

[0138] <Synthesis Example 2> Synthesis of acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative 2 [component (A1-1)] 350 parts by mass of a dicyclopentadiene type epoxy resin (EPICLON (registered trademark) HP-7200 manufactured by DIC Corporation, epoxy equivalent 254 to 264 g / eq, softening point 56 to 66° C., corresponds to component (a1) and is represented by the general formula (a1-1) above. Number of ring carbon atoms in the alicyclic skeleton: 10), 70 parts by mass of acrylic acid (corresponding to component (a2)), 0.5 parts by mass of methyl hydroquinone, and 120 parts by mass of carbitol acetate were charged and reacted by heating to 90° C. and stirring, thereby dissolving the mixture. Next, the obtained solution was cooled to 60° C., 2 parts by mass of triphenylphosphine was added, and the solution was heated to 100° C. and reacted until the acid value of the solution reached 1 mgKOH / g. To the reacted solution, 98 parts by mass of tetrahydrophthalic anhydride (corresponding to component (a3)) and 85 parts by mass of carbitol acetate were added, and the solution was heated to 80° C. and reacted for 6 hours. Thereafter, it was cooled to room temperature to obtain an acid-modified dicyclopentadiene-type epoxy acrylate having a solid content of 74 mass % (corresponding to component (A1-1). Hereinafter, this is referred to as "acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative 2").

[0139] <Synthesis Example 3> (A2-1) Synthesis of an acid-modified ethylenically unsaturated group-containing epoxy derivative not containing an alicyclic skeleton 350 parts by mass of bisphenol F novolac epoxy resin ("EXA-7376" manufactured by DIC Corporation, corresponding to component (a21)), 70 parts by mass of acrylic acid (corresponding to component (a22)), 0.5 parts by mass of methyl hydroquinone, and 120 parts by mass of carbitol acetate were charged and reacted by heating to 90°C and stirring to dissolve the mixture. Next, the obtained solution was cooled to 60°C, 2 parts by mass of triphenylphosphine was added, and the solution was heated to 100°C and reacted until the acid value of the solution reached 1 mgKOH / g. To the reacted solution, 98 parts by mass of tetrahydrophthalic anhydride (corresponding to component (a23)) and 85 parts by mass of carbitol acetate were added, and the solution was heated to 80°C and reacted for 6 hours. Thereafter, the mixture was cooled to room temperature to obtain an acid-modified bisphenol F type epoxy acrylate having a solid content of 73 mass % (corresponding to component (A2-1). Hereinafter, this is referred to as "acid-modified ethylenically unsaturated group-containing epoxy derivative 3 not containing an alicyclic skeleton").

[0140] <Examples 1 to 8 and Comparative Examples 1 to 4> (Preparation of Photosensitive Resin Composition) Photosensitive resin compositions were prepared by mixing the compositions according to the compositions and amounts shown in Table 1 using a three-roll mill. In each example, carbitol acetate was appropriately added to adjust the concentration, and a photosensitive resin composition with a solid content of 60% by mass was obtained. (Preparation of photosensitive resin film) A polyethylene terephthalate film (G2-25, Teijin Limited, product name) having a thickness of 25 μm was used as a carrier film, and the photosensitive resin composition prepared in each example was applied onto the carrier film so that the film thickness after drying was 25 μm, and dried at 100° C. for 10 minutes using a hot air convection dryer to form a photosensitive resin film (photosensitive layer). Next, a biaxially oriented polypropylene film (MA-411, Oji F-Tex Co., Ltd., product name) was laminated as a protective film on the surface of the photosensitive resin film (photosensitive layer) opposite to the side in contact with the carrier film, to produce a photosensitive resin film in which the carrier film and the protective film were laminated together. The photosensitive resin film thus produced was subjected to the evaluations according to the above-mentioned methods. The results are shown in Table 1.

[0141] [Table 1]

[0142] The components used in each example are as follows: (A) component; Acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative 1 [component (A1-1)]: the one obtained in Synthesis Example 1 was used. Acid-modified ethylenically unsaturated group and alicyclic skeleton-containing epoxy derivative 2 [component (A1-1)]: the one obtained in Synthesis Example 2 was used. Acid-modified ethylenically unsaturated group-containing epoxy derivative 3 not containing an alicyclic skeleton [component (A2-1)]: the one obtained in Synthesis Example 3 was used. Dipentaerythritol pentaacrylate [ingredient (Aiii)] (B) Ingredients; Photopolymerization initiator 1: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, acetophenones Photopolymerization initiator 2: 2,4-diethylthioxanthone, thioxanthones (C) Component; Benzoxazine resin "Pd-type benzoxazine" (product name, manufactured by Shikoku Chemical Industry Co., Ltd.) Benzoxazine resin "Fa-type benzoxazine" (product name, manufactured by Shikoku Chemical Industry Co., Ltd.) (D) Component; Biphenyl type epoxy resin: "YX-4000" (product name, manufactured by Mitsubishi Chemical Corporation) (E) Ingredients; Polyester elastomer: "Espel (registered trademark) 1108" (product name, manufactured by Hitachi Chemical Co., Ltd.) (F) component; Silica: "SFP-20M" (product name, manufactured by Denka Co., Ltd., average particle size 0.3 μm)

[0143] As can be seen from Table 1, in Examples 1 to 8, the via resolution was excellent, the adhesive strength with plated copper was high despite the low roughness, and the electrical insulation reliability was excellent. In addition, since the surface roughness Ra of the interlayer insulating layer made of the photosensitive resin composition was small, a fine surface shape could be formed on the surface of the interlayer insulating layer, and fine wiring tends to be easily formed. On the other hand, in Comparative Examples 1 to 3, which did not contain component (C), the adhesive strength with plated copper at low roughness was insufficient, and in Comparative Example 4, which contained component (C) but not component (D), the adhesive strength with plated copper at low roughness was insufficient and the electrical insulation reliability was significantly reduced. [Explanation of symbols]

[0144] 100A Multilayer Printed Wiring Board 102 Circuit Pattern 103 Interlayer insulation layer 104 Beer (Beer Hall) 105 Seed Layer 106 Resist Pattern 107 Copper circuit layer 108 Solder resist layer

Claims

1. A photosensitive resin composition comprising: (A) a photopolymerizable compound having an ethylenically unsaturated group and not containing a urethane bond; (B) a photopolymerization initiator; (C) a benzoxazine compound; and (D) a thermosetting resin, The photosensitive resin composition according to claim 1, wherein the (A) photopolymerizable compound having an ethylenically unsaturated group and no urethane bond comprises (A1) a photopolymerizable compound having an ethylenically unsaturated group as well as an acidic substituent and an alicyclic skeleton, and no urethane bond, and the (A1) component is (A1-1) an acid-modified ethylenically unsaturated group- and alicyclic skeleton-containing epoxy derivative obtained by reacting (a1) an alicyclic skeleton-containing epoxy resin modified with (a2) an ethylenically unsaturated group-containing organic acid with (a3) ​​a saturated group- or unsaturated group-containing polybasic acid anhydride.

2. 2. The photosensitive resin composition according to claim 1, wherein the benzoxazine compound (C) has 1 to 3 benzoxazine rings in its molecular structure.

3. The photosensitive resin composition according to claim 1 or 2, wherein the (C) benzoxazine compound is a benzoxazine compound represented by any one of the following general formulas (C-1) to (C-3): 【Chemistry 1】 (In the formula, R ｃ１ and R ｃ２ are each independently a hydrocarbon group having 1 to 10 carbon atoms. ｃ１ is an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 2 to 5 carbon atoms, -O-, a sulfonyl group, a carbonyloxy group, -C(=O)-, or a single bond. ｃ１ and n ｃ２ are each independently an integer from 0 to 4. 【Chemistry 2】 (In the formula, R ｃ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms. ｃ４ are each independently a hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. ｃ２ is an alkylene group having 1 to 5 carbon atoms, an alkylidene group having 2 to 5 carbon atoms, -O-, a sulfonyl group, a carbonyloxy group, -C(=O)-, or a single bond. ｃ３ are each independently an integer from 0 to 3. 【Chemistry 3】 (In the formula, R ｃ５ is a hydrocarbon group having 1 to 10 carbon atoms. ｃ６ is a hydrocarbon group having 1 to 10 carbon atoms or a hydrogen atom. ｃ４ is an integer from 0 to 4.

4. The photosensitive resin composition according to any one of claims 1 to 3, wherein the content of the benzoxazine compound (C) is 0.5 to 30 mass% based on the total solid content of the photosensitive resin composition.

5. The photosensitive resin composition according to any one of claims 1 to 4, wherein in the photopolymerizable compound (A1) which has an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group, and does not contain a urethane bond, the alicyclic skeleton is an alicyclic skeleton having 5 to 20 ring carbon atoms.

6. The photosensitive resin composition according to any one of claims 1 to 5, wherein in the photopolymerizable compound (A1) which has an acidic substituent and an alicyclic skeleton together with an ethylenically unsaturated group, and does not contain a urethane bond, the alicyclic skeleton has two or more rings.

7. The photosensitive resin composition according to any one of claims 1 to 6, wherein the photopolymerizable compound (A) having an ethylenically unsaturated group and not containing a urethane bond further comprises at least one selected from the group consisting of (Ai) a monofunctional vinyl monomer having one polymerizable ethylenically unsaturated group, (Aii) a difunctional vinyl monomer having two polymerizable ethylenically unsaturated groups, and (Aiii) a polyfunctional vinyl monomer having at least three polymerizable ethylenically unsaturated groups.

8. The photosensitive resin composition according to any one of claims 1 to 7, wherein the (D) thermosetting resin is at least one selected from the group consisting of an epoxy resin, a phenolic resin, an unsaturated imide resin, a cyanate resin, an isocyanate resin, an oxetane resin, an amino resin, an unsaturated polyester resin, an allyl resin, a dicyclopentadiene resin, a silicone resin, a triazine resin, and a melamine resin.

9. The photosensitive resin composition according to any one of claims 1 to 8, further comprising (E) an elastomer.

10. 10. The photosensitive resin composition according to claim 9, wherein the (E) elastomer comprises at least one selected from the group consisting of a styrene-based elastomer, an olefin-based elastomer, a polyester-based elastomer, a urethane-based elastomer, a polyamide-based elastomer, an acrylic-based elastomer, and a silicone-based elastomer.

11. The photosensitive resin composition according to any one of claims 1 to 10, further comprising (F) an inorganic filler.

12. A photosensitive resin composition for forming a photovia, comprising the photosensitive resin composition according to any one of claims 1 to 11.

13. A photosensitive resin composition for an interlayer insulating layer, comprising the photosensitive resin composition according to any one of claims 1 to 11.

14. A photosensitive resin film comprising the photosensitive resin composition according to any one of claims 1 to 11.

15. A photosensitive resin film for an interlayer insulating layer, comprising the photosensitive resin composition according to any one of claims 1 to 11.

16. A multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin composition according to any one of claims 1 to 11.

17. A multilayer printed wiring board comprising an interlayer insulating layer formed using the photosensitive resin film according to claim 14.

18. A semiconductor package comprising the multilayer printed wiring board according to claim 16 or 17 mounted with a semiconductor element.

19. A method for producing a multilayer printed wiring board, comprising the following steps (1) to (4): Step (1): A step of laminating the photosensitive resin film according to claim 14 onto one or both sides of a circuit board. Step (2): A step of forming an interlayer insulating layer having vias by exposing and developing the photosensitive resin film laminated in the step (1). Step (3): A step of roughening the via and the interlayer insulating layer. Step (4): forming a circuit pattern on the interlayer insulating layer.

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