Photosensitive element, method for forming resist pattern, and method for manufacturing printed wiring board

Abstract

The invention relates to a photosensitive element, a method for forming a resist pattern, and a method for manufacturing a printed wiring board. The photosensitive element is provided with a support film, a barrier layer, and a photosensitive layer in this order, and in the photosensitive element, the barrier layer contains a water-soluble resin and an ultraviolet absorber.

Description

[0001] This application is a divisional application of Chinese application No. 201980029641.0, whose application date is May 8, 2019 and whose invention name is "Photosensitive element, resin composition for forming a barrier layer, method for forming a resist pattern and method for manufacturing a printed wiring board". Technical Field

[0002] The present invention relates to a photosensitive element, a method for forming a resist pattern, and a method for manufacturing a printed wiring board. Background Art

[0003] Conventionally, in the field of printed wiring board manufacturing, photosensitive resin compositions and photosensitive elements having a layer formed using the photosensitive resin composition on a support film (hereinafter also referred to as a "photosensitive layer") are widely used as resist materials used in etching processes or plating processes.

[0004] The printed wiring board uses the above-mentioned photosensitive element and is manufactured by, for example, the following steps. That is, first, the photosensitive layer of the photosensitive element is laminated on a circuit forming substrate such as a copper-clad laminate. At this time, the lamination is performed in a manner that the surface of the photosensitive layer opposite to the surface in contact with the support film is in close contact with the circuit forming surface of the circuit forming substrate. In addition, the lamination is performed, for example, by heating and pressing the photosensitive layer on the circuit forming substrate (normal pressure lamination method).

[0005] Next, using a mask film or the like, the desired area of ​​the photosensitive layer is exposed across the support film, thereby generating free radicals. The generated free radicals contribute to the crosslinking reaction (photocuring reaction) of the photopolymerizable compound through several reaction pathways. Next, after the support film is peeled off, the uncured portion of the photosensitive layer is dissolved or dispersed and removed using a developer to form a resist pattern. Next, using the resist pattern as a resist, an etching process or a plating process is performed to form a conductor pattern, and finally the photocured portion (resist pattern) of the photosensitive layer is peeled off (removed).

[0006] However, in recent years, a method of forming an excellent resist pattern by exposing the photosensitive layer after peeling off the support film before exposure has been studied. However, when the photosensitive layer is exposed after peeling off the support film, the free radicals generated are contacted with oxygen in the air, and the free radicals are rapidly stabilized (deactivated), which makes it difficult for the photopolymerizable compound to undergo a photocuring reaction. Therefore, in this method, in order to reduce the influence of oxygen mixing when the support film is peeled off and exposed, a photosensitive element having a barrier layer (intermediate layer) with gas barrier properties between the support film and the photosensitive layer is being studied (for example, refer to patent documents 1 to 3).

[0007] Previous technical literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent No. 5483734

[0010] Patent Document 2: Japanese Patent Application Publication No. 2013-24913

[0011] Patent Document 3: Japanese Patent No. 5551255 Summary of the invention

[0012] Technical issues to be solved by the invention

[0013] As a method for exposing the photosensitive layer, an exposure method using a projection exposure machine is used to achieve high resolution. This exposure method is a method of using active light rays with an image of a photomask projected thereon and irradiating in an image-like manner through a lens. The exposure method using a projection exposure machine can also be applied to a photosensitive element having a barrier layer containing a water-soluble resin as described in the above-mentioned patent documents 1 to 3. However, a projection exposure machine usually uses a high-intensity lamp, so there is a problem that it is difficult to obtain high resolution without reducing the sensitivity of the photosensitive layer to be exposed. It is believed that the reason is that if the sensitivity of the photosensitive layer is too high, excess free radicals are generated by exposure, the molecular chain length of the cured product is easily shortened, and this cured product is easily dispersed in the developer.

[0014] Conventionally, as a method for reducing the sensitivity of a photosensitive layer, there have been reported methods such as increasing the amount of a reaction inhibitor such as a polymerization inhibitor added to the photosensitive layer or reducing the amount of a photopolymerization initiator or a photosensitizer added to the photosensitive layer.

[0015] However, generally speaking, polymerization inhibitors with high resolution-enhancing capabilities have many low-molecular components and are easily volatilized during the drying process of manufacturing photosensitive elements, so it is difficult to obtain stable sensitivity in methods such as increasing the amount of polymerization inhibitors. In addition, in methods such as reducing the photopolymerization initiator component, the shape of the formed resist deteriorates after patterning and the amount of residue at the bottom of the resist changes, so there is a problem of difficulty in adjustment.

[0016] The present invention has been completed in view of the problems of the above-mentioned prior art, and its purpose is to provide a photosensitive element, a resin composition for forming a barrier layer, a method for forming an anti-etching pattern, and a method for manufacturing a printed wiring board, which can appropriately reduce the sensitivity and improve the resolution even without increasing the amount of a polymerization inhibitor or reducing the amount of a photopolymerization initiator.

[0017] Means for solving technical problems

[0018] To achieve the above object, the present invention provides a photosensitive element comprising a support film, a barrier layer, and a photosensitive layer in this order, wherein in the photosensitive element, the barrier layer contains a water-soluble resin and an ultraviolet absorber.

[0019] The photosensitive element of the present invention contains an ultraviolet absorber in the barrier layer, so that even if the amount of polymerization inhibitor is not increased or the amount of photopolymerization initiator is not decreased, the sensitivity can be appropriately reduced and the resolution can be improved. According to the photosensitive element, even if a high-illuminance projection exposure machine is used, exposure can be performed at an optimal sensitivity, so the reduction in resolution can be suppressed. In addition, since the resolution can be improved even without increasing the amount of polymerization inhibitor used, the sensitivity instability of the photosensitive element can be suppressed. Therefore, it can be said that by using the photosensitive element of the present invention, a resist pattern with excellent resolution can be formed.

[0020] In the photosensitive element of the present invention, the ultraviolet absorber may contain a benzophenonesulfonic acid compound or a compound represented by the following formula (1). According to this photosensitive element, the resolution can be further improved.

[0021] [Chemical formula 1]

[0022]

[0023] In the photosensitive element of the present invention, the solubility of the ultraviolet absorber in water at 20° C. may be 0.1 g / 100 mL-H2O or more. This photosensitive element can further suppress the generation of aggregates or precipitates in the barrier layer, thereby providing a photosensitive element excellent in practical use.

[0024] In the photosensitive element of the present invention, the content of the ultraviolet absorber in the barrier layer may be more than 0% by mass and 10.0% by mass or less based on the total amount of the barrier layer.

[0025] In the photosensitive element of the present invention, the ultraviolet absorption rate of the blocking layer may be 5 to 95%.

[0026] In the photosensitive element of the present invention, the water-soluble resin may include polyvinyl alcohol. According to this photosensitive element, the gas barrier property of the barrier layer can be further improved, and the deactivation of radicals generated by active light used in exposure can be further suppressed.

[0027] In the photosensitive element of the present invention, the support film may be a polyester film. According to the photosensitive element, the mechanical strength and heat resistance of the support film can be improved, and defects such as wrinkles of the barrier layer generated when the barrier layer is formed on the support film can be suppressed, thereby improving workability.

[0028] Furthermore, the present invention provides a barrier layer-forming resin composition comprising a water-soluble resin, an ultraviolet absorber, and water.

[0029] In the barrier layer forming resin composition of the present invention, the ultraviolet absorber may include a benzophenonesulfonic acid compound or a compound represented by the following formula (1). According to the barrier layer forming resin composition, the resolution can be further improved.

[0030] [Chemical formula 2]

[0031]

[0032] In the barrier layer forming resin composition of the present invention, the solubility of the ultraviolet absorber in water at 20° C. can be 0.1 g / 100 mL-H2O or more. According to the barrier layer forming resin composition, the generation of agglomerates or precipitates in the obtained barrier layer can be further suppressed, thereby forming a barrier layer excellent in practical use.

[0033] In the barrier layer-forming resin composition of the present invention, the content of the ultraviolet absorber may be 0.1 to 10.0 parts by mass based on 500 parts by mass of the water.

[0034] The barrier layer-forming resin composition of the present invention may have an ultraviolet absorption rate of 5 to 95% when formed into a dry film having a thickness of 5 μm.

[0035] In the barrier layer-forming resin composition of the present invention, the water-soluble resin may include polyvinyl alcohol. According to the barrier layer-forming resin composition, a barrier layer having more excellent gas barrier properties can be formed.

[0036] The present invention also provides a method for forming a resist pattern, comprising: using the photosensitive element of the present invention, sequentially arranging a photosensitive layer, a barrier layer, and a support film on a substrate from the substrate side; removing the support film and exposing the photosensitive layer to active light through the barrier layer; and removing the uncured portion of the photosensitive layer and the barrier layer from the substrate. According to the method for forming a resist pattern, the resist pattern is formed using the photosensitive element of the present invention, so that a resist pattern with excellent resolution can be formed.

[0037] In addition, the present invention also provides a method for manufacturing a printed wiring board, which includes: etching or plating a substrate on which a resist pattern is formed by the method for forming a resist pattern of the present invention, thereby forming a conductor pattern. According to the method for manufacturing a printed wiring board, a resist pattern is formed by the method for forming a resist pattern of the present invention, so that a method for manufacturing a printed wiring board that can form a resist pattern with excellent resolution and is suitable for high-densification of printed wiring boards can be provided.

[0038] Effects of the Invention

[0039] According to the present invention, there can be provided a photosensitive element, a resin composition for forming a barrier layer, a method for forming a resist pattern, and a method for manufacturing a printed wiring board, which can appropriately reduce sensitivity and improve resolution without increasing the amount of a polymerization inhibitor or reducing the amount of a photopolymerization initiator. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic cross-sectional view showing one embodiment of the photosensitive element of the present invention.

[0041] Figure 2 This is a diagram schematically showing an example of a process for producing a printed wiring board using a semi-additive method. DETAILED DESCRIPTION

[0042] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings as required. In the following embodiments, except for the cases specifically indicated and the cases considered to be obviously necessary in principle, the constituent elements (including element steps, etc.) are not essential. This is also true for numerical values ​​and their ranges, and should be interpreted as not unduly limiting the present invention.

[0043] In addition, in this specification, the so-called (meth) acrylic acid refers to at least one of acrylic acid and its corresponding methacrylic acid. And, the same applies to other similar expressions such as (meth) acrylates. Unless otherwise specified, the materials exemplified below can be used alone or in combination of two or more. Regarding the content of each component in the composition, when there are multiple substances corresponding to each component in the composition, unless otherwise specified, it refers to the total amount of the multiple substances present in the composition.

[0044] Furthermore, in the present specification, the term "step" refers not only to an independent step but also to a step that cannot be clearly distinguished from other steps as long as the intended effect of the step is achieved.

[0045] In addition, in this specification, the numerical range represented by "~" represents a range that includes the numerical values ​​recorded before and after "~" as the minimum and maximum values, respectively. Furthermore, in the numerical range recorded in stages in this specification, the upper limit value or lower limit value of the numerical range of a certain stage can be replaced by the upper limit value or lower limit value of the numerical range of other stages. Furthermore, in the numerical range recorded in this specification, the upper limit value or lower limit value of the numerical range can be replaced by the value shown in the embodiment. Furthermore, in this specification, the term "layer" includes partially formed shape structures in addition to the shape structures formed on the entire surface when observed as a plan view.

[0046] [Photosensitive element]

[0047] like Figure 1 As shown in FIG. 1 , the photosensitive element 1 of the present embodiment includes a support film 2, a barrier layer 3, and a photosensitive layer 4 in order, and may further include other layers such as a protective layer 5. In addition, the barrier layer contains a water-soluble resin and an ultraviolet absorber. By using the photosensitive element of the present embodiment, the barrier layer can absorb exposure light, optimize sensitivity, and improve resolution, so it is excellent in practical application. Hereinafter, each layer in the photosensitive element involved in the present embodiment will be described in detail.

[0048] <Support film>

[0049] As the support film of the present embodiment, it can be used without particular limitation. For example, polyester films such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and polyethylene 2,6-naphthalate (PEN), and polyolefin films such as polypropylene and polyethylene can be cited. Among them, polyester film can be used. By using polyester film as a support film, there is a tendency to improve the mechanical strength and heat resistance of the support film. In addition, by using polyester film, there is a tendency to suppress the wrinkles of the barrier layer generated when the barrier layer is formed on the support film, which can improve the workability. In addition, from the viewpoint of being able to suppress the generation of tiny detachment of the resist pattern, a polyester film containing particles (lubricant, etc.) can be used. In the case of using a polyester film containing particles (lubricant, etc.), a barrier layer can be formed on the surface having the particles (lubricant, etc.) on one side. As such a polyester film, for example, a polyester film into which particles (lubricant, etc.) are kneaded, a polyester film having layers containing particles (lubricant, etc.) formed on both sides, or a polyester film having a layer containing particles (lubricant, etc.) formed on one side can be used. In addition, the support film may be a single layer or a multilayer.

[0050] As a method for adding particles such as a lubricant to a support film, for example, there can be listed: a method of kneading particles (lubricant, etc.) into the support film; a method of forming a layer containing particles (lubricant, etc.) on the support film using a known method such as roller coating, flow coating, spray coating, curtain flow coating, dip coating, and slit die coating.

[0051] The haze of the support film may be 0.01 to 5.0%, 0.01 to 1.5%, 0.01 to 1.0% or 0.01 to 0.5%. When the haze is 0.01% or more, there is a tendency that the support film itself is easy to manufacture. If it is 5.0% or less, when the photosensitive layer of the photosensitive element is formed, there is a tendency that foreign matter in the photosensitive layer is easy to detect. Here, the so-called "haze" refers to turbidity. The haze in the present invention refers to the value measured using a commercially available turbidity meter (turbidimeter) according to the method specified in JIS K7105. The haze can be measured, for example, using a commercially available turbidity meter such as NDH-5000 (manufactured by Nippon Denshoku Industries Co., Ltd., trade name).

[0052] Furthermore, the support film can be obtained from commercially available general industrial films that can be used as a support film for a photosensitive element, and can be used after being appropriately processed. Specifically, for example, PET films include "FB-40" (manufactured by Toray Co., Ltd., product name), "A4100", "A1517" (manufactured by Toyobo Co., Ltd., product name), and "G2H" (manufactured by Teijin DuPont Films Co., Ltd., product name).

[0053] The thickness of the support film may be 1 to 200 μm, 1 to 100 μm, 1 to 60 μm, 5 to 60 μm, 10 to 60 μm, 10 to 50 μm, 10 to 40 μm, 10 to 30 μm or 10 to 25 μm. When the thickness of the support film is 1 μm or more, there is a tendency to suppress the support film from being damaged when peeling the support film. In addition, when the thickness of the support film is 200 μm or less, there is a tendency to easily obtain economic benefits.

[0054] <Barrier layer>

[0055] The photosensitive element of the present embodiment has a barrier layer between the support film and the photosensitive layer. And the barrier layer contains a water-soluble resin and an ultraviolet absorber. According to the photosensitive element of the present embodiment, even if the amount of the polymerization inhibitor added to the photosensitive layer is not increased, the barrier layer can be used to absorb the exposure light and become the best sensitivity, so when the photosensitive layer is exposed through the barrier layer after the support film is peeled off, the resolution of the formed resist pattern can be suppressed. The barrier layer can be a layer formed by using the barrier layer forming resin composition of the present embodiment described later. The barrier layer forming resin composition of the present embodiment contains a water-soluble resin, an ultraviolet absorber and water. And the barrier layer can be water-soluble and can also be soluble in a developer. In addition, from the perspective of being able to further improve the gas barrier properties based on the barrier layer, the adhesion between the support film and the barrier layer can be less than the adhesion between the barrier layer and the photosensitive layer. That is, it can also be said that when the support film is peeled off from the photosensitive element, the unintentional peeling of the barrier layer and the photosensitive layer is suppressed.

[0056] (Water-soluble resin)

[0057] Here, the so-called "water-soluble resin" refers to a resin having a solubility of 5 g / 100 mL in 100 mL of hexane at 25°C. 14 The following resin. The solubility can be calculated by mixing 25°C hexane with a dried water-soluble resin and checking whether there is white turbidity. Specifically, prepare sample 1 and sample 2, respectively. Sample 1 is obtained by placing a mixed liquid of dried water-soluble resin A (g) and 100 mL of hexane in a colorless and transparent glass container with a frosted glass stopper, and sample 2 is obtained by placing only 100 mL of hexane in a colorless and transparent glass container with a frosted glass stopper. Next, shake and mix the sample in the glass container thoroughly, and confirm that the foam disappears. Immediately after confirmation, arrange the two containers under diffuse sunlight or light of the same degree, and compare the state of the liquid of sample 1 with the state of the liquid of sample 2. Compare sample 1 with sample 2, and set the added amount A (g) when sample 1 begins to become more turbid or when the suspension of solid components begins to be observed as the solubility of the water-soluble resin for 100 mL of hexane at 25°C.

[0058] As water-soluble resin, for example, polyvinyl alcohol, polyvinyl pyrrolidone, water-soluble polyimides, etc. can be cited. With respect to further improving the gas barrier properties of the barrier layer and further suppressing the deactivation of the free radicals produced by the active light used in the exposure, the water-soluble resin may contain polyvinyl alcohol. Polyvinyl alcohol can be obtained by saponifying the polyvinyl acetate obtained by polymerizing vinyl acetate, for example. The saponification degree of the polyvinyl alcohol used in the present embodiment can be more than 50 mol%, more than 70 mol%, or more than 80 mol%. In addition, the upper limit of the saponification degree is 100 mol%. By containing polyvinyl alcohol having a saponification degree of more than 50 mol%, there is a tendency to further improve the gas barrier properties of the barrier layer and to further improve the resolution of the formed resist pattern. In addition, the "saponification degree" in this specification refers to the value measured according to JIS K 6726 (1994) (test method for polyvinyl alcohol) specified in Japanese Industrial Standards.

[0059] The above-mentioned polyvinyl alcohol may also be used in combination with two or more polyvinyl alcohols having different saponification degrees, viscosities, polymerization degrees, modified species, etc. The average polymerization degree of the polyvinyl alcohol may be 300 to 5000, 300 to 3500, or 300 to 2000. Furthermore, the above-mentioned water-soluble resins may be used alone or in combination of two or more. The water-soluble resin may contain, for example, polyvinyl alcohol and polyvinyl pyrrolidone. In this case, the mass ratio of polyvinyl alcohol to polyvinyl pyrrolidone (PVA:PVP) may be 40:60 to 90:10, 50:50 to 90:10, or 60:40 to 90:10.

[0060] From the perspective of improving gas barrier properties, the content of the water-soluble resin in the barrier layer-forming resin composition of the present embodiment may be 50 to 300 parts by mass, 60 to 250 parts by mass, 70 to 200 parts by mass, 80 to 150 parts by mass, or 80 to 125 parts by mass relative to 500 parts by mass of water.

[0061] (Ultraviolet light absorber)

[0062] Ultraviolet light absorbers (UV absorbers) are compounds having a light absorption band in the wavelength range of 300 nm to 400 nm. The ultraviolet light absorbers may be water-soluble. From the viewpoint of further improving the resolution, the ultraviolet light absorbers may have a maximum absorption wavelength in the wavelength range of 250 nm to 500 nm. By containing these ultraviolet light absorbers, the resolution can be improved.

[0063] The i-ray absorption rate of the ultraviolet absorber may be 5 to 95%, 10 to 90%, or 15 to 75%. The i-ray absorption rate can be measured using an ultraviolet-visible spectrophotometer.

[0064] The above-mentioned ultraviolet absorbers may be used alone or in combination of two or more. In addition, from the viewpoint of being able to suppress the aggregation and precipitation of the ultraviolet absorber in the barrier layer, the solubility in water at 20°C may be 0.01 g / 100 mL-H2O or more, 0.1 g / 100 mL-H2O or more, or 1 g / 100 mL-H2O or more.

[0065] As ultraviolet absorbers, there can be cited: oxybenzophenone compounds, triazole compounds, benzotriazole compounds, salicylate compounds, benzophenone compounds, diphenylacrylate compounds, cyanoacrylate compounds, diphenylcyanoacrylate compounds, iron or nickel complex salt compounds, etc. Among these, from the perspective of further improving the resolution, preferably oxybenzophenone compounds, benzophenone compounds, more preferably benzophenone sulfonic acid compounds, and more preferably oxybenzophenone sulfonic acid compounds. In addition, the so-called "benzophenone sulfonic acid compound" is a compound having a sulfonic group in a benzophenone compound, and the benzophenone sulfonic acid compound can be a hydrate. These compounds have a hydrophilic sulfonic group in the benzophenone skeleton, and the affinity of the benzophenone skeleton and the resist becomes higher. On the other hand, the affinity of the sulfonic group and the barrier layer becomes higher, which is inferred to enable the resolution and the removal of the barrier layer to coexist. Among the oxybenzophenone compounds, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid hydrate represented by the following formula (1) is preferred.

[0066] [Chemical formula 3]

[0067]

[0068] From the viewpoint of further improving the resolution, the content of the ultraviolet absorber in the resin composition for forming a barrier layer of the present embodiment may be 0.1 to 10.0 parts by mass, 0.3 to 7.0 parts by mass, or 0.5 to 4.0 parts by mass relative to 500 parts by mass of water. In addition, the less the content of the ultraviolet absorber, the better the resist pattern shape of the obtained resist pattern. In particular, if the content of the ultraviolet absorber is 4.0 parts by mass or less relative to 500 parts by mass of water, a resist pattern with a more excellent resist pattern shape can be formed.

[0069] From the viewpoint of making the resist pattern shape good and further improving the resolution, the content of the ultraviolet absorber in the barrier layer of the present embodiment can be more than 0 mass % and less than 10.0 mass %, 0.01-6.5 mass %, 0.01-5.0 mass %, 0.01-4.0 mass %, 0.01-2.0 mass % or 0.05-1.5 mass % based on the total amount of the barrier layer (the total amount of solid content of the barrier layer forming resin composition forming the barrier layer). And, the less the content of the ultraviolet absorber, the better the resist pattern shape of the obtained resist pattern. In particular, if the content of the ultraviolet absorber is less than 0.5 mass % based on the total amount of the barrier layer, a resist pattern with a better resist pattern shape can be formed. On the other hand, from the viewpoint of obtaining a better resolution, the content of the ultraviolet absorber can be more than 1.5 mass % or more than 1.8 mass % based on the total amount of the barrier layer.

[0070] The absorbance of the blocking layer of the present embodiment for light of wavelength 365nm can be 0.01 to 2.0, or 0.1 to 1.0. If the absorbance is 0.01 or more, there is a tendency to obtain a more excellent resolution, and if it is 2.0 or less, there is a tendency for the resist pattern shape of the obtained resist pattern to be better. The absorbance of the blocking layer can be measured, for example, using a UV spectrophotometer (manufactured by Hitachi, Ltd., spectrophotometer U-3310). The measurement is carried out as follows: a laminated film having a blocking layer of any thickness formed on a support film is placed on the measurement side, the support film is placed on the reference side, the wavelength of 300 to 700nm is continuously measured by the absorbance mode, and the value at a wavelength of 365nm is read.

[0071] (Other ingredients)

[0072] The resin composition for forming a barrier layer of the present embodiment may contain alcohols having 3 or more carbon atoms. The alcohols having 3 or more carbon atoms may be monohydric alcohols or polyhydric alcohols (excluding plasticizers of polyhydric alcohol compounds described later). The alcohols having 3 or more carbon atoms may contain at least one selected from the group consisting of compounds represented by the following chemical formulas (2) to (4) and compounds represented by the following general formula (5). By containing these alcohols having 3 or more carbon atoms, the peelability of the barrier layer and the support film can be improved. Therefore, when the support film is peeled off from the photosensitive element, the unintentional peeling of the barrier layer and the photosensitive layer can be suppressed, and the reduction in gas barrier properties and the reduction in resolution caused by the unintentional peeling can be suppressed.

[0073] [Chemical formula 4]

[0074]

[0075] [Chemical formula 5]

[0076]

[0077] [Chemical formula 6]

[0078]

[0079] [Chemical formula 7]

[0080]

[0081] In the general formula (5), R 11 represents an alkyl group, R 12 represents an alkylene group. And, R 11 The group and R 12 The sum of the carbon atoms of the groups is 3 or more. And, from the viewpoint of further improving the affinity with water,

[0082] R 11 The group and R 12 The sum of the carbon atoms of the groups may be 10 or less, 8 or less, 7 or less, or 5 or less. 11 The alkyl group represented by the formula may be an alkyl group having 1 to 4 carbon atoms, and R 12 The alkylene group represented may be an alkylene group having 1 to 3 carbon atoms. Furthermore, the alcohol having 3 or more carbon atoms represented by the general formula (5) may be 2-butoxy-ethanol or 1-methoxy-2-propanol.

[0083] The alcohols having 3 or more carbon atoms may be used alone or in combination of two or more. In addition, from the viewpoint of being able to further suppress the layer separation of the barrier layer, the solubility of the alcohols having 3 or more carbon atoms in water at 20° C. may be 300 mL / 100 mL-H2O or more, 500 mL / 100 mL-H2O or more, or 1000 mL / 100 mL-H2O or more.

[0084] The so-called "solubility of alcohols with a carbon number of 3 or more in water at 20°C" in this specification can be calculated by mixing the alcohol with water at 20°C and investigating whether there is white turbidity. Specifically, prepare sample 3 and sample 4 respectively, wherein sample 3 is obtained by placing a mixed solution of AmL of the alcohol and 100mL of water in a colorless and transparent glass container with a frosted glass stopper, and sample 4 is obtained by placing only water (100mL) in a colorless and transparent glass container with a frosted glass stopper. Next, shake and mix sample 3 and sample 4 in the glass container sufficiently, and confirm that the foam disappears. Immediately after confirmation, arrange the two containers under diffuse sunlight or light of the same degree, and compare the state of the liquid in sample 3 with the state of the liquid in sample 4. Compare sample 3 with sample 4, and set the amount of the alcohol added AmL when sample 3 is observed to be more turbid as the solubility of the alcohol in water at 20°C.

[0085] The content of the alcohol having 3 or more carbon atoms in the barrier layer forming resin composition of the present embodiment may be 100 to 500 parts by mass or 125 to 450 parts by mass relative to 500 parts by mass of water. If the content is 100 parts by mass or more, the peelability between the formed barrier layer and the support film tends to be improved, while if the content is 500 parts by mass or less, the solubility of the water-soluble resin tends to be improved, and the barrier layer tends to be easily formed.

[0086] The content of alcohols having 3 or more carbon atoms in the barrier layer of the present embodiment may be more than 0% by mass and less than 2.0% by mass, 0.001 to 2.0% by mass, or 0.005 to 1.0% by mass, based on the total amount of the barrier layer (the total amount of solid content of the barrier layer-forming resin composition forming the barrier layer). When the content is less than 2.0% by mass, there is a tendency to suppress the diffusion of alcohols in subsequent steps, and when the content is greater than 0.001% by mass, there is a tendency to improve the peelability of the barrier layer from the support film.

[0087] The resin composition for forming a barrier layer of the present embodiment may also contain alcohols having less than 3 carbon atoms. When containing alcohols having less than 3 carbon atoms, the content thereof may be 125 to 375 parts by mass or 150 to 325 parts by mass relative to 500 parts by mass of water. When the content is 125 parts by mass or more, the solubility of the water-soluble resin is improved, and the barrier layer tends to be easily formed. When the content is 375 parts by mass or less, the peelability of the formed barrier layer and the support film tends to be improved. In addition, from the viewpoint of improving the peelability of the barrier layer and the support film, the content of alcohols having less than 3 carbon atoms in the barrier layer of the present embodiment may be 0.1 to 10% by mass, based on the total amount of alcohols having more than 3 carbon atoms in the barrier layer.

[0088] Furthermore, the barrier layer-forming resin composition of the present embodiment may contain known additives such as a plasticizer and a surfactant within a range not impairing the effects of the present invention, and may contain a peeling accelerator within a range not impairing the effects of the present invention.

[0089] As a plasticizer, for example, from the viewpoint of improving elongation, a polyol compound may be contained. For example, glycerols such as glycerol, diglycerol, and triglycerol, alkylene glycols and polyalkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, and polypropylene glycol, trimethylolpropane, etc. These plasticizers may be used alone or in combination of two or more.

[0090] The resin composition for forming a barrier layer of the present embodiment can have an ultraviolet absorption rate of 5 to 95%, 10 to 90%, or 15 to 75% when it is made into a dry film with a thickness of 5 μm from the viewpoint of appropriately reducing the sensitivity of the photosensitive layer to be exposed and improving the resolution. The ultraviolet absorption rate of the dry film can be measured using an ultraviolet visible spectrophotometer.

[0091] The barrier layer in the photosensitive element of the present embodiment can be formed by, for example, applying the barrier layer-forming resin composition of the present embodiment on a support film and drying the coating.

[0092] The thickness of the barrier layer is not particularly limited. From the viewpoint of ease of removal of the barrier layer, the thickness of the barrier layer may be 12 μm or less, 10 μm or less, 8 μm or less, 7 μm or less, or 6 μm or less. Furthermore, from the viewpoint of ease of formation of the barrier layer and resolution, the thickness of the barrier layer may be 1.0 μm or more, 1.5 μm or more, 2 μm or more, 3 μm or more, or 4 μm or more. Furthermore, from the viewpoint of suppressing migration of the barrier layer, the thickness of the barrier layer may be 2 μm or more, 3 μm or more, or 4 μm or more.

[0093] From the viewpoint of appropriately reducing the sensitivity of the photosensitive layer to be exposed and improving the resolution, the ultraviolet absorption rate (UV absorption rate) of the blocking layer may be 5 to 95%, 10 to 90%, or 15 to 75%. The ultraviolet absorption rate of the blocking layer can be measured using an ultraviolet-visible spectrophotometer.

[0094] <Photosensitive layer>

[0095] The photosensitive layer of the present embodiment is a layer formed using a photosensitive resin composition described later. As long as the photosensitive resin composition is a resin composition whose properties change due to light irradiation (for example, photocuring), it can be used in combination with the desired purpose and can be negative or positive. The photosensitive resin composition may contain (A) a binder polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator. In addition, it may also contain (D) a photosensitizer, (E) a polymerization inhibitor or other components as needed. Below, the various components used in the photosensitive resin composition of the present embodiment are described in more detail.

[0096] ((A) Binder polymer)

[0097] (A) The binder polymer (hereinafter also referred to as "component (A)") can be produced, for example, by subjecting a polymerizable monomer to free radical polymerization. Examples of the polymerizable monomer include polymerizable styrene derivatives substituted at the α-position or in the aromatic ring such as styrene, vinyl toluene, and α-methylstyrene, acrylamides such as diacetone acrylamide, ethers of vinyl alcohol such as acrylonitrile and vinyl-n-butyl ether, alkyl (meth)acrylates, benzyl (meth)acrylates such as benzyl methacrylate, tetrahydrofurfuryl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate , glycidyl (meth)acrylate, 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3-tetrafluoropropyl (meth)acrylate, (meth)acrylic acid, α-bromoacrylic acid, α-chloroacrylic acid, β-furanyl (meth)acrylate, β-styryl (meth)acrylate, maleic acid, maleic anhydride, maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid monoisopropyl ester and other maleic acid monoesters, fumaric acid, cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid and propiolic acid. These can be used alone or in combination of two or more.

[0098] Among these, alkyl (meth)acrylates may be contained from the viewpoint of improving plasticity. Examples of alkyl (meth)acrylates include compounds represented by the following general formula (II) and compounds in which the alkyl groups of these compounds are substituted with hydroxyl groups, epoxy groups, halogen groups, and the like.

[0099] H2C=C(R 6 )-COOR 7 (II)

[0100] In the general formula (II), R 6 represents a hydrogen atom or a methyl group, R 7 represents an alkyl group having 1 to 12 carbon atoms. 7 Examples of the alkyl group having 1 to 12 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, and structural isomers of these groups.

[0101] Examples of the alkyl (meth)acrylate represented by the general formula (II) include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, and dodecyl (meth)acrylate. These can be used alone or in combination of two or more.

[0102] Furthermore, from the viewpoint of alkali developability, the component (A) may contain a carboxyl group. The component (A) containing a carboxyl group can be produced, for example, by subjecting a polymerizable monomer having a carboxyl group to free radical polymerization with other polymerizable monomers. The polymerizable monomer having a carboxyl group may be (meth)acrylic acid or methacrylic acid. Furthermore, the acid value of the component (A) containing a carboxyl group may be 50 to 250 mgKOH / g, 50 to 200 mgKOH / g, or 100 to 200 mgKOH / g.

[0103] From the viewpoint of improving alkali developability and alkali resistance in a good balance, the carboxyl content of component (A) (the ratio of the polymerizable monomer having a carboxyl group to the total amount of the polymerizable monomer used for the binder polymer) may be 12 to 50% by mass, 12 to 40% by mass, 15 to 35% by mass, 15 to 30% by mass, or 20 to 30% by mass. If the carboxyl content is 12% by mass or more, there is a tendency for alkali developability to be improved, and if it is 50% by mass or less, there is a tendency for excellent alkali resistance.

[0104] The content of the structural unit derived from the polymerizable monomer having a carboxyl group in the component (A) depends on the blending ratio of the polymerizable monomer having a carboxyl group and may be 12 to 50% by mass, 12 to 40% by mass, 15 to 35% by mass, 15 to 30% by mass or 20 to 30% by mass.

[0105] In addition, from the viewpoint of adhesion and chemical resistance, component (A) may use styrene or a styrene derivative as a polymerizable monomer. When the above-mentioned styrene or a styrene derivative is used as a polymerizable monomer, from the viewpoint of making adhesion and chemical resistance better, its content (the proportion of styrene or a styrene derivative relative to the total amount of polymerizable monomers used in component (A)) may be 10 to 60 mass %, 15 to 50 mass %, 30 to 50 mass %, 35 to 50 mass % or 40 to 50 mass %. If the content is 10 mass % or more, there is a tendency to improve adhesion, and if it is 60 mass % or less, there is a tendency to suppress the enlargement of the peeling piece during development and to suppress the prolonged time required for peeling.

[0106] The content of the structural unit derived from styrene or a styrene derivative in the component (A) depends on the blending ratio of the styrene or a styrene derivative and may be 10 to 60 mass %, 15 to 50 mass %, 30 to 50 mass %, 35 to 50 mass % or 40 to 50 mass %.

[0107] Furthermore, from the viewpoint of resolution and aspect ratio, benzyl (meth)acrylate may be used as a polymerizable monomer in component (A). From the viewpoint of further improving resolution and aspect ratio, the content of the structural unit derived from benzyl (meth)acrylate in component (A) may be 15 to 50% by mass, 15 to 45% by mass, 15 to 40% by mass, 15 to 35% by mass, or 20 to 30% by mass.

[0108] These binder polymers can be used alone or in combination of two or more. When two or more are used in combination, component (A) includes, for example, two or more binder polymers formed from different polymerizable monomers, two or more binder polymers with different weight average molecular weights, and two or more binder polymers with different dispersities.

[0109] (A) Component can be produced by a common method. Specifically, for example, it can be produced by radical polymerization of alkyl (meth)acrylate, (meth)acrylic acid, styrene, and the like.

[0110] From the viewpoint of improving mechanical strength and alkali developability in a good balance, the weight average molecular weight of component (A) may be 20,000 to 300,000, 40,000 to 150,000, 40,000 to 120,000, or 50,000 to 80,000. If the weight average molecular weight of component (A) is 20,000 or more, there is a tendency to be excellent in developer resistance, and if it is 300,000 or less, there is a tendency to suppress the development time from becoming longer. In addition, the weight average molecular weight in this specification is measured by gel permeation chromatography (GPC) and converted by a calibration curve prepared using standard polystyrene.

[0111] The content of the above-mentioned component (A) may be 30 to 80 parts by mass, 40 to 75 parts by mass, 50 to 70 parts by mass, or 50 to 60 parts by mass relative to 100 parts by mass of the total solid content of the component (A) and the component (B) described later. If the content of the component (A) is within this range, the coating properties of the photosensitive resin composition and the strength of the photocured portion are better.

[0112] ((B) Photopolymerizable compound)

[0113] The photosensitive resin composition according to the present embodiment may contain (B) a photopolymerizable compound (hereinafter also referred to as "component (B)"). Component (B) can be used without particular limitation as long as it is a compound capable of photopolymerization or photocrosslinking, for example, a compound having at least one ethylenically unsaturated bond in the molecule can be used.

[0114] As the (B) component, for example, compounds obtained by reacting α,β-unsaturated carboxylic acid with a polyol, bisphenol-type (meth)acrylate compounds such as bisphenol A-type (meth)acrylate compounds, carbamate monomers such as (meth)acrylate compounds having a carbamate bond, nonylphenoxyvinyloxy (meth)acrylate, nonylphenoxyoctavinyloxy (meth)acrylate, γ-chloro-β-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate, β-hydroxyethyl-β'-(meth)acryloyloxyethyl-phthalate, β-hydroxypropyl-β'-(meth)acryloyloxyethyl-phthalate, and alkyl (meth)acrylates can be used alone or in combination of two or more.

[0115] Among the above, component (B) may contain a bisphenol (meth)acrylate compound from the viewpoint of improving resolution, adhesion, and suppression of resist edge formation in a well-balanced manner. The bisphenol (meth)acrylate compound may be a compound represented by the following general formula (III).

[0116] [Chemical formula 8]

[0117]

[0118] In the general formula (III), R 1 , R 2 , R 3 and R 4 Each independently represents a hydrogen atom or a methyl group. X and Y each independently represent an ethylene group or a propylene group, and XO and YO each independently represent an oxyethylene group (hereinafter, sometimes referred to as an "EO group") or an oxypropylene group (hereinafter, sometimes referred to as a "PO group"). p1, p2, q1, and q2 each independently represent a numerical value of 0 to 40. Among them, p1+q1 and p2+q2 are both greater than 1. When X is an ethylene group and Y is a propylene group, p1+p2 is 1 to 40, and q1+q2 is 0 to 20. When X is a propylene group and Y is an ethylene group, p1+p2 is 0 to 20, and q1+q2 is 1 to 40. p1, p2, q1, and q2 represent the number of structural units of an EO group or a PO group, and therefore represent integer values ​​in a single molecule, and represent rational numbers as average values ​​in an aggregate of multiple molecules. In addition, the EO group and the PO group may exist continuously in a block manner or may exist randomly.

[0119] In the general formula (III), when X and Y are both ethylene groups, p1+p2+q1+q2 may be 1 to 20, 1 to 10, or 1 to 7 from the viewpoint of better resolution and adhesion.

[0120] Examples of the compound represented by general formula (III) include 2,2-bis(4-(meth)acryloxypolyethoxy)phenyl)propane, 2,2-bis(4-((meth)acryloxypolypropoxy)phenyl)propane, and 2,2-bis(4-((meth)acryloxypolyethoxypolypropoxy)phenyl)propane. These may be used alone or in combination of two or more.

[0121] Examples of commercially available bisphenol (meth)acrylate compounds include 2,2-bis(4-(methacryloyloxydiethoxy)phenyl)propane (“BPE-200” manufactured by Shin-Nakamura Chemical Co., Ltd.), 2,2-bis(4-(methacryloyloxypentaethoxy)phenyl)propane (“BPE-500” manufactured by Shin-Nakamura Chemical Co., Ltd. or “FA-321M” manufactured by Hitachi Chemical Co., Ltd.), 2,2-bis(4-(methacryloyloxypentadethoxy)phenyl)propane (“BPE-1300” manufactured by Shin-Nakamura Chemical Co., Ltd.), and 2,2-bis(4-(methacryloyloxypolyethoxy)phenyl)propane (“BP-2EM” manufactured by Kyoeisha Chemical Co., Ltd. (EO group: 2.6 (average value))).

[0122] From the viewpoint of further improving chemical resistance, the content of the bisphenol (meth)acrylate compound may be 1 to 50 mass %, 3 to 40 mass %, 10 to 40 mass %, 20 to 40 mass % or 30 to 40 mass % relative to the total solid content of the components (A) and (B).

[0123] Furthermore, from the viewpoint of further improving chemical resistance, the content of the bisphenol (meth)acrylate compound may be 30 to 99 mass %, 50 to 97 mass %, 60 to 95 mass %, 70 to 95 mass % or 80 to 90 mass % relative to the total solid content of the component (B).

[0124] Furthermore, from the viewpoint of achieving better resolution, the content of the compound represented by the general formula (III) in which the total number of EO groups and PO groups is 1 to 7 may be 1 to 50 mass %, 2 to 48 mass %, 3 to 45 mass %, 5 to 40 mass %, 10 to 30 mass % or 10 to 25 mass % relative to the total solid content of the components (A) and (B).

[0125] In addition, from the viewpoint of further improving the followability to the unevenness of the substrate, a compound obtained by reacting an α,β-unsaturated carboxylic acid with a polyol may also be contained. As such a compound, polyalkylene glycol di(meth)acrylate having both an EO group and a PO group in the molecule, dipentaerythritol (meth)acrylate having an EO group, and the like can be used. As a commercially available compound of dipentaerythritol (meth)acrylate having an EO group, for example, "DPEA-12" manufactured by Nippon Kayaku Co., Ltd. and the like can be cited. From the viewpoint of improving resolution, the content of dipentaerythritol (meth)acrylate having an EO group may be 1 to 10% by mass, 1.5 to 8% by mass, 2 to 8% by mass, 2.5 to 8% by mass, or 3 to 8% by mass relative to the total solid content of component (B).

[0126] In addition, in the molecule of the polyalkylene glycol di(meth)acrylate having both EO and PO groups, the EO and PO groups may exist in blocks or randomly. Furthermore, the PO group may be either an oxy-n-propylene group or an oxyisopropylene group. In addition, in the (poly)oxyisopropylene group, the secondary carbon of the propylene group may be bonded to the oxygen atom, and the primary carbon may be bonded to the oxygen atom.

[0127] As a commercially available compound of a polyalkylene glycol di(meth)acrylate having both an EO group and a PO group, for example, a polyalkylene glycol di(meth)acrylate having 6 (average) EO groups and 12 (average) PO groups ("FA-023M" and "FA-024M" manufactured by Hitachi Chemical Co., Ltd.) can be cited. In addition, from the viewpoint of improving the tracking property and resolution of the unevenness of the substrate, the content of the polyalkylene glycol di(meth)acrylate having both an EO group and a PO group can be 1 to 15 mass %, 1.5 to 15 mass %, 2 to 13 mass %, or 3 to 13 mass % relative to the total solid content of the component (B).

[0128] The content of the component (B) can be 20 to 70 parts by mass, 25 to 60 parts by mass, or 30 to 50 parts by mass relative to 100 parts by mass of the total solid content of the components (A) and (B). If the content of the component (B) is within this range, the resolution, adhesion, and resistance to the generation of resist edges of the photosensitive resin composition are improved, and the photosensitivity and coating properties are also improved.

[0129] ((C) Photopolymerization initiator)

[0130] The photosensitive resin composition according to the present embodiment may contain at least one (C) photopolymerization initiator (hereinafter also referred to as "component (C)"). The component (C) is not particularly limited as long as it can polymerize component (B), and can be appropriately selected from commonly used photopolymerization initiators.

[0131] Examples of the component (C) include aromatic ketones such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propanone-1, quinones such as alkyl anthraquinone, benzoin ether compounds such as benzoin alkyl ether, benzoin compounds such as benzoin and alkyl benzoin, benzyl derivatives such as benzyl dimethyl ketal, 2,4,5-triarylimidazole dimers such as 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer and 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, acridine derivatives such as 9-phenylacridine and 1,7-(9,9'-acridinyl)heptane, etc. These can be used alone or in combination of two or more.

[0132] Among these, from the viewpoint of improving resolution, 2,4,5-triaryl imidazole dimers may be contained. Examples of the above-mentioned 2,4,5-triaryl imidazole dimers include 2-(o-chlorophenyl)-4,5-diphenyl imidazole dimers, 2-(o-chlorophenyl)-4,5-bis-(m-methoxyphenyl) imidazole dimers, and 2-(p-methoxyphenyl)-4,5-diphenyl imidazole dimers. Among these, from the viewpoint of improving photosensitivity stability, 2-(o-chlorophenyl)-4,5-diphenyl imidazole dimers may be contained.

[0133] As a 2,4,5-triarylimidazole dimer, for example, 2,2′-bis(2-chlorophenyl)-4,4′,5,5′-tetraphenylbiimidazole is commercially available as B-CIM (product name, manufactured by Hodogaya Chemical Industry Co., Ltd.).

[0134] From the viewpoint of further improving photosensitivity and adhesion and further suppressing the light absorption of component (C), component (C) may contain at least one 2,4,5-triaryl imidazole dimer or 2-(2-chlorophenyl)-4,5-diphenyl imidazole dimer. The structure of the 2,4,5-triaryl imidazole dimer may be symmetrical or asymmetrical.

[0135] The content of component (C) may be 0.01 to 30 parts by mass, 0.1 to 10 parts by mass, 1 to 7 parts by mass, 1 to 6 parts by mass, 1 to 5 parts by mass, or 2 to 5 parts by mass relative to 100 parts by mass of the total solid content of component (A) and component (B). If the content of component (C) is 0.01 parts by mass or more, there is a tendency for improved photosensitivity, resolution, and adhesion, and if it is 30 parts by mass or less, there is a tendency for an excellent resist pattern shape.

[0136] ((D) Photosensitizer)

[0137] The photosensitive resin composition according to the present embodiment may contain (D) a photosensitizer (hereinafter also referred to as “component (D)”). By containing the component (D), there is a tendency that the absorption wavelength of active light used for exposure can be effectively utilized.

[0138] As the (D) component, for example, pyrazolines, dialkylaminobenzophenones, anthracenes, coumarins, xanthones, oxazoles, benzoxazoles, thiazoles, benzothiazoles, triazoles, distilbenes, triazines, thiophenes, naphthalimides and triarylamines can be listed. These can be used alone or in combination of two or more. From the perspective of being able to more effectively utilize the absorption wavelength of the active light used in exposure, the (D) component may contain pyrazolines, anthracenes or dialkylaminobenzophenones, and may also contain dialkylaminobenzophenones. As a commercially available compound of the dialkylaminobenzophenone class, for example, "EAB" manufactured by Hodogaya Chemical Industry Co., Ltd. can be listed.

[0139] When containing (D) component, relative to 100 parts by weight of the total solid content of (A) component and (B) component, its content can be less than 1.0 parts by weight, less than 0.5 parts by weight, less than 0.15 parts by weight, less than 0.12 parts by weight or less than 0.10 parts by weight. If relative to 100 parts by weight of the total solid content of (A) component and (B) component, the content of (D) component is less than 1.0 parts by weight, then there is a tendency to suppress the deterioration of the resist pattern shape and the resist end production, and to make the resolution better. And, from the viewpoint of easily obtaining high light sensitivity and good resolution, relative to 100 parts by weight of the total solid content of (A) component and (B) component, the content of (D) component can be more than 0.01 parts by weight.

[0140] ((E)Polymerization inhibitor)

[0141] The photosensitive resin composition according to the present embodiment may contain (E) a polymerization inhibitor (hereinafter also referred to as "component (E)"). By containing component (E), the exposure amount required for photocuring the photosensitive resin composition tends to be adjusted to the exposure amount most suitable for exposure using a projection exposure machine.

[0142] From the viewpoint of further improving the resolution, the component (E) may contain a compound represented by the following general formula (I).

[0143] [Chemical formula 9]

[0144]

[0145] In the general formula (I), R 5 represents a halogen atom, a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an amino group, an aryl group, a mercapto group, an alkyl mercapto group having 1 to 10 carbon atoms, a carboxyalkyl group having 1 to 10 carbon atoms in an alkyl group, an alkoxy group having 1 to 20 carbon atoms, or a heterocyclic group, wherein m and n are integers selected such that m is an integer greater than 2, n is an integer greater than 0, and m+n=6. When n is an integer greater than 2, R 5 They may be the same or different. In addition, the aryl group may be substituted by an alkyl group having 1 to 20 carbon atoms.

[0146] From the viewpoint of further improving the compatibility with the component (A), R 5 It may be a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. 5 The alkyl group having 1 to 20 carbon atoms represented may be an alkyl group having 1 to 4 carbon atoms. From the viewpoint of further improving the resolution, m may be 2 or 3, or may be 2.

[0147] Examples of the compound represented by the general formula (I) include catechol, resorcin, 1,4-hydroquinone, 2-methylcatechol, 3-methylcatechol, 4-methylcatechol, 2-ethylcatechol, 3-ethylcatechol, 4-ethylcatechol, 2-propylcatechol, 3-propylcatechol, 4-propylcatechol, 2-n-butylcatechol, 3-n-butylcatechol, 4-n-butylcatechol, 2-tert-butylcatechol, 3-tert-butylcatechol, 4-tert-butylcatechol, 3,5-di-tert-butylcatechol, 2-tert-butylcatechol, 3-tert-butylcatechol, 4 ... Alkyl hydroquinones such as methyl hydroquinone, ethyl hydroquinone, propyl hydroquinone, tert-butyl hydroquinone, 2,5-di-tert-butyl hydroquinone, pyrogallol, phloroglucin, etc. These can be used alone or in combination of two or more.

[0148] Among the compounds represented by the general formula (I), alkyl catechol may be used from the viewpoint of further improving the resolution.

[0149] The content of component (E) may be 0.001 to 0.3 parts by mass, 0.005 to 0.2 parts by mass, 0.01 to 0.15 parts by mass, or 0.015 to 0.1 parts by mass relative to 100 parts by mass of the total solid content of component (A) and component (B). By setting the content of component (E) to 0.3 parts by mass or less, there is a tendency that the exposure time can be shortened and the efficiency of mass production can be improved. Furthermore, by setting the content of component (E) to 0.001 parts by mass or more, there is a tendency that the photoreaction of the photocuring part can be fully carried out, and the swelling of the resist can be suppressed due to the increase in the reaction rate, and the resolution can be better. Furthermore, according to the photosensitive element of this embodiment, even if the amount of the polymerization inhibitor is not increased, the sensitivity can be appropriately reduced and the resolution can be improved, so even if the content of component (E) is set to 0.1 parts by mass or less, excellent resolution can be obtained. When the content of the component (E) is 0.1 parts by mass or less, the photosensitive layer can stably obtain appropriate sensitivity.

[0150] Furthermore, the content of the component (E) may be 0.001 to 0.3 parts by mass, 0.005 to 0.2 parts by mass, 0.01 to 0.15 parts by mass, or 0.015 to 0.1 parts by mass relative to 100 parts by mass of the solid content of the component (A). When the content of the component (E) is 0.001 parts by mass or more relative to the component (A), the thermal stability of the photosensitive resin composition tends to be improved; when the content of the component (E) is 0.3 parts by mass or less relative to the component (A), the yellowing of the photosensitive resin composition tends to be suppressed.

[0151] (Other ingredients)

[0152] In the photosensitive resin composition involved in this embodiment, with respect to 100 parts by weight of the total solid content of the components (A) and (B), 0.01 to 20 parts by weight of dyes such as malachite green, Victoria Pure Blue, brilliant green and methyl violet, photochromic agents such as tribromophenyl sulfone, leuco crystal violet, diphenylamine, benzylamine, triphenylamine, diethylaniline, o-chloroaniline and tert-butylcatechol, plasticizers such as thermochromic inhibitors and p-toluenesulfonamide, pigments, fillers, defoamers, flame retardants, adhesion-imparting agents, leveling agents, peeling accelerators, antioxidants, fragrances, developers, thermal crosslinking agents and other additives may be contained as needed. These additives may be used alone or in combination of two or more.

[0153] Furthermore, in order to improve the handling property of the photosensitive composition or adjust the viscosity and storage stability, the photosensitive resin composition involved in the present embodiment can contain at least one organic solvent as needed. As the above-mentioned organic solvent, a commonly used organic solvent can be used without particular limitation. Specifically, for example, organic solvents such as methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N,N-dimethylformamide, propylene glycol monomethyl ether, or mixed solvents thereof can be cited. These can be used alone or in combination of two or more.

[0154] <Protective layer>

[0155] The photosensitive element of this embodiment can laminate a protective layer on the surface of the photosensitive layer opposite to the surface in contact with the barrier layer. As the protective layer, for example, a polymer film such as polyethylene or polypropylene can be used. In addition, the same polymer film as the support film can be used, or a different polymer film can be used.

[0156] Hereinafter, a method for producing a photosensitive element in which a support film, a barrier layer, a photosensitive layer, and a protective layer are sequentially stacked will be described.

[0157] <Method for producing photosensitive element>

[0158] First, a water-soluble resin containing polyvinyl alcohol is slowly added to a mixed solvent of water heated to 70 to 90° C. and an organic solvent used as needed, for example, in such a manner that the solid content becomes 10 to 20% by mass, and stirred for about 1 hour, and then a UV absorber is mixed and uniformly dissolved to obtain a resin composition for forming a barrier layer containing polyvinyl alcohol and a UV absorber. In addition, in this specification, the so-called "solid content" refers to the non-volatile components of the resin composition other than the volatilizing substances such as water and organic solvents. That is, it refers to the components other than the solvents such as water and organic solvents that do not volatilize and remain in the drying process, and also includes components that are liquid, syrupy, and waxy at room temperature of about 25° C.

[0159] Next, the barrier layer-forming resin composition is coated on the support film and dried to form a barrier layer. The barrier layer-forming resin composition can be coated on the support film by a known method such as roll coating, notch wheel coating, gravure coating, air knife coating, die coating, rod coating, spray coating, etc.

[0160] Furthermore, the drying of the applied barrier layer-forming resin composition is not particularly limited as long as at least a portion of the solvent such as water can be removed, but the composition may be dried at 70 to 150° C. for 5 to 30 minutes. After drying, the amount of residual solvent in the barrier layer may be set to 2% by mass or less from the viewpoint of preventing diffusion of the solvent in subsequent steps.

[0161] Next, a photosensitive resin composition may be applied to the barrier layer of the support film on which the barrier layer is formed, and dried in the same manner as the coating of the barrier layer-forming resin composition, thereby forming a photosensitive layer on the barrier layer. Next, by laminating the protective layer on the photosensitive layer formed in this manner, a photosensitive element having a support film, a barrier layer, a photosensitive layer, and a protective layer in sequence can be manufactured. Furthermore, by laminating a support film having a barrier layer formed on the support film with a protective layer having a photosensitive layer formed on the protective layer, a photosensitive element having a support film, a barrier layer, a photosensitive layer, and a protective layer in sequence can also be obtained.

[0162] The thickness of the photosensitive layer in the photosensitive element can be appropriately selected according to the application, but in terms of the thickness after drying, it can be 1 μm or more, 5 μm or more, or 10 μm or less, 200 μm or less, 100 μm or less, 50 μm or less, or less than 20 μm. When the thickness of the photosensitive layer is 1 μm or more, 5 μm or more, or 10 μm or more, industrial coating becomes easy and productivity tends to be improved. In addition, when the thickness of the photosensitive layer is 200 μm or less, 100 μm or less, 50 μm or less, or less than 20 μm, the photosensitivity is high and the photocurability of the bottom of the resist is excellent, so there is a tendency to form a resist pattern with excellent resolution and aspect ratio.

[0163] The melt viscosity of the photosensitive layer in the photosensitive element at 110°C can be appropriately selected according to the type of substrate in contact with the photosensitive layer, but after drying, it can be 50 to 10,000 Pa·s, 100 to 5,000 Pa·s, or 200 to 1,000 Pa·s at 110°C. If the melt viscosity at 110°C is 50 Pa·s or more, there is a tendency that wrinkles and voids will not be generated in the lamination process, and productivity will be improved. In addition, if the melt viscosity at 110°C is 10,000 Pa·s or less, there is a tendency that adhesion to the substrate is improved in the lamination process, and poor adhesion is reduced.

[0164] The form of the photosensitive element involved in this embodiment is not particularly limited. For example, it can be in the form of a sheet, or it can be wound around a winding core into a roll shape. In the case of winding into a roll shape, it can be wound in a manner such that the supporting film is on the outside. As the winding core, for example, plastics such as polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin or ABS resin (acrylonitrile-butadiene-styrene copolymer) can be listed.

[0165] From the viewpoint of end face protection, an end face separator may be provided on the end face of the roll-shaped photosensitive element roll obtained in this way, and from the viewpoint of edge fusion resistance, a moisture-proof end face separator may also be provided. As a packaging method, it can be packed in a black steel sheet with low moisture permeability.

[0166] The photosensitive element according to the present embodiment can be suitably used in, for example, a resist pattern forming method and a printed wiring board manufacturing method described later.

[0167] [Method for forming resist pattern]

[0168] The method for forming a resist pattern according to the present embodiment includes: (i) using the above-mentioned photosensitive element to sequentially arrange a photosensitive layer, a barrier layer and a support film on a substrate from the substrate side (hereinafter, also referred to as "(i) photosensitive layer and barrier layer formation process"); (ii) removing the above-mentioned support film and exposing the above-mentioned photosensitive layer to active light through the above-mentioned barrier layer (hereinafter, also referred to as "(ii) exposure process"); and (iii) removing the above-mentioned barrier layer and the uncured portion of the above-mentioned photosensitive layer from the above-mentioned substrate (hereinafter, also referred to as "(iii) development process"), and other processes may also be included as needed. In addition, the so-called resist pattern can be referred to as a photocured material pattern of a photosensitive resin composition, and can also be referred to as a concave-convex pattern. In addition, depending on the purpose, the resist pattern in the present embodiment can be used as a resist, and can also be used for other purposes such as a protective film.

[0169] ((i) Photosensitive layer and barrier layer forming step)

[0170] In the photosensitive layer and barrier layer forming step, the photosensitive layer and barrier layer are formed on a substrate using the photosensitive element. The substrate is not particularly limited, and a circuit forming substrate or a die pad (lead frame substrate) such as an alloy substrate having an insulating layer and a conductor layer formed on the insulating layer can generally be used.

[0171] As a method for forming a photosensitive layer and a barrier layer on a substrate, for example, when a photosensitive element having a protective layer is used, after removing the protective layer, the photosensitive layer of the photosensitive element can be pressed onto the substrate while being heated, thereby forming a photosensitive layer and a barrier layer on the substrate. In this way, a laminate having a substrate, a photosensitive layer, a barrier layer, and a support film in this order can be obtained.

[0172] When a photosensitive element is used to form the photosensitive layer and the barrier layer, the process can be carried out under reduced pressure from the viewpoint of adhesion and followability. Heating during compression bonding can be carried out at a temperature of 70 to 130°C, and compression bonding can be carried out at 0.1 to 1.0 MPa (1 to 10 kgf / cm 2 ) under pressure, but these conditions can be appropriately selected as needed. In addition, if the photosensitive layer of the photosensitive element is heated to 70 to 130° C., there is no need to preheat the substrate in advance, but in order to further improve the adhesion and tracking properties, the substrate can also be preheated.

[0173] ((ii) Exposure process)

[0174] In the exposure process, the support film is removed, and the photosensitive layer is exposed to active light through the barrier layer. Thus, the exposed portion irradiated with active light can be photocured to form a photocured portion (latent image), and the unexposed portion not irradiated with active light can also be photocured to form a photocured portion. When the photosensitive layer and the barrier layer are formed using the above-mentioned photosensitive element, the support film present on the photosensitive layer is peeled off and then exposed. By exposing the photosensitive layer through the barrier layer, a resist pattern with excellent resolution and resist pattern shape can be formed.

[0175] As an exposure method, a known exposure method can be applied, for example, a method of irradiating active light in an image-like manner through a negative mask pattern or a positive mask pattern called an artwork (mask exposure method); LDI (Laser Direct Imaging) exposure method; or a method of using active light with an image projected with a photomask and irradiating in an image-like manner through a lens (projection exposure method), etc. Among them, from the perspective of excellent resolution, a projection exposure method can be used. That is, the photosensitive element and the like involved in this embodiment are suitable for a projection exposure method. In addition, the so-called projection exposure method can also be referred to as an exposure method using active light with attenuated energy.

[0176] As the light source of active light, there is no particular limitation as long as it is a commonly used known light source, for example, carbon arc lamp, mercury vapor arc lamp, ultra-high pressure mercury lamp, high pressure mercury lamp, xenon lamp, gas laser such as argon laser, solid laser such as YAG laser, semiconductor laser such as gallium nitride blue-violet laser, etc., which effectively radiate ultraviolet light, etc. can be used. In addition, light sources such as floodlight bulbs for photography and sun lamps that effectively radiate visible light, etc. can also be used. Among these, from the perspective of improving resolution and alignment with good balance, a light source capable of radiating i-ray monochromatic light with an exposure wavelength of 365nm, a light source capable of radiating h-ray monochromatic light with an exposure wavelength of 405nm, or a light source capable of radiating active light with an exposure wavelength of iHG mixed rays can be used, among which a light source capable of radiating i-ray monochromatic light with an exposure wavelength of 365nm can also be used. As a light source capable of radiating i-ray monochromatic light with an exposure wavelength of 365nm, for example, an ultra-high pressure mercury lamp can be cited.

[0177] ((iii) Development process)

[0178] In the development step, the barrier layer and the uncured portion of the photosensitive layer are removed from the substrate. Through the development step, a resist pattern consisting of the photocured portion formed by photocuring the photosensitive layer is formed on the substrate. When the barrier layer is water-soluble, the barrier layer can be removed by washing with water, and then the uncured portion other than the photocured portion can be removed by a developer. When the barrier layer is soluble in the developer, the barrier layer and the uncured portion other than the photocured portion can be removed together by a developer. The development method may include wet development.

[0179] In the case of wet development, a developer corresponding to the photosensitive resin composition can be used to develop by a known wet development method. Examples of wet development methods include: immersion, coating, high-pressure spray, and methods using brushing, slapping, scraping, shaking, and immersion. From the perspective of improving resolution, the most suitable is the high-pressure spray method. These wet development methods can be used alone or in combination of two or more methods.

[0180] The developer is appropriately selected according to the structure of the photosensitive resin composition, and examples thereof include alkaline aqueous solutions and organic solvent developers.

[0181] From the viewpoint of safety, stability and good operability, an alkaline aqueous solution can be used as a developer. As the alkali of the alkaline aqueous solution, for example, alkali hydroxides such as lithium, sodium or potassium hydroxides, carbonates such as lithium, sodium, potassium or ammonium carbonates or bicarbonates, alkali metal phosphates such as potassium phosphate and sodium phosphate, alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate, sodium borate, sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl-1,3-propanediol, 1,3-diamino-2-propanol and morpholine can be used.

[0182] As the alkaline aqueous solution used for development, for example, a dilute solution of 0.1 to 5% by mass of sodium carbonate, a dilute solution of 0.1 to 5% by mass of potassium carbonate, a dilute solution of 0.1 to 5% by mass of sodium hydroxide, a dilute solution of 0.1 to 5% by mass of sodium tetraborate, etc. can be used. In addition, the pH of the alkaline aqueous solution used for development can be set in the range of 9 to 11, and the temperature of the alkaline aqueous solution can be adjusted in combination with the developability of the photosensitive layer. In addition, in the alkaline aqueous solution, for example, a surfactant, a defoaming agent, a small amount of organic solvent for promoting development, etc. can be mixed. In addition, as the organic solvent used in the alkaline aqueous solution, for example, 3-acetone alcohol, acetone, ethyl acetate, alkoxyethanol having an alkoxy group with 1 to 4 carbon atoms, ethanol, isopropanol, butanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether and diethylene glycol monobutyl ether can be listed.

[0183] Examples of the organic solvent used in the organic solvent developer include 1,1,1-trichloroethane, N-methylpyrrolidone, N,N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone. From the viewpoint of preventing ignition, these organic solvents can be added with water in an amount of 1 to 20% by mass to prepare an organic solvent developer.

[0184] (Other processes)

[0185] In the resist pattern forming method according to the present embodiment, after removing the uncured portion in the developing step, heating at 60 to 250° C. or 0.2 to 10 J / cm 2 The process of further curing the resist pattern by exposing the resist pattern to an exposure amount of .

[0186] [Manufacturing method of printed wiring board]

[0187] The method for manufacturing a printed wiring board according to the present embodiment includes a process of forming a conductor pattern by etching or plating a substrate on which a resist pattern is formed by the above-mentioned method for forming a resist pattern, and may also include other processes such as a resist pattern removal process as needed. The method for manufacturing a printed wiring board according to the present embodiment can be suitably used for forming a conductor pattern by using the method for forming a resist pattern using the above-mentioned photosensitive element, and is more suitable for a method for forming a conductor pattern by plating. In addition, the conductor pattern may also be referred to as a circuit.

[0188] In the etching process, the conductive layer of the substrate not covered by the resist is etched away using a resist pattern formed on the substrate including the conductive layer as a mask, thereby forming a conductive pattern.

[0189] The etching method is appropriately selected according to the conductor layer to be removed. Examples of etching solutions include cupric chloride solution, ferric chloride solution, alkaline etching solution, and hydrogen peroxide-based etching solution. From the perspective of good etching factor, ferric chloride solution can be used.

[0190] On the other hand, in the plating process, the resist pattern formed on the substrate having the conductor layer is used as a mask to plate copper or solder etc. on the conductor layer of the substrate not covered by the resist. After the plating process, the resist is removed by removing the resist pattern described later, and then the conductor layer covered by the resist is etched to form a conductor pattern.

[0191] The plating method may be electroplating or electroless plating, and electroless plating is preferred. Examples of electroless plating include copper plating such as copper sulfate plating and copper pyrophosphate plating, solder plating such as high throw solder plating, nickel plating such as watts bath (nickel sulfate-nickel chloride) plating and nickel sulfonate plating, and gold plating such as hard gold plating and soft gold plating.

[0192] After the etching or plating treatment, the resist pattern on the substrate is removed. The resist pattern can be removed, for example, by stripping with an aqueous solution having a stronger alkalinity than the alkaline aqueous solution used in the development step. As the strongly alkaline aqueous solution, for example, a 1-10 mass % sodium hydroxide aqueous solution, a 1-10 mass % potassium hydroxide aqueous solution, etc. can be used. Among these, a 1-5 mass % sodium hydroxide aqueous solution or a potassium hydroxide aqueous solution can also be used.

[0193] Examples of a method for removing the resist pattern include a dipping method and a spraying method, and these methods may be used alone or in combination.

[0194] When the resist pattern is removed after the plating treatment, the conductor layer covered by the resist is etched by etching to form a conductor pattern, thereby manufacturing a desired printed wiring board. The etching method at this time is appropriately selected according to the conductor layer to be removed. For example, the above-mentioned etching solution can be applied.

[0195] The method for manufacturing a printed wiring board according to the present embodiment can be applied not only to the manufacture of a single-layer printed wiring board but also to the manufacture of a multilayer printed wiring board, and can also be applied to the manufacture of a printed wiring board having a small-diameter through hole or the like.

[0196] The method for manufacturing a printed wiring board according to the present embodiment can be applied to the manufacture of a high-density package substrate, in particular, the manufacture of a wiring board using a semi-additive method. Figure 2 .

[0197] Figure 2 In (a), a substrate (circuit forming substrate) is prepared in which a conductor layer 40 is formed on an insulating layer 50. The conductor layer 40 is, for example, a copper layer. Figure 2 In (b), the photosensitive layer 30 and the barrier layer 20 are formed on the conductive layer 40 of the substrate through the above-mentioned photosensitive layer and barrier layer forming steps. Figure 2 In (c), by the exposure step, the photosensitive layer 30 is irradiated with active light rays 80 on which the image of the photomask is projected through the barrier layer 20 , thereby forming a photocured portion on the photosensitive layer 30 . Figure 2In (d), a resist pattern 32 as a photocured portion is formed on the substrate by removing a region (including the barrier layer) other than the photocured portion formed in the above-mentioned exposure step from the substrate through a development step. Figure 2 In (e), a plating layer 60 is formed on the conductor layer 40 of the substrate which is not covered with the resist by a plating process using the resist pattern 32 as a photocured portion as a mask. Figure 2 In (f), after the resist pattern 32 as the photocured portion is peeled off by an aqueous solution of a strong alkali, the conductor layer 40 covered by the resist pattern 32 is removed by flash etching, thereby forming a conductor pattern 70 including the plated layer 62 after the etching process and the conductor layer 42 after the etching process. The material of the conductor layer 40 and the plated layer 60 may be the same or different. When the conductor layer 40 and the plated layer 60 are made of the same material, the conductor layer 40 and the plated layer 60 may be integrated. In addition, Figure 2 Although the projection exposure method is described in the above, the resist pattern 32 may be formed by using a mask exposure method and an LDI exposure method in combination.

[0198] As mentioned above, although the preferred embodiment of the present invention has been described, the present invention is not limited to the above-mentioned embodiment at all.

[0199] Example

[0200] Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples. In addition, "parts" and "%" are based on mass unless otherwise specified.

[0201] First, according to Synthesis Example 1, a binder polymer (A-1) was synthesized.

[0202] <Synthesis example 1>

[0203] 125 g of methacrylic acid, 25 g of methyl methacrylate, 125 g of benzyl methacrylate, and 225 g of styrene as polymerizable monomers were mixed with 1.5 g of azobisisobutyronitrile to prepare a solution a.

[0204] Furthermore, 1.2 g of azobisisobutyronitrile was dissolved in 100 g of a mixed liquid (mass ratio 3:2) of 60 g of methyl cellosolve and 40 g of toluene to prepare a solution b.

[0205] Meanwhile, 400 g of a mixed solution of methyl cellosolve and toluene at a mass ratio of 3:2 (hereinafter also referred to as "mixed solution x") was added to a flask equipped with a stirrer, a reflux cooler, a thermometer, a dropping funnel, and a nitrogen inlet tube, and the mixture was stirred and heated to 80°C while blowing nitrogen.

[0206] After 4 hours, the solution a was added dropwise to the mixed solution x in the flask at a constant dropping speed, and then stirred at 80°C for 2 hours. Next, after 10 minutes, the solution b was added dropwise to the solution in the flask at a constant dropping speed, and then the solution in the flask was stirred at 80°C for 3 hours. In addition, the solution in the flask was heated to 90°C over 30 minutes, kept at 90°C for 2 hours, and then cooled to room temperature to obtain a solution of the binder polymer (A-1). The solution of the binder polymer (A-1) was prepared in such a way that the non-volatile component (solid content) became 50% by mass after the mixed solution x was added.

[0207] The weight average molecular weight of the binder polymer (A-1) is 50,000, and the acid value is 163 mgKOH / g. In addition, the acid value is measured by neutralization titration. Specifically, it is measured in the following manner: 30 g of acetone is added to 1 g of the solution of the binder polymer, and after it is uniformly dissolved, an appropriate amount of phenolphthalein as an indicator is added to the solution of the above-mentioned binder polymer, and titrated using a 0.1N KOH aqueous solution. The weight average molecular weight is measured by utilizing gel permeation chromatography (GPC), and is derived by conversion using a calibration curve of standard polystyrene. The conditions of GPC are shown below.

[0208] -GPC conditions-

[0209] Pump: Hitachi L-6000 (manufactured by Hitachi, Ltd.)

[0210] Chromatographic columns: 3 in total (Chromatographic column specifications: 10.7mmΦ×300mm, all manufactured by Hitachi Chemical Co., Ltd.)

[0211] Gelpack GL-R420

[0212] Gelpack GL-R430

[0213] Gelpack GL-R440

[0214] Eluent: Tetrahydrofuran

[0215] Sample concentration: 120 mg of a binder polymer having a solid content of 50% by mass was taken and dissolved in 5 mL of tetrahydrofuran to prepare a sample.

[0216] Measurement temperature: 25℃

[0217] Flow rate: 2.05mL / min

[0218] Detector: Hitachi L-3300 RI (manufactured by Hitachi, Ltd., product name)

[0219] <Preparation of barrier layer-forming resin composition>

[0220] Next, each component shown in Table 1 below was mixed in the amount (unit: mass parts) shown in the table to obtain a resin composition for forming a barrier layer. Specifically, a water-soluble resin was slowly added to water and alcohols at room temperature, and heated to 90° C. after all the amounts were added. After reaching 90° C., the mixture was stirred for 1 hour and cooled to room temperature to obtain a resin composition for forming a barrier layer. In addition, the amounts other than the solvent in Table 1 are all amounts based on solid content.

[0221] <Preparation of photosensitive resin composition>

[0222] Next, each component shown in the following Table 1 was mixed in the amount (unit: part by mass) shown in the table to obtain a photosensitive resin composition.

[0223] [Table 1]

[0224]

[0225] The details of each component in Table 1 are as follows.

[0226] (Water-soluble resin)

[0227] *1: Polyvinyl alcohol PVA-205 (manufactured by Kuraray Co., Ltd., product name, saponification degree = 87 mol%)

[0228] *2: Polyvinylpyrrolidone K-30 (manufactured by Nippon Shokubai Co., Ltd., product name)

[0229] (Ultraviolet light absorber)

[0230] *3: 2-Hydroxy-4-methoxybenzophenone-5-sulfonic acid hydrate (Tokyo Chemical Industry Co., Ltd., compound represented by formula (1))

[0231] (A) Component: Binder polymer

[0232] *4: (A-1) (Binder polymer (A-1) obtained in Synthesis Example 1)

[0233] Methacrylic acid / methyl methacrylate / benzyl methacrylate / styrene = 25 / 5 / 25 / 45 (mass ratio), weight average molecular weight = 50,000, solid content = 50% by mass, methyl cellosolve / toluene = 3 / 2 (mass ratio) solution

[0234] Component (B): Photopolymerizable compound having an ethylenically unsaturated bond

[0235] *5: FA-321M (manufactured by Hitachi Chemical Co., Ltd.)

[0236] 2,2-Bis(4-(methacryloyloxypentaethoxy)phenyl)propane

[0237] *6: FA-024M (manufactured by Hitachi Chemical Co., Ltd.)

[0238] EOPO modified dimethacrylate

[0239] *7: BPE-200 (manufactured by Shin-Nakamura Chemical Industry Co., Ltd., product name)

[0240] 2,2-Bis(4-(methacryloyloxydiethoxy)phenyl)propane

[0241] Component (C): Photopolymerization initiator

[0242] *8: B-CIM (manufactured by Hodogaya Chemical Industry Co., Ltd., product name)

[0243] 2,2'-Bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbiimidazole

[0244] (D) Component: Photosensitizer

[0245] *9: EAB (manufactured by Hodogaya Chemical Industry Co., Ltd., product name)

[0246] 4,4'-Bis(diethylamino)benzophenone

[0247] (E) Component: Polymerization Inhibitor

[0248] *10: TBC (manufactured by DIC Corporation)

[0249] 4-tert-Butylcatechol

[0250] [Examples 1 to 7 and Comparative Example 1]

[0251] <Production of photosensitive elements>

[0252] As a support film of the photosensitive element, the PET films shown in Table 1 were prepared.

[0253] The details of the PET films shown in Table 1 are as follows.

[0254] FB-40: A three-layer biaxially oriented PET film having lubricant layers on the front and back surfaces (manufactured by Toray Industries, Ltd., product name, thickness: 16 μm)

[0255] (Preparation of barrier layer)

[0256] Next, the barrier layer-forming resin composition was applied onto a PET film (support film) so that the thickness became uniform, and dried for 10 minutes using a hot air convection dryer at 95° C. to form a barrier layer having a thickness of 5 μm after drying. In addition, when the density of the lubricant was different on both sides of the PET film, the barrier layer was formed on the side of the PET film where the lubricant was less.

[0257] (Production of Photosensitive Layer)

[0258] Next, the photosensitive resin composition was applied onto the barrier layer of the support film so as to have a uniform thickness, and dried for 10 minutes using a hot air convection dryer at 100° C. to form a photosensitive layer having a thickness of 15 μm after drying.

[0259] Next, a polyethylene protective film (protective layer) (manufactured by Tamapoly Co., Ltd., product name "NF-15") was laminated on the photosensitive layer to obtain a photosensitive element having a PET film (support film), a barrier layer, a photosensitive layer, and a protective layer laminated in this order.

[0260] <Production of laminate>

[0261] The copper surface of a copper-clad laminate (substrate, manufactured by Hitachi Chemical Co., Ltd., product name "MCL-E-67"), which is an epoxy glass material with copper foil having a thickness of 12 μm laminated on both sides, was treated with acid, washed with water, and then dried using an air flow. The copper-clad laminate was heated to 80°C, and while peeling off the protective layer, the above-mentioned photosensitive elements were crimped onto the copper-clad laminate in a manner that the photosensitive layer contacted the copper surface. The crimping was performed using a hot roller at 110°C, at a pressure of 0.40 MPa and a roller speed of 1.0 m / min. In this way, a laminate in which a substrate, a photosensitive layer, a barrier layer and a support film were laminated in sequence was obtained. These laminates were used as test pieces in the tests shown below. As a laminator, HLM-3000 (manufactured by Taisei-laminator Co., Ltd.) was used.

[0262] <Evaluation of photosensitivity>

[0263] A Hitachi 41-step step tablet was placed on the support film of the test piece, and a projection exposure machine (manufactured by Ushio Electric Co., Ltd., product name UX-2240SM-XJ01) with a high-pressure mercury lamp with a wavelength of 365nm was used. The photosensitive layer was exposed through the support film and the barrier layer at an exposure amount (irradiation energy) such that the number of residual steps after development of the Hitachi 41-step step tablet became 11. The light sensitivity was evaluated based on the exposure amount at this time. The smaller the exposure amount, the higher the light sensitivity.

[0264] <Resolution Evaluation>

[0265] In order to investigate the resolution, a Hitachi 41-step step exposure meter was placed on the support film of the test piece, and a glass mask pattern with a wiring pattern with a line width / space width of z / z (z=2 to 20 (varied at intervals of 1 μm)) (unit: μm) as a pattern for resolution evaluation was projected. A projection exposure machine with a high-pressure mercury lamp with a wavelength of 365nm (manufactured by Ushio Electric Co., Ltd., product name UX-2240SM-XJ01) was used. The photosensitive layer was exposed through the support film and the barrier layer with an irradiation energy of 11 levels of residual stages after development of the Hitachi 41-step step exposure meter. After exposure, the test piece was washed with water at room temperature to remove the support film and the barrier layer. Next, the photosensitive layer was spray-developed using a 1% by mass sodium carbonate aqueous solution at 30°C for a time twice the shortest development time to remove the unexposed portion. Here, the shortest development time is determined by measuring the time it takes for the unexposed portion to be completely removed by the above-mentioned development treatment. The minimum value (unit: μm) of the width of the space between the line portions (exposed portions) where the unexposed portions were completely removed by the development process was used as an index for evaluating the resolution. The smaller the value, the better the resolution. The results are shown in Table 2 below.

[0266] <Evaluation of resist pattern shape>

[0267] For the substrate evaluated in the above resolution evaluation, the cross-sectional shape of the resist pattern with a line width / space width of 10 / 10 (unit: μm) was observed using a scanning electron microscope (SEM). The cross-sectional shape of the resist pattern is shown in the following Table 2 as an evaluation of the resist pattern shape. The cross-sectional shape of the resist pattern is preferably a rectangle.

[0268] [Table 2]

[0269] Evaluation Project Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Comparative Example 1 <![CDATA[Exposure amount (ST = 11 / 41, mJ / cm 2 )]]> 150 160 180 200 230 300 500 140 Resolution(μm) 6 6 5 5 5 5 5 7 Resist pattern shape rectangle rectangle rectangle rectangle rectangle Trapezoid Trapezoid rectangle

[0270] When a high-resolution projection exposure machine was used to perform exposure under low energy conditions with the number of remaining stages becoming 11, the resolution of Examples 1 to 7 was improved compared to Comparative Example 1. In addition, it was confirmed that the amount of ultraviolet absorber added in Examples 6 to 7 was larger than that in other Examples, and the resist pattern shape was slightly deteriorated. However, the resolution of Examples 6 to 7 was good.

[0271] [Example 8]

[0272] In the composition of the resin composition for forming a barrier layer of Example 1 shown in Table 1, the amount of the ultraviolet absorber formulated was changed to 4 times (2.0 parts by mass) and the thickness of the barrier layer after drying was changed to 1 μm. In the same manner as in Example 1, a photosensitive element in which a PET film (support film), a barrier layer, a photosensitive layer and a protective layer were stacked in sequence, and a laminate in which a substrate, a photosensitive layer, a barrier layer and a support film were stacked in sequence were obtained.

[0273] The obtained laminate was evaluated for photosensitivity, resolution and resist pattern shape using the same method as in Example 1. As a result, photosensitivity and resolution equivalent to those in Example 1 were obtained, and the resist pattern shape was rectangular. However, migration of the barrier layer occurred in the formed resist pattern. More specifically, bumps and depressions were formed on the surface of the resist pattern due to migration of the barrier layer (dissolution residue of the barrier layer). Therefore, from the viewpoint of obtaining better resolution by thinning the barrier layer, it is preferred to increase the concentration of the ultraviolet absorber. However, it was found that when the barrier layer was thinned and the concentration of the ultraviolet absorber was increased, there was a problem of Figure 2 In the development step shown in (d), migration of the barrier layer (dissolution and residue of the barrier layer) tends to occur easily.

[0274] Industrial Applicability

[0275] As described above, the present invention can provide a photosensitive element, a resin composition for forming a barrier layer, a method for forming a resist pattern, and a method for producing a printed wiring board that can reduce sensitivity and improve resolution without adding a polymerization inhibitor.

[0276] Explanation of symbols

[0277] 1-photosensitive element, 2-support film, 3, 20-barrier layer, 4, 30-photosensitive layer, 5-protective layer, 32-resist pattern, 40-conductor layer, 42-conductor layer after etching, 50-insulating layer, 60-plating layer, 62-plating layer after etching, 70-conductor pattern, 80-active light.

Claims

1. A photosensitive element comprising a support film, a barrier layer and a photosensitive layer in this order, wherein the barrier layer contains a water-soluble resin and an ultraviolet absorber.

2. The photosensitive element according to claim 1, wherein The ultraviolet absorber includes a benzophenone sulfonic acid compound.

3. The photosensitive element according to claim 1 or 2, wherein The ultraviolet absorber comprises a compound represented by the following formula (1):

4. The photosensitive element according to claim 1 or 2, wherein The solubility of the ultraviolet absorber in water at 20° C. is 0.1 g / 100 mL-H 2 O or more.

5. The photosensitive element according to claim 1 or 2, wherein The content of the ultraviolet absorber in the barrier layer is more than 0 mass % and 10.0 mass % or less based on the total amount of the barrier layer.

6. The photosensitive element according to claim 1 or 2, wherein The content of the ultraviolet absorber in the barrier layer is 1.5% by mass or more based on the total amount of the barrier layer.

7. The photosensitive element according to claim 1 or 2, wherein The ultraviolet absorption rate of the barrier layer is 5 to 95%.

8. The photosensitive element according to claim 1 or 2, wherein The water-soluble resin includes polyvinyl alcohol.

9. The photosensitive element according to claim 8, wherein The polyvinyl alcohol has a saponification degree of 80 mol % or more.

10. The photosensitive element according to claim 1 or 2, wherein The water-soluble resin includes polyvinyl pyrrolidone.

11. The photosensitive element according to claim 1 or 2, wherein The water-soluble resin comprises polyvinyl alcohol and polyvinyl pyrrolidone, The mass ratio of the polyvinyl alcohol to the polyvinyl pyrrolidone (PVA:PVP) is 60:40 to 90:

10.

12. The photosensitive element according to claim 1 or 2, wherein The barrier layer contains an alcohol having 3 or more carbon atoms.

13. The photosensitive element according to claim 12, wherein The content of the alcohol having 3 or more carbon atoms in the barrier layer is more than 0 mass % and 2.0 mass % or less based on the total amount of the barrier layer.

14. The photosensitive element according to claim 1 or 2, wherein The photosensitive layer is a layer formed using a photosensitive resin composition containing (A) a binder polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator.

15. The photosensitive element according to claim 14, wherein The photosensitive resin composition contains (D) a photosensitizer, The content of the (D) photosensitizer in the photosensitive resin composition is 0.01 parts by mass or more based on 100 parts by mass of the total solid content of the (A) binder polymer and the (B) photopolymerizable compound.

16. The photosensitive element according to claim 14, wherein The photosensitive resin composition contains (E) a polymerization inhibitor, The content of the (E) polymerization inhibitor in the photosensitive resin composition is 0.1 parts by mass or less based on 100 parts by mass of the total solid content of the (A) binder polymer and the (B) photopolymerizable compound.

17. The photosensitive element according to claim 1 or 2, wherein The supporting film is a polyester film.

18. The photosensitive element according to claim 1 or 2, wherein The thickness of the barrier layer is 2-12 μm.

19. A method for forming a resist pattern, comprising: Using the photosensitive element according to any one of claims 1 to 18, a step of sequentially disposing a photosensitive layer, a barrier layer, and a support film on a substrate from the substrate side; The supporting film is removed, and the photosensitive layer is exposed to light through the barrier layer by using active light; as well as The step of removing the uncured portion of the photosensitive layer and the barrier layer from the substrate.

20. A method for manufacturing a printed circuit board, comprising: A step of forming a conductor pattern by etching or plating the substrate on which the resist pattern is formed by the resist pattern forming method according to claim 19.

Images