JP7415443B2 - Photosensitive resin composition, dry film using the same, printed wiring board, and method for producing printed wiring board - Google Patents

Description

The present invention relates to a photosensitive resin composition, a dry film using the same, a printed wiring board, and a method for manufacturing a printed wiring board.

In the field of printed wiring board manufacturing, permanent mask resists are formed on printed wiring boards. A permanent mask resist has the role of preventing corrosion of conductor layers and maintaining electrical insulation between conductor layers when a printed wiring board is used. In recent years, permanent mask resists have been used to prevent solder from adhering to unnecessary parts of the conductor layer of printed wiring boards during processes such as flip-chip mounting and wire bonding mounting of semiconductor elements on printed wiring boards via solder. , it also has a role as a solder resist film.

Conventionally, permanent mask resists used in the production of printed wiring boards have been produced by screen printing using a thermosetting resin composition or by a photographic method using a photosensitive resin composition. For example, in flexible wiring boards using mounting methods such as FC (Flip Chip), TAB (Tape Automated Bonding), and COF (Chip On Film), IC chips, electronic components or LCD (Liquid Crystal Display) panels, and connections Except for the wiring portion, a thermosetting resin paste is screen printed and thermally cured to form a permanent mask resist (for example, see Patent Document 1).

In addition, in semiconductor package substrates such as BGA (Ball Grid Array) and CSP (Chip Size Package) mounted on electronic components, (1) flip-chip mounting of semiconductor elements on the semiconductor package substrate via solder is required. In order to (2) wire-bond a semiconductor element and a semiconductor package substrate, or (3) solder-bond a semiconductor package substrate onto a motherboard substrate, it is necessary to remove the permanent mask resist at the bonded portion. There is. Therefore, to form this permanent mask resist, a photographic method is used in which a photosensitive resin composition is applied and dried, then selectively irradiated with active light such as ultraviolet rays to cure it, and only the unirradiated areas are removed by development to form an image. is used. The photographic method is suitable for mass production due to its good workability, and is therefore widely used in the electronic material industry for image formation of photosensitive resin compositions (see, for example, Patent Documents 2 and 3). As exposure machines used for irradiation, mask-less contact type projection exposure machines and mask-free direct writing exposure machines are widely known. Direct-draw exposure machines that do not require masks are expected to become more widespread in the future due to their high productivity. Furthermore, as wiring boards become smaller and thinner year by year, the solder resists used therein are required to have high reliability such as HAST (High Accelerated Stress Test) resistance.

Japanese Patent Application Publication No. 2003-198105 Japanese Patent Application Publication No. 2011-133851 International Publication No. 2013/022068

However, in applications where high reliability is required, such as those mentioned above, conventional photosensitive resin compositions not only have a resolution that is compatible with direct exposure machines, but also have the ability to satisfy HAST resistance. There was room for improvement.

Furthermore, in recent years, with the miniaturization and higher performance of electronic devices, the size of the hole diameter in permanent mask resist and the distance between the centers of the holes have tended to become smaller. A fine pattern with a hole diameter of 80 μm and a distance between the centers of the holes of 80 μm is used. For example, in flip-chip mounting, recently, photosensitive resin compositions are required to have improved reliability such as HAST resistance and crack resistance in addition to resolution.

An object of the present invention is to prevent undercuts in which the bottom of a resist pattern is gouged out and to prevent the top of the resist pattern from being missing, regardless of the type of exposure machine, and to prevent the occurrence of undercuts in which the bottom of the resist pattern is gouged out, and to prevent the occurrence of chipping of the top of the resist pattern. It is possible to form a resist pattern with an excellent resist shape, in which the line width is less likely to be larger than that of the surface area (that is, the linearity of the resist pattern outline is good), and it also has excellent insulation reliability and crack resistance. An object of the present invention is to provide a photosensitive resin composition having excellent reliability, a dry film using the same, a printed wiring board, and a method for producing a printed wiring board.

As a result of extensive research to solve the above problems, the present inventors have discovered that a polymerization inhibitor is added to a composition containing an acid-modified vinyl group-containing epoxy resin, a photopolymerization initiator, and a photopolymerizable compound. It was discovered that the problem could be solved by blending the problem, and the present invention was completed. That is, the present invention provides the following photosensitive resin composition, a dry film using the same, a printed wiring board, and a method for producing a printed wiring board.

[1] A photosensitive resin composition containing (A) an acid-modified vinyl group-containing epoxy resin, (B) a photopolymerization initiator, (C) a polymerization inhibitor, and (D) a photopolymerizable compound.
[2] The photopolymerization initiator of component (B) is a group selected from the group consisting of an amino group, a dimethylamino group, a diethylamino group, a dibutylamino group, a hydroxyl group, a methoxy group, an ethoxy group, a butoxy group, and a phenyl group. The photosensitive resin composition according to the above [1], which is a benzophenone compound having at least one.
[3] The acid-modified vinyl group-containing epoxy resin of the component (A) is at least one acid-modified vinyl group-containing epoxy resin (A1) synthesized using a bisphenol novolac type epoxy resin (a1) and the epoxy resin. The above [1] contains at least one selected from the group consisting of at least one acid-modified vinyl group-containing epoxy resin (A2) synthesized using an epoxy resin (a2) different from (a1). ] or the photosensitive resin composition according to [2].
[4] In the above [3], the epoxy resin (a2) is at least one selected from the group consisting of a novolac type epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and a triphenolmethane type epoxy resin. The photosensitive resin composition described.
[5] The acid-modified vinyl group-containing epoxy resin (A1) contains a saturated or unsaturated group in the resin (A1') obtained by reacting the epoxy resin (a1) with the vinyl group-containing monocarboxylic acid (b). The resin is obtained by reacting a containing polybasic acid anhydride (c), and the acid-modified vinyl group-containing epoxy resin (A2) reacts with the epoxy resin (a2) and a vinyl group-containing monocarboxylic acid (b). The photosensitive resin composition according to [3] or [4] above, which is a resin obtained by reacting a saturated or unsaturated group-containing polybasic acid anhydride (c) with a resin (A2') obtained by reacting a polybasic acid anhydride (c) containing a saturated or unsaturated group.
[6] The bisphenol novolac type epoxy resin (a1) is a bisphenol novolac type epoxy resin having a structural unit represented by the following general formula (I) and a bisphenol novolak type epoxy resin having a structural unit represented by the following general formula (II). The epoxy resin (a2) is at least one type selected from the group consisting of type epoxy resins, and the epoxy resin (a2) is a novolac type epoxy resin having a structural unit represented by the following general formula (III), and a novolac type epoxy resin having a structural unit represented by the following general formula (IV). [3] to [5] above, which is at least one selected from the group consisting of a bisphenol-type epoxy resin having a structural unit represented by the following general formula (V) and a triphenolmethane-type epoxy resin having a structural unit represented by the following general formula (V). The photosensitive resin composition according to any one of the above.

[In general formula (I), R ¹¹ represents a hydrogen atom or a methyl group, and Y ¹ and Y ² each independently represent a hydrogen atom or a glycidyl group. A plurality of R ^11s may be the same or different, and at least one of Y ¹ and Y ² represents a glycidyl group. ]
[In general formula (II), R ¹² represents a hydrogen atom or a methyl group, and Y ³ and Y ⁴ each independently represent a hydrogen atom or a glycidyl group. A plurality of R ^12s may be the same or different, and at least one of Y ³ and Y ⁴ represents a glycidyl group. ]
[In general formula (III), R ¹³ represents a hydrogen atom or a methyl group, Y ⁵ represents a hydrogen atom or a glycidyl group, and the molar ratio of the hydrogen atom to the glycidyl group (hydrogen atom/glycidyl group) is 0/ It is 100 to 30/70. ]
[In general formula (IV), R ¹⁴ represents a hydrogen atom or a methyl group, Y ⁶ represents a hydrogen atom or a glycidyl group, and the molar ratio of the hydrogen atom to the glycidyl group (hydrogen atom/glycidyl group) is 0/ 100 to 30/70, and multiple R ^14s may be the same or different. ]
[In general formula (V), Y ⁷ represents a hydrogen atom or a glycidyl group, a plurality of Y ^7s may be the same or different, and at least one Y ⁷ is a glycidyl group. ]

[7] The component (A) contains at least one kind of the acid-modified vinyl group-containing epoxy resin (A1) and at least one kind of the acid-modified vinyl group-containing epoxy resin (A2), The photosensitive resin composition according to any one of [3] to [6] above.
[8] The bisphenol novolac type epoxy resin (a1) has a structural unit represented by the general formula (I), and the epoxy resin (a2) is represented by the general formula (IV). The photosensitive resin composition according to [7] above, which is a bisphenol A-type epoxy resin or a bisphenol F-type epoxy resin containing a structural unit.
[9] The photosensitive composition according to any one of [3] to [6] above, wherein the component (A) contains at least one acid-modified vinyl group-containing epoxy resin (A2). Resin composition.
[10] The photosensitive resin composition according to [9] above, wherein the epoxy resin (a2) is a novolac-type epoxy resin having a structural unit represented by the general formula (III).
[11] The photopolymerization initiator of component (B) is an alkylphenone photopolymerization initiator, an acylphosphine oxide photopolymerization initiator, a photopolymerization initiator having a thioxanthone skeleton, a titanocene photopolymerization initiator, and an oxime ester. The photosensitive resin composition according to any one of [1] to [10] above, which is at least one selected from the group consisting of photopolymerization initiators.
[12] The photopolymerization initiator of component (B) is at least one selected from the group consisting of an alkylphenone photopolymerization initiator, an acylphosphine oxide photopolymerization initiator, and an oxime ester photopolymerization initiator. , the photosensitive resin composition according to any one of [1] to [11] above.
[13] The photosensitive resin composition according to any one of [1] to [12] above, wherein the photopolymerization initiator of the component (B) is an acylphosphine oxide photopolymerization initiator.
[14] The photosensitive resin composition according to any one of [1] to [13] above, further containing (E) a pigment.
[15] The photosensitive resin composition according to any one of [1] to [14] above, further containing (F) an inorganic filler.
[16] A dry film comprising a carrier film and a photosensitive layer using the photosensitive resin composition according to any one of [1] to [15] above.
[17] A printed wiring board comprising a permanent mask resist formed from the photosensitive resin composition according to any one of [1] to [15] above.
[18] The printed wiring board according to [17] above, wherein the thickness of the permanent mask resist is 10 μm or more.
[19] A step of providing a photosensitive layer on a substrate using the photosensitive resin composition according to any one of [1] to [15] above or the dry film according to [16] above, the photosensitive layer A method for manufacturing a printed wiring board, comprising the steps of: forming a resist pattern using a resist pattern; and curing the resist pattern to form a permanent mask resist.

According to the present invention, it is possible to form a resist pattern in which undercuts in which the bottom portion of the resist pattern is gouged out and omissions in the upper portion of the resist pattern are less likely to occur, and the resist pattern contour has excellent linearity (that is, an excellent resist shape); , photosensitive resin compositions with excellent adhesion and fluidity to copper substrates, and improved reliability such as HAST resistance and crack resistance; production of dry films, printed wiring boards, and printed wiring boards using the same; method can be provided.

FIG. 2 is a schematic diagram showing a resist cross-sectional shape with excellent linearity of a resist pattern outline. FIG. 3 is a schematic diagram showing a cross-sectional shape of a resist with poor linearity of a resist pattern outline.

[Photosensitive resin composition]
The photosensitive resin composition according to the embodiment of the present invention (hereinafter sometimes simply referred to as the present embodiment) includes (A) an acid-modified vinyl group-containing epoxy resin, (B) a photopolymerization initiator, (C) It contains a polymerization inhibitor and (D) a photopolymerizable compound. In this specification, these components may be simply referred to as (A) component, (B) component, (C) component, (D) component, etc.
Since the photosensitive resin composition of this embodiment has the above-described structure, it is possible to improve the photocurability of the bottom part, so that undercuts where the bottom part of the resist pattern is gouged out and chipping of the top part of the resist pattern are less likely to occur. Since the exposure amount of ultraviolet irradiation is not increased, it is thought that a thick resist pattern with excellent linearity of the resist pattern contour can be formed. Furthermore, the photosensitive resin composition of the present embodiment has the above-mentioned specific configuration, so that it has excellent adhesion to a copper substrate and excellent fluidity. In addition, basic properties such as electrical insulation, soldering heat resistance, thermal shock resistance, solvent resistance, acid resistance, alkali resistance, HAST resistance, and crack resistance are required for photosensitive resin compositions used in printed wiring board manufacturing. It is thought that it will also be excellent.
Each component will be explained below.

<(A) Acid-modified vinyl group-containing epoxy resin>
The photosensitive resin composition of this embodiment contains an acid-modified vinyl group-containing epoxy resin as component (A). Component (A) is an epoxy resin modified with a vinyl group-containing organic acid, for example, a resin obtained by reacting an epoxy resin with a vinyl group-containing monocarboxylic acid containing a saturated group or an unsaturated group. Examples include epoxy resins produced by reacting polybasic acid anhydrides.

As component (A), for example, an acid-modified vinyl group-containing epoxy resin (A1) synthesized using a bisphenol novolac type epoxy resin (a1) (hereinafter sometimes referred to as component (a1)) (hereinafter referred to as component (a1)), (A1)), acid-modified vinyl group-containing synthesized using an epoxy resin (a2) other than the epoxy resin (a1) (hereinafter sometimes referred to as component (a2)) Examples include epoxy resin (A2) (hereinafter sometimes referred to as component (A2)), and these can be used alone or in combination. In addition, from the viewpoint of preventing undercuts and missing portions of the upper part of the resist, and improving the linearity of the resist pattern outline, adhesion to the copper substrate, and fluidity, component (A) is composed of component (a1). It may contain at least one component (A1) synthesized using component (A2) and at least one component (A2) synthesized using component (a2).

(Epoxy resin (a1))
As component (A), undercutting and chipping of the upper part of the resist are less likely to occur, and from the viewpoint of improving the linearity of the resist pattern outline, adhesion with the copper substrate, and fluidity, it also reduces warping of the thin film substrate. From the viewpoint of improving warpage (warpage reduction properties), thermal shock resistance, and resolution, it is preferable to contain component (A1) synthesized using component (a1). From the same viewpoint, component (a1) is preferably a bisphenol novolac type epoxy resin having a structural unit represented by the following general formula (I) or (II), and a bisphenol novolak type epoxy resin having a structural unit represented by the general formula (II). More preferred examples include bisphenol novolac type epoxy resins having units.

[Epoxy resin having a structural unit represented by general formula (I)]
One of the preferred embodiments of component (a1) is an epoxy resin having a structural unit represented by the following general formula (I).

In general formula (I), R ¹¹ represents a hydrogen atom or a methyl group, and Y ¹ and Y ² each independently represent a hydrogen atom or a glycidyl group. A plurality of R ^11s may be the same or different, and at least one of Y ¹ and Y ² represents a glycidyl group.

R ¹¹ is preferably a hydrogen atom from the viewpoint of preventing undercuts and missing portions of the upper part of the resist from occurring and improving the linearity and resolution of the resist pattern outline. Further, from the same viewpoint as this, and further from the viewpoint of improving thermal shock resistance and warpage reduction property, it is preferable that Y ¹ and Y ² are glycidyl groups.

The number of structural units of the structural unit represented by general formula (I) in one molecule of component (a1) is 1 or more, preferably 10 to 100, 15 to 80, or , 15 to 70 as appropriate. When the number of structural units is within the above range, it is possible to form a resist shape with improved linearity of the resist pattern outline, and the adhesion with the copper substrate, heat resistance, and electrical insulation properties are improved. Here, the number of structural units of the structural unit indicates an integer value when the component (a1) consists of a single type of molecule, and indicates a rational number that is an average value when it is an aggregate of multiple types of molecules. The same applies to the number of structural units below.

[Epoxy resin having a structural unit represented by general formula (II)]
Another preferred embodiment of component (a1) is an epoxy resin having a structural unit represented by the following general formula (II).

In general formula (II), R ¹² represents a hydrogen atom or a methyl group, and Y ³ and Y ⁴ each independently represent a hydrogen atom or a glycidyl group. A plurality of R ^12s may be the same or different, and at least one of Y ³ and Y ⁴ represents a glycidyl group.

R ¹² is preferably a hydrogen atom from the viewpoint of preventing undercuts and missing portions of the upper part of the resist from occurring and improving the linearity and resolution of the resist pattern outline.
Moreover, from the same viewpoint as this, and further from the viewpoint of improving thermal shock resistance and warpage reduction properties, Y ³ and Y ⁴ are preferably glycidyl groups.

The number of structural units of the structural unit represented by general formula (II) in one molecule of component (a1) is 1 or more, preferably 10 to 100, 15 to 80, or , 15 to 70 as appropriate. When the number of structural units is within the above range, it is possible to form a resist shape with improved linearity of the resist pattern outline, and the adhesion with the copper substrate, heat resistance, and electrical insulation properties are improved.

In general formula (II), those in which R ¹² is a hydrogen atom and Y ³ and Y ⁴ are glycidyl groups are, for example, EXA-7376 series (manufactured by DIC Corporation, trade name), and those in which R ¹² is methyl and those in which Y ³ and Y ⁴ are glycidyl groups are commercially available as EPON SU8 series (manufactured by Mitsubishi Chemical Corporation, trade name).

(Epoxy resin (a2))
Component (a2) is not particularly limited as long as it is an epoxy resin different from component (a1), but it reduces undercutting and chipping of the upper part of the resist, improves the linearity of the resist pattern outline, and improves adhesion to the copper substrate. , and from the viewpoint of improving fluidity and resolution, at least one selected from the group consisting of novolac type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and triphenolmethane type epoxy resin. It is preferable that it is one type.
As the novolak type epoxy resin, those having a structural unit represented by the following general formula (III) are preferably mentioned, and as the bisphenol A type epoxy resin or bisphenol F type epoxy resin, those having a structural unit represented by the following general formula (IV) are preferably mentioned. Preferred examples of the triphenolmethane type epoxy resin include those having a structural unit represented by the following general formula (V).

Component (a2) is a novolac type epoxy resin having a structural unit represented by general formula (III), and a bisphenol A type epoxy resin and bisphenol F type epoxy resin having a structural unit represented by general formula (IV). More preferably, it is at least one selected from the group consisting of: Bisphenol F type epoxy resin is preferred as the resin having a structural unit represented by general formula (IV).
In addition, from the viewpoint of achieving both photosensitive characteristics and insulation reliability, it is preferable to avoid using the component (A1), which uses the component (a1), and instead use the component (a2), which has a structural unit represented by the general formula (III). Preferably, it is a novolac type epoxy resin. Moreover, from the viewpoint of improving thermal shock resistance, warpage reduction property, and resolution, component (A) contains component (A1) and component (A2), and in particular, component (a1) contains the general formula ( A bisphenol novolac type epoxy resin containing the structural unit represented by II), and a bisphenol A type epoxy resin or bisphenol F type epoxy containing the structural unit represented by the general formula (IV) as component (a2). Particularly preferred is a combination of resins. Here, "not using component (A1)" indicates that it is substantially not contained, and the content of component (A1) is less than 5% by mass, 1% by mass of the total solid content of component (A), Indicates either less than 0.5% by mass or less than 0.5% by mass.

[Epoxy resin having a structural unit represented by general formula (III)]
Preferred examples of the component (a2) include novolak-type epoxy resins having a structural unit represented by the following general formula (III). Examples of novolak-type epoxy resins having such structural units include the following: A novolac type epoxy resin represented by the general formula (III') can be mentioned.

In general formulas (III) and (III'), R ¹³ represents a hydrogen atom or a methyl group, Y ⁵ represents a hydrogen atom or a glycidyl group, and the molar ratio of the hydrogen atom to the glycidyl group (hydrogen atom/glycidyl group) ) is 0/100 to 30/70. Further, in the general formula (III'), n ₁ is a number of 1 or more, a plurality of R ¹³ and Y ⁵ may be the same or different, and at least one of Y ⁵ represents a glycidyl group.

^R13 is preferably a hydrogen atom from the viewpoint of preventing undercuts and missing portions of the upper part of the resist from occurring and improving the linearity and resolution of the resist pattern outline.
Furthermore, in the component (a2) having the structural unit represented by the general formula (III) and in the component (a2) having the structural unit represented by the general formula (III'), Y ⁵ which is a hydrogen atom and a glycidyl group The molar ratio (hydrogen atom/glycidyl group) with Y ⁵ is from 0/100 to 30/3 from the viewpoint of preventing undercuts and missing portions of the upper part of the resist and improving the linearity and resolution of the resist pattern contour. 70, preferably 0/100 to 10/90. As can be seen from this molar ratio, at least one of Y ⁵ is a glycidyl group.

The number of structural units of the structural unit represented by the general formula (III) in one molecule of component (a2) and the number indicated by n ₁ in the general formula (III') are 1 or more. The number may be appropriately selected from 10 to 200, 30 to 150, or 30 to 100. When _n1 is within the above range, a resist shape with improved linearity of the resist pattern outline can be formed, and adhesion with the copper substrate, heat resistance, and electrical insulation properties are improved.

Examples of the novolak epoxy resin represented by the general formula (III) include phenol novolac epoxy resins and cresol novolak epoxy resins. These novolak-type epoxy resins can be obtained, for example, by reacting a phenol novolak resin, a cresol novolak resin, and epichlorohydrin by a known method.

Examples of the phenol novolac type epoxy resin or cresol novolac type epoxy resin represented by the general formula (III') include YDCN-701, YDCN-702, YDCN-703, YDCN-704, YDCN-704L, YDPN-638, YDPN-602 (product name manufactured by Nippon Steel Chemical & Materials Co., Ltd.), CEN-431, CEN-439 (product name manufactured by Dow Chemical Co., Ltd.), EOCN-120, EOCN-102S, EOCN-103S , EOCN-104S, EOCN-1012, EOCN-1025, EOCN-1027, BREN (all manufactured by Nippon Kayaku Co., Ltd., product names), EPN-1138, EPN-1235, EPN-1299 (all manufactured by BASF, Commercially available products include N-730, N-770, N-865, N-665, N-673, VH-4150, VH-4240 (all product names manufactured by DIC Corporation), etc. be.

[Epoxy resin having a structural unit represented by general formula (IV)]
As component (a2), bisphenol A type epoxy resin or bisphenol F type epoxy resin having a structural unit represented by the following general formula (IV) is further preferably mentioned, and as the epoxy resin having such a structural unit, For example, bisphenol A type epoxy resin or bisphenol F type epoxy resin represented by the general formula (IV') can be mentioned.

In general formulas (IV) and (IV'), R ¹⁴ represents a hydrogen atom or a methyl group, Y ⁶ represents a hydrogen atom or a glycidyl group, and the molar ratio of the hydrogen atom to the glycidyl group (hydrogen atom/glycidyl group) ) is 0/100 to 30/70. Furthermore, multiple R ^14s may be the same or different; in general formula (IV'), n ₂ represents a number of 1 or more; when n ₂ is 2 or more, multiple Y ^6s may be the same or different; and at least one Y ⁶ is a glycidyl group.

^R14 is preferably a hydrogen atom from the viewpoint of preventing undercuts and missing portions of the upper part of the resist from occurring and improving the linearity and resolution of the resist pattern outline.
Moreover, from the same viewpoint as this, and further from the viewpoint of improving thermal shock resistance and warpage reduction property, Y ⁶ is preferably a glycidyl group.
Furthermore, in the component (a2) having the structural unit represented by the general formula (IV) and in the component (a2) having the structural unit represented by the general formula (IV'), Y ⁶ which is a hydrogen atom and a glycidyl group The molar ratio (hydrogen atom/glycidyl group) with Y ⁶ is from 0/100 to 30/70, preferably from 0/100 to 10/90, from the viewpoint of improving thermal shock resistance and low warpage. In general formula (IV), at least one Y ⁶ is preferably a glycidyl group.

The number of structural units of the structural unit represented by general formula (IV) in one molecule of component (a2) and the number represented by n ₂ in general formula (IV') are 1 or more. The number may be appropriately selected from 10 to 100, 10 to 80, or 15 to 60. When _n2 is within the above range, a resist shape with improved linearity of the resist pattern outline can be formed, and adhesion with the copper substrate, heat resistance, and electrical insulation properties are improved.

Bisphenol A type epoxy resin or bisphenol F type epoxy resin represented by the general formula (IV') in which Y ⁶ is a glycidyl group is, for example, a bisphenol A or bisphenol F type epoxy resin represented by the following general formula (IV''). It can be obtained by reacting a hydroxyl group with epichlorohydrin.

In general formula (IV''), R ¹⁴ and n ₂ have the same meanings as in general formula (IV') above.

In order to promote the reaction between the hydroxyl group and epichlorohydrin, it is preferable to carry out the reaction at a reaction temperature of 50 to 120° C. in the presence of an alkali metal hydroxide in a polar organic solvent such as dimethylformamide, dimethylacetamide, or dimethyl sulfoxide. When the reaction temperature is within the above range, the reaction does not become too slow and side reactions can be suppressed.

Examples of the bisphenol A epoxy resin or bisphenol F epoxy resin represented by the general formula (IV') include jER807, 815, 825, 827, 828, 834, 1001, 1004, 1007 and 1009 (all of which are manufactured by Mitsubishi Chemical Co., Ltd., product name), DER-330, DER-301, DER-361 (manufactured by Dow Chemical Co., Ltd., product name), YD-8125, YDF-170, YDF-170, YDF-175S, YDF- 2001, YDF-2004, YDF-8170 (trade names, manufactured by Nippon Steel Chemical & Materials Co., Ltd.), etc. are commercially available.

[Epoxy resin having a structural unit represented by general formula (V)]
As component (a2), a triphenolmethane type epoxy resin having a structural unit represented by the following general formula (V) is further preferably mentioned, and as a triphenolmethane type epoxy resin having such a structural unit, For example, a triphenolmethane type epoxy resin represented by the general formula (V') is preferably mentioned.

In general formulas (V) and (V'), Y ⁷ represents a hydrogen atom or a glycidyl group, a plurality of Y ^7s may be the same or different, and at least one Y ⁷ is a glycidyl group. Further, in the general formula (V'), n ₃ represents a number of 1 or more.

In the component (a2) having the structural unit represented by the general formula (V) and in the component (a2) represented by the general formula (V'), Y ⁷ is a hydrogen atom and Y ⁷ is a glycidyl group. The molar ratio (hydrogen atom/glycidyl group) is preferably 0/100 to 30/3 from the viewpoint of preventing undercuts and missing portions of the upper part of the resist and improving the linearity and resolution of the resist pattern contour. 70, and may be appropriately selected from this range. As can be seen from this molar ratio, at least one of Y ⁷ is a glycidyl group.
The number of structural units of the structural unit represented by the general formula (V) in one molecule of component (a2) and the number represented by _n3 in the general formula (V') are 1 or more. The number may be appropriately selected from 10 to 100, 15 to 80, or 15 to 70. When _n3 is within the above range, a resist shape with improved linearity of the resist pattern outline can be formed, and adhesion with the copper substrate, heat resistance, and electrical insulation properties are improved.

As the triphenolmethane type epoxy resin represented by the general formula (V'), for example, FAE-2500, EPPN-501H, EPPN-502H (trade names, manufactured by Nippon Kayaku Co., Ltd.), etc. are commercially available. available.

The (A1) component and (A2) component are the (a1) component and (a2) component (hereinafter sometimes referred to as "(a) component") from the viewpoint of improving the linearity and resolution of the resist pattern outline. ) and a vinyl group-containing monocarboxylic acid (b) (hereinafter sometimes referred to as component (b)), resins (A1') and (A2') (hereinafter collectively referred to as "( A resin obtained by reacting saturated or unsaturated group-containing polybasic acid anhydride (c) (hereinafter sometimes referred to as component (c)) with component A'). It is preferable.

[Vinyl group-containing monocarboxylic acid (b)]
Component (b) includes, for example, acrylic acid, acrylic acid dimer, methacrylic acid, β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, α-cyanocinnamic acid, etc. Derivatives, half-ester compounds that are the reaction products of hydroxyl group-containing acrylates and dibasic acid anhydrides, vinyl group-containing monoglycidyl ethers, or half-esters that are the reaction products of vinyl group-containing monoglycidyl esters and dibasic acid anhydrides. Preferred examples include compounds.

The half-ester compound can be obtained, for example, by reacting a hydroxyl group-containing acrylate, a vinyl group-containing monoglycidyl ether, or a vinyl group-containing monoglycidyl ester with a dibasic acid anhydride in an equimolar ratio. These (b) components can be used alone or in combination.

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

Examples of the dibasic acid anhydride used in the synthesis of the half-ester compound include those containing a saturated group and those containing an unsaturated group. Specific examples of dibasic acid anhydrides include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride. acid, ethylhexahydrophthalic anhydride, itaconic anhydride, and the like.

In the reaction between component (a) and component (b), it is preferable to react at a ratio of 0.6 to 1.05 equivalents of component (b) to 1 equivalent of epoxy group in component (a). , it is more preferable to react at a ratio of 0.8 to 1.0 equivalents. By reacting at such a ratio, the photopolymerizability is improved, that is, the photosensitivity is increased, so that the linearity of the resist pattern outline is improved.

Component (a) and component (b) can be dissolved in an organic solvent and reacted.
Examples of organic solvents include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, and dipropylene. Glycol ethers such as glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; Esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, and carbitol acetate; Aliphatic hydrocarbons such as octane and decane Preferable examples include petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

Furthermore, it is preferable to use a catalyst to promote the reaction between component (a) and component (b). Examples of the catalyst include triethylamine, benzylmethylamine, methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, and the like.
The amount of the catalyst to be used is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 2 parts by weight, and even more preferably 0. It may be appropriately selected from .1 to 1 part by mass. When the above usage amount is used, the reaction between component (a) and component (b) is promoted.

Further, it is preferable to use a polymerization inhibitor for the purpose of preventing polymerization during the reaction. Examples of the polymerization inhibitor include hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, catechol, and pyrogallol.
From the viewpoint of improving the storage stability of the composition, the amount of the polymerization inhibitor used is preferably 0.01 to 1 part by mass, and more preferably 0.01 to 1 part by mass, per 100 parts by mass of components (a) and (b) in total. The amount may be appropriately selected from preferably 0.02 to 0.8 parts by mass, more preferably 0.04 to 0.5 parts by mass.

From the viewpoint of productivity, the reaction temperature between component (a) and component (b) is preferably selected from the range of 60 to 150°C, more preferably 80 to 120°C, and even more preferably 90 to 110°C. good.

In this way, component (A') obtained by reacting component (a) and component (b) is formed by a ring-opening addition reaction between the epoxy group of component (a) and the carboxyl group of component (b). It is presumed that it has a hydroxyl group.
By further reacting the component (A') obtained above with the component (c) containing a saturated or unsaturated group, the hydroxyl group of the component (A') (the hydroxyl group originally present in the component (a) is also removed). It is presumed that the acid-modified vinyl group-containing epoxy resin is obtained by half-esterifying the acid anhydride group of component (c) and the acid anhydride group of component (c).

[Polybasic acid anhydride (c)]
As component (c), those containing saturated groups and those containing unsaturated groups can be used. Specific examples of component (c) include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride. , ethylhexahydrophthalic anhydride, itaconic anhydride, and the like. Among these, from the viewpoint of obtaining a photosensitive resin composition capable of forming a pattern with excellent resolution, tetrahydrophthalic anhydride is preferred.

In the reaction between component (A') and component (c), for example, by reacting 0.1 to 1.0 equivalent of component (c) with respect to 1 equivalent of hydroxyl group in component (A'), acid The acid value of the modified vinyl group-containing epoxy resin can be adjusted.

The acid value of component (A) is preferably 30 to 150 mgKOH/g, more preferably 40 to 120 mgKOH/g, and still more preferably 50 to 100 mgKOH/g. When the acid value is 30 mgKOH/g or more, the photosensitive resin composition has excellent solubility in a dilute alkaline solution, and when it is 150 mgKOH/g or less, the electrical properties of the cured film are improved.

From the viewpoint of productivity, the reaction temperature between component (A') and component (c) is preferably selected from the range of 50 to 150°C, more preferably 60 to 120°C, and even more preferably 70 to 100°C. Bye.

Further, if necessary, as component (a), for example, a part of hydrogenated bisphenol A epoxy resin can be used in combination. Furthermore, as component (A), a styrene-maleic acid resin such as a hydroxyethyl (meth)acrylate modified product of a styrene-maleic anhydride copolymer can also be used in part.

(Molecular weight of component (A))
The weight average molecular weight of component (A) is preferably 3,000 to 30,000, more preferably 4,000 to 25,000, and still more preferably 5,000 to 18,000. Within the above range, it is possible to form a resist shape with improved linearity of the resist pattern outline, and the adhesion with the copper substrate, heat resistance, and electrical insulation properties are improved. Here, the weight average molecular weight is a polystyrene equivalent weight average molecular weight measured by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent. More specifically, for example, the weight average molecular weight can be determined by measuring with the following GPC measurement device and measurement conditions and converting it using a standard polystyrene calibration curve. In addition, to create a calibration curve, a set of 5 samples ("PStQuick MP-H" and "PStQuick B", manufactured by Tosoh Corporation) is used as standard polystyrene.
(GPC measurement device)
GPC device: High-speed GPC device “HCL-8320GPC”, detector is differential refractometer or UV, manufactured by Tosoh Corporation Column: Column TSKgel SuperMultipore HZ-H (column length: 15 cm, column inner diameter: 4.6 mm), manufactured by Tosoh Corporation Manufactured by the company (measurement conditions)
Solvent: Tetrahydrofuran (THF)
Measurement temperature: 40℃
Flow rate: 0.35ml/min Sample concentration: 10mg/THF5ml
Injection volume: 20μl

(Content of (A) component)
From the viewpoint of improving the heat resistance, electrical properties, and chemical resistance of the coating film, the content of component (A) in the photosensitive resin composition is preferably 20% based on the total solid content of the photosensitive resin composition. It may be appropriately selected from the range of 80% by mass, more preferably 30% to 70% by mass, even more preferably 30% to 50% by mass. In this specification, "solid content" refers to non-volatile content excluding volatile substances such as water and diluent contained in the photosensitive resin composition, and is evaporated when the resin composition is dried. , refers to components that remain without volatilization, and also includes those that are liquid, syrupy, and waxy at room temperature around 25°C.

(Total content of component (A1) and component (A2) in component (A))
When using a combination of components (A1) and (A2) as component (A), the total content of components (A1) and (A2) in component (A) is determined by the linearity of the resist pattern outline. From the viewpoint of forming a resist shape with improved electroless plating resistance and soldering heat resistance, preferably 80 to 100% by mass, more preferably 90 to 100% by mass, and even more preferably 95 to 100% by mass. It may be selected as appropriate from the range. Moreover, when using the component (A1) and the component (A2) alone, they may be selected as appropriate from the above range.

(Mass ratio of component (A1) to component (A2))
When using a combination of components (A1) and (A2) as component (A), the mass ratio (A1/A2) is such that a resist shape with improved linearity of the resist pattern contour can be formed, and it is electroless resistant. From the viewpoint of improving plating properties and soldering heat resistance, it is preferably selected from the range of 20/80 to 90/10, more preferably 20/80 to 80/20, and still more preferably 30/70 to 70/30. Bye.

<(B) Photopolymerization initiator>
Component (B) used in this embodiment is not particularly limited as long as it can polymerize the photopolymerizable compound of component (D) described below, and is appropriately selected from commonly used photopolymerization initiators. can do. For example, conventionally known photopolymerization initiators such as alkylphenone photopolymerization initiators, acylphosphine oxide photopolymerization initiators, photopolymerization initiators having a thioxanthone skeleton, titanocene photopolymerization initiators, oxime ester photopolymerization initiators, etc. These photopolymerization initiators may be used alone or in combination. Among these, alkylphenone-based photopolymerization initiators, acylphosphine oxide-based photopolymerization initiators, and acylphosphine oxide-based photopolymerization initiators are preferred from the viewpoint of forming a resist shape with improved linearity of the resist pattern outline and improving electroless plating resistance and soldering heat resistance. As an initiator, an oxime ester type photopolymerization initiator is preferably used, and an acylphosphine oxide type photopolymerization initiator is particularly preferably used.

Examples of alkylphenone photopolymerization initiators include 2-methyl-1-(4-methylthiophenyl)-2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl) )-butanone-1,2,2-dimethoxy-1,2-diphenylethan-1-one and other benzyl dimethyl ketal photopolymerization initiators; 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl -1-phenyl-propan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4 -[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one and other α-hydroxyalkylphenone photopolymerization initiators; 2-methyl-1-[ 4-(Methylthio)phenyl]-2-morpholinopropanone-1,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-(dimethylamino)-2-[ (4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, N,N-dimethylaminoacetophenone and other α-aminoacetophenone photopolymerization initiators, etc. A single species or a combination of multiple species can be used.

The acylphosphine oxide-based photopolymerization initiator is not particularly limited as long as it is a compound having an acylphosphine oxide group (=P(=O)-C(=O)- group); for example, (2,6-dimethoxy benzoyl)-2,4,4-pentylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl-2,4,6-trimethylbenzoylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl) Phenylphosphine oxide, (2,5-dihydroxyphenyl)diphenylphosphine oxide, (p-hydroxyphenyl)diphenylphosphine oxide, bis(p-hydroxyphenyl)phenylphosphine oxide, and tris(p-hydroxyphenyl)phosphine oxide, bis( Examples include 2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, which can be used alone or in combination.

Examples of the photopolymerization initiator having a thioxanthone skeleton include thioxanthone, 2,4-diethylthioxanthene-9-one, 2-isopropylthioxanthone, 2-chlorothioxanthone, and the like. Can be used in combination.

Examples of the titanocene photopolymerization initiator include bis(η-5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl ) titanium, etc., and can be used alone or in combination.

Examples of oxime ester photopolymerization initiators include ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(0-acetyloxime), and benzoin. , benzoins such as benzoin methyl ether and benzoin isopropyl ether, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone , 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-methyl-1-[4-(methylthio)phenyl)-2-morpholino-propanon-1-one, N, Aromatic ketones such as N-dimethylaminoacetophenone, anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone, acetophenone dimethyl Ketals such as ketal, benzyl dimethyl ketal, benzophenones such as benzophenone, methylbenzophenone, 4,4'-dichlorobenzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 9-phenylacridine, 1,7-bis(9 , 9'-acridinyl)heptane, 2,4,5-triarylimidazole dimer or derivatives thereof, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, etc., and these may be used alone or Multiple types can be used in combination.

(Content of component (B))
The content of the photopolymerization initiator (B) component is determined based on the total solid content of the photosensitive resin composition, from the viewpoint of obtaining a photosensitive resin composition that can form a resist shape with improved linearity of the resist pattern outline. , 0.2 to 15% by mass, 0.4 to 5% by mass, or 0.6 to 1% by mass. Further, when the content of component (B) is 0.2% by mass or more, the exposed area becomes difficult to dissolve during development, and when the content is 15% by mass or less, a decrease in heat resistance can be suppressed.

<(C) Polymerization inhibitor>
The photosensitive resin composition of the present invention contains a polymerization inhibitor together with a photopolymerization initiator as component (B).
Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol, phenothiazine, and 4,4'-butylidene-bis(6-tert-butyl-m-cresol).The polymerization inhibitor includes: More preferably, it is a phenolic antioxidant.
The polymerization inhibitor preferably has a melting point of 100° C. or higher, more preferably 125° C. or higher, in order to suppress volatilization during heating after the development step is completed.

(Content of polymerization inhibitor which is component (C))
The content of the polymerization inhibitor as component (C) is preferably 0.001 to 20% by mass, more preferably 0.01 to 2% by mass, and more preferably 0.001 to 20% by mass, based on the total solid content in the photosensitive resin composition. Preferably, it may be appropriately selected from the range of 0.01 to 0.1% by mass. When the content is 0.001% by mass or more, the tendency of exposed areas to dissolve during development can be suppressed due to low photosensitivity, and when it is 20% by mass or less, a decrease in heat resistance can be suppressed.

<(D) Photopolymerizable compound>
The photopolymerizable compound of component (D) has a functional group exhibiting photopolymerizability, such as a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadimide group, and a (meth)acryloyl group. There is no particular restriction as long as the compound has an ethylenically unsaturated group such as, but from the viewpoint of reactivity, a compound having a (meth)acryloyl group is preferable.
In addition, in this specification, a (meth)acryloyl group means an acryloyl group or a methacryloyl group, and (meth)acrylate means an acrylate or a methacrylate.

Component (D) includes, for example, hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate, glycols such as ethylene glycol, methoxytetraethylene glycol, and polyethylene glycol. Mono- or di(meth)acrylates, (meth)acrylamides such as N,N-dimethyl(meth)acrylamide, N-methylol(meth)acrylamide, aminoalkyl(s) such as N,N-dimethylaminoethyl(meth)acrylate, etc. Polyvalent (meth)acrylates, polyhydric alcohols such as hexanediol, trimethylolpropane, pentaerythritol, ditrimethylolpropane, dipentaerythritol, tris-hydroxyethyl isocyanurate, or their ethylene oxide or propylene oxide adducts Acrylates, (meth)acrylates of ethylene oxide or propylene oxide adducts of phenols such as phenoxyethyl (meth)acrylate, polyethoxydi(meth)acrylate of bisphenol A, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, Preferred examples include glycidyl ether (meth)acrylates such as glycidyl isocyanurate, and melamine (meth)acrylate. These (D) components can be used alone or in combination.
Further, it may contain polyhydric (meth)acrylates of the polyhydric alcohols or their ethylene oxide or propylene oxide adducts.

(Content of component (D))
The content of component (D) is preferably from 2 to 50% by mass, more preferably from 3 to 20% by mass, even more preferably from 3 to 10% by mass, based on the total solid content in the photosensitive resin composition. Just choose. When the content is 2% by mass or more, the tendency of exposed areas to dissolve during development due to low photosensitivity can be suppressed, and when the content is 50% by mass or less, a decrease in heat resistance can be suppressed.

<(E) Pigment>
The photosensitive resin composition of this embodiment may further contain a pigment (E), if necessary. Component (E) is preferably used depending on the desired color when hiding wiring or the like. As component (E), a coloring agent that develops a desired color may be appropriately selected and used, such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, and naphthalene black. Preferred examples include known colorants such as.

(Content of (E) component)
When using component (E), the content of component (E) is preferably 0.1 to 5% by mass, based on the total solid content in the photosensitive resin composition, from the viewpoint of further hiding the wiring. It may be appropriately selected from 0.1 to 3% by mass, more preferably 0.5 to 2% by mass.

<(F) Inorganic filler>
In the photosensitive resin composition of the present embodiment, an inorganic filler (F) can be used as necessary for the purpose of further improving various properties such as adhesion and coating hardness.
As the component (F), for example, silica (SiO ₂ ), alumina (Al ₂ O ₃ ), zirconia (ZrO ₂ ), talc (3MgO・4SiO ₂・H ₂ O), aluminum hydroxide (Al(OH) ₃ ), calcium carbonate (CaCO ₃ ), barium sulfate (BaSO ₄ ), calcium sulfate (CaSO ₄ ), zinc oxide (ZnO), magnesium titanate (MgO・TiO ₂ ), carbon (C), etc. can be used. . These inorganic fillers can be used alone or in combination.

The average particle size of component (F) may be appropriately selected from preferably 0.1 to 20 μm, more preferably 0.1 to 10 μm, even more preferably 0.1 to 5 μm, and still more preferably 0.1 to 1 μm. . When the average particle size is 20 μm or less, deterioration in insulation reliability can be further suppressed. Here, the average particle size of component (F) can be measured using, for example, a dynamic light scattering type Nanotrac particle size distribution meter "UPA-EX150" (manufactured by Nikkiso Co., Ltd., trade name) and a laser diffraction scattering type Microtrac particle size distribution meter "UPA-EX150" (manufactured by Nikkiso Co., Ltd., trade name). MT-3100 (manufactured by Nikkiso Co., Ltd., trade name).

Among component (F), it is preferable to include silica from the viewpoint of improving heat resistance, and it is preferable to include silica, which improves soldering heat resistance, crack resistance (thermal shock resistance), and adhesion between the underfill material and the cured film after the PCT test. From the viewpoint of improving strength, it is preferable that barium sulfate is included, and silica and barium sulfate may be included in combination. Further, from the viewpoint of improving the agglomeration prevention effect, the inorganic filler may be appropriately selected from one whose surface is treated with alumina or an organic silane compound.

The elemental composition of aluminum on the surface of the inorganic filler surface-treated with alumina or an organic silane compound is preferably 0.5 to 10 atomic %, more preferably 1 to 5 atomic %, and even more preferably 1.5 to 3 atomic %. It may be appropriately selected from .5 atomic %. In addition, the elemental composition of silicon on the surface of the inorganic filler surface-treated with an organic silane compound is preferably 0.5 to 10 atomic %, more preferably 1 to 5 atomic %, and even more preferably 1.5 to 3 atomic %. It may be appropriately selected from .5 atomic %. Further, the elemental composition of carbon on the surface of the inorganic filler surface-treated with an organic silane compound is preferably from 10 to 30 atom%, more preferably from 15 to 25 atom%, and still more preferably from 18 to 23 atom%. Just choose. These elemental compositions can be measured using XPS (X-ray Photoelectron Spectroscopy).

For example, barium sulfate whose surface is treated with alumina or an organic silane compound is commercially available as NanoFine BFN40DC (manufactured by Nippon Solvay Co., Ltd., trade name). available at.

(Content of (F) component)
When component (F) is used, its content is preferably 10 to 80% by mass, more preferably 15 to 70% by mass, even more preferably 20 to 50% by mass, based on the total solid content of the photosensitive resin composition. It may be appropriately selected from 25 to 40% by mass, more preferably 25 to 40% by mass. Within the above range, the cured product strength, heat resistance, insulation reliability, thermal shock resistance, resolution, etc. of the photosensitive resin composition can be further improved.

When using silica as component (F), the content of silica is preferably 5 to 60% by mass, more preferably 15 to 55% by mass, even more preferably It may be appropriately selected from 15 to 50% by mass. Further, when barium sulfate is used as the component (F), the content of barium sulfate is preferably 5 to 30% by mass, more preferably 5 to 25% by mass, based on the total solid content of the photosensitive resin composition. , more preferably 5 to 20% by mass. Within the above range, the solder heat resistance and the adhesive strength between the underfill material and the cured film after the PCT test can be further improved.

<Diluent>
The photosensitive resin composition of this embodiment can use a diluent if necessary. As the diluent, for example, an organic solvent can be used. Examples of organic solvents include ketones such as methyl ethyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene, methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, and dipropylene. Glycol ethers such as glycol monoethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether, esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, carbitol acetate, aliphatic hydrocarbons such as octane, decane, etc. , petroleum-based solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

The amount of diluent used is such that the total solid content in the photosensitive resin composition is preferably 50 to 90% by mass, more preferably 60 to 80% by mass, and even more preferably 65 to 75% by mass. You can select as appropriate. That is, when a diluent is used, the content of the diluent in the photosensitive resin composition is preferably selected from 10 to 50% by mass, more preferably 20 to 40% by mass, and even more preferably 25 to 35% by mass. do it. By setting it within the above range, the coating properties of the photosensitive resin composition are improved, and it becomes possible to form a pattern with higher definition.

<(G) Curing agent>
The photosensitive resin composition of this embodiment may contain (G) a curing agent, if necessary. Component (G) is a compound that itself is cured by heat, ultraviolet rays, etc., or a carboxyl group or hydroxyl group of component (A), which is a photocurable component in the photosensitive resin composition of this embodiment, and heat, Examples include compounds that react and cure with ultraviolet light and the like. By using a curing agent, the heat resistance, adhesion, chemical resistance, etc. of the final cured film can be improved.

Examples of the curing agent for component (G) include thermosetting compounds, such as epoxy compounds, melamine compounds, and oxazoline compounds. Examples of epoxy compounds include bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, brominated bisphenol A epoxy resin, novolak epoxy resin, bisphenol S epoxy resin, and biphenyl epoxy resin. Alternatively, examples include heterocyclic epoxy resins such as triglycidyl isocyanurate, bixylenol type epoxy resins, and the like.
Examples of the melamine compound include triaminotriazine, hexamethoxymelamine, hexabutoxylated melamine, and the like.
Among these, from the viewpoint of further improving the heat resistance of the cured film, it is preferable to include an epoxy compound (epoxy resin), and it is more preferable to use an epoxy compound and a block isocyanate in combination.

As the blocked isocyanate, an addition reaction product of a polyisocyanate compound and an isocyanate blocking agent is used. Examples of the polyisocyanate compound include tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, naphthylene diisocyanate, bis(isocyanatomethyl)cyclohexane, tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, etc. Polyisocyanate compounds, as well as their adducts, biurets, isocyanurates, and the like.

Component (G) may be used alone or in combination. When component (G) is used, its content is preferably 2 to 40% by mass, more preferably 3 to 30% by mass, and even more preferably 5 to 20% by mass, based on the total solid content of the photosensitive resin composition. % may be selected as appropriate. By keeping it within the above range, the heat resistance of the cured film to be formed can be further improved while maintaining good developability.

<(H) Epoxy resin curing agent>
In addition, (H) an epoxy resin curing agent is added to the photosensitive resin composition of this embodiment, if necessary, for the purpose of further improving various properties such as heat resistance, adhesion, and chemical resistance of the final cured film. Can be used together.
Specific examples of such an epoxy resin curing agent as component (H) include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenylimidazole, - Imidazole derivatives such as phenyl-4-methyl-5-hydroxymethylimidazole: Guanamines such as acetoguanamine and benzoguanamine: diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, Polyamines such as melamine and polybasic hydrazide: Organic acid salts or epoxy adducts of these: Amine complexes of boron trifluoride: Ethyldiamino-s-triazine, 2,4-diamino-s-triazine, 2,4-diamino- Examples include triazine derivatives such as 6-xylyl-s-triazine.

The epoxy resin curing agent as component (H) can be used alone or in combination. When used, the content of the epoxy resin curing agent in the photosensitive resin composition should be adjusted to improve reliability. From this point of view, it may be appropriately selected from preferably 0.01 to 20% by mass, more preferably 0.1 to 10% by mass, based on the total solid content of the photosensitive resin composition.

<(I) Elastomer>
The photosensitive resin composition of this embodiment can contain (I) an elastomer. Component (I) can be suitably used especially when the photosensitive resin composition of this embodiment is used for a semiconductor package substrate. By adding component (I), it is possible to suppress a decrease in flexibility and adhesive strength caused by distortion (internal stress) inside the resin due to curing shrinkage of component (A). That is, the flexibility, adhesive strength, etc. of the cured film formed from the photosensitive resin composition can be improved.

Examples of the component (I) include styrene elastomers, olefin elastomers, urethane elastomers, polyester elastomers, polyamide elastomers, acrylic elastomers, and silicone elastomers. These elastomers are composed of hard segment components and soft segment components, with the former generally contributing to heat resistance and strength, and the latter contributing to flexibility and toughness.

Urethane elastomers consist of a structural unit consisting of a hard segment made of low-molecular glycol and diisocyanate, and a soft segment made of polymeric (long-chain) diol and diisocyanate. Specific examples of polymeric (long-chain) diols include polypropylene. Glycol, polytetramethylene oxide, poly(1,4-butylene adipate), poly(ethylene-1,4-butylene adipate), polycaprolactone, poly(1,6-hexylene carbonate), poly(1,6-hexylene) - neopentylene adipate), etc.
The number average molecular weight of the polymeric (long chain) diol is preferably 500 to 10,000. In addition to ethylene glycol, short chain diols such as propylene glycol, 1,4-butanediol, and bisphenol A can be used, and the number average molecular weight of the short chain diol is preferably 48 to 500. As specific examples of urethane elastomers, PANDEX T-2185, T-2983N (manufactured by DIC Corporation), Miractran E790 (manufactured by Nippon Miractran Corporation), etc. are commercially available.

Examples of polyester elastomers include those obtained by polycondensing dicarboxylic acids or derivatives thereof and diol compounds or derivatives thereof. Specific examples of dicarboxylic acids include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalene dicarboxylic acid; aromatic dicarboxylic acids in which the hydrogen atoms of these aromatic nuclei are substituted with methyl groups, ethyl groups, phenyl groups, etc., and adipine. Examples include aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as sebacic acid and dodecanedicarboxylic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid.
These compounds can be used alone or in combination.

Specific examples of diol compounds include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, and 1,4-cyclohexanediol. and alicyclic diols, or dihydric phenols represented by the following general formula (VI).

In the general formula (VI), Y is a divalent group selected from the group consisting of an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, -O-, -S-, and -SO ₂ -. Indicates that benzene rings are bonded directly to each other by a functional group, R ¹ and R ² each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 12 carbon atoms, and l and m each independently represents an integer from 0 to 4, and p represents 0 or 1. The alkylene group and cycloalkylene group may be linear or branched, and may be substituted with a halogen atom, an alkyl group, an aryl group, an aralkyl group, an amino group, an amide group, an alkoxy group, or the like.

Specific examples of the dihydric phenol represented by general formula (VI) include bisphenol A, bis-(4-hydroxyphenyl)methane, bis-(4-hydroxy-3-methylphenyl)propane, and resorcinol. Can be mentioned. These compounds can be used alone or in combination.
Furthermore, a multi-block copolymer can be used in which an aromatic polyester (eg, polybutylene terephthalate) portion is used as a hard segment component and an aliphatic polyester (eg, polytetramethylene glycol) portion is used as a soft segment component. There are various grades depending on the type, ratio, and molecular weight of hard and soft segments. Specifically, Hytrel (manufactured by DuPont-Toray Co., Ltd., "Hytrel" is a registered trademark), Pelprene (manufactured by Toyobo Co., Ltd., "Pelprene" is a registered trademark), and Espel (manufactured by Hitachi Chemical Co., Ltd., "Espel" is a registered trademark). Trademark) etc. are commercially available.

Examples of acrylic elastomers include those synthesized mainly from acrylic esters such as ethyl acrylate, butyl acrylate, methoxyethyl acrylate, and ethoxyethyl acrylate. Further, as the crosslinking point monomer, glycidyl methacrylate, allyl glycidyl ether, etc. may be used. Furthermore, acrylonitrile and ethylene can also be copolymerized. Specific examples include acrylonitrile-butyl acrylate copolymer, acrylonitrile-butyl acrylate-ethyl acrylate copolymer, acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer, and the like.

Furthermore, in addition to the above-mentioned thermoplastic elastomer, a rubber-modified epoxy resin can be used. Rubber-modified epoxy resins include, for example, bisphenol F-type epoxy resins, bisphenol A-type epoxy resins, salicylaldehyde-type epoxy resins, phenol novolac-type epoxy resins, or cresol novolac-type epoxy resins in which both part or all of the epoxy groups are combined. It can be obtained by modification with terminal carboxylic acid-modified butadiene-acrylonitrile rubber, terminal amino-modified silicone rubber, etc. Among these elastomers, from the viewpoint of shear adhesion, butadiene-acrylonitrile copolymer modified with carboxyl groups at both ends, and Espel (manufactured by Hitachi Chemical Co., Ltd., trade name: Espel 1612, 1620), which is a polyester elastomer having hydroxyl groups, are preferred. is preferred.

When component (I) is used, its content is preferably 2 to 40 parts by mass, more preferably 4 to 30 parts by mass, even more preferably 10 parts by mass, per 100 parts by mass of component (A) (solid content). It may be appropriately selected from 15 to 22 parts by mass, more preferably 15 to 22 parts by mass. By setting it within the above range, the elastic modulus of the cured film in the high temperature region becomes lower, and the unexposed areas become more easily eluted by the developer.

<Other additives>
The photosensitive resin composition of this embodiment may optionally contain various known and commonly used thickeners such as bentone and montmorillonite, silicone-based, fluorine-based, and vinyl resin-based antifoaming agents, and silane coupling agents. Additives can be used. Furthermore, flame retardants such as brominated epoxy compounds, acid-modified brominated epoxy compounds, antimony compounds, phosphate compounds of phosphorous compounds, aromatic condensed phosphoric esters, halogen-containing condensed phosphoric esters, etc. can be used.
Furthermore, the photosensitive resin composition of the present embodiment may further include a triazine compound such as melamine as an adhesion-imparting material, if necessary.

The photosensitive resin composition of this embodiment can be obtained by uniformly kneading and mixing the ingredients using a roll mill, bead mill, etc.

[Dry film]
The dry film of this embodiment has a carrier film and a photosensitive layer using the photosensitive resin composition of this embodiment.
The thickness of the photosensitive layer is not particularly limited, but may be appropriately selected from preferably 10 to 50 μm, more preferably 15 to 40 μm, and even more preferably 20 to 30 μm.

The dry film of this embodiment can be produced by, for example, applying and drying the photosensitive resin composition of this embodiment onto a carrier film by a known method such as reverse roll coating, gravure roll coating, comma coating, curtain coating, etc. , a photosensitive layer can be formed and manufactured.
Examples of the carrier film include polyesters such as polyethylene terephthalate and polybutylene terephthalate, and polyolefins such as polypropylene and polyethylene. The thickness of the carrier film is not particularly limited, but may be appropriately selected from the range of 5 to 100 μm. Further, in the dry film of the present embodiment, a protective layer can be laminated on the surface of the photosensitive layer opposite to the surface in contact with the carrier film. As the protective layer, for example, a polymer film such as polyethylene or polypropylene may be used. Further, a polymer film similar to the carrier film described above may be used, or a different polymer film may be used.
The coating film can be dried using hot air drying, a dryer using far infrared rays, or near infrared rays, and the drying temperature is, for example, preferably 60 to 120°C, more preferably 70 to 110°C, More preferably, the temperature may be appropriately selected from 80 to 100°C. Further, the drying time may be appropriately selected, for example, preferably from 1 to 60 minutes, more preferably from 2 to 30 minutes, and even more preferably from 5 to 20 minutes.

[Printed wiring board]
The printed wiring board of this embodiment includes a permanent mask resist formed from the photosensitive resin composition of this embodiment.
Since the printed wiring board of this embodiment includes a permanent mask resist formed from the photosensitive resin composition of this embodiment, the printed wiring board can be patterned without creating an undercut where the bottom part is gouged or missing the upper part of the resist. The line width at the middle part (center) and the deepest part (bottom) of the cross section is not larger than the line width at the surface, so it is possible to create a pattern with good linearity of the pattern outline, excellent resist shape, and excellent resolution. have In addition, this permanent mask resist has a pattern with excellent formation stability in the size of the hole diameter and the pitch between the holes, which have become finer due to the miniaturization and higher performance of electronic devices in recent years.

[Manufacturing method of printed wiring board]
The method for manufacturing a printed wiring board of this embodiment includes the steps of providing a photosensitive layer on a substrate using the photosensitive resin composition of this embodiment or the dry film of this embodiment, and forming a resist pattern using the photosensitive layer. and curing the resist pattern to form a permanent mask resist.
Specifically, for example, it can be manufactured as follows.
First, a metal-clad laminate such as a copper-clad laminate is coated with a thickness of, for example, 10 to 200 μm, preferably 15 to 150 μm, by a method such as a screen printing method, a spray method, a roll coating method, a curtain coating method, or an electrostatic coating method. , more preferably from 20 to 100 μm, and even more preferably from 23 to 50 μm. Next, the coating film is preferably dried at 60 to 110° C., or a protective layer is applied. A photosensitive layer is provided on the substrate by thermally laminating the peeled dry film of this embodiment onto the substrate using a laminator.
Next, a negative film is brought into direct contact with the photosensitive layer (or non-contacted through a transparent film such as a carrier film), and active light is applied to the photosensitive layer at a rate of, for example, 10 to 2,000 mJ/cm ² , preferably 100 to 100 mJ/cm 2 . , 500 mJ/cm ² , more preferably 300 to 1,000 mJ/cm ² , and then the unexposed areas are dissolved and removed (developed) with a dilute alkaline aqueous solution to form a resist pattern. Examples of the active light used include electron beams, ultraviolet rays, and X-rays, with ultraviolet rays being preferred. Further, as a light source, a low pressure mercury lamp, a high pressure mercury lamp, an ultra-high pressure mercury lamp, a halogen lamp, etc. can be used. A resist pattern may be formed by direct exposure using a direct exposure machine instead of a negative film.
Next, the exposed portions of the photosensitive layer are sufficiently cured by at least one of post-exposure (ultraviolet light exposure) and post-heating to form a permanent mask resist.
The exposure amount for post-exposure may be appropriately selected from preferably 100 to 5,000 mJ/cm ² , more preferably 500 to 2,000 mJ/cm ² , and even more preferably 700 to 1,500 J/cm ² .
The heating temperature for post-heating may be appropriately selected from preferably 100 to 200°C, more preferably 120 to 180°C, and even more preferably 135 to 165°C.
The heating time for post-heating may be appropriately selected from preferably 5 minutes to 12 hours, more preferably 10 minutes to 6 hours, and even more preferably 30 minutes to 2 hours.
The thickness of the permanent mask resist thus formed is preferably 10 μm or more, more preferably 10 to 100 μm, and even more preferably 10 to 50 μm, from the viewpoint of insulation and resolution.
Thereafter, wiring is formed by etching, and a printed wiring board is produced.

Hereinafter, the objects and advantages of this embodiment will be explained in more detail based on Examples and Comparative Examples, but this embodiment is not limited to the following Examples.

(Synthesis example 1)
Bisphenol F novolak type epoxy resin (a) (EXA-7376, manufactured by DIC Corporation, bisphenol F novolak containing a structural unit in general formula (II) where Y ³ and Y ⁴ are glycidyl groups and R ¹² is a hydrogen atom) Type epoxy resin, epoxy equivalent: 186) 350 parts by mass, 70 parts by mass of acrylic acid (b), 0.5 parts by mass of methylhydroquinone, and 120 parts by mass of carbitol acetate were charged and reacted by heating to 90°C and stirring. The mixture was completely dissolved. Next, the obtained solution was cooled to 60°C, 2 parts by mass of triphenylphosphine was added, heated to 100°C, and reacted until the acid value of the solution became 1 mgKOH/g or less, and the (A1') component A solution containing was obtained. 98 parts by mass of tetrahydrophthalic anhydride (THPAC) (c) and 85 parts by mass of carbitol acetate were added to the solution after the reaction, heated to 80° C., and reacted for 6 hours. Thereafter, the mixture was cooled to room temperature (25° C.) to obtain a THPAC-modified bisphenol F novolak type epoxy acrylate as component (A1) having a solid content concentration of 73% by mass.

(Synthesis example 2)
In a flask equipped with a stirrer, a reflux condenser, and a thermometer, add a bisphenol F-type epoxy resin (bisphenol F-type epoxy resin containing a structural unit in which Y ⁶ is a hydrogen atom and R ¹⁴ is a hydrogen atom in the general formula (IV)). Resin) (a) (epoxy equivalent: 526) 1,052 parts by mass, 144 parts by mass of acrylic acid (b), 1 part by mass of methylhydroquinone, 850 parts by mass of carbitol acetate and 100 parts by mass of solvent naphtha were charged, and the mixture was heated at 70°C. The mixture was dissolved by heating and stirring. Next, the solution was cooled to 50°C, 2 parts by mass of triphenylphosphine and 75 parts by mass of solvent naphtha were added, heated to 100°C, and reacted until the solid content acid value became 1 mgKOH/g or less, (A2') A solution containing the ingredients was obtained. Next, the obtained solution was cooled to 50°C, 745 parts by mass of tetrahydrophthalic anhydride (THPAC) (c), 75 parts by mass of carbitol acetate, and 75 parts by mass of solvent naphtha were charged, and heated to 80°C. The reaction was allowed to proceed for 6 hours. Thereafter, the mixture was cooled to room temperature to obtain a THPAC-modified bisphenol F type epoxy acrylate as component (A2) having a solid acid value of 80 mgKOH/g and a solid content of 62% by mass.

(Examples 1 to 10, Comparative Examples 1 to 5)
A composition was blended according to the composition shown in Table 1 and kneaded in a three-roll mill to prepare a photosensitive resin composition. Carbitol acetate was added so that the solid content concentration was 70% by mass to obtain a photosensitive resin composition.

The details of each material in Table 1 are as follows.
(A) Acid-modified vinyl group-containing epoxy resin A1; Acid-modified vinyl group-containing epoxy resin (I) obtained in Synthesis Example 1 (THPAC-modified bisphenol F novolak type epoxy acrylate)
・A2; Acid-modified vinyl group-containing epoxy resin (II) obtained in Synthesis Example 2 (THPAC-modified bisphenol F type epoxy acrylate)
(B) Photopolymerization initiator/Irgacure 907: 2-methyl-[4-(methylthio)phenyl]morpholino-1-propanone (manufactured by BASF, trade name) [alkylphenone photopolymerization initiator]
・Irgacure 819: Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (manufactured by BASF, trade name) [acylphosphine oxide photopolymerization initiator]
・Irgacure 369: 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (manufactured by BASF, trade name) [alkylphenone photopolymerization initiator]
・Irgacure OXE02: Ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(0-acetyloxime) (manufactured by BASF, trade name) [oxime Ester-based photopolymerization initiator]
・Irgacure TPO: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (manufactured by BASF, trade name) [acylphosphine oxide photopolymerization initiator, oxime ester photopolymerization initiator]
(C) Polymerization inhibitor/AW-300 (ANTAGE W-300; 4,4'-butylidene-bis(6-tert-butyl-m-cresol, manufactured by Kawaguchi Chemical Co., Ltd., trade name)
(D) Photopolymerizable compound/DPHA: Dipentaerythol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name)
(E) Pigment/phthalocyanine pigment: Phthalocyanine pigment (manufactured by Sanyo Shiki Co., Ltd.)
(F) Inorganic filler B34: barium sulfate particles (manufactured by Sakai Chemical Industry Co., Ltd., trade name, average particle size: 0.3 μm)
・SFP-20M: Silica particles (Denka Co., Ltd., trade name, average particle size: 0.3 μm)
(G) Curing agent/curing agent: YX4000X (manufactured by Mitsubishi Chemical Corporation, trade name, biphenyl type epoxy resin)
(H) Epoxy resin curing agent/melamine: Manufactured by Nissan Chemical Industries, Ltd.

Next, each evaluation was performed under the conditions shown below using the photosensitive resin composition obtained above. The evaluation results are shown in Table 2.

[Method for preparing test piece]
The photosensitive resin compositions of Examples and Comparative Examples were screened onto a copper-clad laminate board (MCL-E-67, manufactured by Hitachi Chemical Co., Ltd.) with a thickness of 0.6 mm so that the film thickness after drying was 35 μm. After coating by a printing method, it was dried at 80° C. for 20 minutes using a hot air circulation dryer. Next, a negative mask having a predetermined pattern (a pattern with a hole diameter of 50 μm and a hole center distance of 50 μm) was brought into close contact with the coating film, and exposed using an ultraviolet exposure device at an exposure dose of 100 mJ/cm ² . Thereafter, spray development was performed using a 1% by mass aqueous sodium carbonate solution for 60 seconds at a pressure of 1.765×10 ⁵ Pa, and the unexposed areas were developed by dissolving. Next, post-exposure was performed using an ultraviolet exposure device at an exposure dose of 1000 mJ/cm ² , and post-heating was performed at 150° C. for 1 hour to produce a test piece having a permanent mask resist.

[Resist shape]
The test piece prepared by the above method was cast in an epoxy resin (jER828 (trade name, manufactured by Mitsubishi Chemical Corporation) using triethylenetetramine as a curing agent) and sufficiently cured. Co., Ltd.)) to cut out a cross section of the pattern, and the resist shape was observed using a metallurgical microscope. The resist shape was evaluated based on the following criteria.
A: Regarding the resist shape, no undercuts or missing portions of the upper part of the resist were observed, and the pattern outline had a good linear shape (see FIG. 1).
B: The resist shape was confirmed to have undercuts and missing portions of the upper part of the resist, and the pattern outline was poorly linear (see FIG. 2).

[Adhesion]
The photosensitive resin compositions of Examples and Comparative Examples were applied to a 35 μm thick copper foil (manufactured by Nippon Denki Co., Ltd.) by a screen printing method so that the film thickness after drying was 35 μm, and then heated at 80°C. It was dried for 20 minutes using a hot air circulation dryer. Next, the negative mask was brought into close contact with the coating film, and the photosensitive layer was exposed to light at an exposure dose of 100 mJ/cm ² using an exposure machine (manufactured by Oak Seisakusho Co., Ltd., trade name: EDi-5008). Thereafter, spray development was performed using a 1% by mass aqueous sodium carbonate solution for 60 seconds at a pressure of 1.765×10 ⁵ Pa, and the unexposed areas were developed by dissolving. Next, post-exposure was performed using an ultraviolet exposure device at an exposure dose of 1000 mJ/cm ² , and post-heating was performed at 150° C. for 1 hour to produce a test piece with a permanent mask resist provided on the copper foil. The surface of the obtained test piece on which the permanent mask resist was provided was attached to a copper-clad laminate (MCL-E-67, manufactured by Hitachi Chemical Co., Ltd.) using an adhesive (manufactured by Nichiban Co., Ltd., trade name: Araldite). I let it harden and glued it.
After leaving it for 12 hours, 10 mm of one end of the copper foil was peeled off. Next, the laminate was fixed, the peeled copper foil was grabbed with a grip, and the load (peel strength) when peeled off at room temperature was measured 8 times at a pulling speed of 50 mm/min in the thickness direction (vertical direction) of the copper foil. The average value was calculated from the eight measured values and used as an index of adhesion (adhesive strength). The adhesion (peel strength) was evaluated in accordance with JIS C 5016 (1994-Peel strength of conductor) and evaluated based on the following criteria. Further, in this specification, room temperature refers to 25°C.
A: Peel strength was greater than 0.5 kN/mm.
B: Peel strength was in the range of 0.3 to 0.5 kN/mm.
C: Peel strength was less than 0.3 kN/mm.

[HAST resistance]
A test piece was prepared in the same manner as described in [Method for preparing a test piece] above, except that a bismaleimide triazine substrate on which interdigitated electrodes (line/space = 10 μm/10 μm) were formed was used instead of a copper-clad laminate board. was formed and exposed to 135°C, 85%, and 5V conditions. Thereafter, the degree of occurrence of migration was observed using a metallurgical microscope with a magnification of 100 times, and evaluated based on the following criteria.
A: The resistance value did not decrease to 10 ⁻⁶ Ω or less even after 200 hours or more.
B: The resistance value did not decrease to 10 ⁻⁶ Ω or less for 100 hours or more and less than 200 hours.
C: The resistance value decreased to 10 ⁻⁶ Ω or less in less than 100 hours.

[Solder heat resistance]
A water-soluble flux was applied to a test piece prepared in the same manner as described in the above [Method for preparing a test piece], and the test piece was immersed in a solder bath at 265° C. for 10 seconds. After repeating this for 6 cycles, the appearance of the permanent mask resist was visually observed and evaluated based on the following criteria.
3: There was no change in appearance within a 30 cm x 30 cm permanent mask resist.
2: One to five flakes or blisters of the coating film occurred within a 30 cm x 30 cm permanent mask resist.
1: Six or more flakes or blisters of the coating film occurred within a 30 cm x 30 cm permanent mask resist.

[Crack resistance]
After repeating 1000 cycles of -65°C 30 minutes/(room temperature; 25°C)/150°C 30 minutes using a test piece prepared in the same manner as described in the above [Test piece preparation method], a permanent mask was used. The appearance of the resist was visually observed and evaluated based on the following criteria.
3: There was no change in appearance within a 30 cm x 30 cm permanent mask resist.
2: One to five flakes or blisters of the coating film occurred within a 30 cm x 30 cm permanent mask resist.
1: Six or more flakes or blisters of the coating film occurred within a 30 cm x 30 cm permanent mask resist.

[Solvent resistance]
A test piece prepared in the same manner as described in the above [Test piece preparation method] was immersed in isopropyl alcohol for 30 minutes at room temperature (25°C, the same applies hereinafter), and after checking whether there was any abnormality in the appearance of the permanent mask resist, A peel test was conducted using cellophane tape.
3: There was no abnormality in the appearance of the permanent mask resist, and no peeling occurred.
2: Only a slight change occurred in the appearance of the permanent mask resist.
1: There was an abnormality in the appearance of the permanent mask resist, or peeling occurred.

[Acid resistance]
A test piece prepared in the same manner as described in [Test piece preparation method] above was immersed in a 10% by mass hydrochloric acid aqueous solution at room temperature for 30 minutes, and after confirming that there were no abnormalities in the appearance of the permanent mask resist, it was peeled off with cellophane tape. The test was conducted.
3: There was no abnormality in the appearance of the permanent mask resist, and no peeling occurred.
2: Only a slight change occurred in the appearance of the permanent mask resist.
1: There was an abnormality in the appearance of the permanent mask resist, or peeling occurred.

[Alkali resistance]
A test piece prepared in the same manner as described in the above [Test piece preparation method] was immersed in a 5% by mass sodium hydroxide aqueous solution at room temperature for 30 minutes, and after confirming that there were no abnormalities in the appearance of the permanent mask resist, cellophane tape was applied. A peel test was conducted using
3: There was no abnormality in the appearance of the permanent mask resist, and no peeling occurred.
2: Only a slight change occurred in the appearance of the permanent mask resist.
1: There was an abnormality in the appearance of the permanent mask resist, or peeling occurred.

As shown in Table 2, the photosensitive resin composition containing the polymerization inhibitor was able to form a resist pattern with excellent resist shape. Furthermore, the HAST resistance also showed a good result of "A". In addition, the formed resist pattern has excellent adhesion and insulation properties, and is also rated "3" in terms of soldering heat resistance, crack resistance, solvent resistance, acid resistance, and alkali resistance. I know that there is. On the other hand, the photosensitive resin compositions of Comparative Examples 1 to 5 that did not contain a polymerization inhibitor had poor effects in terms of resist shape and HAST resistance.

(Examples 11-20, Comparative Examples 6-10)
Each of the photosensitive resin compositions of Examples 1 to 10 and Comparative Examples 1 to 5 prepared at the compounding ratio shown in Table 1 was diluted with methyl ethyl ketone and applied on a 25 μm thick polyethylene terephthalate (PET) film. It was dried at ℃ for 10 minutes to form a photosensitive layer made of the photosensitive resin composition with a thickness of 25 μm. Further, a cover film (polypropylene film with a thickness of 15 μm) was laminated thereon to produce dry films of Examples 11 to 20 and Comparative Examples 6 to 10, respectively.

[Dry film evaluation]
The cover film was peeled off from the dry film obtained above, the dry film was thermally laminated on a solid copper foil substrate, and then exposed in the same manner as described in [Preparation of test piece] above to form a permanent mask resist. A test piece having the following properties was prepared.
Evaluations similar to those in Example 1 were performed using the obtained test pieces. The results are shown in Table 3.

As shown in Table 3, the photosensitive resin composition containing the polymerization inhibitor was able to form a resist pattern with excellent resist shape. Furthermore, the HAST resistance also showed a good result of "A". In addition, the formed resist pattern has excellent adhesion and insulation properties, and is also rated "3" in terms of soldering heat resistance, crack resistance, solvent resistance, acid resistance, and alkali resistance. I know that there is. On the other hand, the photosensitive resin compositions of Comparative Examples 6 to 10 (Comparative Examples 1 to 5) that did not contain a polymerization inhibitor were inferior in terms of resolution and HAST resistance.

Claims (15)

A method for producing a photosensitive resin composition comprising (A) an acid-modified vinyl group-containing epoxy resin, (B) a photopolymerization initiator, (C) a polymerization inhibitor, and (D) a photopolymerizable compound,
The acid-modified vinyl group-containing epoxy resin (A) comprises at least one acid-modified vinyl group-containing epoxy resin (A1) synthesized using a bisphenol novolac type epoxy resin (a1), and the epoxy resin (a1). contains at least one acid-modified vinyl group-containing epoxy resin (A2) synthesized using a different epoxy resin (a2),
A first antioxidant is optionally used during the synthesis of the acid-modified vinyl group-containing epoxy resin (A),
The method for producing a photosensitive resin composition, wherein the polymerization inhibitor (C) is a second antioxidant added after synthesizing the acid-modified vinyl group-containing epoxy resin (A). Production of the photosensitive resin composition according to claim 1, wherein the content of the polymerization inhibitor (C) is 0.01 to 2% by mass based on the total solid content in the photosensitive resin composition. Method. 3. The epoxy resin (a2) is at least one selected from the group consisting of novolak epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, and triphenolmethane epoxy resin. A method for producing a photosensitive resin composition. The acid-modified vinyl group-containing epoxy resin (A1) is a resin (A1') obtained by reacting the epoxy resin (a1) with a vinyl group-containing monocarboxylic acid (b), and a saturated or unsaturated group-containing polybase. A resin obtained by reacting an acid anhydride (c), and the acid-modified vinyl group-containing epoxy resin (A2) is obtained by reacting the epoxy resin (a2) with a vinyl group-containing monocarboxylic acid (b). Production of the photosensitive resin composition according to any one of claims 1 to 3 , which is a resin obtained by reacting the resin (A2') with a saturated or unsaturated group-containing polybasic acid anhydride (c). Method . The bisphenol novolac type epoxy resin (a1) is a bisphenol novolac type epoxy resin having a structural unit represented by the following general formula (I) and a bisphenol novolac type epoxy resin having a structural unit represented by the following general formula (II). At least one type selected from the group consisting of

[In general formula (I), R ¹¹ represents a hydrogen atom or a methyl group, and Y ¹ and Y ² each independently represent a hydrogen atom or a glycidyl group. A plurality of R ^11s may be the same or different, and at least one of Y ¹ and Y ² represents a glycidyl group. ]

[In general formula (II), R ¹² represents a hydrogen atom or a methyl group, and Y ³ and Y ⁴ each independently represent a hydrogen atom or a glycidyl group. A plurality of R ^12s may be the same or different, and at least one of Y ³ and Y ⁴ represents a glycidyl group. ]
The epoxy resin (a2) is a novolac type epoxy resin having a structural unit represented by the following general formula (III), a bisphenol type epoxy resin having a structural unit represented by the following general formula (IV), and the following general formula ( The method for producing a photosensitive resin composition according to any one of claims 1 to 4 , wherein the photosensitive resin composition is at least one selected from the group consisting of triphenolmethane type epoxy resins having a structural unit represented by V).

[In general formula (III), R ¹³ represents a hydrogen atom or a methyl group, Y ⁵ represents a hydrogen atom or a glycidyl group, and the molar ratio of the hydrogen atom to the glycidyl group (hydrogen atom/glycidyl group) is 0/ It is 100 to 30/70. ]

[In general formula (IV), R ¹⁴ represents a hydrogen atom or a methyl group, Y ⁶ represents a hydrogen atom or a glycidyl group, and the molar ratio of the hydrogen atom to the glycidyl group (hydrogen atom/glycidyl group) is 0/ 100 to 30/70, and multiple R ^14s may be the same or different. ]


[In general formula (V), Y ⁷ represents a hydrogen atom or a glycidyl group, a plurality of Y ^7s may be the same or different, and at least one Y ⁷ is a glycidyl group. ] The bisphenol novolac type epoxy resin (a1) has a structural unit represented by the general formula (I), and the epoxy resin (a2) has a structural unit represented by the general formula (IV). The method for producing a photosensitive resin composition according to claim 5 , which comprises a bisphenol A type epoxy resin or a bisphenol F type epoxy resin. The photopolymerization initiator of component (B) is an alkylphenone photopolymerization initiator, an acylphosphine oxide photopolymerization initiator, a photopolymerization initiator having a thioxanthone skeleton, a titanocene photopolymerization initiator, and an oxime ester photopolymerization initiator. The method for producing a photosensitive resin composition according to any one of claims 1 to 6 , wherein the initiator is at least one selected from the group consisting of initiators. A claim in which the photopolymerization initiator of component (B) is at least one selected from the group consisting of an alkylphenone photopolymerization initiator, an acylphosphine oxide photopolymerization initiator, and an oxime ester photopolymerization initiator. 8. A method for producing a photosensitive resin composition according to any one of items 1 to 7 . The method for producing a photosensitive resin composition according to any one of claims 1 to 8 , wherein the photopolymerization initiator as the component (B) is an acylphosphine oxide photopolymerization initiator. The method for producing a photosensitive resin composition according to any one of claims 1 to 9 , further comprising (E) a pigment. The method for producing a photosensitive resin composition according to any one of claims 1 to 10 , further comprising (F) an inorganic filler. A method for producing a dry film comprising a carrier film and a photosensitive layer,
A method for producing a dry film, wherein the photosensitive layer is formed using a photosensitive resin composition produced by the method for producing a photosensitive resin composition according to any one of claims 1 to 11 . A method for producing a printed wiring board , comprising forming a permanent mask resist using a photosensitive resin composition produced by the method for producing a photosensitive resin composition according to any one of claims 1 to 11 . The method for manufacturing a printed wiring board according to claim 13 , wherein the thickness of the permanent mask resist is 10 μm or more. On the substrate, a photosensitive resin composition produced by the method for producing a photosensitive resin composition according to any one of claims 1 to 11 , or a dry film produced by the method for producing a dry film according to claim 12 . A method for manufacturing a printed wiring board, comprising, in order, providing a photosensitive layer using a film, forming a resist pattern using the photosensitive layer, and curing the resist pattern to form a permanent mask resist.