JP2006267152A - Photosensitive dry film for protection film of printed wiring board and method for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive dry film for a protection film of a printed wiring board, the dry film having suppressed blocking. <P>SOLUTION: The dry film comprises a photosensitive layer (II) layered on a supporting film (I), wherein the supporting film (I) is a polyester film having ≤1.0 mass% oligomer content and containing an antiblocking agent by 0.01 to 0.50 mass%. The invention also discloses a photosensitive dry film roll for a protection film of a printed wiring board as a roll form of the above dry film, and a method for manufacturing the dry film. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a photosensitive dry film for a printed wiring board protective film and a dry film roll in the form of a roll. More specifically, the film blocking is suppressed and a printed wiring board protective film having good performance is provided. It is related with the dry film which can be manufactured, and its manufacturing method.

  In the production of a printed wiring board, a protective film (hereinafter sometimes referred to as a “permanent protective film”) is formed on the surface of the conductor circuit in order to protect the conductive circuit and maintain insulation between conductors. Has been done. For the formation of such a protective film, a photosensitive dry film comprising a photosensitive layer on a support film and a protective film provided on the photosensitive layer to protect the photosensitive layer is used. A polyethylene terephthalate film is used as the protective film, and a polyethylene film or a polyethylene terephthalate film is frequently used as the protective film (for example, see JP-A-2002-156754; Patent Document 1).

  A dry film composed of such a support film, a photosensitive layer and a protective film may be used in a roll form, and the support film and the protective film are in contact with each other on the surfaces where the photosensitive layer is not in contact. It becomes. In such a case, so-called blocking may occur where the films are in close contact with each other and are difficult to peel off. This is remarkable when flexible films such as low-density polyethylene are used even between the same kind of films or different kinds of films, and particularly when the dry film is made into a roll, the tension at the time of roll production remains. It will encourage the trend. In particular, when a low-density polyethylene film that does not contain the addition of an antiblocking agent or the like is used as the protective film, this is remarkable.

  When such blocking occurs in the dry film roll, workability is lowered, for example, it becomes difficult to feed the dry film from the roll. Furthermore, since the close contact between the support film and the protective film is strong, peeling occurs between the photosensitive layer and the protective film or between the photosensitive layer and the support film at the time of feeding, and it may be difficult to use in subsequent processes. In addition, excessive stress is applied to the photosensitive layer during unwinding, and the photosensitive layer may be damaged particularly in a photosensitive layer that requires heat resistance for a permanent protective film.

  As a method for preventing blocking of the film, an antiblocking agent is added. If the antiblocking agent is poorly dispersed, a convex gel is formed on the film surface. When such a gel is generated in the support film of the dry film, there are problems that ultraviolet rays are scattered at the time of exposure and the shape of the resist pattern becomes unclear, or the photosensitivity of the dry film is lowered due to a decrease in transparency.

  In addition, the stress concentrates on the photosensitive layer in contact with the part where the gel is present, so that the film thickness of the photosensitive layer is locally reduced or, in severe cases, pinholes are formed, resulting in a decrease in performance as a permanent protective film. There is a problem of doing. In particular, when the dry film is formed into a roll shape, the tension at the time of roll production remains, and this tendency is promoted.

  Even if there is a local film thickness change in such a photosensitive layer, the etching resist is hardened by exposure, that is, in the etching process, the time required for the process is short and the influence on the original function is small, but it is permanent. In the protective film, the heat resistance of the solder may decrease due to a local change in film thickness, and the insulation characteristics may deteriorate in the long-term use, which is a big problem in the dry film for the permanent protective film.

  As a polyester film for a dry film resist support, a polyethylene terephthalate film containing fine particles such as silica is known (for example, JP-A-2002-178475; Patent Document 2). It is added in order to improve slipperiness. These are added for the purpose of blocking the film and have a technical idea different from the present invention which is added in a specific range in order to ensure the performance of the permanent protective film. The technical idea is also different from the present invention in that the problem that occurs when the film is rolled is solved.

JP 2002-156754 A JP 2002-178475 A

  It is an object of the present invention to provide a photosensitive dry film for a printed wiring board protective film in which blocking of the dry film is suppressed and a method for producing the same.

（式中、Ｘは単結合、メチレン基、エチリデン基、イソプロピリデン基、またはスルホニル基を表し、Ｙは水素原子または２，３−エポキシプロピル基を表し、ｎは１〜１０の整数であり、ｎが１の場合、Ｙは２，３−エポキシプロピル基を表し、ｎが２〜１０の場合、ｎ個のＸ及びＹは、各々同一でも異なってもよいが、少なくともひとつのＹは２，３−エポキシプロピル基を表す。）
で示されるビスフェノール型エポキシ樹脂（ａ）と不飽和基含有モノカルボン酸（ｂ）との反応生成物に、多塩基酸無水物（ｃ）を反応させて得られるものである前記１１記載のプリント配線板保護膜用感光性ドライフィルム。
１３．（Ａ）カルボキシル基を有する光硬化性樹脂、（Ｂ）光重合開始剤及び（Ｃ）エポキシ樹脂を必須成分とする感光性組成物が、さらに（Ｄ）光硬化性モノマーまたはオリゴマーを含む前記１０〜１２のいずれかひとつに記載のプリント配線板保護膜用感光性ドライフィルム。
１４．前記１〜１３のいずれかひとつに記載のプリント配線板保護膜用感光性ドライフィルムをロール状の形態としたプリント配線板保護膜用感光性ドライフィルムロール。
１５．少なくとも下記工程（イ）〜（ホ）：
（イ）ロール状に巻き取られた（Ｉ）支持フィルムから、（Ｉ）支持フィルムを繰り出す工程、
（ロ）繰り出された（Ｉ）支持フィルム上に感光性組成物を連続的に塗布する工程、
（ハ）（Ｉ）支持フィルム上に塗布された感光性組成物を乾燥し、（II）感光層を形成する工程、
（ニ）ロール状に巻き取られた保護フィルムから（III）保護フィルムを繰り出して前記（II）感光層上に貼合し、ドライフィルムレジストを形成する工程、
（ホ）形成されたドライフィルムレジストをロール状に巻き取る工程、
を含み、前記（Ｉ）支持フィルムが、オリゴマー含有量1.0質量％以下のポリエステルフィルムであり、かつアンチブロッキング剤0.01〜0.50質量％を含有することを特徴とするプリント配線板保護膜用感光性ドライフィルムロールの製造方法。 The present inventor uses a polyester film having a specific amount of anti-blocking agent as a support film and a specific oligomer content in a photosensitive dry film, and thus has excellent blocking resistance and good performance. The present inventors have found that a protective film can be provided and have completed the present invention. That is, this invention relates to the photosensitive dry film for printed wiring board protective films shown to the following 1-15, the photosensitive dry film roll for printed wiring board protective films which made the dry film the roll form, and its manufacturing method.
1. (I) A dry film in which (II) a photosensitive layer is laminated on a support film, wherein the (I) support film is a polyester film having an oligomer content of 1.0% by mass or less, and an antiblocking agent 0.01 to A photosensitive dry film for a printed wiring board protective film, comprising 0.50% by mass.
2. 2. The photosensitive dry film for a printed wiring board protective film according to 1 above, wherein the polyester film is a polyethylene terephthalate film.
3. (II) The photosensitive dry film for a printed wiring board protective film according to 1 or 2 above, wherein (III) a protective film is laminated on the surface opposite to the surface on which the (I) support film is laminated.
4). (III) The photosensitive dry film for a printed wiring board protective film as described in 3 above, wherein the protective film is a polyester film.
5. 5. The photosensitive dry film for a printed wiring board protective film according to 4 above, wherein the polyester film is a polyethylene terephthalate film.
6). (III) The photosensitive dry film for a printed wiring board protective film as described in 5 above, wherein the protective film has a release agent layer on the surface facing the photosensitive layer (II).
7). 7. The photosensitive dry film for a printed wiring board protective film according to 6 above, wherein the release agent layer contains silicone as a main component.
8). (III) The photosensitive dry film for a printed wiring board protective film as described in 3 above, wherein the protective film is a polyolefin film.
9. 9. The photosensitive dry film for a printed wiring board protective film as described in 8 above, wherein the polyolefin film is a low density polyethylene film or a polypropylene film.
10. (II) The photosensitive layer is formed of a photosensitive composition containing (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator, and (C) an epoxy resin as essential components. The photosensitive dry film for printed wiring board protective films as described in any one of -9.
11. (A) The photosensitive dry film for printed wiring board protective films according to 10, wherein the photocurable resin having a carboxyl group is an epoxy (meth) acrylate resin having a carboxyl group.
12 An epoxy (meth) acrylate resin having a carboxyl group is represented by the following general formula (1):

(In the formula, X represents a single bond, a methylene group, an ethylidene group, an isopropylidene group, or a sulfonyl group, Y represents a hydrogen atom or a 2,3-epoxypropyl group, and n is an integer of 1 to 10, When n is 1, Y represents a 2,3-epoxypropyl group. When n is 2 to 10, n X and Y may be the same or different, but at least one Y is 2, Represents a 3-epoxypropyl group.)
12. The print according to 11 above, which is obtained by reacting a polybasic acid anhydride (c) with a reaction product of the bisphenol type epoxy resin (a) and the unsaturated group-containing monocarboxylic acid (b) represented by Photosensitive dry film for wiring board protective film.
13. (A) A photocurable resin having a carboxyl group, (B) a photopolymerization initiator, and (C) a photosensitive composition containing epoxy resin as essential components further includes (D) a photocurable monomer or oligomer. The photosensitive dry film for printed wiring board protective films as described in any one of -12.
14 The photosensitive dry film roll for printed wiring board protective films which made the photosensitive dry film for printed wiring board protective films as described in any one of said 1-13 into a roll form.
15. At least the following steps (a) to (e):
(I) a step of (I) feeding out the support film from the (I) support film wound up in a roll;
(B) a step of continuously applying the photosensitive composition onto the drawn out (I) support film;
(C) (I) drying the photosensitive composition coated on the support film, and (II) forming a photosensitive layer;
(D) a step of drawing out a protective film (III) from a protective film wound up in a roll shape and pasting it on the photosensitive layer (II) to form a dry film resist;
(E) a step of winding the formed dry film resist into a roll,
And (I) the support film is a polyester film having an oligomer content of 1.0% by mass or less, and contains 0.01 to 0.50% by mass of an antiblocking agent. Film roll manufacturing method.

  Since the present invention uses a polyester resin having a specific oligomer content as a support film and uses a specific amount of an anti-blocking agent, blocking of the dry film roll is suppressed, and heat resistance, photosensitivity, insulation characteristics, etc. It provides a good and reliable printed wiring board protective film. This is particularly effective when low-density polyethylene containing no antiblocking agent is used for the protective film, or when a polyester film having a release agent layer on the surface is used.

  The (I) support film used in the present invention is formed by molding a polyester resin into a film by an arbitrary method. Known polyester resins can be used, and specific examples include polyethylene terephthalate and polyethylene naphthalate. The intrinsic viscosity (orthochlorophenol, 35 ° C.) of these polyester resins is preferably preferably 0.52 to 1.50 dl / g, more preferably 0.57 to 1.00 dl / g, and particularly preferably 0.60 to 0.80 dl / g. When the intrinsic viscosity is less than 0.52 dl / g, the tear strength may be insufficient, which is not preferable. On the other hand, when the intrinsic viscosity exceeds 1.50 dl / g, productivity in the raw material manufacturing process and the film forming process may be impaired.

  (I) There is no restriction | limiting in particular in the manufacturing method of polyester resins, such as a polyethylene terephthalate used for a support film, For example, after making an esterification reaction of terephthalic acid and ethylene glycol, it aims at the obtained reaction product. Polyethylene terephthalate can be obtained by polycondensation reaction in a molten state until the degree of polymerization is reached. As a preferred example, a method of transesterifying terephthalic acid dimethyl ester and ethylene glycol and then subjecting the obtained reaction product to a polycondensation reaction in a molten state until a desired degree of polymerization is obtained to form polyethylene terephthalate. Is mentioned. Furthermore, the polyethylene terephthalate obtained by the polycondensation reaction in the molten state can be made into a polymer having a higher degree of polymerization by performing a polymerization reaction in a solid phase state as necessary.

  In the present invention, the polyester film used as the support film (I) has an oligomer content of 1.0% by mass or less, preferably 0.8% by mass or less, more preferably 0.6% by mass or less, and particularly preferably 0.5% by mass or less. Most preferably, it is 0.4 mass% or less. When the oligomer content exceeds 1.0% by mass, even if an antiblocking agent within the range of the present invention is added, the antiblocking effect is not observed. When the oligomer content exceeds 1.0% by mass, the addition of an antiblocking agent in an amount exceeding the range of the present invention can provide an antiblocking effect. In this case, however, a gel tends to occur on the support film, and a photosensitive layer is formed. When the film thickness of the photosensitive layer is locally reduced due to repellency at the time or deformation of the photosensitive layer during storage, the performance as a permanent protective film is deteriorated. Moreover, since the transparency of a film falls, the sensitivity of a photosensitive dry film falls. Furthermore, since the oligomer moves to the interface between the (I) support film and the (II) photosensitive layer, the adhesion strength between the (I) support film and the (II) photosensitive layer decreases over time, or (II) The surface properties of the permanent protective film formed by curing the layer may be lowered.

  There is no restriction | limiting in particular in the method of manufacturing polyester with an oligomer content of 1.0 mass% or less, It can manufacture by a well-known method. These production methods include, for example, a method in which an oligomer component is extracted from a polyester film having an oligomer content exceeding 1.0% by mass with an organic solvent or the like so that the oligomer content is 1.0% by mass or less. In addition, as a polyester resin that is a raw material of the polyester film, there is a method of using a polyester resin in which the oligomer content is reduced by adjusting polymerization conditions, and a method of using a material in which the metal catalyst component in the resin is removed by washing or the like. Can be mentioned. In the latter method, oligomer formation at the time of film formation is suppressed, and a film having a low oligomer content can be easily obtained.

  There is no restriction | limiting in particular in the thickness of (I) support film used by this invention, Usually, it is 1-200 micrometers, Preferably it is 1-100 micrometers, More preferably, it is 5-80 micrometers, More preferably, it is 8-50 micrometers, More preferably, it is 8 It is ˜40 μm, particularly preferably 10 to 35 μm, most preferably 10 to 30 μm. If the thickness is less than 1 μm, the strength is insufficient, and workability at the time of peeling the support film may be lowered. On the other hand, if the thickness exceeds 200 μm, the pattern shape after exposure may become unclear.

  The (I) support film used in the present invention is characterized by containing 0.01 to 0.5% by mass of an antiblocking agent. The anti-blocking agent is a substance having a function of suppressing adhesion or adhesion between films, and an inorganic type or an organic type is used without particular limitation.

  Inorganic antiblocking agents include fused silica, synthetic silica, natural silica, silica, alumina, titania, composite oxides thereof, zeolites such as A-type zeolite, Pc-type zeolite, and X-type zeolite, talc, kaolin, alumino Examples include silicate, diatomaceous earth, and talc. Any of these may be subjected to treatment such as acid modification or ion exchange.

  Examples of the organic antiblocking agent include cross-linked acrylate resin, cross-linked polymethyl methacrylate, cross-linked polystyrene, non-melt type silicone resin and silicone rubber, silicone-based copolymer, polyamide, condensation resin having triazine ring, and melamine resin. And thermosetting resins such as guanamine resin, phenol resin, and urea resin. These are used in the form of powder, preferably spherical fine particles. These antiblocking agents may be used alone or in combination of two or more.

  The average particle size of these antiblocking agents is arbitrary, but is usually 0.1 to 10.0 μm, preferably 0.3 to 8.0 μm, more preferably 0.5 to 6.0 μm, still more preferably 0.8 to 5.0 μm, and particularly preferably 1.0 to 4.0 μm. If the average particle size is less than 0.1 μm, the blocking inhibitory effect may not be seen, and if it exceeds 10.0 μm, the blocking inhibitory effect may not be seen.

  The blending amount of the anti-blocking agent is 0.01 to 0.50 mass% in the (I) support film, preferably 0.01 to 0.30 mass%, more preferably 0.01 to 0.20 mass%, still more preferably 0.02 to 0.15 mass%, and more. More preferably, it is 0.02-0.10 mass%, Most preferably, it is 0.02-0.09 mass%, Most preferably, it is 0.03-0.08 mass%. If the blending amount is less than 0.01% by mass, the anti-blocking effect may not be seen. If the blending amount exceeds 0.50% by mass, the photosensitivity of the dry film may decrease due to a decrease in transparency. Further, the generation of gel causes scattering of ultraviolet rays or the like at the time of exposure, and the shape of the resist pattern may become unclear.

  Furthermore, the film thickness of the photosensitive layer is locally reduced due to the generation of gel, and bubbles remain when laminated with a substrate having a circuit pattern, and it becomes difficult to follow the photosensitive layer to the circuit pattern. In extreme cases, gel may cause pinholes in the photosensitive layer. All of these deteriorate the performance as a permanent protective film, and bring about a decrease in solder heat resistance and insulation characteristics.

  An antiblocking agent can be added by arbitrary methods, for example, is added by melt-kneading after manufacturing a polyester resin. In this method, the antiblocking agent is preferably added as a master pellet diluted in advance to a concentration of about 10% by mass. Further, it can be added to the reaction system at the time of the reaction for producing the polyester resin, for example, by the transesterification method, at any time during the transesterification or polycondensation reaction, or at any time in the case of the direct polymerization method. . In particular, the antiblocking agent particles are preferably added to the reaction system at the beginning of the polycondensation reaction, for example, until the intrinsic viscosity reaches about 0.3 dl / g.

  The (I) support film used in the present invention is produced by any method. For example, a polyester resin that forms the support film, an antiblocking agent, and other additives as necessary are mixed, and a known kneading apparatus such as a single screw extruder, a twin screw extruder, a kneader, or a Banbury mixer is used. After being kneaded at a temperature of about 100 to 300 ° C., it is formed into a film by extrusion molding with an extruder or the like equipped with a T die or the like.

  The (I) support film used in the present invention may be a single layer film or a multilayer film. Further, (I) the support film may be either an unstretched film or a stretched film, and in the case of a stretched film, it may be either uniaxial or biaxially stretched. In stretching, a known method can be adopted. After producing a film raw material using an extruder or the like, the film raw material is continuously or simultaneously used by using a tenter type, pantograph type stretching device or the like. Stretching can also be performed. (I) The support polymer film may be subjected to various treatments such as corona treatment.

  Further, (I) the support film may be formed by forming a release agent layer on the surface opposite to the surface in contact with (II) the photosensitive layer. The release agent layer is a known release agent such as silicone, silicone surfactant, fluorine surfactant, polyalkylene glycol surfactant, polyalkylene amine surfactant, acrylic surfactant, hydrocarbon wax, etc. It is formed by applying or laminating. In particular, when the dry film of the present invention is produced without using the (III) protective film and is made into a roll shape, it is preferable to use the (I) support film on which the release agent layer is formed.

  Next, the (II) photosensitive layer used in the present invention will be described. (II) The photosensitive layer is formed from any composition used as a protective film for a printed wiring board, and preferably (A) a photocurable resin having a carboxyl group, and (B) initiation of photopolymerization. And (C) a photosensitive composition containing an epoxy resin as essential components.

  (A) A photocurable resin having a carboxyl group, which is used in a photosensitive composition containing (A) a carboxyl group-containing photocurable resin, (B) a photopolymerization initiator, and (C) an epoxy resin as essential components. Any resin can be used. The amount used thereof is 10 to 90% by mass in the photosensitive layer (II), preferably 20 to 80% by mass, particularly preferably 25 to 70% by mass, and most preferably 30 to 60% by mass. (A) When the usage-amount of the photocurable resin which has a carboxyl group is less than 10 mass% or exceeds 90 mass%, hardening will become inadequate and heat resistance will fall.

  (A) The photocurable resin having a carboxyl group is preferably a reaction product of a bisphenol type epoxy resin (a) represented by the following general formula (1) and an unsaturated group-containing monocarboxylic acid (b). It is obtained by reacting basic acid anhydride (c).

前記一般式（１）において、ｎは１〜１０の整数である。

In the said General formula (1), n is an integer of 1-10.

  In the general formula (1), X is selected from a single bond, a methylene group, an ethylidene group, an isopropylidene group and a sulfonyl group, preferably a methylene group or an isopropylidene group, and most preferably a methylene group.

  In the general formula (1), Y is selected from a hydrogen atom or a 2,3-epoxypropyl group. When n = 1, Y is a 2,3-epoxypropyl group, and n is 2 or more. In some cases, at least one Y is a 2,3-epoxypropyl group.

  The unsaturated group-containing monocarboxylic acid (b) used in the present invention is a compound having one carboxyl group and one or more unsaturated groups in one molecule. Specifically, acrylic acid, acrylic Examples include acid dimers, methacrylic acid, β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, α-cyanocinnamic acid, and the like. These unsaturated group-containing monocarboxylic acids (b) can be used alone or in combination. Among these, acrylic acid or methacrylic acid is preferable, and acrylic acid is most preferable.

  In the reaction of the epoxy resin (a) with the unsaturated group-containing monocarboxylic acid (b), the unsaturated group-containing monocarboxylic acid (b) is 0.8 to 1.2 with respect to 1 equivalent of the epoxy group of the epoxy resin (a). It is preferable to make it react by the ratio used as an equivalent, and also the ratio used as 0.9-1.0 equivalent is preferable.

  The reaction between the epoxy resin (a) and the unsaturated group-containing monocarboxylic acid (b) is usually carried out in an organic solvent. Organic solvents used here include ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene, methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol Glycol ethers such as monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether, esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, carbitol acetate, octane, decane, etc. Examples thereof include petroleum hydrocarbons such as aliphatic hydrocarbons, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

  The reaction can also be performed in the presence of a catalyst. As the catalyst, for example, triethylamine, benzylmethylamine, methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, triphenylphosphine, and the like can be used.

  The usage-amount of the said catalyst is 0.1-10 mass parts with respect to a total of 100 mass parts of an epoxy resin (a) and an unsaturated group containing monocarboxylic acid (b) normally. A polymerization inhibitor is preferably used for the purpose of preventing polymerization during the reaction. Examples of the polymerization inhibitor include hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol and the like, and the amount used is a total of 100 masses of the epoxy resin (a) and the unsaturated group-containing monocarboxylic acid (b). Preferably it is 0.01-1 mass part with respect to a part. The reaction temperature is preferably 60 to 150 ° C, more preferably 80 to 120 ° C.

  The polybasic acid anhydride (c) used in the production of (A) a photocurable resin having a carboxyl group used in the present invention is a compound having one or more acid anhydride groups in one molecule. Succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride And itaconic anhydride. These may be used alone or in combination. Among these, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, and ethylhexahydrophthalic anhydride are the most preferable. Preference is given to tetrahydrophthalic anhydride.

  In the present invention, (A) the reaction of the polybasic acid anhydride (c) in the production of the photocurable resin having a carboxyl group is a reaction between the epoxy resin (a) and the unsaturated group-containing monocarboxylic acid (b). In the same solvent as that used in the step, it is usually carried out in a temperature range of 60 to 120 ° C. The amount of the polybasic acid anhydride (c) used is usually 0.1 to 2.0 equivalents relative to 1 equivalent of the hydroxyl group in the reaction product of the epoxy resin (a) and the unsaturated group-containing monocarboxylic acid (b). Yes, the acid value of the photocurable resin (A) can be adjusted by changing the amount of the polybasic acid anhydride (c) used. The acid value of the photocurable resin (A) of the present invention thus obtained is preferably 20 to 200 mgKOH / g, more preferably 50 to 150 mgKOH / g. When the acid value is less than 20 mgKOH / g, the solubility of the photocurable resin composition in a dilute alkali solution is lowered, and when it exceeds 200 mgKOH / g, the electric characteristics of the cured film tend to be lowered.

  Other preferred examples of the photocurable resin (A) having a carboxyl group used in the present invention include polyhydroxycarboxylic acid (d), polyol (e), polyisocyanate (f), and unsaturated hydroxy compound ( Examples thereof include those obtained by reacting g), and urethane (meth) acrylate resins having a carboxyl group are preferred.

  The method for producing a urethane (meth) acrylate resin having a carboxyl group from polyhydroxycarboxylic acid (d), polyol (e), polyisocyanate (f), and unsaturated hydroxy compound (g) is particularly limited. However, as a preferable production method, a method in which each component is mixed and reacted, a urethane containing one or more isocyanate groups per molecule by reacting the above (d), (e) and (f) Examples include a method of reacting the urethane isocyanate prepolymer with the above (g) after forming the isocyanate prepolymer.

  The polyhydroxycarboxylic acid (d) is a compound having two or more hydroxyl groups and one or more carboxyl groups in one molecule, and examples thereof include dimethylolpropionic acid, dimethylolbutanoic acid, and tartaric acid. Other examples of polyhydroxycarboxylic acid (d) include glycerin, trimethylolpropane, trimethylolethane, glycerol polypropoxytriol, trimethylolpropane polyethoxytriol, pentaerythritol polypropoxytetraol, trimethylolpropane. Succinic anhydride, maleic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. with respect to 1 equivalent of the hydroxyl group of a trifunctional or higher functional polyol compound such as ε-caprolactone modified Examples include compounds obtained by reacting polybasic acid anhydrides with an acid anhydride group in an amount of 0.25 to 0.5 equivalents. Of these polyhydroxycarboxylic acids (d), dimethylolpropionic acid and dimethylolbutanoic acid are preferred.

  In the present invention, the polyol (e) used for the production of the urethane (meth) acrylate resin having a carboxyl group that can be used as (A) is a compound having two or more hydroxyl groups in one molecule. , Propylene glycol, trimethylene glycol, tetramethylene glycol, butylene glycol, pentamethylene glycol, hexamethylene glycol, diethylene glycol, triethylene glycol and other dihydric alcohols, glycerin, trimethylolpropane, pentaerythritol and other polyhydric alcohols Can be mentioned. Among these, ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol and hexamethylene glycol are preferable.

  Other examples of the polyol (e) include polyether-based diols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol, polyester-based polyols obtained from esters of polyhydric alcohols and polybasic acids, hexamethylene carbonate, and pentamethylene. And polylactone diols such as polycarbonate diols, polycaprolactone diols, polybutyrolactone diols containing units derived from carbonates as constituent units. Among these, polylactone diols and polycarbonate diols are preferable.

  These polymer polyols can be used singly or in combination of a polyether diol, a polyester polyol, a polycarbonate diol, and a polylactone diol. These polymer polyols may have a carboxyl group in the molecule. The number average molecular weight of these polymer polyols is preferably 200 to 2000 from the viewpoint of flexibility.

  In the present invention, as a specific example of the polyisocyanate (f) used for producing a urethane (meth) acrylate resin having a carboxyl group that can be used as (A), specifically, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, diphenylmethylene diisocyanate, (o, m, or p) -xylene diisocyanate, methylene bis (cyclohexyl isocyanate), trimethylhexamethylene Examples thereof include diisocyanates such as diisocyanate, cyclohexane-1,3-dimethylene diisocyanate, cyclohexane-1,4-dimethylene diisocyanate and 1,5-naphthalene diisocyanate. These polyisocyanates can be used alone or in combination of two or more. Among these, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, diphenylmethylene diisocyanate, (o, m, or p) are preferable. -Xylene diisocyanate, methylene bis (cyclohexyl isocyanate), trimethylhexamethylene diisocyanate, most preferred is isophorone diisocyanate.

  In the present invention, the unsaturated hydroxy compound (g) used for the production of a urethane (meth) acrylate resin having a carboxyl group that can be used as (A) is one or more hydroxyl groups and one or more unsaturated groups in one molecule. A compound having a saturated bond, and known compounds can be used. Specific examples of the unsaturated hydroxy compound (g) include 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, caprolactone or alkylene oxide adduct of each (meth) acrylate, Glycerin mono (meth) acrylate, glycerin di (meth) acrylate, glycidyl methacrylate-acrylic acid adduct, trimethylolpropane mono (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipenta Examples include erythritol penta (meth) acrylate, ditrimethylolpropane tri (meth) acrylate, trimethylolpropane-alkylene oxide adduct-di (meth) acrylate, and the like. It is. These (meth) acrylates having a hydroxyl group can be used alone or in combination of two or more. Among these, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate are preferable, and 2-hydroxyethyl (meth) acrylate is more preferable.

  The (B) photopolymerization initiator used in the present invention is a compound having the ability to initiate polymerization of a compound having an unsaturated bond by irradiation with radiation such as ultraviolet rays, and includes benzophenone, benzoylbenzoic acid, 4-phenylbenzophenone, Benzophenones such as hydroxybenzophenone, 4,4′-bis (diethylamino) benzophenone, benzoin alkyl ethers such as benzoin, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, benzoin isobutyl ether, 4-phenoxydichloroacetophenone, 4-t -Butyl-dichloroacetophenone, 4-t-butyl-trichloroacetophenone, diethoxyacetophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butyl Acetophenones such as N-1-one, thioxanthenes such as thioxanthene, 2-chlorothioxanthene, 2-methylthioxanthene, 2,4-dimethylthioxanthene, alkyl anthraquinones such as ethyl anthraquinone, butyl anthraquinone, 2, Acylphosphine oxides such as 4,6-trimethylbenzoyldiphenylphosphine oxide, benzyldimethylketals such as 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-methyl-1- [4- (methylthio ) Phenyl] -2-morpholinopropan-1-one, α-aminoketones such as 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2-hydroxy-2 -Methyl-1-phenyl-propan-1-one, Examples include α-hydroxy ketones such as 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-propan-1-one, 9,10-phenanthrenequinone, and the like. These can be used alone or as a mixture of two or more. Moreover, a photosensitizer can be used together as needed.

  Among these (B) photopolymerization initiators, benzophenones, acetophenones, benzyl dimethyl ketals, acylphosphine oxides, α-amino ketones, α-hydroxy ketones are preferable, and 4,4′-bis ( Diethylamino) benzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,4,6- Trimethylbenzoyldiphenylphosphine oxide, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl)- Butan-1-one, 1-hydroxy-cyclohexyl-phenyl ketone, wavelength absorption It is preferable because of its high efficiency and high activity.

  The blending amount of these (B) photopolymerization initiators is 0.1 to 30% by mass, preferably 1.0 to 20% by mass, particularly preferably 2.0 to 15% in the (II) photosensitive layer of the dry film of the present invention. % By mass. (B) When the compounding quantity of a photoinitiator is less than 0.1 mass%, hardening of a photosensitive layer may become inadequate.

  The (C) epoxy resin used in the present invention is a compound having two or more epoxy groups in one molecule, and any epoxy resin can be used. These may be used alone or in combination. More specifically, bisphenol A glycidyl ether type epoxy resin, bisphenol F glycidyl ether type epoxy resin, bisphenol S glycidyl ether type epoxy resin, biphenol glycidyl ether type epoxy obtained by reaction of phenols or alcohols with chloromethyloxirane. Glycidyl ether type epoxy resins such as resins, bixylenol glycidyl ether type epoxy resins, cresol novolac type epoxy resins, salicylaldehyde type epoxy resins, glycidyl ester type epoxy resins obtained by reaction of carboxylic acids with chloromethyloxirane, amines Glycidylamine type epoxy resin obtained by reaction with chloromethyloxirane, internal epoxy obtained by oxidation of double bond Resins, heterocyclic epoxy resins such as triglycidyl isocyanurate. These details are described, for example, in “Epoxy resin handbook” edited by Masaki Shinbo (published by Nikkan Kogyo Shimbun 1987).

  Of these, preferred are glycidyl ether type epoxy resins and heterocyclic type epoxy resins, and more preferred are biphenol glycidyl ether type epoxy resins, bixylenol glycidyl ether type epoxy resins, cresol novolac epoxy resins and salicylaldehyde types. It is an epoxy resin.

  Moreover, it is also possible to use brominated epoxy resin as (C) epoxy resin. Use of brominated epoxy resin provides flame retardancy. As the brominated epoxy resin, known ones having one or more bromine atoms in one molecule can be used. As the brominated epoxy resin, those represented by the following general formula (2) and the following general formula (3) can be preferably used.

  In the general formula (2), X is selected from a single bond, a methylene group, an ethylidene group, an isopropylidene group and a sulfonyl group, preferably a methylene group or an isopropylidene group, and most preferably an isopropylidene group. . In the general formula (2), m is 0 or an integer of 1 to 10.

  In the general formula (3), Z is selected from a hydrogen atom or a 2,3-epoxypropyl group, and at least one Z is a 2,3-epoxypropyl group. In the general formula (3), q is 0 or an integer of 1 to 10.

  Specific examples of the brominated epoxy resin used in the present invention include diglycidyl ether of tetrabromobisphenol A, diglycidyl ether of tetrabromobisphenol F, diglycidyl ether of tetrabromobisphenol A ethylene oxide adduct, tetrabromo Examples thereof include diglycidyl ether of bisphenol F ethylene oxide adduct and glycidyl ether of brominated novolac type phenol resin. These brominated epoxy resins may be used alone or in combination. Of these, bisphenol-type brominated epoxy resins such as tetrabromobisphenol A diglycidyl ether, and most preferably tetrabromobisphenol A diglycidyl ether.

  In this invention, the usage-amount of (C) epoxy resin is 1-70 mass% in (II) photosensitive layer of this invention, Preferably it is 3-40 mass%, Most preferably, it is 5-20 mass%. (C) When the amount of the epoxy resin used is less than 1% by mass, the heat resistance may decrease, and when it exceeds 70% by mass, the developability and storage stability may decrease.

  Moreover, when using brominated epoxy resin as (C) epoxy resin, the usage-amount is (II) photosensitive layer normally 3.0-25.0 mass%, Preferably it is 5.0-20.0 mass%, More preferably, 7.0- 15.0% by weight. If the amount of brominated epoxy resin used is less than 3.0% by mass, the effect on the flame retardancy may not be recognized, and if it exceeds 25.0% by mass, the heat resistance may deteriorate and the alkali developability may decrease. .

  In the present invention, the photosensitive composition preferably further contains (D) a photocurable monomer or oligomer in addition to (A) to (C). These are added for the purpose of adjusting the viscosity of the photosensitive composition or adjusting physical properties such as heat resistance and flexibility when the photosensitive composition is a cured product. The (D) photocurable monomer or oligomer is not particularly limited as long as it is a compound that is polymerized by the photopolymerization initiator (B), and known ones can be used alone or in combination.

  (D) Specific examples of the photocurable monomer or oligomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) ) Acrylate, tert-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, stearyl Alkyl (meth) acrylates such as (meth) acrylate; cyclohexyl (meth) acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, Cycloaliphatic (meth) acrylates such as dicyclopentenyloxyethyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate, phenyl carbitol (meth) acrylate, nonylphenyl (meth) acrylate, nonylphenyl carbitol Aromatic (meth) acrylates such as (meth) acrylate and nonylphenoxy (meth) acrylate; 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, butanediol mono (meth) acrylate , Glycerol (meth) acrylate, phenoxyhydroxypropyl (meth) acrylate, polyethylene glycol (meth) acrylate, glycerol di (meth) acrylate, etc. (Meth) acrylate having a hydroxyl group; (meth) acrylate having an amino group such as 2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, 2-tert-butylaminoethyl (meth) acrylate; Examples thereof include mono (meth) acrylates such as methacrylate having a phosphorus atom such as methacryloxyethyl phosphate, bis-methacryloxyethyl phosphate, methacryloxyethyl phenyl acid phosphate, and the like.

  Specific examples of the (D) photocurable monomer or oligomer include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene di (meth) acrylate, and polyethylene glycol. Di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,3-butanediol Dimethacrylates such as di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, bis-glycidyl (meth) acrylate; trimethylo Polyacrylates such as lepropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate; bisphenol S ethylene oxide 4 mol modified diacrylate, bisphenol A ethylene oxide 4 mol modified diacrylate, fatty acid modified penta Modified polyol poly (meth) acrylate such as erythritol diacrylate, trimethylolpropane propylene oxide 3 mol modified triacrylate, trimethylolpropane propylene oxide 6 mol modified triacrylate, polyester (meth) acrylate, urethane other than the above (A) (Meth) acrylate, epoxy (meth) acrylate other than the above (A), and the like.

  Further, (D) photocurable monomers or oligomers include isocyanuric acids such as bis (acryloyloxyethyl) monohydroxyethyl isocyanurate, tris (acryloyloxyethyl) isocyanurate, and ε-caprolactone-modified tris (acryloyloxyethyl) isocyanurate. Polyacrylates having a skeleton; polyester acrylates such as α, ω-diacryloyl- (bisethylene glycol) -phthalate and α, ω-tetraacryloyl- (bistrimethylolpropane) -tetrahydrophthalate; glycidyl (meth) acrylate; allyl (meta ) Acrylate; ω-hydroxyhexanoyloxyethyl (meth) acrylate; polycaprolactone (meth) acrylate; (meth) acryloyloxyethylphthale DOO; (meth) acryloyloxyethyl succinate; 2-hydroxy-3-phenoxypropyl acrylate; phenoxyethyl acrylate and the like can be used.

  Among these, preferred are (meth) acrylate having a hydroxyl group, urethane (meth) acrylate other than (A), and epoxy (meth) acrylate other than (A).

  The amount of the (D) photocurable monomer or oligomer used is usually 0.1 to 30% by mass, preferably 1.0 to 20% by mass, and particularly preferably 3.0 to 15% by mass in the photosensitive layer (II). %.

  The photosensitive composition may further contain (E) a curing reaction catalyst. (E) A curing reaction catalyst is a compound which accelerates | stimulates the reaction of epoxy groups, or the reaction of an epoxy group and a carboxyl group, and can use a well-known thing.

  Specific examples of the (E) curing reaction catalyst include amines, nitrogen-containing heterocyclic compounds, ammonium salts, and polyamides. Examples of amines include aliphatic and aromatic primary, secondary, and tertiary amines.

  Examples of primary or secondary amines among aliphatic amines include ethylenediamine, diethylenetriamine, triethylenetriamine, tetraethylenepentamine, triethylenetetramine, dimethylaminopropylamine, mensendiamine, N-aminoethylethanolamine. Polyethylene glycol bis (2-aminoethyl) ether, bis (hexamethylene) triamine, 1,3,6-trisaminomethylhexane, m-xylylenediamine, 3,9-bis (3-aminopropyl) spiro-2 4,8,10-tetraoxaundecane.

  Examples of tertiary amines among aliphatic amines include triethylamine, tri-n-propylamine, tri-n-butylamine, triethanolamine, N, N-dimethyloctylamine, N, N-dimethylbenzylamine, 2 , 4,6-tris (dimethylaminophenol), N, N, N ′, N′-tetramethylethylenediamine and the like.

  Examples of aromatic amines include metaphenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, bis [4- (4-aminophenoxy) phenyl] ether, 2,2-bis [4- ( 4-aminophenoxy) phenyl] propane, diaminodiphenylsulfone, m-aminophenol and the like.

  Other examples of amines include polyamines such as tetramethylguanidine, dicyandiamide, urea, urea derivatives, and polybasic hydrazides; organic acid salts and / or epoxy adducts thereof; and amine complexes of boron trifluoride. It is done.

  Nitrogen-containing heterocyclic compounds include pyridines such as pyridine, picoline, and lutidine; imidazole, 2-ethyl-4-methylimidazole, N-benzyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate Imidazoles such as 2-methylimidazolium isocyanurate; morpholines such as N-methylmorpholine and N-ethylmorpholine; 1,4-diazabicyclo [2,2,2] octane, 1,8-diazabicyclo [5, 4,0] Undec-7-ene and the like are exemplified.

  Another example of the nitrogen-containing heterocyclic compound is a triazine compound. Specifically, melamines such as melamine, N-ethylenemelamine, N, N ′, N ″ -triphenylmelamine, hexa (N-methyl) melamine; ethyldiamino-S-triazine, 2,4-diamino- Guanamines such as S-triazine, 2,4-diamino-6-xylyl-S-triazine, acetoguanamine, benzoguanamine; cyanuric acid, isocyanuric acid, trimethyl cyanurate, trismethyl isocyanurate, triethyl cyanurate, trisethyl isocyanurate And cyanuric acids such as tri (n-propyl) cyanurate, tris (n-propyl) isocyanurate, diethyl cyanurate, N, N′-diethyl isocyanurate, methyl cyanurate, methyl isocyanurate and the like.

  As ammonium salts, tetramethylammonium chloride, tetraethylammonium chloride, benzyltrimethylammonium chloride, octyltrimethylammonium chloride, decyltrimethylammonium chloride, tetradecyltrimethylammonium chloride, phenyltributylammonium chloride, tetramethylammonium bromide, tetraethylammonium bromide, benzyl Examples include quaternary ammonium salts such as trimethylammonium bromide, octyltrimethylammonium bromide, decyltrimethylammonium bromide, tetradecyltrimethylammonium bromide, and phenyltributylammonium bromide.

  Examples of the polyamides include polyaminoamides having primary and secondary amino groups obtained by condensation reaction of polyamines such as diethylenetriamine and triethylenetetraamine with dimer acid.

  The amount of the (E) curing reaction catalyst used is usually less than 1.0% by mass in the photosensitive composition for dry film of the present invention, preferably 0.9% by mass or less, more preferably 0.8% by mass or less, and still more preferably. Is 0.7% by mass or less, more preferably 0.6% by mass or less, particularly preferably 0.5% by mass or less, and most preferably 0.4% by mass or less.

  The photosensitive composition having (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator, and (C) an epoxy resin as essential components used in the present invention is prepared by using the above-described components in the usual manner. It can be manufactured by mixing. The mixing method is not particularly limited, and a part of the components may be mixed and then the remaining components may be mixed, or all the components may be mixed at once. Further, an organic solvent may be added to the photosensitive composition for viscosity adjustment. By adjusting the viscosity, it becomes easy to apply onto the object by roller coating, bar coating, die coating, curtain coating or the like. Examples of the organic solvent include ketone solvents such as ethyl methyl ketone, methyl isobutyl ketone, and cyclohexanone; ester solvents such as ethyl acetoacetate, γ-butyrolactone, and butyl acetate; alcohol solvents such as butanol and benzyl alcohol; carbitol acetate, Solvents of cellosolve such as methyl cellosolve acetate, carbitols and their esters and ether derivatives; Amides of solvents such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone; Dimethyl sulfoxide Phenol compounds such as phenol and cresol; nitro compound solvents; toluene, xylene, hexamethylbenzene, cumene aromatic solvents; aromatics and alicyclics composed of hydrocarbons such as tetralin, decalin, dipentene, etc. And the like solvents. One kind or a combination of two or more kinds can be used. The amount of these organic solvents used is arbitrary, but in (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator, and (C) a photosensitive composition having an epoxy resin as essential components, usually It is 10-70 mass%, Preferably it is 20-65 mass%, Most preferably, it is 30-60 mass%.

  The photosensitive composition containing (II) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator, and (C) an epoxy resin as essential components for forming the photosensitive layer (II) as necessary. Additives such as thermal polymerization inhibitors, antifoaming agents, leveling agents, adhesion promoters, inorganic or organic fillers can be added. Examples of the thermal polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol, phenothiazine and the like. The antifoaming agent is used to eliminate bubbles generated during coating and curing, and specifically includes an acrylic or silicone surfactant. The leveling agent is used to lose unevenness on the surface of the film that occurs during coating, and specific examples include acrylic and silicon surfactants. Examples of the adhesion imparting agent include imidazole, thiazole, triazole, and silane coupling agents. Specific examples of the inorganic filler include talc, barium sulfate, barium titanate, silica, alumina, clay, magnesium carbonate, calcium carbonate, aluminum hydroxide, magnesium hydroxide, silicate compound and the like. Specific examples of the organic filler include silicon resin, silicon rubber, and fluorine resin.

  In the present invention, a protective film (III) may be further laminated on the surface opposite to the surface on which the support film of the photosensitive layer (II) is laminated. (III) The protective film is formed by molding an arbitrary polymer into a film, and may be a single layer film or a multilayer film. Further, it may be the same as or different from the above (I) support film.

  (III) Specific examples of the protective film include polypropylene films such as propylene homopolymer film, propylene random copolymer film, propylene block copolymer film, low density polyethylene film, linear low density polyethylene film and high density polyethylene. Examples include polyethylene films such as films, polyester films such as polyamide films, polyethylene terephthalate films, and polyethylene naphthalate films. Among these, a polypropylene film, a polyethylene film and a polyester film are preferable, and a biaxially stretched polypropylene film, a low density polyethylene film, a linear low density polyethylene film and a polyethylene terephthalate film are particularly preferable.

  There is no restriction | limiting in particular in the thickness of the (III) protective film used for this invention, Usually, it is 0.1-200 micrometers, Preferably it is 1.0-100 micrometers, More preferably, it is 5.0-80 micrometers, More preferably, it is 5.0-60 micrometers, More preferably, it is 8.0. -50 μm, particularly preferably 10.0-45 μm, most preferably 10.0-40 μm.

  The (III) protective film used in the present invention may contain 0.01 to 0.70% by mass of an antiblocking agent. The kind and addition amount of an antiblocking agent are the same as that of the said (I) support film. Further, the (III) protective film of the present invention may be subjected to various treatments such as corona treatment.

  Furthermore, the (III) protective film used in the present invention may have a release agent layer formed on the surface facing the photosensitive layer. The release agent layer is a known release agent such as silicone, silicone surfactant, fluorine surfactant, polyalkylene glycol surfactant, polyalkylene amine surfactant, acrylic surfactant, hydrocarbon wax, etc. It is formed by applying or laminating. Among these release agents, those containing silicone as a main component are preferable, and the content in the release agent is 50% by mass or more, preferably 70% by mass or more. In particular, when a polyester film is used as the (III) protective film, it is preferable to form a release agent layer on the surface of the (III) protective film facing the (II) photosensitive layer.

  Next, the manufacturing method of the photosensitive dry film roll of this invention is demonstrated. The dry film roll of the present invention is produced by the following steps (A) to (E).

(I) a step of (I) feeding out the support film from the (I) support film wound up in a roll;
(B) A photosensitive composition comprising (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator and (C) an epoxy resin as an essential component is continuously formed on the drawn (I) support film. Step of applying automatically,
(C) (I) A photosensitive composition having (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator and (C) an epoxy resin as essential components applied on the support layer film is dried. (II) forming a photosensitive layer,
(D) a step of drawing out a protective film (III) from a protective film wound up in a roll shape and pasting it on the photosensitive layer (II) to form a dry film resist;
(E) A step of winding the formed dry film resist into a roll.

  Here, in the step (A), first, the (I) support film is unwound from the (I) support film wound up in a roll shape. At the end of the extended support film, the photosensitive composition is applied, that is, the region where the step (b) is performed, the region where the drying, step (c) is performed, and the bonding of the protective film, ie the step (d). It is fixed to the winding core in the area where the step (e) is performed via the area to be cut. Next, the support film is continuously unwound by rotating the winding core with a constant tension and winding the supporting film around the winding core.

  In step (b), (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator, and (C) an epoxy resin are essential components on (I) the support film that has been drawn out as described above. The photosensitive composition is applied continuously. The application method is arbitrary, but is usually performed using a doctor blade, a comma coater or a die coater.

  In step (c), (I) a photocurable resin having a carboxyl group applied on the support film, (B) a photopolymerization initiator and (C) a photosensitivity comprising epoxy resin as essential components. The composition is dried to form (II) a photosensitive layer. The drying method is arbitrary, and drying is performed at a temperature of about 40 to 150 ° C. with hot air or infrared rays.

  In the step (d), the (III) protective film is unwound from the protective film roll wound up in a roll shape, and is bonded onto the (II) photosensitive layer. (III) The unwinding of the protective film is performed by rotating the protective film roll so as to maintain a constant rotational speed or a constant tension. The rotation of the roll may be directly driven, or may be indirectly driven by taking out the (III) protective film that has been fed out. Bonding can be carried out by any method, but usually (I) a laminate composed of a support film and a photosensitive layer formed on the support film and a protective film layer are rolled, preferably between hot rolls. This is done by passing it through. The pressure of the roll is arbitrary, and the temperature of the roll is also arbitrary, but is usually room temperature to 100 ° C.

  In the step (e), the dry film resist formed in the steps (a) to (d) is wound into a roll. The winding is usually performed by winding on a winding core made of paper, metal, or any plastic such as polyvinyl chloride, polystyrene, polyethylene, acrylonitrile-butadiene-styrene resin (ABS resin).

  Although there is no restriction | limiting in particular in the diameter of a winding core, In order to make the diameter of a roll small, it is preferable that the diameter of a winding core is small, and is 1-10 cm in this case, Preferably it is 1-4 cm.

  On the other hand, in order to reduce the stress applied to the roll-shaped dry film, it is desirable that the diameter of the winding core is large. In this case, the diameter of the winding core is 10 to 30 cm, and preferably 11 to 20 cm.

  Hereinafter, the present invention will be described in more detail with reference to production examples of polyethylene terephthalate films, synthesis examples of photocurable resins, and examples, but the present invention is not limited thereto. In addition, in the following examples, a part represents a mass part and% represents mass%.

Production of polyethylene terephthalate film:
A high-purity terephthalic acid (332 g), ethylene glycol (136 g), and titanium tetrabutoxide (0.086 g) were charged into an autoclave, and the generated water was constantly distilled out of the system in a nitrogen atmosphere at a pressure of 0.17 MPa and 255 ° C. for 2 hours with stirring. After the reaction, the temperature was lowered to 250 ° C. and the reaction was further continued for 6 hours. Further, 0.62 g of a solution in which germanium dioxide and ethylene glycol were mixed at a weight ratio of 1:10 was added and stirred for 20 minutes. Further, 0.06 g of phosphoric acid was added and reacted for 1 hour. Thereafter, the temperature was raised to 280 ° C. over 1 hour, the inside of the system was reduced to 1 torr, and further reacted for 4 hours, and unreacted ethylene glycol was distilled out of the system. The polyethylene terephthalate thus obtained by liquid phase polymerization was further dried at 140 ° C. for 15 hours in a nitrogen atmosphere and crystallized, and then subjected to solid state polymerization at 205 ° C. for 15 hours in a nitrogen atmosphere. Next, 100 g of the obtained polyethylene terephthalate was immersed in 130 g of 90 ° C. distilled water for 4 hours for water treatment, and then dried in nitrogen at 140 ° C. for 14 hours. The intrinsic viscosity of the obtained polyethylene terephthalate measured in o-chlorophenol at 25 ° C. was 0.80 dl / g.

  After adding the anti-blocking agent shown in Table 1 to the polyethylene terephthalate obtained above and melt-kneading it with a co-rotating twin-screw extruder with a cylinder temperature of 270 ° C., the film was formed at 285 ° C. with an extruder equipped with a T-die. To obtain a polyethylene terephthalate film.

Measurement of oligomer content:
A test piece of 50 mm × 50 mm was cut out from the support film, and its mass was accurately weighed (W1). Subsequently, this test piece was put into a 300 ml flask equipped with a reflux condenser, and 150 ml of xylene dried with molecular sieves was put into the flask. The flask was purged with nitrogen and then heated to reflux for 10 hours. After cooling the flask, the test piece was taken out and dried, its mass was accurately weighed (W2), and the oligomer content was calculated by the following formula.
Oligomer content (% by mass) = {(W1-W2) / W1} × 100

Synthesis Example 1: Synthesis of photocurable resin (A) After 400 parts of bisphenol F type solid epoxy resin (manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 800) was dissolved in 925 parts of epichlorohydrin and 462.5 parts of dimethyl sulfoxide, Under stirring at 70 ° C., 81.2 parts of 98.5% NaOH was added over 100 minutes. After the addition, the reaction was further carried out at 70 ° C. for 3 hours. Next, most of the excess unreacted epichlorohydrin and dimethyl sulfoxide were distilled off under reduced pressure, and the reaction product containing the by-product salt and dimethyl sulfoxide was dissolved in 750 parts of methyl isobutyl ketone, and further 10 parts of 30% NaOH was added to 70 ° C. For 1 hour. After completion of the reaction, washing with 200 parts of water was performed twice. After oil-water separation, methyl isobutyl ketone was recovered from the oil layer by distillation to obtain 370 parts of an epoxy resin (a-1) having an epoxy equivalent of 290.

  2900 parts (10 equivalents) of the epoxy resin (a-1) obtained above, 720 parts (10 equivalents) of acrylic acid, 2.8 parts of methylhydroquinone, and 1950 parts of carbitol acetate were added, heated to 90 ° C., stirred, and the reaction mixture Was dissolved. Next, the reaction solution was cooled to 60 ° C., charged with 16.7 parts of triphenylphosphine, heated to 100 ° C., and reacted for about 32 hours to obtain a reaction product having an acid value of 1.0 mgKOH / g. Next, 1480 parts (9 equivalents) of tetrahydrophthalic anhydride and 423 parts of carbitol acetate were added to this, heated to 95 ° C., reacted for about 6 hours, and after cooling, solids with a solid acid value of 100 mgKOH / g Thus, a carboxyl group-containing photocurable resin (A-1) having a concentration of 65% was obtained. The viscosity (25 ° C.) of the obtained (A-1) was 320 poise.

Synthesis example 2: Synthesis of photocurable resin (A-2) Polycaprolactone diol (manufactured by Daicel Chemical Industries, Ltd., PLACEL 212, molecular weight 1250) is used as a polymer polyol in a reaction vessel equipped with a stirrer, a thermometer, and a condenser. 3750 g, 402 g of dimethylolpropionic acid as a dihydroxyl compound having a carboxyl group, 1554 g of polyisocyanate and isophorone diisocyanate, 238 g of 2-hydroxyethyl acrylate as a (meth) acrylate having a hydroxyl group, and p-methoxy 1.0 g each of phenol and di-t-butyl-hydroxytoluene was added. The mixture was heated to 60 ° C. with stirring and stopped, and 1.6 g of dibutyltin dilaurate was added. When the temperature in the reaction vessel starts to decrease, the mixture is heated again and stirred at 80 ° C. to confirm that the isocyanate group absorption spectrum (2280 cm ⁻¹ ) has disappeared in the infrared absorption spectrum. A group-containing photocurable resin (A-2) was obtained. The number average molecular weight of the obtained photocurable resin (A-2) was 25,000, and the acid value was 40 mgKOH / g.

Example 1:
(1) Production of photosensitive composition After blending each component constituting the main agent composition and the curing agent composition in the proportions shown in Table 1, the mixture is mixed twice by a three-roll mill, and the main agent composition and the curing agent composition are mixed. A product was prepared. Next, the main component composition, the curing agent composition, and the organic solvent are mixed and stirred with a stirrer at 2000 rpm for 5 minutes to (A) a photocurable resin having a carboxyl group, and (B) initiation of photopolymerization. A photosensitive composition containing an agent and (C) an epoxy resin as essential components was obtained (Formulation 1).

(2) Manufacturing process of photosensitive dry film roll for printed wiring board protective film (I)
A polyethylene terephthalate film (which is a support film and is the (I) polymer film of the present invention) was fed out from a roll of polyethylene terephthalate film at a speed of 0.5 m / min. The feeding was performed by fixing the end of the support film unwound from the roll to the core and rotating the core.

Process (b)
The photosensitive composition (IV) produced according to Production Example 1 was applied on the support film continuously drawn out in the step (ii) using a comma coater.
Process (C)
Next, (I) a photosensitive layer was formed by passing the photosensitive composition coated on (I) the support film through a hot-air drying oven (furnace length in the film moving direction, 2 m) set at 85 ° C. The film thickness of the photosensitive layer (II) after drying was 36 μm.

Process (d)
Furthermore, on the (II) photosensitive layer formed above, a polyethylene terephthalate film (which is a protective film and (III) the second polymer film of the present invention) is heated by a hot roll set at 55 ° C. Pasted.
Process (e)
The dry film formed by laminating the protective film produced a photosensitive dry film roll by winding it around the core to which the support film was fixed.

  Thereafter, while feeding out the dry film roll, both side ends of the unwound dry film were trimmed and removed, and the trimmed dry film was wound around another winding core to obtain a dry film roll again. The dry film roll was stored at room temperature for 3 days and then evaluated according to the following. The results are shown in Table 2.

(3) Evaluation of blocking property When the dry film was drawn out from the photosensitive dry film roll, the presence or absence of adhesion between the protective film and the support film was observed. The case where no adhesion was observed was marked with ◯, and the case where adhesion was observed was marked with ×.

(4) Evaluation of adhesion When the dry film was drawn out from the photosensitive dry film roll, the presence or absence of peeling between the photosensitive layer and the protective film or between the photosensitive layer and the support film was observed. The case where peeling was not observed was marked with ◯, and the case where peeling was seen was marked with x.

(5) Evaluation of bubbles remaining The protective film of the photosensitive dry film resist was peeled off, and a copper circuit pattern with a line and space of 100 μm / 100 μm was formed on one side with a vacuum laminator (V-130 manufactured by Nichigo Morton Co., Ltd.) at 60 ° C. A printed wiring board was manufactured by laminating a circuit pattern on a substrate (10 cm in length × 5 cm in width, copper foil: 17 μm thick, base material: 50 μm thick polyimide film). The obtained printed wiring board was visually observed for the presence of bubbles.

(6) Measurement of photosensitivity Polyimide in which the protective film of the photosensitive dry film resist is peeled off and copper foil (thickness 35 μm) is laminated on one side by a vacuum laminator (V-130 manufactured by Nichigo-Morton Co., Ltd.) at 60 ° C. The laminate was prepared by laminating on a copper foil of a printed circuit board (Ube Kosan Co., Ltd., Upicel (registered trademark) N) made of a film (thickness: 50 μm). This laminate was exposed to ultraviolet rays through a photomask (21-step density tablet, manufactured by Hitachi Chemical Co., Ltd.) (ultra-high pressure mercury lamp, main wavelength 365 nm, 700 mJ / cm ² ), and then 1 ° C. at 30 ° C. Development was performed with a mass% sodium carbonate aqueous solution, followed by washing with 30 ° C. water. After this operation, the number of steps that were normally cured was taken as the value of photosensitivity.

(7) Evaluation of solder heat resistance The cover film of the said photosensitive dry film was peeled off, and it laminated on the copper of the copper clad laminated board with the 60 degreeC vacuum laminator (made by Nichigo Morton Co., Ltd.). Next, the photosensitive layer of this laminate was exposed with an ultrahigh pressure mercury lamp through a photomask having a checkered pattern of 5 mm × 5 mm, and the exposed photosensitive layer was developed with a 1% aqueous sodium carbonate solution. Then, the laminated body which has a checkered resist pattern was obtained by heat-curing for a time of Table 1 time in 150 degreeC oven.

  After the test piece prepared according to the above was floated in a solder bath at 260 ° C. for 10 seconds so that the resist surface was in contact with the solder, the presence or absence of swelling and peeling of the resist film was evaluated. These operations were repeated as one cycle, and the number of cycles in which no swelling or peeling of the resist film was observed was used as an index of solder heat resistance.

(8) Pressure cooker resistance The printed wiring board manufactured according to the following is left in a container (HAST TPC-412-MD, manufactured by Tabai Co., Ltd.) maintained at 121 ° C., 2 atm and relative humidity 100% for 100 hours, The appearance change and the insulation resistance test were evaluated according to the following.

(9) Manufacture of printed wiring board The cover film of the above-mentioned photosensitive dry film is peeled off, and a commercially available substrate (IPC standard, IPC-C (comb pattern)) using a vacuum laminator (manufactured by Nichigo Morton Co., Ltd.) at 60 ° C. Laminated on top. Next, this laminate was exposed with an ultrahigh pressure mercury lamp, and the support film was peeled off, followed by thermosetting in an oven at 150 ° C. for 60 minutes to obtain a printed wiring board.

(10) Change in appearance Judgment was made according to the following criteria.
◯: Floating on the cured film made of the photosensitive layer, peeling off, and no surface whitening.
(Triangle | delta): It floats in a part of cured film which consists of photosensitive layers, peels, and surface whitening is seen.
X: It floats on the whole surface of the cured film which consists of a photosensitive layer, peels, and surface whitening is seen.

(11) Electrical insulation After 100V DC voltage is applied to the circuit of the printed wiring board obtained above according to JIS C5012 and kept for 1 minute, the insulation resistance value is measured with an electrical insulation meter with the voltage applied. It was. The measurement was performed before and after the PCT (Pressure Cooker Test) test, and the determination was made according to the following criteria.

A: The insulation resistance value after the PCT test is 1/100 or more of the insulation resistance value before the PCT test.
A: The insulation resistance value after the PCT test is less than 1/100 to 1/1000 or more of the insulation resistance value before the PCT test.
Δ: The insulation resistance value after the PCT test is less than 1/1000 to 1/10000 or more of the insulation resistance value before the PCT test,
X: The insulation resistance value after the PCT test is less than 1/10000 of the insulation resistance value before the PCT test.

Examples 2-8:
A photosensitive dry film was obtained in the same manner as in Example 1 except that the support film, protective film, and antiblocking agent were as shown in Table 2. The results are shown in Table 2.

Comparative Examples 1-4:
A photosensitive dry film was obtained in the same manner as in Example 1 except that the addition amount of the antiblocking agent was changed to the value shown in Table 2. The evaluation results are shown in Table 2.

Reference example 1:
In Comparative Example 1, the same procedure as in Example 1 was performed, except that the dry film was cut into single sheets without being wound into a roll, and 100 sheets were stacked and stored. The results are shown in Table 2.

Examples 9-16:
In the production of polyethylene terephthalate, a support film was obtained in the same manner as in Example 1 except that the water treatment was performed for 2 hours. Using this support film, a photosensitive dry film was obtained in the same manner as in Example 1 except that the protective film and the antiblocking agent were as shown in Table 2. The results are shown in Table 2.

Comparative Examples 5-9:
In production of polyethylene terephthalate, a support film was obtained in the same manner as in Example 1 except that water treatment was not performed. Using this support film, a photosensitive dry film was obtained in the same manner as in Example 1 except that the protective film and the antiblocking agent were as shown in Table 2. The results are shown in Table 2.

Examples 17-26:
As a photosensitive composition comprising as essential components a support film, a protective film, an antiblocking agent, and (IV) (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator, and (C) an epoxy resin, The same procedure as in Example 1 was performed except that the formulation shown in Table 2 was used. The results are shown in Table 2.

Claims (15)

  (I) A dry film in which (II) a photosensitive layer is laminated on a support film, wherein the (I) support film is a polyester film having an oligomer content of 1.0% by mass or less, and an antiblocking agent 0.01 to A photosensitive dry film for a printed wiring board protective film, comprising 0.50% by mass.   The photosensitive dry film for a printed wiring board protective film according to claim 1, wherein the polyester film is a polyethylene terephthalate film.   3. The photosensitive dry film for a printed wiring board protective film according to claim 1 or 2, wherein (II) a protective film is laminated on the surface of the photosensitive layer opposite to the surface on which (I) the support film is laminated. .   (III) The photosensitive dry film for a printed wiring board protective film according to claim 3, wherein the protective film is a polyester film.   The photosensitive dry film for a printed wiring board protective film according to claim 4, wherein the polyester film is a polyethylene terephthalate film.   The photosensitive dry film for a printed wiring board protective film according to claim 5, wherein (III) the protective film has a release agent layer on the surface facing the photosensitive layer (II).   The photosensitive dry film for a printed wiring board protective film according to claim 6, wherein the release agent layer contains silicone as a main component.   (III) The protective dry film for a printed wiring board protective film according to claim 3, wherein the protective film is a polyolefin film.   The photosensitive dry film for a printed wiring board protective film according to claim 8, wherein the polyolefin film is a low-density polyethylene film or a polypropylene film.   (II) The photosensitive layer is formed from a photosensitive composition containing (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator and (C) an epoxy resin as essential components. The photosensitive dry film for printed wiring board protective films as described in any one of 1-9.   The photosensitive dry film for a printed wiring board protective film according to claim 10, wherein (A) the photocurable resin having a carboxyl group is an epoxy (meth) acrylate resin having a carboxyl group. An epoxy (meth) acrylate resin having a carboxyl group is represented by the following general formula (1):

(In the formula, X represents a single bond, a methylene group, an ethylidene group, an isopropylidene group, or a sulfonyl group, Y represents a hydrogen atom or a 2,3-epoxypropyl group, n is an integer of 1 to 10, When n is 1, Y represents a 2,3-epoxypropyl group. When n is 2 to 10, n X and Y may be the same or different, but at least one Y is 2, Represents a 3-epoxypropyl group.)
The product obtained by reacting the polybasic acid anhydride (c) with the reaction product of the bisphenol type epoxy resin (a) and the unsaturated group-containing monocarboxylic acid (b) represented by formula (11). Photosensitive dry film for printed wiring board protective film.   The photosensitive composition containing (A) a photocurable resin having a carboxyl group, (B) a photopolymerization initiator, and (C) an epoxy resin as an essential component, further comprising (D) a photocurable monomer or oligomer. The photosensitive dry film for printed wiring board protective films as described in any one of 10-12.   The photosensitive dry film roll for printed wiring board protective films which made the photosensitive dry film for printed wiring board protective films as described in any one of Claims 1-13 a roll form. At least the following steps (a) to (e):
(I) a step of (I) feeding out the support film from the (I) support film wound up in a roll;
(B) a step of continuously applying the photosensitive composition onto the drawn out (I) support film;
(C) (I) drying the photosensitive composition coated on the support film, and (II) forming a photosensitive layer;
(D) a step of drawing out a protective film (III) from a protective film wound up in a roll shape and pasting it on the photosensitive layer (II) to form a dry film resist;
(E) a step of winding the formed dry film resist into a roll,
And (I) the support film is a polyester film having an oligomer content of 1.0% by mass or less, and contains 0.01 to 0.50% by mass of an antiblocking agent. Film roll manufacturing method.