CN107924130B

CN107924130B - Photosensitive element, resin composition for forming barrier layer, method for forming resist pattern, and method for producing printed wiring board

Info

Publication number: CN107924130B
Application number: CN201680044650.3A
Authority: CN
Inventors: 粂壮和; 小野博史; 松村辽
Original assignee: Showa Denko KK
Current assignee: Lishennoco Co ltd
Priority date: 2015-07-30
Filing date: 2016-07-20
Publication date: 2022-01-14
Anticipated expiration: 2036-07-20
Also published as: KR20230129587A; KR102572426B1; CN110161802B; CN110161802A; JPWO2017018299A1; TW201710796A; JP6870612B2; CN107924130A; WO2017018299A1; CN110225665B; KR20180035827A; CN110225665A; TWI705307B; MY196431A

Abstract

The invention aims to provide a photosensitive element, which can improve the stripping property of a barrier layer and a support film without using a stripping accelerator; a photosensitive element is provided, which comprises a support film, a barrier layer and a photosensitive layer in this order, wherein the barrier layer contains a water-soluble resin and an alcohol having 3 or more carbon atoms.

Description

Photosensitive element, resin composition for forming barrier layer, method for forming resist pattern, and method for producing printed wiring board

Technical Field

The present disclosure relates to 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.

Background

Conventionally, in the field of manufacturing printed wiring boards, photosensitive resin compositions and photosensitive elements having a layer formed using a photosensitive resin composition (hereinafter, also referred to as a "photosensitive layer") on a support film have been widely used as resist materials for etching, plating, and the like.

The printed wiring board is manufactured by, for example, the following steps using the photosensitive element. That is, first, the photosensitive layer of the photosensitive element is laminated on a circuit-forming substrate such as a copper-clad laminate. In this case, the photosensitive layer is laminated so that the surface opposite to the surface in contact with the support film is in close contact with the surface of the circuit-forming substrate on which the circuit is formed. The lamination is performed, for example, by heat-pressing the photosensitive layer onto the circuit-forming substrate (normal pressure lamination method).

Next, a desired region of the photosensitive layer is exposed through the support film using a mask film or the like, thereby generating radicals. The generated radicals contribute to a crosslinking reaction (photocuring reaction) of the photopolymerizable compound through several reaction paths. Next, the support film is peeled off, and then uncured portions of the photosensitive layer are dissolved or dispersed and removed by a developing solution, thereby forming a resist pattern. Next, a conductor pattern is formed by performing etching treatment or plating treatment using the resist pattern as a resist, and finally, the photo-cured portion (resist pattern) of the photosensitive layer is peeled off (removed).

In recent years, a method of forming an excellent resist pattern by exposing a photosensitive layer to light after peeling off a support film before exposure has been studied. However, when the photosensitive layer is exposed after the support film is peeled off, the generated radicals come into contact with oxygen in the air, and the radicals are rapidly stabilized (inactivated), so that the photocuring reaction of the photopolymerizable compound is difficult to progress. In order to reduce the effect of oxygen contamination during exposure by peeling off the support film, this method has been studied on using a photosensitive element having a barrier layer (barrier layer) having gas barrier properties between the support film and the photosensitive layer (see, for example, patent documents 1 to 3).

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 5483734

Patent document 2: japanese patent laid-open publication No. 2013-24913

Patent document 3: japanese patent No. 5551255

Disclosure of Invention

Problems to be solved by the invention

In the photosensitive elements having the barrier layer containing a water-soluble resin as described in patent documents 1 to 3, the adhesion between the barrier layer and the support film may be strong because the affinity between the water-soluble resin and the support film is high. In this case, when the support film is peeled from the barrier layer of the photosensitive element, it becomes difficult to peel the support film, and the barrier layer or the photosensitive layer may be broken.

Heretofore, it has been proposed to improve the releasability between a barrier layer and a support film by adding a release promoter such as silicone or a fluorine-based surfactant to a resin composition for forming a barrier layer containing a water-soluble resin to reduce the adhesive property between the barrier layer and the support film.

However, the following problems are known to exist: the addition of such a peeling accelerator such as a surfactant makes the formed barrier layer more likely to be cloudy. Further, since a release promoter such as a surfactant is present at the interface between the barrier layer and the support film, there is a problem that the interface composition fluctuates or the adhesiveness between the barrier layer and the support film changes in the long term view, and it is difficult to maintain stable support film releasability (releasability between the barrier layer and the support film).

The present disclosure has been made in view of the problems of the prior art, and an object thereof is to provide 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 improve the releasability between the barrier layer and a support film without using a release promoter.

Means for solving the problems

In order to achieve the above object, the present disclosure provides 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 alcohol having 3 or more carbon atoms.

The photosensitive element of the present disclosure can improve the releasability between the barrier layer and the support film without using a release promoter by including an alcohol having 3 or more carbon atoms in the barrier layer. According to such a photosensitive element, the support film can be smoothly peeled off from the barrier layer, and hence defects in the barrier layer and the photosensitive layer can be suppressed. Further, since the peelability of the barrier layer and the support film can be improved without using a peeling accelerator, the generation of turbidity of the barrier layer and the temporal change in peelability of the support film due to the presence of the peeling accelerator can be suppressed. Therefore, it can be said that a resist pattern having excellent resolution and resist pattern shape can be formed by using the photosensitive element of the present disclosure.

In the photosensitive element of the present disclosure, the alcohol having 3 or more carbon atoms may contain at least one of the group consisting of compounds represented by the following chemical formulas (1) to (3) and compounds represented by the following general formula (4). According to such a photosensitive element, the releasability between the barrier layer and the support film can be further improved.

[ solution 1]

[ solution 2]

[ solution 3]

[ solution 4]

[ in the general formula (4), R¹¹Represents an alkyl group, R¹²Represents an alkylene group, R¹¹And R¹²The sum of the carbon numbers of the groups of (a) is greater than or equal to 3.]

In the photosensitive element of the present disclosure, the solubility of the alcohol having 3 or more carbon atoms in water at 20 ℃ may be 300mL or more per 100mL of water. According to such a photosensitive element, layer separation of the barrier layer can be further suppressed, and a photosensitive element excellent in practical use can be provided.

In the photosensitive element of the present disclosure, the content of the alcohol having 3 or more carbon atoms in the barrier layer may be more than 0% by mass and 2.0% by mass or less based on the total amount of the barrier layer. According to such a photosensitive element, diffusion of alcohols in the subsequent step can be suppressed.

In the photosensitive element of the present disclosure, the water-soluble resin may contain polyvinyl alcohol. According to such a photosensitive element, the gas barrier property of the barrier layer can be further improved, and deactivation of radicals generated by active light used for exposure can be further suppressed.

In the photosensitive element of the present disclosure, the support film may be a polyester film. According to such a 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.

The present disclosure also provides a resin composition for forming a barrier layer, which contains a water-soluble resin, an alcohol having 3 or more carbon atoms, and water. According to such a resin composition for forming a barrier layer, a barrier layer having excellent releasability from a support film can be formed without using a release promoter.

In the resin composition for forming a barrier layer of the present disclosure, the alcohol having 3 or more carbon atoms may contain at least one of the group consisting of compounds represented by the chemical formulas (1) to (3) and compounds represented by the general formula (4). According to such a resin composition for forming a barrier layer, a barrier layer having more excellent releasability from a support film can be formed.

In the resin composition for forming a barrier layer of the present disclosure, the solubility of the alcohol having a carbon number of 3 or more in water at 20 ℃ may be 300mL or more per 100mL of water. Such a barrier layer-forming resin composition can form a barrier layer in which layer separation is suppressed.

In the resin composition for forming a barrier layer of the present disclosure, the content of the alcohol having 3 or more carbon atoms may be 100 to 500 parts by mass with respect to 500 parts by mass of water. According to such a resin composition for forming a barrier layer, a barrier layer having more excellent releasability from a support film can be formed, and the barrier layer can be easily formed because the solubility of the water-soluble resin is improved.

In the barrier layer-forming resin composition of the present disclosure, the water-soluble resin may contain polyvinyl alcohol. The barrier layer-forming resin composition can form a barrier layer having further excellent gas barrier properties.

Further, the present disclosure provides a method of forming a resist pattern, including: a step of disposing a photosensitive layer, a barrier layer and a support film on a substrate in this order from the substrate side using the photosensitive element of the present disclosure; removing the support film and exposing the photosensitive layer with active light through the barrier layer; and removing the uncured portion of the photosensitive layer and the barrier layer from the substrate. According to such a method for forming a resist pattern, since a resist pattern is formed using the photosensitive element of the present disclosure, a resist pattern having excellent resolution and resist pattern shape can be formed.

The present disclosure further provides a method for manufacturing a printed wiring board, including: and a step of forming a conductor pattern by performing etching treatment or plating treatment on the substrate on which the resist pattern is formed by the resist pattern forming method of the present disclosure. According to such a method for manufacturing a printed wiring board, since a resist pattern is formed by the method for forming a resist pattern of the present disclosure, a resist pattern having excellent resolution and resist pattern shape can be formed, and a method for manufacturing a printed wiring board suitable for increasing the density of a printed wiring board can be provided.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present disclosure, 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 can be provided, which can improve the peelability of the barrier layer from a support film without using a peeling accelerator.

Drawings

Fig. 1 is a schematic cross-sectional view showing one embodiment of a photosensitive element of the present disclosure.

Fig. 2 is a diagram schematically showing an example of a process for manufacturing a printed wiring board by the semi-additive method.

Detailed Description

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings as necessary. In the following embodiments, it is needless to say that the constituent elements (including the element steps) are not essential unless otherwise explicitly indicated or clearly considered essential in principle. This is also true for numerical values and ranges, which should not be construed as unduly limiting the disclosure.

In the present specification, the term "meth (acrylic acid)" means at least one of acrylic acid and methacrylic acid corresponding thereto. The same applies to other similar expressions such as (meth) acrylate.

In the present specification, the term "step" is not limited to an independent step, and is also included in the term as long as the intended function of the step can be achieved even when the step cannot be clearly distinguished from other steps.

In the present specification, the numerical range expressed by "to" means a range including numerical values before and after "to" as the minimum value and the maximum value, respectively. In the numerical ranges recited in the present specification, the upper limit or the lower limit of the numerical range in one stage may be replaced with the upper limit or the lower limit of the numerical range in another stage. In addition, in the numerical ranges described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the values shown in the examples. In the present specification, the term "layer" includes a structure having a shape formed entirely when viewed in a plan view, and also includes a structure having a shape formed partially.

[ photosensitive element ]

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 this order, and may further include another layer such as a protective layer 5. The barrier layer contains a water-soluble resin and an alcohol having 3 or more carbon atoms. By using the photosensitive element of the present embodiment, the releasability between the barrier layer and the support film can be improved. Further, the photosensitive element of the present embodiment can suppress layer separation of the barrier layer, and thus is an excellent element in practical use. Each layer in the photosensitive element according to the present embodiment will be described in detail below.

< supporting film >

The support film of the present embodiment can be used without particular limitation. Examples thereof include: polyester films such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and polyethylene 2, 6-naphthalate (PEN), and polyolefin films such as polypropylene and polyethylene. Among them, a polyester film may be used. By using a polyester film as the support film, the mechanical strength and heat resistance of the support film tend to be improved. Further, by using the polyester film, it is possible to suppress defects such as wrinkles of the barrier layer generated when the barrier layer is formed on the support film, and it is possible to improve workability. In addition, a polyester film containing particles (lubricant or the like) may be used from the viewpoint of suppressing the occurrence of minute peeling of the resist pattern. In the case of using a polyester film containing particles (lubricant, etc.), a barrier layer may be formed on the surface having the particles (lubricant, etc.). Examples of the polyester film include a polyester film containing particles (such as a lubricant), a polyester film having layers containing particles (such as a lubricant) formed on both surfaces thereof, and a polyester film having layers containing particles (such as a lubricant) formed on one surface thereof. The support film may be a single layer or a multilayer.

Examples of the method of adding particles such as a lubricant to the support film include the following methods: a method of incorporating particles (lubricant, etc.) in the support film; a method of forming a layer containing particles (lubricant or the like) on a support film by using a known method such as roll coating, flow coating, spray coating, curtain coating, dip coating, slot die coating, or the like.

The haze of the support film can be 0.01-5.0%, 0.01-1.5%, 0.01-1.0%, or 0.01-0.5%. When the haze is 0.01% or more, the support film itself tends to be easily produced, and when the haze is 5.0% or less, foreign matter in the photosensitive layer tends to be easily detected when the photosensitive layer of the photosensitive element is formed. Herein, "haze" refers to turbidity. The haze in the present disclosure is a value measured by a commercially available turbidimeter (turbidimeter) according to the method defined in JIS K7105. The haze can be measured by a commercially available haze meter such as NDH-5000 (trade name, manufactured by Nippon Denshoku industries Co., Ltd.).

The support film may be obtained from commercially available general industrial films and used as a support film for a photosensitive element by appropriate processing. Specifically, examples of the PET film include "FB-40" (product name manufactured by tokyo corporation), "a 4100", "a 1517" (product name manufactured by tokyo florists corporation), "G2H" (product name manufactured by dupont membrane corporation), and the like.

The thickness of the support film may be 1-200 μm, 1-100 μm, 1-60 μm, 5-60 μm, 10-50 μm, 10-40 μm, 10-30 μm, or 10-25 μm. The support film can be prevented from breaking when the support film is peeled off by having a thickness of 1 μm or more. Further, since the thickness of the support film is 200 μm or less, economic benefits tend to be easily obtained.

< Barrier layer >

The photosensitive element of the present embodiment includes a barrier layer between the support film and the photosensitive layer. The barrier layer contains a water-soluble resin and an alcohol having 3 or more carbon atoms. According to the photosensitive element of the present embodiment, since the support film can be smoothly peeled from the barrier layer even when the barrier layer does not contain a peeling accelerator, deterioration in resolution of a resist pattern to be formed can be suppressed when the photosensitive layer is exposed through the barrier layer after the support film is peeled. The barrier layer may be formed using a resin composition for forming a barrier layer of the present embodiment described later, and the resin composition for forming a barrier layer of the present embodiment contains a water-soluble resin, an alcohol having 3 or more carbon atoms, and water. The barrier layer may have water solubility or solubility in a developer. In view of further improving the gas barrier properties of the barrier layer, the adhesion between the support film and the barrier layer may be smaller than the adhesion between the barrier layer and the photosensitive layer. That is, it can be said that unintentional separation of the barrier layer and the photosensitive layer is suppressed when the support film is separated from the photosensitive element.

(Water-soluble resin)

Here, the "water-soluble resin" means a resin having a solubility of 5g or less in 100mL of hexane at 25 ℃. The solubility can be calculated by mixing hexane at 25 ℃ with the dried water-soluble resin and examining the presence or absence of white turbidity. Specifically, the following are prepared: sample 1 obtained by placing a mixture of dried water-soluble resin A (g) and hexane (100mL-A) and sample 2 obtained by placing 100mL of hexane alone in a colorless and transparent glass container with a frosted glass stopper. Then, the sample in the glass container was sufficiently shaken and mixed to confirm that the foam was disappeared. Immediately after the confirmation, the two containers were arranged under the diffused sunlight or the same light, and the liquid state of sample 1 and the liquid state of sample 2 were compared. When sample 1 and sample 2 were compared, the amount of addition A (g) at which the turbidity of sample 1 started to be observed or the floating of the solid content started to be observed was defined as the solubility of the water-soluble resin in 100mL of hexane at 25 ℃.

Examples of the water-soluble resin include polyvinyl alcohol, polyvinyl pyrrolidone, and water-soluble polyimides. The water-soluble resin may contain polyvinyl alcohol from the viewpoint of further improving the gas barrier property of the barrier layer and further suppressing the deactivation of radicals generated by the active light used for exposure. Polyvinyl alcohol can be obtained by, for example, saponifying polyvinyl acetate obtained by polymerizing vinyl acetate. The saponification degree of the polyvinyl alcohol used in the present embodiment may be 50 mol% or more, 70 mol% or more, or 80 mol% or more. The upper limit of the saponification degree is 100 mol%. By including polyvinyl alcohol having a saponification degree of 50 mol% or more, the gas barrier property of the barrier layer can be further improved, and the resolution of the formed resist pattern tends to be further improved. The "degree of saponification" in the present specification means a value measured in accordance with JIS K6726(1994) (test method for polyvinyl alcohol) prescribed in japanese industrial standards.

Two or more kinds of polyvinyl alcohols having different degrees of saponification, viscosity, polymerization degree, modification species, and the like may be used in combination. The polyvinyl alcohol may have an average degree of polymerization of 300 to 5000, 300 to 3500, or 300 to 2000. The water-soluble resin may be used singly or in combination of two or more. The water-soluble resin may also contain, for example, polyvinyl alcohol and polyvinyl pyrrolidone. In this case, the mass ratio of polyvinyl alcohol to polyvinylpyrrolidone (PVA: PVP) may be 40:60 to 90:10, 50:50 to 90:10, or 60:40 to 90: 10.

The water-soluble resin content in the resin composition for forming a barrier layer 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 with respect to 500 parts by mass of water, from the viewpoint of improving the gas barrier property.

(alcohols having 3 or more carbon atoms)

The alcohol having 3 or more carbon atoms may be a monohydric alcohol or a polyhydric alcohol (except for a plasticizer of a polyhydric alcohol compound described later). The number of carbons of an alcohol having a carbon number of 3 or more means the sum of the carbon numbers of the alcohols, and may be 10 or less, 8 or less, 7 or less, 6 or less, or 5 or less. The alcohol having 3 or more carbon atoms may contain at least one selected from the group consisting of compounds represented by the following chemical formulas (1) to (3) and compounds represented by the following general formula (4). By containing these alcohols having 3 or more carbon atoms, the releasability between the barrier layer and the support film can be further improved.

[ solution 5]

[ solution 6]

[ solution 7]

[ solution 8]

In the general formula (4), R¹¹Represents an alkyl group, R¹²Represents an alkylene group. Furthermore, R¹¹And R¹²The sum of the carbon numbers of the groups of (a) is greater than or equal to 3. In addition, from the viewpoint of further improving the affinity with water, R¹¹And R¹²The sum of the carbon numbers of the groups (a) may be less than or equal to 10, less than or equal to 8, less than or equal to 7, less than or equal to 6, or less than or equal to 5. R¹¹The alkyl group may be C1-4 alkyl group, R¹²The alkylene group represented by the formula (I) may be an alkylene group having 1 to 3 carbon atoms. In addition, R is¹¹Alkyl and R¹²Each of the alkylene groups may have a substituent or may have no substituent. In the case of having a substituent, R¹¹The number of carbons of the group(s) and R¹²The carbon number of the group (b) includes the carbon number of the substituent. The alcohol having 3 or more carbon atoms represented by the general formula (4) may be 2-butoxy-ethanol or 1-methoxy-2-propanol.

The alcohols having a carbon number of 3 or more may be used singly or in combination of two or more. Further, from the viewpoint of being able to more suppress layer separation of the barrier layer, the solubility of the alcohol having a carbon number of 3 or more with respect to water at 20 ℃ may be 300mL or more/100 mL of water, 500mL or more/100 mL of water, or 1000mL or more/100 mL of water.

The "solubility of an alcohol having 3 or more carbon atoms in water at 20 ℃" in the present specification can be calculated by mixing the alcohol with water at 20 ℃ and examining the presence or absence of white turbidity. Specifically, the following are prepared: into a colorless and transparent glass container with a ground glass stopper, sample 3 obtained by adding a mixed solution of the alcohol AmL and water (100-a) mL and sample 4 obtained by adding only water (100mL) were put. Next, after sufficiently shaking and mixing the sample 3 and the sample 4 in the glass container, respectively, it was confirmed that the foam was lost. Immediately after the confirmation, the two containers were arranged under the diffused sunlight or the same light, and the state of the liquid in the sample 3 and the state of the liquid in the sample 4 were compared. The amount of the alcohol added, AmL, when the sample 3 was observed to be more turbid was compared with the sample 4, and the solubility of the alcohol in water at 20 ℃ was defined as the amount of the alcohol added.

The content of the alcohol having 3 or more carbon atoms in the resin composition for forming a barrier layer of the present embodiment may be 100 to 500 parts by mass, 110 to 480 parts by mass, 120 to 460 parts by mass, 125 to 440 parts by mass, 125 to 420 parts by mass, or 125 to 400 parts by mass with respect to 500 parts by mass of water. If the content is 100 parts by mass or more, the releasability between the formed barrier layer and the support film tends to be improved, and 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.

The content of the alcohol having 3 or more carbon atoms in the barrier layer of the present embodiment may be more than 0 mass% and 2.0 mass%, 0.001 to 2.0 mass%, or 0.005 to 1.0 mass% based on the total amount of the barrier layer (the total amount of solid components of the barrier layer-forming resin composition forming the barrier layer). When the content is less than or equal to 2.0 mass%, alcohol diffusion in the subsequent step tends to be suppressed, when the content exceeds 0 mass%, the releasability between the barrier layer and the support film tends to be improved, and when the content is greater than or equal to 0.001 mass%, the releasability between the barrier layer and the support film tends to be further improved.

The resin composition for forming a barrier layer of the present embodiment may contain an alcohol having less than 3 carbon atoms. When alcohols having a carbon number of less than 3 are contained, the content thereof may be 125 to 375 parts by mass or 150 to 325 parts by mass with respect to 500 parts by mass of water. When the content is 125 parts by mass or more, the solubility of the water-soluble resin tends to be improved and the barrier layer tends to be formed easily, and when the content is 375 parts by mass or less, the releasability between 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 the alcohol having a carbon number of less than 3 in the barrier layer in the present embodiment may be 0.1 to 10 mass% based on the total amount of the alcohols in the barrier layer, or 0.1 to 10 mass parts based on 100 mass parts of the total amount of the alcohol having a carbon number of 3 or more in the barrier layer.

The resin composition for forming a barrier layer according to the present embodiment may contain known additives such as a plasticizer and a surfactant in a range that does not impair the effects of the present disclosure. In addition, a peeling accelerator may be contained within a range not to impair the effects of the present disclosure.

The plasticizer may contain a polyol compound, for example, from the viewpoint of improving the extensibility. Examples thereof include glycerin such as glycerin, diglycerin and triglycerin; (poly) alkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, and polypropylene glycol; trimethylolpropane, and the like. These plasticizers may be used singly or in combination of two or more.

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

The thickness of the barrier layer is not particularly limited. 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 from the viewpoint of easy removal of the barrier layer. Further, 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 from the viewpoint of easy formation of the barrier layer and resolution.

The barrier layer in the present embodiment may have photosensitivity, but the photosensitivity is lower than that of the photosensitive layer. Further, the barrier layer may not have photosensitivity. When the blocking layer does not have photosensitivity, the sensitivity stability of the photosensitive layer tends to be further improved. The term "photosensitive" means that a resist pattern can be formed, for example, when the photosensitive layer is exposed, and if necessary, subjected to a post-exposure heat treatment, and then developed using a developer for removing uncured portions of the photosensitive layer.

< photosensitive layer >

The photosensitive layer of the present embodiment is a layer formed using a photosensitive resin composition described later. The photosensitive resin composition may be a negative type or a positive type depending on the intended purpose as long as the property thereof is changed by light irradiation (for example, photocuring). The photosensitive resin composition may contain (a) a binder polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator. Further, if necessary, (D) a photosensitizer, (E) a polymerization inhibitor or other components may be contained. Hereinafter, each component used in the photosensitive resin composition of the present embodiment will be described in more detail.

((A) adhesive Polymer)

(A) The binder polymer (hereinafter, also referred to as "component (a)") can be produced, for example, by radical polymerization of a polymerizable monomer. Examples of the polymerizable monomer include: polymerizable styrene derivatives substituted with an α -position or an aromatic ring, such as styrene, vinyltoluene, and α -methylstyrene; acrylamides such as diacetone acrylamide; acrylonitrile; vinyl alcohol ethers such as vinyl-n-butyl ether; alkyl (meth) acrylates; benzyl (meth) acrylate 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, alpha-bromoacrylic acid, alpha-chloroacrylic acid, beta-furanyl (meth) acrylic acid, beta-styryl (meth) acrylic acid, maleic anhydride; maleic acid monoesters such as monomethyl maleate, monoethyl maleate, and monoisopropyl maleate; fumaric acid, cinnamic acid, alpha-cyanocinnamic acid, itaconic acid, crotonic acid, and propiolic acid. These may be used singly or in combination of two or more.

Among them, alkyl (meth) acrylates may be contained from the viewpoint of improvement of moldability. Examples of the alkyl (meth) acrylate include: compounds represented by the following general formula (II), and compounds obtained by substituting alkyl groups of these compounds with hydroxyl groups, epoxy groups, halogen groups, or the like.

H₂C＝C(R⁶)-COOR⁷ (II)

In the general formula (II), R⁶Represents a hydrogen atom or a methyl group, R⁷Represents an alkyl group having 1 to 12 carbon atoms. As R⁷Examples 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.

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, dodecyl (meth) acrylate, and the like. These may be used singly or in combination of two or more.

In addition, the component (a) may contain a carboxyl group from the viewpoint of alkali developability. The component (a) containing a carboxyl group can be produced, for example, by radical polymerization of a polymerizable monomer having a carboxyl group and another polymerizable monomer. The polymerizable monomer having a carboxyl group may be (meth) acrylic acid or methacrylic acid. The component (A) having a carboxyl group may have an acid value of 50 to 250mgKOH/g, 50 to 200mgKOH/g, or 100 to 200 mgKOH/g.

The carboxyl group content (the ratio of the polymerizable monomer having a carboxyl group to the total amount of the polymerizable monomers used in the binder polymer) of the component (a) may be 12 to 50 mass%, 12 to 40 mass%, 15 to 35 mass%, 15 to 30 mass%, or 20 to 30 mass%, from the viewpoint of improving the alkali developability and alkali resistance in a well-balanced manner. When the carboxyl group content is 12% by mass or more, the alkali developability tends to be improved, and when the carboxyl group content is 50% by mass or less, the alkali resistance tends to be excellent.

The content of the structural unit derived from the polymerizable monomer having a carboxyl group in the component (A) may be 12 to 50 mass%, 12 to 40 mass%, 15 to 35 mass%, 15 to 30 mass%, or 20 to 30 mass% in relation to the content of the polymerizable monomer having a carboxyl group.

In addition, from the viewpoint of adhesion and chemical resistance, styrene or a styrene derivative may be used as the component (a) as a polymerizable monomer. When the styrene or styrene derivative is used as the polymerizable monomer, the content thereof (the blending ratio of the styrene or styrene derivative to the total amount of the polymerizable monomers used as the 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%, from the viewpoint of improving the adhesion and chemical resistance. When the content is 10% by mass or more, the adhesiveness tends to be improved, and when the content is 60% by mass or less, the peeling sheet tends to be prevented from becoming large during development, and the time required for peeling tends to be shortened.

The content of the structural unit derived from styrene or a styrene derivative in the 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% in relation to the content of the styrene or the styrene derivative.

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

These binder polymers may be used singly or in combination of two or more. When two or more components (a) are used in combination, examples thereof include: two or more binder polymers formed from different polymerizable monomers, two or more binder polymers having different weight average molecular weights, and two or more binder polymers having different degrees of dispersion.

(A) The component (b) can be produced by a conventional method. Specifically, for example, the acrylic resin composition can be produced by radical polymerization of an alkyl (meth) acrylate, a (meth) acrylic acid, styrene, and the like.

The weight average molecular weight of the 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, from the viewpoint of improving the mechanical strength and the alkali developability in a well-balanced manner. When the weight average molecular weight of the component (a) is 20,000 or more, the developing solution resistance tends to be excellent, and when it is 300,000 or less, the developing time tends to be suppressed from increasing. The weight average molecular weight in the present specification is a value obtained by measuring the weight average molecular weight by Gel Permeation Chromatography (GPC) and converting the weight average molecular weight by a calibration curve prepared using standard polystyrene.

The content of the 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 based on 100 parts by mass of the total solid content of the component (A) and the component (B) described later. When the content of the component (A) is within this range, the coating property of the photosensitive resin composition and the strength of the photocured portion become more favorable.

((B) photopolymerizable Compound)

The photosensitive resin composition according to the present embodiment may contain (B) a photopolymerizable compound (hereinafter, also referred to as "component (B)"). (B) The component (b) is not particularly limited as long as it is a compound capable of photopolymerization or a compound capable of photocrosslinking, and for example, a compound having at least one ethylenically unsaturated bond in the molecule can be used.

Examples of the component (B) include: a compound obtained by reacting a polyhydric alcohol with an α, β -unsaturated carboxylic acid, a bisphenol-type (meth) acrylate compound such as a bisphenol a-type (meth) acrylate compound, a urethane monomer such as a (meth) acrylate compound having a urethane bond, nonylphenoxyethyleneoxy (meth) acrylate, nonylphenoxypolyethyleneoxy (meth) acrylate, γ -chloro- β -hydroxypropyl- β ' - (meth) acryloyloxyethyl-phthalate, β -hydroxyethyl- β ' - (meth) acryloyloxyethyl-phthalate, β -hydroxypropyl- β ' - (meth) acryloyloxyethyl-phthalate, and an alkyl (meth) acrylate. These may be used alone or in combination of two or more.

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

[ solution 9]

In the general formula (III), R¹、R²、R³And R⁴Each 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 "EO group") or an oxypropylene group (hereinafter, sometimes referred to as "PO group"). p is a radical of₁、p₂、q₁And q is₂Each independently represents a value of 0 to 40. Wherein p is₁+q₁And p₂+q₂Are all greater than or equal to 1. When X is ethylene and Y is propylene, p₁+p₂Is 1 to 40, q₁+q₂Is 0 to 20. When X is propylene and Y is ethylene, p₁+p₂Q is 0 to 20₁+q₂Is 1 to 40. Due to the fact thatp₁、p₂、q₁And q is₂The number of structural units representing an EO group or a PO group represents an integer value in a single molecule, and a rational number as an average value in an aggregate of plural kinds of molecules. The EO group and the PO group may be present continuously in a block form or randomly.

In the general formula (III), when X and Y are both ethylene, p is more excellent in resolution and adhesion₁+p₂+q₁+q₂Can be 1-20, 1-10, or 1-7.

Examples of the compound represented by the general formula (III) include: 2, 2-bis (4- ((meth) acryloyloxypolyethoxy) phenyl) propane, 2-bis (4- ((meth) acryloyloxypolypropoxy) phenyl) propane, 2-bis (4- ((meth) acryloyloxypolyethoxypolypropoxy) phenyl) propane and the like. These may be used alone or in combination of two or more.

Examples of the bisphenol-type (meth) acrylate compound that can be commercially obtained include: 2, 2-bis (4- (methacryloyloxydiethoxy) phenyl) propane ("BPE-200" manufactured by Ninghamu chemical Co., Ltd.), 2-bis (4- (methacryloyloxypentaethoxy) phenyl) propane ("BPE-500" manufactured by Ninghamu chemical Co., Ltd or "FA-321M" manufactured by Hitachi chemical Co., Ltd.), 2-bis (4- (methacryloyloxypentadecyloxy) phenyl) propane ("BPE-1300" manufactured by Ninghamu chemical Co., Ltd.), 2-bis (4- (methacryloyloxypolyethoxy) phenyl) propane ("BP-2 EM" (EO group: 2.6 (average value)) manufactured by Kyoeisu chemical Co., Ltd.

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% based on the total amount of the solid components of the components (A) and (B), from the viewpoint of further improving chemical resistance.

In addition, 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% with respect to the total solid content of the component (B) from the viewpoint of further improving chemical resistance.

In addition, from the viewpoint of improving the 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% with respect to the total amount of the solid content of the component (a) and the component (B).

In addition, from the viewpoint of further improving the followability to the irregularities of the substrate, a compound obtained by reacting a polyhydric alcohol with an α, β -unsaturated carboxylic acid may be contained. As such a compound, polyalkylene glycol di (meth) acrylate having both EO group and PO group in the molecule, dipentaerythritol (meth) acrylate having EO group, and the like can be used. Examples of commercially available dipentaerythritol (meth) acrylate compounds having an EO group include: "DPE ALPHA-12" manufactured by Nippon Kagaku K.K., and the like. The content of dipentaerythritol (meth) acrylate having an EO group may be 1 to 10 mass%, 1.5 to 8 mass%, 2 to 8 mass%, 2.5 to 8 mass%, or 3 to 8 mass% based on the total solid content of the component (B) from the viewpoint of improving resolution.

In the molecule of the polyalkylene glycol di (meth) acrylate having both EO groups and PO groups, the EO groups and PO groups may be present continuously in blocks or randomly. Further, the PO group may be either an oxy-n-propylene group or an oxy-isopropylene group. In the (poly) oxyisopropylidene group, a secondary carbon of the propylene group may be bonded to an oxygen atom, and a primary carbon may be bonded to an oxygen atom.

As commercially available polyalkylene glycol di (meth) acrylates having both EO groups and PO groups, for example, there may be mentioned: having an EO group: 6 (average) and PO group: and (c) 12 (average value) of polyalkylene glycol di (meth) acrylate ("F A-023M", "F A-024M" manufactured by Hitachi chemical Co., Ltd.) and the like. In addition, the content of the polyalkylene glycol di (meth) acrylate having both an EO group and a PO group may be 1 to 15 mass%, 1.5 to 15 mass%, 2 to 13 mass%, or 3 to 13 mass% with respect to the total solid content of the component (B), from the viewpoint of improving the followability to the unevenness of the substrate and the resolution.

The content of the component (B) may 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). When the content of the component (B) is within this range, the resolution, adhesion and suppression of resist edge generation of the photosensitive resin composition become better, and the sensitivity and coating properties also become better.

((C) photopolymerization initiator)

The photosensitive resin composition according to the present embodiment may contain at least one kind (C) of photopolymerization initiator (hereinafter, also referred to as "component (C)"). (C) The component (B) is not particularly limited as long as it is a component capable of polymerizing the component (B), and can be appropriately selected from generally used photopolymerization initiators.

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-morpholinoacetone-1; quinones such as alkylanthraquinone; benzine ether compounds such as benzine alkyl ethers; benzine compounds such as benzine and alkylbenzine; benzil derivatives such as benzil 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, and the like. These may be used alone or in combination of two or more.

Among them, 2,4, 5-triarylimidazole dimer may be contained from the viewpoint of improvement in resolution. Examples of the 2,4, 5-triarylimidazole dimer include: 2- (o-chlorophenyl) -4, 5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4, 5-bis- (m-methoxyphenyl) imidazole dimer, and 2- (p-methoxyphenyl) -4, 5-diphenylimidazole dimer. Among them, 2- (o-chlorophenyl) -4, 5-diphenylimidazole dimer may be contained from the viewpoint of improving sensitivity stability.

As the 2,4, 5-triarylimidazole dimer, for example, 2 ' -bis (2-chlorophenyl) -4,4 ', 5,5 ' -tetraphenylbiimidazole is commercially available as B-CIM (manufactured by baotu valley chemical industries, ltd., product name).

From the viewpoint of further improving the light sensitivity and adhesiveness and further suppressing the light absorption of the component (C), the component (C) may contain at least one of 2,4, 5-triarylimidazole dimers, or may contain 2- (2-chlorophenyl) -4, 5-diphenylimidazole dimer. It should be noted that the structure of the 2,4, 5-triarylimidazole dimer may be symmetrical or asymmetrical.

The content of the 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 the components (A) and (B). When the content of the component (C) is 0.01 parts by mass or more, photosensitivity, resolution and adhesiveness tend to be improved, and when it is 30 parts by mass or less, the resist pattern shape tends to be excellent.

((D) photosensitizing agent)

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), the absorption wavelength of the active light used for exposure tends to be effectively utilized.

Examples of the component (D) include: pyrazolines, dialkylaminobenzophenones, anthracenes, coumarins, xanthinones, pyrazolines, dialkylaminobenzophenones, xanthenones, pyrazolines, dialkylaminobenzophenones, xanthenones, and pyrazolines,

Azoles, benzols

Azoles, thiazoles, benzothiazoles, triazoles, stilbenes, triazines, thiophenes, naphthalimides and triarylamines. These may be used singly or in combination of two or more. From the viewpoint of more effectively utilizing the absorption wavelength of the active light used for exposure, (D) isThe component (A) may contain pyrazolines, anthracenes, or dialkylaminobenzophenones, and may also contain dialkylaminobenzophenones. Examples of commercially available dialkylaminobenzophenones include "EAB" manufactured by Baotou chemical industries, Ltd.

When the component (D) is contained, the content thereof may be 1.0 part by mass or less, 0.5 part by mass or less, 0.15 part by mass or less, 0.12 part by mass or less, or 0.10 part by mass or less with respect to 100 parts by mass of the total amount of the solid components of the components (A) and (B). If the content of the component (D) is less than or equal to 1.0 part by mass based on 100 parts by mass of the total solid content of the components (a) and (B), deterioration in the shape of the resist pattern and the edge portion of the resist tends to be suppressed, and the resolution tends to be further improved. In addition, from the viewpoint of easily obtaining high photosensitivity and high resolution, the content of the component (D) may be 0.01 parts by mass or more relative to 100 parts by mass of the total solid content of the components (a) and (B).

((E) polymerization inhibitor)

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

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

[ solution 10]

In the general formula (I), R⁵Represents 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 alkylmercapto group having 1 to 10 carbon atoms, a carboxyalkyl group having 1 to 10 carbon atoms in the alkyl group, an alkoxy group having 1 to 20 carbon atoms or a heterocyclic group, and m and n are integers in which m is 2 or moreN is an integer of 0 or more and m + n is an integer selected from 6, and when n is an integer of 2 or more, R is⁵Each may be the same or different. The aryl group may be substituted with an alkyl group having 1 to 20 carbon atoms.

From the viewpoint of further improving the compatibility with the component (A), R⁵Can be a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. As R⁵The alkyl group having 1 to 20 carbon atoms represented by the formula (I) 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.

Examples of the compound represented by the general formula (I) include: catechol; resorcinol (resorcinol); 1, 4-hydroquinone; alkyl pyrocatechols such as 3-methylcatechol, 4-methylcatechol, 3-ethylpyrocatechol, 4-ethylpyrocatechol, 3-propylpyrocatechol, 4-propylpyrocatechol, 3-n-butylpyrocatechol, 4-n-butylpyrocatechol, 3-tert-butylpyrocatechol, 4-tert-butylpyrocatechol, and 3, 5-di-tert-butylpyrocatechol; alkylresorcinols such as 2-methylresorcinol, 4-methylresorcinol, 5-methylresorcinol (orcinol), 2-ethylresorcinol, 4-ethylresorcinol, 2-propylresorcinol, 4-propylresorcinol, 2-n-butylresorcinol, 4-n-butylresorcinol, 2-tert-butylresorcinol, and 4-tert-butylresorcinol; alkylhydroquinones such as methylhydroquinone, ethylhydroquinone, propylhydroquinone, t-butylhydroquinone and 2, 5-di-t-butylhydroquinone; pyrogallol, phloroglucinol, and the like. These may be used alone or in combination of two or more.

Among the compounds represented by the general formula (I), from the viewpoint of further improving the resolution, it may be an alkyl catechol.

(E) The content of the component (B) may be 0.001 to 0.3 part by mass, 0.01 to 0.2 part by mass, 0.02 to 0.15 part by mass, or 0.03 to 0.1 part by mass based on 100 parts by mass of the total solid content of the component (A) and the component (B). When the content of the component (E) is 0.3 parts by mass or less, the exposure time can be shortened, and the improvement of the mass production efficiency tends to be contributed. Further, when the content of the component (E) is 0.001 parts by mass or more, the photoreaction of the photocurable part can be sufficiently performed, and the reaction rate is increased, so that the resist swelling property is suppressed and the resolution tends to be further improved.

The content of the component (E) may be 0.03 to 0.4 part by mass, 0.05 to 0.2 part by mass, or 0.05 to 0.1 part by mass based on 100 parts by mass of the solid component of the component (A). When the content of the component (E) is 0.05 parts by mass or more relative to the component (a), the thermal stability of the photosensitive resin composition tends to be improved, and when the content is 0.4 parts by mass or less, the yellowing of the photosensitive resin composition tends to be suppressed.

(other Components)

The photosensitive resin composition according to the present embodiment may contain, if necessary, 0.01 to 20 parts by mass of each of dyes such as malachite green, victoria pure blue, brilliant green, and methyl violet based on 100 parts by mass of the total solid content of the component (a) and the component (B); light color developers such as tribromophenyl sulfone, colorless crystal violet, diphenylamine, benzylamine, triphenylamine, diethylaniline, o-chloroaniline and tert-butyl catechol; a thermal coloration preventing agent; plasticizers such as p-toluenesulfonamide; pigment, filler, defoaming agent, flame retardant, adhesion imparting agent, leveling agent, peeling promoter, antioxidant, perfume, developing agent, thermal crosslinking agent, and the like. These additives may be used singly or in combination of two or more.

In addition, the photosensitive resin composition according to the present embodiment may contain at least one of organic solvents as necessary for improving the handling property of the photosensitive composition or for adjusting the viscosity and the storage stability. As the organic solvent, a commonly used organic solvent can be used without particular limitation. Specific examples thereof include organic solvents such as methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N-dimethylformamide, and propylene glycol monomethyl ether, and mixed solvents thereof. These may be used alone or in combination of two or more.

< protective layer >

The photosensitive element of the present embodiment may have a protective layer laminated 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 of polyethylene, polypropylene, or the like can be used. Further, the same polymer film as the above-mentioned support film may be used, or a different polymer film may be used.

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 below.

< method for producing photosensitive element >

First, for example, a water-soluble resin containing polyvinyl alcohol is slowly added to a mixed solvent of water heated to 70 to 90 ℃ and an alcohol containing an alcohol having a carbon number of 3 or more, and stirred for about 1 hour to be uniformly dissolved, so that the solid content becomes 10 to 20 mass%, thereby obtaining a resin composition for forming a barrier layer containing polyvinyl alcohol and an alcohol having a carbon number of 3 or more. In the present specification, the term "solid content" refers to a nonvolatile component of the resin composition other than volatile substances such as water and organic solvents. That is, the term "component" refers to a component other than a solvent such as water and an organic solvent which is not volatilized and remains in the drying step, and includes a component which is liquid, syrup-like, or wax-like at room temperature of about 25 ℃.

Next, the barrier layer-forming resin composition is applied onto the support film and dried to form the barrier layer. The coating of the resin composition for forming a barrier layer on the support film can be carried out by a known method such as roll coating, comma coating, gravure coating, air knife coating, die coating, bar coating, or spray coating.

The drying of the coated resin composition for forming a barrier layer is not particularly limited as long as at least a part of the solvent such as water can be removed, and the resin composition can be dried at 70 to 150 ℃ for 5 to 30 minutes. After drying, the amount of the residual solvent in the barrier layer may be set to 2% by mass or less from the viewpoint of preventing solvent diffusion in the subsequent step.

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 application of the resin composition for forming the barrier layer, to form a photosensitive layer on the barrier layer. Next, a protective layer is laminated on the photosensitive layer formed in the above manner, whereby a photosensitive element including a support film, a barrier layer, a photosensitive layer, and a protective layer in this order can be manufactured. In addition, a photosensitive element including a support film, a barrier layer, a photosensitive layer, and a protective layer in this order can also be obtained by bonding the barrier layer formed on the support film and the photosensitive layer formed on the protective layer.

The thickness of the photosensitive layer in the photosensitive element can be selected as appropriate according to the application, and can be 1 to 200 μm, 5 to 100 μm, or 10 to 50 μm in terms of the thickness after drying. When the thickness of the photosensitive layer is 1 μm or more, industrial application is facilitated and productivity tends to be improved. Further, when the thickness of the photosensitive layer is 200 μm or less, since the photosensitivity is high, the photocurability of the resist bottom is excellent, and thus a resist pattern excellent in resolution and aspect ratio tends to be formed.

The melt viscosity of the photosensitive layer in the photosensitive element at 110 ℃ can be selected as appropriate depending on the type of the substrate in contact with the photosensitive layer, and after drying, the melt viscosity at 110 ℃ can be 50 to 10000 pas, 100 to 5000 pas, or 200 to 1000 pas. When the melt viscosity at 110 ℃ is 50 pas or higher, wrinkles and voids do not occur in the laminating step, and the productivity tends to be improved. Further, if the melt viscosity at 110 ℃ is 10000Pa · s or less, the adhesiveness to the substrate in the lamination step is improved, and poor adhesion tends to be reduced.

The form of the photosensitive element according to the present embodiment is not particularly limited. For example, the sheet-like shape may be obtained by winding the sheet-like material around a core. When the film is wound in a roll shape, the film may be wound so that the support film is on the outer side. Examples of the core include plastics such as polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, and ABS resin (acrylonitrile-butadiene-styrene copolymer).

The end face of the roll of photosensitive element obtained in the above manner may be provided with an end face spacer from the viewpoint of end face protection, or may be provided with a moisture-proof end face spacer from the viewpoint of a weld margin. As a packaging method, a black sheet having low moisture permeability may be wrapped and packaged.

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

[ method for Forming resist Pattern ]

The method for forming a resist pattern according to the present embodiment includes: (i) a step of disposing the photosensitive layer, the barrier layer, and the support film on the substrate in this order from the substrate side using the photosensitive element (hereinafter, also referred to as "(i) photosensitive layer and barrier layer forming step"); (ii) a step of removing the support film and exposing the photosensitive layer to active light through the barrier layer (hereinafter, also referred to as "ii) an exposure step"); and (iii) a step of removing the uncured portion of the photosensitive layer and the barrier layer from the substrate (hereinafter, also referred to as a "developing step") and may include other steps as necessary. The resist pattern may be referred to as a photo-cured material pattern of the photosensitive resin composition, or may be referred to as an uneven pattern. In addition, the resist pattern in this embodiment mode can be used as a resist or can be used for other applications such as a protective film according to the purpose.

(i) photosensitive layer and Barrier layer Forming Process)

In the photosensitive layer and barrier layer forming step, the photosensitive element is used to form the photosensitive layer and barrier layer on the substrate. The substrate is not particularly limited, and a circuit forming substrate including an insulating layer and a conductor layer formed on the insulating layer, a die pad (lead frame substrate) such as an alloy substrate, or the like can be generally used.

As a method for forming the photosensitive layer and the barrier layer on the substrate, for example, when a photosensitive element having a protective layer is used, after the protective layer is removed, the photosensitive layer of the photosensitive element is pressed against the substrate while heating, and the photosensitive layer and the barrier layer are formed on the substrate. This makes it possible to obtain a laminate comprising a substrate, a photosensitive layer, a barrier layer, and a support film in this order.

When the photosensitive layer and the barrier layer are formed using a photosensitive element, the photosensitive layer and the barrier layer may be formed under reduced pressure from the viewpoint of adhesiveness and conformability. The heating during the compression bonding can be carried out at a temperature of 70-130 ℃, and the compression bonding can be carried out at a pressure of 0.1-1.0 MPa (1-10 kgf/cm)²) Under the above-mentioned pressure, these conditions can be appropriately selected as required. Note that, if the photosensitive layer of the photosensitive element is heated to 70 to 130 ℃, the substrate does not need to be subjected to a preheating treatment in advance, but the substrate may be subjected to a preheating treatment in order to further improve the adhesion and the follow-up property.

(ii) Exposure Process)

In the exposure step, the support film is removed, and the photosensitive layer is exposed to active light through the barrier layer. Thus, the exposed portion irradiated with the active light beam can be photocured to form a photocured portion (latent image), and the unexposed portion not irradiated with the active light beam can be photocured to form a photocured portion. When the photosensitive layer and the barrier layer are formed using the 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 having excellent resolution and resist pattern shape can be formed.

As the exposure method, a known exposure system can be applied, and examples thereof include: a method (mask exposure method) of irradiating an active ray in an image form through a negative or positive mask pattern called an original (art); an LDI (Laser Direct Imaging) exposure mode; or a method (projection exposure method) in which an active light beam for projecting an image of a photomask is used to irradiate the photomask image in an image form through a lens. Among them, a projection exposure system is used from the viewpoint of excellent resolution. That is, the photosensitive element and the like according to the present embodiment are applied to a projection exposure system. The projection exposure system may be referred to as an exposure system using an active light beam with attenuated energy.

The light source of the active light is not particularly limited as long as it is a known light source that is generally used, and for example, there can be used: a carbon arc lamp, a mercury vapor arc lamp, an ultra-high pressure mercury lamp, a xenon lamp, a gas laser such as an argon laser, a solid laser such as a YAG laser, a semiconductor laser such as a gallium nitride based blue-violet laser, and the like. Further, a floodlight bulb for photography, a sun lamp, or the like can be used as a light source that efficiently emits visible light. Among them, from the viewpoint of improving the resolution and the alignment in a well-balanced manner, a light source capable of emitting i-ray monochromatic light having an exposure wavelength of 365nm, a light source capable of emitting h-ray monochromatic light having an exposure wavelength of 405nm, or a light source capable of emitting active light having an exposure wavelength of ihg mixed rays, may be used, and among these, a light source capable of emitting i-ray monochromatic light having an exposure wavelength of 365nm may be used. Examples of the light source capable of emitting i-ray monochromatic light having an exposure wavelength of 365nm include an ultra-high pressure mercury lamp and the like.

(iii) developing step

In the developing step, the uncured portion of the photosensitive layer and the barrier layer are removed from the substrate. In the developing step, a resist pattern including a photocured portion obtained by photocuring the photosensitive layer is formed on the substrate. When the barrier layer is water-soluble, the barrier layer may be removed by washing with water, and then uncured portions other than the photocured portions may be removed by a developer. The developing method may be wet development.

In the case of wet development, development can be carried out by a known wet development method using a developer corresponding to the photosensitive resin composition. Examples of the wet development method include: the immersion method, the suspended immersion method, the high-pressure spraying method, and the method using brushing, tapping, scraping, shaking immersion, or the like are preferable from the viewpoint of improving the resolution. These wet development methods may be used alone or in combination of two or more.

The developer can be appropriately selected according to the composition of the photosensitive resin composition. Examples thereof include an aqueous alkaline solution and an organic solvent developer.

From the viewpoint of safety, stability, and good operability, an alkaline aqueous solution can be used as the developer. Examples of the alkali of the alkaline aqueous solution include alkali hydroxides such as lithium, sodium, or potassium hydroxide, alkali 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.

As the alkaline aqueous solution used for development, a dilute sodium carbonate solution of 0.1 to 5% by mass, a dilute potassium carbonate solution of 0.1 to 5% by mass, a dilute sodium hydroxide solution of 0.1 to 5% by mass, a dilute sodium tetraborate solution of 0.1 to 5% by mass, or the like can be used. In addition, the pH of the alkaline aqueous solution used for development can be set to be in the range of 9-11, and the temperature of the alkaline aqueous solution can be adjusted according to the developability of the photosensitive layer. In addition, in the alkaline aqueous solution, for example, a surfactant, a defoaming agent, a small amount of an organic solvent for promoting development, and the like may be mixed. Examples of the organic solvent used in the alkaline aqueous solution include: 3-acetol, 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.

Examples of the organic solvent used in the organic solvent developer include: 1,1, 1-trichloroethane, N-methylpyrrolidone, N-dimethylformamide, cyclohexanone, methyl isobutyl ketone and gamma-butyrolactone. From the viewpoint of preventing ignition, these organic solvents may be added with water to be in the range of 1 to 20 mass% to prepare an organic solvent developer.

(other steps)

The method for forming a resist pattern according to the present embodiment may include the steps of: removing uncured part in developing processHeating at 60-250 deg.C or 0.2-10J/cm²Exposure with an exposure amount of (c), thereby further curing the resist pattern.

[ method for producing printed Wiring Board ]

The method for manufacturing a printed wiring board according to the present embodiment includes a step of forming a conductor pattern by performing etching treatment or plating treatment on the substrate on which the resist pattern is formed by the above-described method for forming a resist pattern, and may include other steps such as a resist pattern removal step as necessary. 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 photosensitive element, and is more suitably applied to a method for forming a conductor pattern by plating treatment. The conductor pattern may be referred to as a circuit.

In the etching treatment, the conductor layer of the substrate not covered with the resist is etched and removed using the resist pattern formed on the substrate provided with the conductor layer as a mask, thereby forming the conductor pattern.

The method of the etching treatment is appropriately selected depending on the conductor layer to be removed. Examples of the etching solution include a copper chloride solution, an iron chloride solution, an alkaline etching solution, and a hydrogen peroxide etching solution, and an iron chloride solution can be used from the viewpoint of a good etching factor.

On the other hand, in the plating treatment, copper, solder, or the like is plated on the conductor layer of the substrate not covered with the resist using a resist pattern formed on the substrate provided with the conductor layer as a mask. After the plating treatment, the resist is removed by removing a resist pattern described later, and the conductor layer covered with the resist is further etched to form a conductor pattern.

The plating treatment may be an electroplating treatment or an electroless plating treatment, and may be an electroless plating treatment. Examples of the electroless plating treatment include: copper plating such as copper sulfate plating and copper pyrophosphate plating; high uniformity (high throw) solder plating and the like; nickel plating such as watts bath (nickel sulfate-nickel chloride) plating and nickel sulfamate plating; gold plating such as hard gold plating, soft gold plating, and the like.

After the etching treatment or plating treatment, the resist pattern on the substrate is removed. The resist pattern can be removed, for example, by an aqueous solution having a stronger alkali than the alkaline aqueous solution used in the developing step. Examples of the strongly alkaline aqueous solution include 1 to 10 mass% sodium hydroxide aqueous solution and 1 to 10 mass% potassium hydroxide aqueous solution. Among them, 1 to 5 mass% aqueous sodium hydroxide solution or aqueous potassium hydroxide solution can be used.

Examples of the resist pattern removal method include a dipping method and a spraying method, and these methods may be used alone or in combination.

When the resist pattern is removed after the plating process is performed, the conductor layer covered with the resist is further etched by an etching process to form a conductor pattern, whereby a desired printed wiring board can be manufactured. The method of the etching treatment in this case is appropriately selected depending on the conductor layer to be removed. For example, the above-mentioned etching solution can be used.

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 also to the manufacture of a printed wiring board or the like having small-diameter through holes.

The method for manufacturing a printed wiring board according to the present embodiment can be suitably used for manufacturing a high-density package substrate, particularly for manufacturing a wiring board by a semi-additive method. Fig. 2 shows an example of a manufacturing process of a wiring board using the semi-additive method.

In fig. 2 a, a substrate (circuit forming substrate) having a conductor layer 40 formed on an insulating layer 50 is prepared. The conductive layer 40 is, for example, a copper layer. In fig. 2(b), the photosensitive layer 30 and the barrier layer 20 are formed on the conductive layer 40 of the substrate by the photosensitive layer and barrier layer forming step. In fig. 2(c), in the exposure step, the photosensitive layer 30 is irradiated with the actinic ray 80, which projects a photomask image, through the barrier layer 20, thereby forming a photocurable portion on the photosensitive layer 30. In fig. 2 d, a region (including the barrier layer) other than the photocured portion formed in the exposure step is removed from the substrate in the development step, thereby forming a resist pattern 32 as a photocured portion on the substrate. In fig. 2(e), a plating layer 60 is formed on the conductor layer 40 of the substrate not covered with the resist by a plating process using the resist pattern 32 as a mask, which is a photocurable part. In fig. 2(f), after the resist pattern 32 as a photocured portion is peeled off by an aqueous solution of a strong base, the conductor layer 40 covered with the resist pattern 32 is removed by flash etching (flash etching), thereby forming a conductor pattern 70 including the plating layer 62 after etching treatment and the conductor layer 42 after etching treatment. The conductive layer 40 and the plating layer 60 may be made of the same material or different materials. When the conductive layer 40 and the plating layer 60 are made of the same material, the conductive layer 40 and the plating layer 60 can be integrated. While the projection exposure method is described with reference to fig. 2, the resist pattern 32 may be formed by a mask exposure method or an LDI exposure method in combination.

While the present disclosure has been described with reference to the preferred embodiments, the present disclosure is not limited to the embodiments.

Examples

Hereinafter, the present disclosure will be described more specifically based on examples, but the present disclosure is not limited to the following examples. Unless otherwise specified, "part" and "%" are based on mass.

First, a binder polymer (a-1) shown in tables 1 to 3 below was synthesized in accordance with synthesis example 1.

< Synthesis example 1 >

A solution a was prepared by mixing 125g of methacrylic acid, 25g of methyl methacrylate, 125g of benzyl methacrylate, and 225g of styrene as polymerizable monomers with 1.5g of azobisisobutyronitrile.

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

On the other hand, 400g of a mixed solution of methyl cellosolve and toluene (hereinafter, also referred to as "mixed solution x") in a mass ratio of 3:2 was added to a flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel, and a nitrogen introduction tube, and the mixture was stirred while being purged with nitrogen and heated to 80 ℃.

The solution a was added dropwise to the mixed solution x in the flask over 4 hours with the dropping rate fixed, and then stirred at 80 ℃ for 2 hours. Then, the solution b was added dropwise to the solution in the flask over 10 minutes with the dropping rate fixed, and the solution in the flask was stirred at 80 ℃ for 3 hours. Further, the solution in the flask was heated to 90 ℃ over 30 minutes, and after keeping the temperature at 90 ℃ for 2 hours, it was cooled to room temperature to obtain a solution of the binder polymer (a-1). The solution of the binder polymer (a-1) was prepared so that the nonvolatile content (solid content) became 50 mass% after the mixed solution x was added.

The weight average molecular weight of the adhesive polymer (A-1) was 50,000, and the acid value was 163 mgKOH/g. The acid value is measured by a neutralization titration method. Specifically, the measurement was carried out in the following manner: after 30g of acetone was added to 1g of the binder polymer solution and the solution was further uniformly dissolved, an appropriate amount of phenolphthalein as an indicator was added to the binder polymer solution, and titration was performed using a 0.1N KOH aqueous solution. The weight average molecular weight is measured by Gel Permeation Chromatography (GPC) and is derived by conversion using a standard curve of standard polystyrene. The GPC conditions are shown below.

GPC conditions

A pump: hitachi L-6000 type (Hitachi, Co., Ltd.)

A chromatographic column: a total of 3 columns (column size:

are all made by Hitachi chemical Co., Ltd

Gelpack GL-R420

Gelpack GL-R430

Gelpack GL-R440

Eluent: tetrahydrofuran (THF)

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

Measuring temperature: 25 deg.C

Flow rate: 2.05 mL/min

A detector: hitachi L-3300 type RI (product name, manufactured by Hitachi Kagaku K.K.)

< preparation of resin composition for Forming Barrier layer >

Next, the components shown in tables 1 to 3 below were mixed in the amounts shown in the tables (unit: parts by mass), to obtain a resin composition for forming a barrier layer. Specifically, the water-soluble resin was slowly added to water and alcohols at room temperature, and the whole amount was added, followed by heating to 90 ℃. After reaching 90 ℃, the mixture was stirred for 1 hour and cooled to room temperature to obtain a resin composition for forming a barrier layer. In tables 1 to 3, the amounts of the components other than the solvent are all based on the solid content.

< preparation of photosensitive resin composition >

Then, the components shown in tables 1 to 3 below were mixed in the amounts shown in the tables (unit: parts by mass), to obtain photosensitive resin compositions.

[ Table 1]

[ Table 2]

[ Table 3]

The details of each component in tables 1 to 3 are as follows.

(Water-soluble resin)

*1: polyvinyl alcohol PVA-205 (product name, saponification degree 87 mol%, average polymerization degree 500, manufactured by Coli, Ltd.)

*2: polyvinyl alcohol PVA-203 (product name, saponification degree 87 mol%, average polymerization degree 300, manufactured by Coli Co., Ltd.)

*3: polyvinyl alcohol PVA-210 (product name, saponification degree 87 mol%, average polymerization degree 1000 manufactured by Coli Co., Ltd.)

*4: polyvinylpyrrolidone K-30 (product name, manufactured by Japan catalyst Co., Ltd.)

(A) The components: adhesive polymer

*5: (A-1) (Binder Polymer (A-1) obtained in Synthesis example 1)

Methacrylic acid/methyl methacrylate/benzyl methacrylate/styrene (mass ratio) 25/5/25/45, weight average molecular weight 50,000, solid content 50 mass%, and cellosolve/toluene (mass ratio) 3/2

(B) The components: photopolymerizable compound having ethylenically unsaturated bond

*6: FA-321M (product name of Hitachi Kabushiki Kaisha)

2, 2-bis (4- (methacryloxypentaethoxy) phenyl) propane

*7: FA-024M (product name of Hitachi Kabushiki Kaisha)

EOPO modified dimethacrylate

*8: BPE-200 (New Zhongcun chemical industry Co., Ltd., product name)

2, 2-bis (4- (methacryloyloxydiethoxy) phenyl) propane

*9: BP-2EM (product name of Kyoeisha chemical Co., Ltd.)

2, 2-bis (4- (methacryloxypolyethoxy) phenyl) propane

*10: DPEA-12 (manufactured by Nippon Kagaku Co., Ltd., product name)

Ethylene oxide modified dipentaerythritol hexaacrylate

(C) The components: photopolymerization initiator

*11: B-CIM (product name of Baotu chemical industries Co., Ltd.)

2,2 ' -bis (2-chlorophenyl) -4,4 ', 5,5 ' -tetraphenylbenzimidazole

(D) The components: photosensitizing agents

*12: EAB (Baotu chemical industry Co., Ltd., product name)

4, 4' -bis (diethylamino) benzophenone

(E) The components: polymerization inhibitor

*13: TBC (DIC corporation)

4-tert-butylcatechol

Examples 1 to 15 and comparative examples 1 to 7

< production of photosensitive element >

As a support film of the photosensitive element, PET films shown in tables 1 to 3 were prepared.

Details of the PET films shown in tables 1 to 3 are as follows.

FB 40: biaxially oriented PET film having 3-layer structure and having lubricant layer on front and back surfaces (manufactured by Toray corporation, product name, thickness: 16 μm)

A1517: biaxially oriented PET film having a 2-layer structure and a lubricant layer on one surface (product name, thickness: 16 μm, manufactured by Toyo Seisaku K.K.)

G2H: biaxially oriented PET film (manufactured by Diren DuPont film Co., Ltd., product name, thickness: 15.5 μm) having a single layer structure (lubricant-doped type) containing a lubricant

(preparation of Barrier layer)

Next, the barrier layer-forming resin composition was applied onto a PET film (support film) so as to have a uniform thickness, and dried for 10 minutes by a hot air convection dryer at 95 ℃ to form a barrier layer having a thickness of 5 μm after drying. When the density of the lubricant is different on both sides of the PET film, the barrier layer is formed on the side of the PET film having less lubricant, and when the lubricant layer is provided on the side of the PET film, the barrier layer is formed on the side of the PET film on the lubricant layer side.

(production of photosensitive layer)

Next, the photosensitive resin composition was coated on the barrier layer of the support film so that the thickness was uniform, and dried for 10 minutes by a hot air convection dryer at 100 ℃ to form a photosensitive layer having a thickness of 10 μm after drying.

Next, a protective film (protective layer) made of polyethylene (product name "NF-15" manufactured by tamapol corporation) was bonded to the photosensitive layer, and a photosensitive element in which a PET film (support film), a barrier layer, a photosensitive layer, and a protective layer were sequentially stacked was obtained.

< measurement of residual alcohol amount >

The amount of residual alcohol in the formed barrier layer was measured by gas chromatography mass spectrometry. The measurement conditions for gas chromatography mass spectrometry are as follows. The term "amount of residual alcohol in the barrier layer" in tables 1, 2 and 3 indicates the amount of alcohol having 3 or more carbon atoms. Note that "< 1.0" means more than 0 and less than 1.0.

(conditions for measurement of gas chromatography mass spectrometry)

A measuring device: GC/MS QP-2010 (product name, Shimadzu corporation)

A chromatographic column: HP-5MS (name of Agilent science and technology Co., Ltd.)

Oven temperature (Oven Temp): heating at 40 deg.C for 5 min, and heating to 300 deg.C at a rate of 15 deg.C/min

Carrier gas: helium, 1.0mL/min

Interface temperature: 280 deg.C

Ion source temperature: 250 deg.C

Sample introduction amount: 0.1mL

< production of laminate >

A copper surface of a copper-clad laminate (substrate, "MCL-E-67", manufactured by Hitachi chemical Co., Ltd.) as an epoxy glass material, in which copper foils having a thickness of 12 μm were laminated on both surfaces thereof, was subjected to acid treatment, washed with water, and dried with an air flow. The photosensitive elements are respectively pressed onto the copper-clad laminate by heating the copper-clad laminate to 80 ℃ and peeling off the protective layer while the photosensitive layer is in contact with the copper surface. The crimping was carried out using a 110 ℃ hot roll at a roll speed of 1.0 m/min under a pressure of 0.40 MPa. Thus, a laminate in which the substrate, the photosensitive layer, the barrier layer, and the support film are laminated in this order was obtained. These laminates were used as test pieces in the tests described below. HLM-3000 (product name, manufactured by Dachen Laminator Co., Ltd.) was used as a Laminator.

< evaluation of peeling Property of support film >

The test piece was left to stand at 23 ℃ and 50% humidity for 1 hour. Then, the support film, which was a PET film, was peeled from the test piece at a peeling angle of 135 degrees and a peeling speed of 500 mm/sec, and the support film peeling property was evaluated according to the following evaluation criteria. The evaluation results are shown in tables 4 to 6 below.

A: the PET film as only the support film was easily peeled off.

B: the barrier layer is attached to a part of the support film to be peeled off, or the support film cannot be peeled off.

< evaluation of resolution >

In order to examine the resolution, after the support film was peeled off from the test piece, a 41-stage Hitachi exposure table was placed on the barrier layer of the test piece, a glass mask having a pattern for resolution evaluation having a line width/space width of z/z (z is 2 to 20 (varying at 1 μm intervals)) (unit: μm) was placed thereon, and the photosensitive layer was exposed through the barrier layer using an irradiation energy at the time when the number of remaining stages after the development of the 41-stage Hitachi exposure table became 8 using a projection exposure machine (manufactured by Ushio Motor Co., Ltd., product name UX-2240SM-XJ01) having a high-pressure mercury lamp with a wavelength of 365 nm. After exposure, the test piece was washed with water at room temperature to remove the barrier layer. Next, the photosensitive layer was spray-developed at 30 ℃ for 2 times the shortest development time using a1 mass% aqueous solution of sodium carbonate to remove unexposed portions. Here, the shortest development time is obtained by measuring the time during which the unexposed portion is completely removed by the above-described development treatment. The minimum value (unit: μm) of the interval width between the line portions (exposed portions) from which the unexposed portions were completely removed by the development treatment was used as an index for the resolution evaluation. A smaller value means a better resolution. The results are shown in tables 4 to 6 below.

< evaluation of resist Pattern shape >

The cross-sectional shape of the resist pattern having a line width/space width of 10/10 (unit: μm) was observed by a Scanning Electron Microscope (SEM) with respect to the substrate evaluated in the above-described evaluation of the resolution. The sectional shape of the resist pattern is shown in tables 4 to 6 below as an evaluation of the resist pattern shape.

In the photosensitive elements of comparative examples 1 to 7, the support film peeling property was deteriorated, and the resist pattern could not be formed, and therefore, the resolution and the resist pattern shape could not be evaluated.

< evaluation of transparency of Barrier layer solution >

As a reference sample, a composition was prepared in the same manner as in the resin compositions for forming a barrier layer of examples 1 to 15 and comparative examples 1 to 7, except that the alcohol in the resin compositions for forming a barrier layer of examples 1 to 15 and comparative examples 1 to 7 was not used. Then, the transparency of the resin composition solutions for forming a barrier layer (hereinafter, also referred to as "barrier layer solutions") of examples 1 to 15 and comparative examples 1 to 7 and the transparency of the reference sample were visually observed and evaluated as follows. The evaluation results are shown in tables 4 to 6 below.

A: the turbidity of the barrier layer solution was not more than the same degree as that of the reference sample.

B: the barrier solution produced more turbidity than the reference sample.

< evaluation of transparency of Barrier layer >

The resin compositions for forming a barrier layer of examples 1 to 15 and comparative examples 1 to 7 were coated on a support film so that the thickness became uniform, and dried for 10 minutes by a hot air convection dryer at 95 ℃. As a reference sample, a composition was prepared in the same manner as the resin compositions for forming a barrier layer of examples 1 to 15 and comparative examples 1 to 7 except that the alcohol in the resin compositions for forming a barrier layer of examples 1 to 15 and comparative examples 1 to 7 was not used, and a barrier layer was formed using the composition. Then, the appearance of the barrier layer was visually observed and evaluated as follows. The evaluation results are shown in tables 4 to 6 below.

A: the degrees of turbidity and void formation in the barrier layer were equal to or less than the reference sample.

B: more turbidity or voids were generated in a part or the whole of the barrier layer as compared with the reference sample.

[ Table 4]

[ Table 5]

[ Table 6]

When the high-resolution projection exposure machine was used to perform exposure under the condition of a low energy with a residual stage number of 8 stages, it was confirmed that examples 1 to 15 had high releasability between the support film and the barrier layer, whereas comparative examples 1 to 7 had low releasability between the support film and the barrier layer.

Industrial applicability

As described above, according to the present disclosure, it is possible to provide 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 improve the peelability between the barrier layer and a support film without using a peeling accelerator.

Description of the symbols

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 treatment, 50: insulating layer, 60: plating layer, 62: plating layer after etching treatment, 70: conductor pattern, 80: and (3) active rays.

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 a monohydric alcohol having 3 or more and 6 or less carbon atoms,

the photosensitive element is used for a method for forming a resist pattern, and the method for forming a resist pattern includes:

a step of disposing the photosensitive layer, the barrier layer, and the support film on a substrate in this order from the substrate side using the photosensitive element;

removing the support film, and exposing the photosensitive layer with active light through the barrier layer; and

and removing the uncured portion of the photosensitive layer and the barrier layer from the substrate.

2. The photosensitive element according to claim 1, wherein the monohydric alcohol having 3 or more and 6 or less carbon atoms contains at least one selected from the group consisting of compounds represented by the following chemical formulas (1) to (3) and compounds represented by the following general formula (4),

[ solution 1]

[ solution 2]

[ solution 3]

[ solution 4]

In the general formula (4), R¹¹Represents an alkyl group, R¹²Represents an alkylene group, R¹¹And R¹²The sum of the carbon numbers of the groups (a) is greater than or equal to 3 and less than or equal to 6.

3. The photosensitive element according to claim 1 or 2, wherein the solubility of the monohydric alcohol having a carbon number of 3 or more and 6 or less in water at 20 ℃ is 300mL of the monohydric alcohol having a carbon number of 3 or more and 6 or less per 100mL of water.

4. The photosensitive element according to claim 1 or 2, wherein a content of the monohydric alcohol having a carbon number of 3 or more and 6 or less in the barrier layer exceeds 0% by mass and 2.0% by mass or less based on the total amount of the barrier layer.

5. The photosensitive element according to claim 1 or 2, wherein the water-soluble resin contains polyvinyl alcohol.

6. The photosensitive element according to claim 1 or 2, wherein the support film is a polyester film.

7. A resin composition for forming a barrier layer, which is used for forming a barrier layer in a photosensitive element comprising a support film, a barrier layer and a photosensitive layer in this order,

removing the uncured portion of the photosensitive layer and the barrier layer from the substrate,

the resin composition for forming a barrier layer contains a water-soluble resin, a monohydric alcohol having 3 or more and 6 or less carbon atoms, and water.

8. The resin composition for forming a barrier layer according to claim 7, wherein the monohydric alcohol having 3 or more and 6 or less carbon atoms contains at least one selected from the group consisting of compounds represented by the following chemical formulas (1) to (3) and compounds represented by the following general formula (4),

[ solution 5]

[ solution 6]

[ solution 7]

[ solution 8]

9. The barrier layer-forming resin composition according to claim 7 or 8, wherein the monohydric alcohol having a carbon number of 3 or more and 6 or less has a solubility in water at 20 ℃ of 3 or more and 6 or less per 100mL of water and 300mL of the monohydric alcohol having a carbon number of 3 or more and 6 or less.

10. The resin composition for forming a barrier layer according to claim 7 or 8, wherein the content of the monohydric alcohol having a carbon number of 3 or more and 6 or less is 100 to 500 parts by mass with respect to 500 parts by mass of water.

11. The barrier layer-forming resin composition according to claim 7 or 8, wherein the water-soluble resin contains polyvinyl alcohol.

12. A method for forming a resist pattern includes:

a step of disposing a photosensitive layer, a barrier layer and a support film in this order from the substrate side on a substrate using the photosensitive element according to any one of claims 1 to 6;

13. A method for manufacturing a printed wiring board, comprising: a step of forming a conductor pattern by performing etching treatment or plating treatment on the substrate on which the resist pattern is formed by the method for forming a resist pattern according to claim 12.