JP5739209B2 - Novel photosensitive resin composition and use thereof - Google Patents

Description

  This invention is excellent in tack-free property after drying of the coating film and has photosensitivity so that it can be finely processed. The resulting cured film is excellent in flexibility, flame retardancy and electrical insulation reliability, and is a substrate after curing. The present invention relates to a photosensitive resin composition, a resin film, an insulating film, and a printed wiring board with an insulating film.

  Polyimide resins are widely used in electrical and electronic applications because of their excellent heat resistance, electrical insulation reliability, chemical resistance, and mechanical properties. For example, it is used to form insulating films and protective coatings on semiconductor devices, base materials such as flexible circuit boards and integrated circuits, surface protective materials, and further, interlayer insulating films and protective films for fine circuits. .

  In particular, when used as a surface protection material for a flexible circuit board, a coverlay film obtained by applying an adhesive to a molded body such as a polyimide film has been used. When bonding this coverlay film on a flexible circuit board, there is a method in which an opening is provided in advance by a method such as punching in a terminal portion of a circuit or a joint portion with a component, and after aligning, a method of thermocompression bonding by a hot press or the like is used. It is common.

  However, it is difficult to provide a high-accuracy opening in a thin coverlay film, and since the alignment at the time of lamination is often performed manually, the positional accuracy is poor and the workability of the lamination is also poor. The cost was high.

  On the other hand, a solder resist or the like may be used as a surface protection material for a circuit board. In particular, a solder resist having a photosensitive function is preferably used when fine processing is required. As this photosensitive solder resist, a photosensitive resin composition mainly composed of acid-modified epoxy acrylate, epoxy resin, or the like is used. This photosensitive solder resist is excellent in electrical insulation reliability as an insulating material, but is bent. Therefore, when it is laminated on a thin and flexible circuit board such as a flexible circuit board, the warpage of the board becomes large and it is difficult to use it for a flexible circuit board. Further, the flame retardancy is poor, and when a flame retardant is added for the purpose of imparting flame retardancy, there are problems such as deterioration in physical properties and contact failure due to bleeding out from the cured film and process contamination.

  As this photosensitive solder resist, various proposals that can exhibit flexibility and flame retardancy have been made.

  For example, a photosensitive resin composition has been proposed that is excellent in flexibility and solder heat resistance, has good sensitivity and resolution, and can easily form a fine pattern of a heat-resistant protective film (see, for example, Patent Document 1). ).

  On the other hand, one of the important characteristics when carrying out the photosensitive solder resist processing is that the coating film surface is less sticky (tack-free) after the coating film is applied and the solvent is dried. This prevents the photomask from sticking to the coating film when it is irradiated with UV light by placing a photomask necessary for fine pattern formation on the surface of the coating film. This is an important characteristic for preventing the circuit boards from sticking to each other when the boards are stacked.

  As a method of improving the tack-free property after drying the coating film of this photosensitive solder resist, a technique of adding an inorganic filler to provide unevenness on the coating film surface is used, but the cured film is brittle because the inorganic filler is hard. Thus, there were problems such as generation of cracks and peeling from the substrate.

  Therefore, a high-performance photocurable liquid solder resist ink composition has been proposed that is highly sensitive and excellent in tack-free and developability of the coating film, and does not cause adhesion degradation or peeling due to cracking or volume shrinkage. (For example, refer to Patent Document 2).

JP 2000-241969 A Japanese Patent Laid-Open No. 9-137109

  In the above-mentioned patent documents, various methods for solving the problems of the photosensitive solder resist are proposed. However, since the photosensitive resin composition described in Patent Document 1 contains a urethane compound having an ethylenically unsaturated bond containing a flexible skeleton and an aromatic phosphate ester, sensitivity, resolution, folding resistance, difficulty Although it is excellent in flammability, there are problems that electrical insulation reliability, bleeding out from a cured film, and stickiness after drying of the coating film are large and inferior in tack-free property. The ink composition for solder resist described in Patent Document 2 is excellent in tack-free coating film due to dispersion of polymer fine particles having a glass transition temperature of 20 ° C. or less, and adhesion due to generation of cracks and volume shrinkage. However, when used as an insulating protective film of a flexible printed wiring board, there is a problem that bending resistance and flame retardancy are poor and warpage is large.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that at least (A1) a resin containing substantially no radical polymerizable group in the molecule and containing a urethane bond and a carboxyl group, (A2) molecule A photosensitivity characterized in that it contains a radically polymerizable group and a urethane bond, (B) crosslinked polymer particles, (C) a thermosetting resin, and (D) a photopolymerization initiator. From the resin composition, it has excellent tack-free properties after drying the coating film and has photosensitivity, so it can be finely processed, and the resulting cured film has excellent flexibility, flame retardancy, and electrical insulation reliability. The knowledge which a photosensitive resin composition, a resin film, an insulating film, and a printed wiring board with an insulating film with a small board | substrate curvature were obtained was obtained, and based on these knowledge, this invention was achieved. This invention can solve the said subject with the photosensitive resin composition of the following novel structures.

  That is, the present invention comprises at least (A1) a resin that substantially does not contain a radical polymerizable group in the molecule and contains a urethane bond and a carboxyl group, and (A2) contains a radical polymerizable group in the molecule, A photosensitive resin composition comprising a resin containing a urethane bond, (B) crosslinked polymer particles, (C) a thermosetting resin, and (D) a photopolymerization initiator.

Moreover, in the photosensitive resin composition concerning this invention, it is preferable that the average particle diameter of the said (B) crosslinked polymer particle is 1-10 micrometers.
Moreover, in the photosensitive resin composition concerning this invention, the compounding quantity of the said (B) crosslinked polymer particle (A1) does not contain a radically polymerizable group substantially in a molecule | numerator, and a urethane bond and a carboxyl group are included. It is preferable that it is 30-100 weight part with respect to a total of 100 weight part of resin to contain and the resin containing (A2) radical polymerizable group in a molecule | numerator, and containing a urethane bond.

  Moreover, in the photosensitive resin composition concerning this invention, it is preferable that the said (B) crosslinked polymer particle is a crosslinked polymer particle containing a urethane bond in a molecule | numerator.

  Moreover, in the photosensitive resin composition concerning this invention, it is preferable to contain the (E) phosphorus flame retardant further.

  Moreover, in the photosensitive resin composition concerning this invention, it is preferable that the said (E) phosphorus flame retardant is a phosphinate.

  Moreover, in the photosensitive resin composition concerning this invention, it is preferable that the said (C) thermosetting resin is a polyfunctional epoxy resin.

  Moreover, the resin film concerning this invention is obtained by drying, after apply | coating the said photosensitive resin composition to the base-material surface.

  The insulating film according to the present invention is obtained by curing the resin film.

  The printed wiring board with an insulating film according to the present invention is formed by coating the insulating film on the printed wiring board.

  As described above, the photosensitive resin composition of the present invention comprises at least (A1) a resin that substantially does not contain a radical polymerizable group in the molecule and contains a urethane bond and a carboxyl group, and (A2) an intramolecular In this application, the resin composition includes a radically polymerizable group and a resin containing a urethane bond, (B) a crosslinked polymer particle, (C) a thermosetting resin, and (D) a photopolymerization initiator. The photosensitive resin composition of the invention is excellent in tack-free properties after drying of the coating film, and can be finely processed because it has photosensitivity, and the resulting cured film is excellent in flexibility, flame retardancy, and electrical insulation reliability The warpage of the substrate after curing is small. Therefore, the photosensitive resin composition of the present invention can be used for protective films of various circuit boards and exhibits excellent effects.

It is the schematic diagram which has measured the curvature amount of the film.

  Hereinafter, the present invention will be described in detail in the order of (I) the photosensitive resin composition and (II) the method of using the photosensitive resin composition.

(I) Photosensitive resin composition The photosensitive resin composition of the present invention is a resin containing at least (A1) a radically polymerizable group in the molecule and containing a urethane bond and a carboxyl group. A2) containing a radically polymerizable group in the molecule and containing a urethane bond, (B) a crosslinked polymer particle, (C) a thermosetting resin, and (D) a photopolymerization initiator. The photosensitive resin composition.

  Here, although the present inventors discovered that the photosensitive resin composition of this invention was excellent in various characteristics, it estimates that this may be based on the following reasons. That is, the resin that does not substantially contain a radically polymerizable group in the molecule as the component (A1) and contains a urethane bond and a carboxyl group does not substantially contain a radically polymerizable group. The distance between the cross-linking points of the cured film obtained from the photosensitive resin composition is increased, and since it contains a urethane bond having excellent flexibility, the flexibility is excellent, the warpage of the substrate after curing is small, and the carboxyl group in the molecule Therefore, the photosensitive resin composition containing this is excellent in the solubility to the aqueous alkali solution which is a developing solution at the time of forming a fine pattern. Further, by combining a urethane bond-containing resin containing a radically polymerizable group in the molecule that is the component (A1) and the component (A2), both flexibility and photosensitivity can be achieved at a high level. In addition, since the crosslinked polymer particles as the component (B) serve to provide unevenness on the surface of the coating film, the polymer particles are excellent in tack-free property after drying the coating film obtained from the photosensitive resin composition containing the polymer particle. Is soft and does not cause a decrease in flexibility of the coating film. Furthermore, since the polymer particles have a crosslinked structure, they are excellent in heat resistance and chemical resistance. Furthermore, surprisingly, in general, when the filler component is highly filled, the flexibility to withstand repeated bending is lowered, but by combining the components (A1), (A2), and (B), the photosensitivity is excellent. Nevertheless, the cured film obtained from the photosensitive resin composition containing these is very soft and excellent in fold resistance. This is because the affinity between the crosslinked polymer particles and the components (A1) and (A2) constituting the matrix of the cured film is better than the inorganic filler because the crosslinked polymer particles are organic fillers. It is speculated that the components (A1) and (A2) permeate into the interior, and that strong adhesiveness is obtained at the interface between the components (A1) and (A2) and the component (B).

  Hereinafter, (A1) a resin containing substantially no radical polymerizable group in the molecule and containing a urethane bond and a carboxyl group, and (A2) containing a radical polymerizable group in the molecule and containing a urethane bond. The mixing method of resin, (B) crosslinked polymer particle, (C) thermosetting resin, (D) photopolymerization initiator, (E) phosphorus flame retardant, other components, and photosensitive resin composition will be described. .

<(A1) Resin containing substantially no radical polymerizable group in the molecule and containing a urethane bond and a carboxyl group>
The resin having substantially no radical polymerizable group in the molecule (A1) of the present invention and containing a urethane bond and a carboxyl group is substantially free of radical polymerizable group in the molecule, and at least A polymer having a repeating unit containing one urethane bond and a repeating unit containing at least one carboxyl group and having a weight average molecular weight of 1,000 or more and 1,000,000 or less in terms of polyethylene glycol. .

  Here, the term “substantially free of radically polymerizable group in the molecule” means that the molecule may not contain any radically polymerizable group such as (meth) acryloyl group or vinyl group, and the effect of the present invention. If it is a range which does not impair expression of, you may contain. The range which does not impair the expression of the effect of the present invention means that the value determined by measuring the radical polymerizable group in the molecule of the component (A1) as an iodine value is less than 5. The iodine value is a value obtained by converting the amount of halogen bonded to 100 g of a sample into the number of g of iodine, and can be measured by a method defined in JIS K0070.

The molecular weight of the component (A1) of the present invention can be measured, for example, by the following method.
Equipment used: Tosoh HLC-8220GPC equivalent column: Tosoh TSK gel Super AWM-H (6.0 mm ID x 15 cm) x 2 guard columns: Tosoh TSK guard column Super AW-H
Eluent: 30 mM LiBr + 20 mM H3PO4 in DMF
Flow rate: 0.6 mL / min
Column temperature: 40 ° C
Detection conditions: RI: Polarity (+), response (0.5 sec)
Sample concentration: about 5 mg / mL
Standard product: PEG (polyethylene glycol)

  Controlling the weight average molecular weight within the above range is preferable because the alkali developability of the photosensitive resin composition, the flexibility of the resulting cured film, and the chemical resistance are excellent. When the weight average molecular weight is 1,000 or less, flexibility and chemical resistance may decrease, and when the weight average molecular weight is 1,000,000 or more, the alkali developability of the photosensitive resin composition decreases. , The viscosity may increase.

  The carboxyl group content of the component (A1) of the present invention can be measured as an acid value. The acid value of the component (A1) is preferably 50 to 200 mgKOH / g, and more preferably 50 to 150 mgKOH / g. When the acid value is less than 50 mgKOH / g, the alkali developability of the photosensitive resin composition may be reduced. When the acid value is more than 200 mgKOH / g, the hygroscopicity of the cured film may be increased and the electrical insulation reliability may be reduced. is there.

  The component (A1) of the present invention can be obtained by any reaction. For example, the following general formula (1)

(Wherein R ₁ represents a divalent organic group)
A diol compound represented by the following general formula (2)

(Wherein R ₂ represents a trivalent organic group)
A compound containing two hydroxyl groups and one carboxyl group represented by the following general formula (3):

(Wherein X ₁ represents a divalent organic group)
Is reacted with the diisocyanate compound represented by the following general formula (4):

(Wherein R ₁ represents a divalent organic group, R ₂ represents a trivalent organic group, X ₁ represents a divalent organic group, n represents an integer of 1 or more, and m represents an integer of 1 or more)
It is obtained as a structure containing a repeating unit containing a urethane bond represented by

  The diol compound is not particularly limited as long as it has the above structure. For example, ethylene glycol, diethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, Polyoxyalkylene such as alkylene diol such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and a random copolymer of tetramethylene glycol and neopentyl glycol A ring-opening addition reaction of diols, polyester diols obtained by reacting polyhydric alcohols and polybasic acids, polycarbonate diols having a carbonate skeleton, γ-butyllactone, ε-caprolactone, δ-valerolactone, etc. Polycaprolactone diol, bisphenol A, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, hydrogenated bisphenol A, ethylene oxide adduct of hydrogenated bisphenol A, propylene oxide adduct of hydrogenated bisphenol A, etc. These can be used alone or in combination of two or more.

  In particular, when a long-chain diol such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyalkylene diol, polyester diol, polycarbonate diol, or polycaprolactone diol is used, curing obtained by curing the photosensitive resin composition It is preferable in that the elastic modulus of the film is lowered and the flexibility and low warpage are excellent.

  The compound containing the two hydroxyl groups and one carboxyl group is not particularly limited as long as it has the above structure. For example, 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (2-hydroxyethyl) ) Propionic acid, 2,2-bis (3-hydroxymepropyl) propionic acid, 2,3-dihydroxy-2-methylpropionic acid, 2,2-bis (hydroxymethyl) butanoic acid, 2,2-bis (2 -Hydroxyethyl) butanoic acid, 2,2-bis (3-hydroxypropyl) butanoic acid, 2,3-dihydroxybutanoic acid, 2,4-dihydroxy-3,3-dimethylbutanoic acid, 2,3-dihydroxyhexadecanoic acid 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid Acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, etc. These can be used alone or in combinations of two or more.

  In particular, when a compound containing two aliphatic hydroxyl groups and one carboxyl group is used, it is preferable in terms of excellent photosensitivity of the photosensitive resin composition.

  The diisocyanate compound is not particularly limited as long as it has the above structure. For example, diphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4,3'- Or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2 ' -Or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3 '-Or 4,2'- or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethoxydiphenylmethane-2,4'-diisocyanate, diphenylmethane- 4,4'-diisocyanate, diphenyl Tan-3,3'-diisocyanate, diphenylmethane-3,4'-diisocyanate, diphenyl ether-4,4'-diisocyanate, benzophenone-4,4'-diisocyanate, diphenylsulfone-4,4'-diisocyanate, tolylene-2, 4-diisocyanate, tolylene-2,6-diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, naphthalene-2,6-diisocyanate, 4,4 '-[2,2-bis (4-phenoxyphenyl) propane Aromatic diisocyanate compounds such as diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate Hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, aliphatic diisocyanate compounds such as lysine diisocyanate, and these can be used alone or in combinations of two or more.

  In particular, when an alicyclic diisocyanate and an aliphatic diisocyanate compound are used, it is preferable in that the photosensitive resin composition is excellent in photosensitivity.

  In the synthesis method of the component (A1) of the present invention, the blending amount of the diol compound and the diisocyanate compound is such that the ratio of the number of hydroxyl groups to the number of isocyanate groups is isocyanate group / hydroxyl group = 0.5 or more and 2.0 or less. It is obtained by blending and reacting in a solvent-free or organic solvent.

  Moreover, when using 2 or more types of diol compounds, reaction with a diisocyanate compound may be performed after mixing 2 or more types of diol compounds, or each diol compound and diisocyanate compound may be made to react separately. Good. Moreover, after making a diol compound and a diisocyanate compound react, you may make the obtained terminal isocyanate compound react with another diol compound, and also make this react with a diisocyanate compound. The same applies when two or more types of diisocyanate compounds are used. In this way, the desired component (A1) can be produced.

  The reaction temperature between the diol compound and the diisocyanate compound is preferably 40 to 160 ° C, and more preferably 60 to 150 ° C. When the temperature is lower than 40 ° C., the reaction time becomes too long. The reaction time can be appropriately selected depending on the scale of the batch and the reaction conditions employed. If necessary, the reaction may be performed in the presence of a catalyst such as a tertiary amine, an alkali metal, an alkaline earth metal, a metal such as tin, zinc, titanium, cobalt, or a metalloid compound.

  The above reaction can be carried out in the absence of a solvent. However, in order to control the reaction, it is desirable to carry out the reaction in an organic solvent system. For example, examples of the organic solvent include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, N , N-dimethylformamide, formamide solvents such as N, N-diethylformamide, N, N-dimethylacetamide, acetamide solvents such as N, N-diethylacetamide, N-methyl-2-pyrrolidone, N-vinyl-2 Examples include pyrrolidone solvents such as -pyrrolidone, hexamethylphosphoramide, and γ-butyrolactone. Further, if necessary, these organic polar solvents can be used in combination with an aromatic hydrocarbon such as xylene or toluene.

  Furthermore, for example, methyl monoglyme (1,2-dimethoxyethane), methyldiglyme (bis (2-methoxyether) ether), methyltriglyme (1,2-bis (2-methoxyethoxy) ethane), methyltetraglyme (Bis [2- (2-methoxyethoxyethyl)] ether), ethyl monoglyme (1,2-diethoxyethane), ethyldiglyme (bis (2-ethoxyethyl) ether), butyldiglyme (bis (2 Symmetric glycol diethers such as -butoxyethyl) ether), methyl acetate, ethyl acetate, isopropyl acetate, n-propyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether Cetate (aka carbitol acetate, 2- (2-butoxyethoxy) ethyl acetate)), diethylene glycol monobutyl ether acetate, 3-methoxybutyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether Acetates such as acetate, propylene glycol diacetate, 1,3-butylene glycol diacetate, dipropylene glycol methyl ether, tripropylene glycol methyl ether, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, tripylene glycol n Propyl ether, propylene glycol phenyl ether, dipropylene glycol dimethyl ether, 1,3-dioxolane, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, a solvent may be used ethers such as ethyl ether also ethylene glycol. Of these, symmetrical glycol diethers are preferably used because side reactions are unlikely to occur.

  The amount of solvent used in the reaction is desirably such that the solute weight concentration in the reaction solution, that is, the solution concentration is 5% by weight or more and 90% by weight or less. The solute weight concentration in the reaction solution is more preferably 10 wt% or more and 80 wt% or less. When the solution concentration is 5% or less, the polymerization reaction is difficult to occur, the reaction rate is lowered, and a desired structural substance may not be obtained.

<(A2) Resin containing radically polymerizable group in molecule and containing urethane bond>
The resin containing a radically polymerizable group in the molecule (A2) of the present invention and containing a urethane bond contains a radically polymerizable group and a urethane bond in which a polymerization reaction proceeds by at least one radical polymerization initiator. The polymer having a weight average molecular weight of 1,000 or more and 100,000 or less in terms of polyethylene glycol.

  Controlling the weight average molecular weight within the above range is preferable because the alkali developability of the photosensitive resin composition, the flexibility of the resulting cured film, and the chemical resistance are excellent. When the weight average molecular weight is 1,000 or less, flexibility and chemical resistance may be lowered. When the weight average molecular weight is 100,000 or more, alkali developability is lowered, and the viscosity of the photosensitive resin composition is reduced. May be higher.

  The radical polymerizable group of the component (A2) of the present invention is preferably an unsaturated double bond. Furthermore, the unsaturated double bond is preferably a (meth) acryloyl group or a vinyl group. The radical polymerizable group content can be measured as an iodine value in the same manner as the component (A1). The iodine value of the component (A2) is preferably 10 to 200, more preferably 50 to 150. When the iodine value is less than 10, the photosensitivity of the photosensitive resin composition may be lowered. When the iodine value is more than 200, the crosslinking density becomes high due to too many photosensitive groups, and the flexibility of the obtained cured film is increased. It may worsen and warp may increase.

  The component (A2) of the present invention is not particularly limited as long as it is a urethane bond-containing resin containing a radical polymerizable group in the molecule. For example, in the case of a urethane (meth) acrylate resin or a urethane-modified epoxy (meth) acrylate resin The resulting cured film is preferable because it is excellent in bending resistance and has little warpage.

  The component (A2) of the present invention can be obtained by an arbitrary reaction. For example, the urethane (meth) acrylate resin is a diol compound represented by the general formula (1) and the general formula (3). In addition to the diisocyanate compound represented by general formula (5)

(In the formula, R ₃ represents an r + 1 valent organic group, R ₄ represents hydrogen or an alkyl group, and r represents an integer of 1 to 3)
And / or a compound containing at least one (meth) acryloyl group and / or the following general formula (6)

(Wherein X ₂ represents an s + 1 valent organic group, X ₃ represents hydrogen or an alkyl group, and s represents an integer of 1 to 3)
It is obtained by reacting a compound containing an isocyanate group represented by the formula (1) and at least one (meth) acryloyl group.

  The diol compound is not particularly limited as long as it has the above structure. For example, ethylene glycol, diethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, Polyoxyalkylene such as alkylene diol such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and a random copolymer of tetramethylene glycol and neopentyl glycol A ring-opening addition reaction of diols, polyester diols obtained by reacting polyhydric alcohols and polybasic acids, polycarbonate diols having a carbonate skeleton, γ-butyllactone, ε-caprolactone, δ-valerolactone, etc. Polycaprolactone diol, bisphenol A, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, hydrogenated bisphenol A, ethylene oxide adduct of hydrogenated bisphenol A, propylene oxide adduct of hydrogenated bisphenol A, etc. These can be used alone or in combination of two or more.

  In particular, when a long-chain diol such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyalkylene diol, polyester diol, polycarbonate diol, or polycaprolactone diol is used, curing obtained by curing the photosensitive resin composition It is preferable in that the elastic modulus of the film is lowered and the flexibility and low warpage are excellent.

  The diisocyanate compound is not particularly limited as long as it has the above structure. For example, diphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4,3'- Or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2 ' -Or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3 '-Or 4,2'- or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethoxydiphenylmethane-2,4'-diisocyanate, diphenylmethane- 4,4'-diisocyanate, diphenyl Tan-3,3'-diisocyanate, diphenylmethane-3,4'-diisocyanate, diphenyl ether-4,4'-diisocyanate, benzophenone-4,4'-diisocyanate, diphenylsulfone-4,4'-diisocyanate, tolylene-2, 4-diisocyanate, tolylene-2,6-diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, naphthalene-2,6-diisocyanate, 4,4 '-[2,2-bis (4-phenoxyphenyl) propane Aromatic diisocyanate compounds such as diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate Hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, aliphatic diisocyanate compounds such as lysine diisocyanate, and these can be used alone or in combinations of two or more.

  In particular, when an alicyclic diisocyanate and an aliphatic diisocyanate compound are used, it is preferable in that the photosensitive resin composition is excellent in photosensitivity.

  Although the compound containing the said hydroxyl group and at least 1 (meth) acryloyl group will not be specifically limited if it is the said structure, For example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2- Hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-hydroxy-1-acryloxy-3-methacryloxypropane, o-phenylphenol glycidyl ether (meth) acrylate, polyethylene glycol mono (meth) ) Acrylate, pentaerythritol tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, 1,4-cyclohexanedimethanol mono (meth) acrylate, 4-hydroxy Phenyl (meth) acrylate, 2- (4-hydroxyphenyl) ethyl (meth) acrylate, N-methylol acrylamide, 3,5-dimethyl-4-hydroxybenzyl acrylamide, etc. may be mentioned, and these may be used alone or in combination of two or more. Can be used in combination.

  The compound containing the isocyanate group and at least one (meth) acryloyl group is not particularly limited as long as it has the above structure. For example, 2- (meth) acryloyloxyethyl isocyanate, 1,1- (bisacryloyloxymethyl) ) Ethyl isocyanate, 2- (2-methacryloyloxyethyloxy) ethyl isocyanate and the like, and these can be used alone or in combination of two or more.

  The method for synthesizing the component (A2) of the present invention contains a diol compound, a diisocyanate compound, a compound containing a hydroxyl group and at least one (meth) acryloyl group, and / or an isocyanate group and at least one (meth) acryloyl group. It is obtained by blending the compound with a compound such that the ratio of the number of hydroxyl groups to the number of isocyanate groups is isocyanate group / hydroxyl group = 0.5 or more and 2.0 or less and reacting in a solvent-free or organic solvent. .

  Moreover, when using 2 or more types of diol compounds, reaction with a diisocyanate compound may be performed after mixing 2 or more types of diol compounds, or each diol compound and diisocyanate compound may be made to react separately. Good. Moreover, after reacting a diol compound and a diisocyanate compound, the obtained terminal isocyanate compound may be further reacted with a compound containing a hydroxyl group and at least one (meth) acryloyl group. When two or more types of diisocyanate compounds are used, the reaction with the diol compound may be performed after mixing two or more types of diisocyanate compounds, or each diisocyanate compound and the diol compound may be reacted separately. Good. Further, after reacting the diisocyanate compound and the diol compound, the obtained terminal hydroxyl compound may be further reacted with a compound containing isocyanate and at least one (meth) acryloyl group. In this way, the desired component (A2) can be produced.

  The reaction temperature between the diol compound and the diisocyanate compound is preferably 40 to 160 ° C, and more preferably 60 to 150 ° C. When the temperature is lower than 40 ° C., the reaction time becomes too long. The reaction time can be appropriately selected depending on the scale of the batch and the reaction conditions employed. If necessary, the reaction may be performed in the presence of a catalyst such as a tertiary amine, an alkali metal, an alkaline earth metal, a metal such as tin, zinc, titanium, cobalt, or a metalloid compound.

  The above reaction can be carried out in the absence of a solvent. However, in order to control the reaction, it is desirable to carry out the reaction in an organic solvent system. For example, examples of the organic solvent include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide, N , N-dimethylformamide, formamide solvents such as N, N-diethylformamide, N, N-dimethylacetamide, acetamide solvents such as N, N-diethylacetamide, N-methyl-2-pyrrolidone, N-vinyl-2 Examples include pyrrolidone solvents such as -pyrrolidone, hexamethylphosphoramide, and γ-butyrolactone. Further, if necessary, these organic polar solvents can be used in combination with an aromatic hydrocarbon such as xylene or toluene.

  Furthermore, for example, methyl monoglyme (1,2-dimethoxyethane), methyldiglyme (bis (2-methoxyether) ether), methyltriglyme (1,2-bis (2-methoxyethoxy) ethane), methyltetraglyme (Bis [2- (2-methoxyethoxyethyl)] ether), ethyl monoglyme (1,2-diethoxyethane), ethyldiglyme (bis (2-ethoxyethyl) ether), butyldiglyme (bis (2 Symmetric glycol diethers such as -butoxyethyl) ether), methyl acetate, ethyl acetate, isopropyl acetate, n-propyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether Cetate (aka carbitol acetate, 2- (2-butoxyethoxy) ethyl acetate)), diethylene glycol monobutyl ether acetate, 3-methoxybutyl acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether Acetates such as acetate, propylene glycol diacetate, 1,3-butylene glycol diacetate, dipropylene glycol methyl ether, tripropylene glycol methyl ether, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, tripylene glycol n Propyl ether, propylene glycol phenyl ether, dipropylene glycol dimethyl ether, 1,3-dioxolane, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, a solvent may be used ethers such as ethyl ether also ethylene glycol. Of these, symmetrical glycol diethers are preferably used because side reactions are unlikely to occur.

  The amount of solvent used in the reaction is desirably such that the solute weight concentration in the reaction solution, that is, the solution concentration is 5% by weight or more and 90% by weight or less. The solute weight concentration in the reaction solution is more preferably 10 wt% or more and 80 wt% or less. When the solution concentration is 5% or less, the polymerization reaction is difficult to occur, the reaction rate is lowered, and a desired structural substance may not be obtained.

  Examples of the urethane-modified epoxy (meth) acrylate resin include trade names KAYARAD UXE-3000 and UXE-3024 manufactured by Nippon Kayaku Co., Ltd.

  The component (A2) can be used alone or in combination of two or more.

  The content of the component (A2) of the present invention is preferably 10 to 200 parts by weight, more preferably 10 to 100 parts by weight of the component (A2) with respect to 100 parts by weight of the component (A1). This is preferable because the resolution of the fine pattern obtained from the composition, the flexibility of the resulting cured film, and the chemical resistance are excellent.

<(B) Crosslinked polymer particles>
The (B) crosslinked polymer particle of the present invention is a spherical polymer having a crosslinked structure in the molecule and an average particle diameter of 1 to 100 μm. When the average particle size is 1 μm or less, the viscosity and thixotropy of the photosensitive resin composition are increased, and appearance defects may occur due to foaming of the coating film during coating or insufficient leveling, and the average particle size is 100 μm. In the above case, the particles may be exposed to the opening when the fine pattern is formed, resulting in poor resolution. Here, the spherical shape may be a true spherical shape or an elliptical shape.

  The average particle size of the component (B) of the present invention is preferably 1 to 50 μm, more preferably 1 to 10 μm, so that the resolution of the fine pattern, the flexibility of the resulting cured film, and the chemical resistance are excellent. Therefore, it is preferable.

  The average particle diameter of the component (B) of the present invention can be measured, for example, as a volume-based median diameter (particle diameter with respect to an integrated distribution value of 50%) by the following method.

(Average particle size measurement)
Equipment used: LA-950V2 or equivalent manufactured by Horiba, Ltd. Measurement method: Laser diffraction / scattering method

  The content of the component (B) of the present invention is preferably 30 to 100 parts by weight, more preferably 40 to 80 parts by weight with respect to 100 parts by weight as a total of the components (A1) and (A2). As a result, it is possible to effectively form unevenness on the surface of the resulting cured film, and it is excellent in tack-free properties. Since filling and curing with the component (B) is obtained, the warpage of the cured film is reduced, and the stress relaxation effect and fracture toughness are improved. This improves the flexibility that can withstand repeated bending. When the amount of the component (B) is less than 30 parts by weight, it may be inferior in tack-free property or flexibility capable of withstanding repeated bending, and when it is more than 100 parts by weight, a flame retardant or photosensitive resin composition solution is applied. In some cases, the coatability of the coating deteriorates, and appearance defects may occur due to foaming of the coating film or insufficient leveling during coating.

  The component (B) of the present invention is not particularly limited. For example, as polymethyl methacrylate-based crosslinked polymer particles, product names Gantz Pearl GM-0600, GM-0600W, and crosslinked polymethacrylic acid manufactured by Gantz Kasei Co., Ltd. As methyl-based crosslinked polymer particles, product names Gantz Pearl GM-0105, GM-0205S, GM-0401S, GM-0407S, GM-0449S, GM-0630H, GM-0801S, GM-0807S, manufactured by Gantz Kasei Co., Ltd. GM-0849SGM-1001, GM-1001-S, GM-1007S, GM-1407S, GM-1505S-S, GM-2001, GM-2003S-S, GM-2007S, GM-2801, GM-4003, GM- 5003, GM-9005, GMX-0610, GM -0810, GMP-0800, GMDM-050M, GMDM-080M, GMDM-100M, GMDM-150M, product names manufactured by Sekisui Plastics Co., Ltd. Techpolymer MBX-5, MBX-8, MBX-12, crosslinked polymethacryl Examples of acid butyl-based crosslinked polymer particles include Gantz Pearl GB-05S, GB-08S, GB-10S, GB-15S, and Sakusui Chemicals Co., Ltd. , BM30X-8, the cross-linked acrylic cross-linked polymer particles are manufactured by Gantz Kasei Co., Ltd. product name Gantz Pearl GMP-0820, and the acrylic copolymer cross-linked polymer particles are manufactured by Gantz Kasei Co., Ltd. product name Gantz Pearl GBM-55COS. As crosslinked styrene-based crosslinked polymer particles, As product names GANTZPARL GS-0605, GS-1105 manufactured by Tsusei Corporation, product names Techpolymer SBX-6, SBX-8, and crosslinked polyacrylate ester-based crosslinked polymer particles manufactured by Sekisui Chemicals Co., Ltd. Product names manufactured by Sekisui Plastics Co., Ltd. Techpolymer ABX-8, AF10X-8, AFX-15, ARX-15, and nylon-based crosslinked polymer particles include product names Gantz Pearl GPA-550, manufactured by Gantz Kasei Co., Ltd. As the silicone-based crosslinked polymer particles, the product names Gantz Pearl SI-020, SI-030, SI-045 manufactured by Gantz Kasei Co., Ltd. As the crosslinked silicone-based crosslinked polymer particles, the product name Gantz Pearl SIG manufactured by Gantz Chemical Co., Ltd. -070, a crosslinked urethane-based crosslinked polymer particle is a product of Dainichi Seika Kogyo Co., Ltd. Product Name Dymic Beads UCN-8070CM Clear, UCN-8150CM Clear, UCN-5070D Clear, UCN-5150D Clear, Trade Names Art Pearl C-100 Transparent, C-200 Transparent, C-300 Transparent, C -300WA, C-400 transparent, C-400WA, C-600 transparent, C-800 transparent, C-800WA, P-400T, P-800T, U-600T, CF-600T, JB-400T, JB-800T, CE-400T, CE-800T etc. are mentioned, These can be used individually or in combination of 2 or more types.

  The component (B) of the present invention uses the crosslinked polymer particles containing a urethane bond in the molecule among the above-mentioned crosslinked polymer particles, in order to improve the flexibility that can withstand bending of the insulating film and withstand repeated bending. Is preferable.

<(C) Thermosetting resin>
The (C) thermosetting resin of the present invention is a compound containing at least one thermosetting organic group in the molecule.

  (C) component of this invention will not be specifically limited if it is the said structure, For example, an epoxy resin, an oxetane resin, a phenol resin, an isocyanate resin, a block isocyanate resin, a bismaleimide resin, a bisallyl nadiimide resin, a polyester resin (For example, unsaturated polyester resin), diallyl phthalate resin, silicon resin, vinyl ester resin, melamine resin, polybismaleimide triazine resin (BT resin), cyanate resin (for example, cyanate ester resin), urea resin, guanamine resin, sulfoamide Resins, aniline resins, polyurea resins, thiourethane resins, polyazomethine resins, episulfide resins, ene-thiol resins, benzoxazine resins, copolymer resins thereof, modified resins obtained by modifying these resins, or these Mixtures of resins with each other or other resins and the like.

  The component (C) of the present invention, among the above-mentioned thermosetting resins, can use a polyfunctional epoxy resin, in particular, can impart heat resistance to a cured film obtained by curing the photosensitive resin composition, This is preferable because adhesion to a conductor such as a metal foil or a circuit board can be imparted.

  The polyfunctional epoxy resin is a compound containing at least two epoxy groups in the molecule. For example, as the bisphenol A type epoxy resin, trade names jER828, jER1001, jER1002, and Japan Corporation made by Japan Epoxy Resin Co., Ltd. ADEKA brand name Adeka Resin EP-4100E, Adeka Resin EP-4300E, Nippon Kayaku Co., Ltd. trade names RE-310S, RE-410S, DIC Corporation trade names Epicron 840S, Epicron 850S, Epicron 1050, Epicron 7050 Toto Kasei Co., Ltd. trade names Epototo YD-115, Epototo YD-127, Epototo YD-128, Bisphenol F type epoxy resin, trade names jER806, jE made by Japan Epoxy Resin Co., Ltd. 807, trade names Adeka Resin EP-4901E, Adeka Resin EP-4930, Adeka Resin EP-4950, manufactured by Adeka Co., Ltd., trade names RE-303S, RE-304S, RE-403S, RE-404S, DIC manufactured by Nippon Kayaku Co., Ltd. Product names Epicron 830 and Epicron 835 manufactured by Co., Ltd. Product names Epototo YDF-170, Epototo YDF-175S, Epototo YDF-2001, and Bisphenol S type epoxy resin manufactured by Toto Kasei Co., Ltd. As Epiklon EXA-1514 and hydrogenated bisphenol A type epoxy resin, trade names jERYX8000, jERYX8034, jERYL7170, manufactured by Japan Epoxy Resin Co., Ltd., and Adeka Resin EP-4 manufactured by ADEKA Co., Ltd. 80E, DIC Corporation trade name Epicron EXA-7015, Toto Kasei Co., Ltd. trade name Epototo YD-3000, Epototo YD-4000D, biphenyl type epoxy resin, Japan Epoxy Resin Corporation trade name jERYX4000, jERYL6121H, jERYL6640, jERYL6667, Nippon Kayaku Co., Ltd. trade name NC-3000, NC-3000H, phenoxy type epoxy resin, Japan Epoxy Resin Co., Ltd. trade name jER1256, jER4250, jER4275, naphthalene type epoxy resin Are DIC Corporation's trade names Epicron HP-4032, Epicron HP-4700, Epicron HP-4200, Nippon Kayaku Co., Ltd. trade names NC-7000L, Phenoh As the lenovolac type epoxy resin, trade names jER152 and jER154 manufactured by Japan Epoxy Resin Co., Ltd., trade names EPPN-201-L manufactured by Nippon Kayaku Co., Ltd., trade names Epicron N-740 manufactured by DIC Corporation, and Epicron N- 770, product names Epototo YDPN-638 manufactured by Tohto Kasei Co., Ltd., and cresol novolak type epoxy resins include product names EOCN-1020, EOCN-102S, EOCN-103S, EOCN-104S, DIC shares manufactured by Nippon Kayaku Co., Ltd. Brand names EPIKRON N-660, Epicron N-670, Epicron N-680, Epicron N-695, and trisphenol methane type epoxy resins manufactured by the company include trade names EPPN-501H and EPPN-501HY manufactured by Nippon Kayaku Co., Ltd. EPPN-502 As a dicyclopentadiene type epoxy resin, trade name XD-1000 manufactured by Nippon Kayaku Co., Ltd., as trade name Epicron HP-7200 manufactured by DIC Corporation, and as an amine type epoxy resin, a product manufactured by Japan Epoxy Resin Co., Ltd. Names jER604, jER630, Toto Kasei Co., Ltd. trade names Epototo YH-434, Epototo YH-434L, Mitsubishi Gas Chemical Co., Ltd. trade names TETRAD-X, TERRAD-C, and flexible epoxy resins include Japan Epoxy Resin Trade names jER871, jER872, jERYL7175, jERYL7217, DIC Corporation's trade name Epicron EXA-4850, and urethane-modified epoxy resins include ADEKA Corporation's trade names Adeka Resin EPU-6, Adeka Resin Examples of PU-73, Adeka Resin EPU-78-11, and rubber-modified epoxy resins include Adeka Resin EPR-4023, Adeka Resin EPR-4026, Adeka Resin EPR-1309, and Adeka Resin EPR-1309. Examples of the product names Adeka Resin EP-49-10, Adeka Resin EP-49-20, and heterocyclic-containing epoxy resins include the product names TEPIC manufactured by Nissan Chemical Co., Ltd.

  Although it does not specifically limit as a hardening | curing agent of the said thermosetting resin in the photosensitive resin composition of this invention, For example, phenol resins, such as a phenol novolak resin, a cresol novolak resin, a naphthalene type phenol resin, an amino resin, and a urea resin , Melamine, dicyandiamide and the like, and these can be used alone or in combination of two or more.

  Further, the curing accelerator is not particularly limited, but for example, phosphine compounds such as triphenylphosphine; amine compounds such as tertiary amine, trimethanolamine, triethanolamine and tetraethanolamine; 1,8- Borate compounds such as diaza-bicyclo [5,4,0] -7-undecenium tetraphenylborate, imidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-un Imidazoles such as decylimidazole, 1-benzyl-2-methylimidazole, 2-heptadecylimidazole, 2-isopropylimidazole, 2,4-dimethylimidazole, 2-phenyl-4-methylimidazole; 2-methylimidazoline, 2- Ethyl imidazoline, 2 Imidazolines such as isopropylimidazoline, 2-phenylimidazoline, 2-undecylimidazoline, 2,4-dimethylimidazoline, 2-phenyl-4-methylimidazoline; 2,4-diamino-6- [2′-methylimidazolyl- ( 1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-undecylimidazolyl- (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2 ′ Examples include azine-based imidazoles such as -ethyl-4'-methylimidazolyl- (1 ')]-ethyl-s-triazine, and these can be used alone or in combination of two or more.

<(D) Photopolymerization initiator>
The (D) photopolymerization initiator of the present invention is a compound that is activated by energy such as UV and initiates / promotes a reaction of a radical polymerizable group.

  The component (D) of the present invention is not particularly limited as long as it has the above structure. For example, Michler's ketone, 4,4′-bis (diethylamino) benzophenone, 4,4 ′, 4 ″ -tris (dimethylamino) ) Triphenylmethane, 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-diimidazole, acetophenone, benzoin, 2-methylbenzoin, benzoinmethyl ester -Tell, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2-t-butylanthraquinone, 1,2-benzo-9,10-anthraquinone, methylanthraquinone, thioxanthone, 2,4-diethyl Thioxanthone, 2-isopropylthioxanthone, 1-hydroxycyclohexyl phenyl keto , Diacetylbenzyl, benzyldimethylketal, benzyldiethylketal, 2 (2′-furylethylidene) -4,6-bis (trichloromethyl) -S-triazine, 2 [2 ′ (5 ″ -methyl) Furyl) ethylidene] -4,6-bis (trichloromethyl) -S-triazine, 2 (p-methoxyphenyl) -4,6-bis (trichloromethyl) -S-triazine, 2,6-di (p-azidobenzal) ) -4-methylcyclohexanone, 4,4'-diazidochalcone, di (tetraalkylammonium) -4,4'-diazidostilbene-2,2'-disulfonate, 2,2-dimethoxy-1,2 -Diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propane 1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1- [4- (methylthio) phenyl]- 2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butane-1, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, Bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2-hydroxy-2-methyl-1-phenyl- Propane-1-ketone, bis (n5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pi 1-yl) -phenyl) titanium, 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)], iododium, (4-methylphenyl) [ 4- (2-methylpropyl) phenyl] -hexafluorophosphate (1-), ethyl-4-dimethylaminobenzoate, 2-ethylhexyl-4-dimethylaminobenzoate, ethanone, 1- [9-ethyl-6- ( 2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxyome) and the like, and these can be used alone or in combination of two or more.

<(E) Phosphorus flame retardant>
The (E) phosphorus flame retardant of the present invention is a compound that contains at least one phosphorus element in the molecule and has an effect of suppressing the combustion of organic matter.

  The component (E) of the present invention is not particularly limited as long as it has the above structure. For example, red phosphorus, condensed phosphate ester compounds, cyclic organic phosphorus compounds, phosphazene compounds, phosphorus-containing (meth) acrylate compounds , Phosphorus-containing epoxy compounds, phosphorus-containing polyol compounds, phosphorus-containing amine compounds, ammonium polyphosphate, melamine phosphate, phosphinate, and the like, and these can be used alone or in combination of two or more. .

  Among the phosphorus-based flame retardants, the component (E) of the present invention can impart excellent flame retardancy to a cured film obtained by curing a photosensitive resin composition, particularly using a phosphinate. In addition, since there is little bleed out of the flame retardant from the cured film, contact failure and process contamination can be suppressed, which is preferable.

  The phosphinic acid salt of the present invention is a compound represented by the following general formula (7).

(In the formula, R ₅ and R ₆ each independently represent a linear or branched alkyl group having 1 to 6 carbon atoms or an aryl group, and M represents Mg, Ca, Al, Sb, Sn, Ge, Ti. , Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na, and K represent metals selected from the group consisting of at least one of t.

  The phosphinic acid salt of the present invention is not particularly limited as long as it has the above structure. For example, aluminum trisdiethylphosphinate, aluminum trismethylethylphosphinate, aluminum trisdiphenylphosphinate, zinc bisdiethylphosphinate, bismethylethylphosphine Examples thereof include zinc oxide, zinc bisdiphenylphosphinate, titanyl bisdiethylphosphinate, titanyl bismethylethylphosphinate, titanyl bisdiphenylphosphinate, and the like. These can be used alone or in combination of two or more. It is preferable that the phosphinic acid salt of the present invention further contains an aluminum element from the viewpoint that high flame retardancy is obtained. It is preferable because of its property.

  The content of the phosphinic acid salt of the present invention is preferably 20 to 80 parts by weight, more preferably 25 to 75 parts by weight based on 100 parts by weight of the total of the components (A1) and (A2). Excellent cured flame resistance and electrical insulation reliability. When the amount of the component (E) is less than 20 parts by weight, the flame retardancy may be inferior. When the amount is more than 80 parts by weight, the coating property when applying the photosensitive resin composition solution is deteriorated, and the coating Appearance defects may occur due to foaming of the coating film or insufficient leveling.

<Other ingredients>
Various additives such as a radical polymerizable compound, a filler, an adhesion assistant, an antifoaming agent, a leveling agent, a colorant, and a polymerization inhibitor may be added to the photosensitive resin composition of the present invention as necessary. it can.

  The said radically polymerizable compound is a compound which contains the radically polymerizable group which a polymerization reaction advances with a radical polymerization initiator in a molecule | numerator. Among these, a resin having at least one unsaturated double bond in the molecule is preferable. Furthermore, the unsaturated double bond is preferably a (meth) acryloyl group or a vinyl group.

  Examples of the radical polymerizable compound include bisphenol F EO modified (n = 2 to 50) diacrylate, bisphenol A EO modified (n = 2 to 50) diacrylate, and bisphenol S EO modified (n = 2 to 50) diacrylate. Bisphenol F EO modified (n = 2-50) dimethacrylate, bisphenol A EO modified (n = 2-50) dimethacrylate, bisphenol S EO modified (n = 2-50) dimethacrylate, 1,6-hexanediol dimethacrylate Acrylate, neopentyl glycol diacrylate, ethylene glycol diacrylate, pentaerythritol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, tetramethyl Roll propane tetraacrylate, tetraethylene glycol diacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, ethylene glycol dimethacrylate, pentaerythritol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, dipentaerythritol Hexamethacrylate, tetramethylolpropane tetramethacrylate, tetraethylene glycol dimethacrylate, methoxydiethylene glycol methacrylate, methoxypolyethylene glycol methacrylate, β-methacryloyloxyethyl hydrogen phthalate, β-methacryloyloxyethyl hydrogen succinate, 3-chloro-2-hy Roxypropyl methacrylate, stearyl methacrylate, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, phenoxy polyethylene glycol acrylate, β-acryloyloxyethyl hydrogen succinate, lauryl acrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol Dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2-hydroxy-1,3-dimethacryloxypropane, 2,2-bis [4- (Methacryloxytoki Si) phenyl] propane, 2,2-bis [4- (methacryloxy-diethoxy) phenyl] propane, 2,2-bis [4- (methacryloxy-polyethoxy) phenyl] propane, polyethylene glycol diacrylate, tripropylene glycol diacrylate , Polypropylene glycol diacrylate, 2,2-bis [4- (acryloxydiethoxy) phenyl] propane, 2,2-bis [4- (acryloxypolyethoxy) phenyl] propane, 2-hydroxy-1-acryloxy-3- Methacryloxypropane, trimethylolpropane trimethacrylate, tetramethylolmethane triacrylate, tetramethylolmethane tetraacrylate, methoxydipropylene glycol methacrylate, methoxytriethylene Recall acrylate, nonylphenoxypolyethylene glycol acrylate, nonylphenoxypolypropylene glycol acrylate, 1-acryloyloxypropyl-2-phthalate, isostearyl acrylate, polyoxyethylene alkyl ether acrylate, nonylphenoxyethylene glycol acrylate, polypropylene glycol dimethacrylate, 1,4 -Butanediol dimethacrylate, 3-methyl-1,5-pentanediol dimethacrylate, 1,6-mexanediol dimethacrylate, 1,9-nonanediol methacrylate, 2,4-diethyl-1,5-pentanediol di Methacrylate, 1,4-cyclohexanedimethanol dimethacrylate, dipropylene glycol diacrylate , Tricyclodecane dimethanol diacrylate, 2,2-hydrogenated bis [4- (acryloxy polyethoxy) phenyl] propane, 2,2-bis [4- (acryloxy polypropoxy) phenyl] propane, 2,4- Diethyl-1,5-pentanediol diacrylate, ethoxylated tomethylolpropane triacrylate, propoxylated tomethylolpropane triacrylate, isocyanuric acid tri (ethane acrylate), pentathritol tetraacrylate, ethoxylated pentathritol tetraacrylate, propoxy Pentathritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol polyacrylate, triallyl isocyanurate, glycidyl methacrylate, glycidyl Ryl ether, 1,3,5-triacryloylhexahydro-s-triazine, triallyl 1,3,5-benzenecarboxylate, triallylamine, triallyl citrate, triallyl phosphate, arobarbital, diallylamine, diallyldimethylsilane, diallyl Disulfide, diallyl ether, zalyl sialate, diallyl isophthalate, diallyl terephthalate, 1,3-dialyloxy-2-propanol, diallyl sulfide diallyl maleate, 4,4′-isopropylidene diphenol dimethacrylate, 4,4′-isopropyl Examples thereof include redene diphenol diacrylate, and these can be used alone or in combination of two or more. In particular, when one containing 2 to 50 mol of EO (ethylene oxide) repeating units contained in one molecule of diacrylate or dimethacrylate is used, an aqueous development represented by an alkaline aqueous solution of the photosensitive resin composition is used. This is preferable because the solubility in the solution is improved and the development time is shortened.

  Examples of the filler include fine inorganic fillers such as silica, mica, talc, barium sulfate, wollastonite, and calcium carbonate.

  Examples of the antifoaming agent include acrylic compounds, vinyl compounds, butadiene compounds, and the like.

  Examples of the leveling agent include acrylic compounds and vinyl compounds.

  Examples of the colorant include phthalocyanine compounds, azo compounds, and carbon black.

  Examples of the adhesion assistant (also referred to as adhesion-imparting agent) include silane coupling agents, triazole compounds, tetrazole compounds, and triazine compounds.

  Examples of the polymerization inhibitor include hydroquinone and hydroquinone monomethyl ether.

  The photosensitive resin composition of the present invention is excellent in flame retardancy because it contains a phosphorus-based flame retardant, but another flame retardant may be added to obtain a higher flame retardant effect. As the flame retardant, for example, a halogen-containing compound, a metal hydroxide, a melamine compound, or the like can be added. The above various additives can be used alone or in combination of two or more.

<Method for mixing photosensitive resin composition>
The photosensitive resin composition of the present invention can be obtained by pulverizing and dispersing the above components and mixing them. The pulverizing / dispersing method is not particularly limited, and for example, it is performed using a general kneading apparatus such as a bead mill, a ball mill, or a three roll mill. The particle diameter of the particles contained in the photosensitive resin composition can be measured by a method using a grind gauge specified by JIS K 5600-2-5. Moreover, if a particle size distribution measuring apparatus is used, an average particle diameter, a particle diameter, and a particle size distribution can be measured.

(II) Method of using photosensitive resin composition Using the photosensitive resin composition of the present invention directly or after preparing a photosensitive resin composition solution, a cured film or a relief pattern is formed as follows. can do. First, the photosensitive resin composition or the photosensitive resin composition solution is applied to a substrate and dried to remove the organic solvent. The substrate can be applied by screen printing, curtain roll, river roll, spray coating, spin coating using a spinner, or the like. Drying of the coating film (preferably thickness: 5 to 100 μm, particularly 10 to 100 μm) is performed at 120 ° C. or less, preferably 40 to 100 ° C.

  Next, after drying, a negative photomask is placed on the dried coating film and irradiated with actinic rays such as ultraviolet rays, visible rays, and electron beams. Next, the relief pattern can be obtained by washing out the unexposed portion with a developer using various methods such as shower, paddle, immersion, or ultrasonic wave. Since the time until the pattern is exposed varies depending on the spraying pressure and flow rate of the developing device and the temperature of the etching solution, it is desirable to find the optimum device conditions as appropriate.

  As the developer, an alkaline aqueous solution is preferably used. This developer may contain a water-soluble organic solvent such as methanol, ethanol, n-propanol, isopropanol, or N-methyl-2-pyrrolidone. Examples of the alkaline compound that gives the alkaline aqueous solution include hydroxides, carbonates, hydrogen carbonates, amine compounds, and the like of alkali metals, alkaline earth metals, or ammonium ions, and specifically sodium hydroxide. , Potassium hydroxide, ammonium hydroxide, sodium carbonate, potassium carbonate, ammonium carbonate, sodium bicarbonate, potassium bicarbonate, ammonium bicarbonate, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetraisopropylammonium Hydroxide, N-methyldiethanolamine, N-ethyldiethanolamine, N, N-dimethylethanolamine, triethanolamine, triisopropanolamine, triiso Etc. can be mentioned Ropiruamin, aqueous solution with compounds of other long as it exhibits basicity can also be naturally used. The concentration of the alkaline compound that can be suitably used in the development step of the photosensitive resin composition of the present invention is preferably 0.01 to 20% by weight, particularly preferably 0.02 to 10% by weight. Further, the temperature of the developer depends on the composition of the photosensitive resin composition and the composition of the alkali developer, and is generally 0 ° C. or higher and 80 ° C. or lower, more generally 10 ° C. or higher and 60 ° C. or lower. Is preferably used.

  The relief pattern formed by the development process is rinsed to remove unnecessary residues. Examples of the rinsing liquid include water and acidic aqueous solutions.

  Next, heat treatment is performed on the obtained relief pattern. By carrying out heat treatment to react the reactive groups remaining in the molecular structure, a cured film having high heat resistance can be obtained. The thickness of the cured film is determined in consideration of the wiring thickness and the like, but is preferably about 2 to 50 μm. The final curing temperature at this time is desired to be able to be cured by heating at a low temperature for the purpose of preventing oxidation of the wiring and the like and not reducing the adhesion between the wiring and the substrate.

  The curing temperature at this time is preferably 100 ° C. or higher and 250 ° C. or lower, more preferably 120 ° C. or higher and 200 ° C. or lower, and particularly preferably 130 ° C. or higher and 180 ° C. or lower. If the final heating temperature is high, the wiring is oxidatively deteriorated, which is not desirable.

  The cured film formed from the photosensitive resin composition of the present invention is excellent in flexibility, flame retardancy, and electrical insulation reliability, and the warpage of the substrate after curing is small.

  In addition, for example, the insulating film obtained from the photosensitive resin composition preferably has a thickness of about 2 to 50 μm and a resolution of at least 10 μm after photocuring, particularly a resolution of about 10 to 1000 μm. For this reason, the insulating film obtained from the photosensitive resin composition is particularly suitable as an insulating material for a flexible substrate. Furthermore, it is used for various photo-curing wiring coating protective agents, photosensitive heat-resistant adhesives, electric wire / cable insulation coatings, and the like.

  In addition, this invention can provide the same insulating material even if it uses the resin film obtained by apply | coating the said photosensitive resin composition or the photosensitive resin composition solution to the base-material surface, and drying.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples.

(Synthesis Example 1)
<(A1) Resin containing substantially no radical polymerizable group in the molecule and containing a urethane bond and a carboxyl group>
Into a reaction vessel equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 30.00 g of methyltriglyme (= 1,2-bis (2-methoxyethoxy) ethane) was charged as a polymerization solvent, and this was mixed with norbornene diisocyanate 10 .31 g (0.050 mol) was charged and dissolved by heating to 80 ° C. with stirring under a nitrogen stream. To this solution was added 50.00 g (0.025 mol) of polycarbonate diol (manufactured by Asahi Kasei Corporation: trade name PCDL T5652, weight average molecular weight 2000) and 3.70 g (0.025) of 2,2-bis (hydroxymethyl) butanoic acid. Mol) in methyl triglyme (30.00 g) was added over 1 hour. This solution was reacted by heating and stirring at 80 ° C. for 5 hours. By performing the above reaction, a resin solution containing a urethane bond and a carboxyl group substantially free of radical polymerizable groups in the molecule was obtained. The obtained resin solution had a solid content concentration of 52%, a weight average molecular weight of 5,600, and a solid content acid value of 22 mgKOH / g. The solid content concentration, weight average molecular weight, and acid value were measured by the following methods.

<Concentration of solid content>
The measurement was performed according to JIS K 5601-1-2. The drying conditions were 150 ° C. × 1 hour.

<Weight average molecular weight>
Measurement was performed under the following conditions.
Equipment used: Tosoh HLC-8220GPC equivalent column: Tosoh TSK gel Super AWM-H (6.0 mm ID x 15 cm) x 2 guard columns: Tosoh TSK guard column Super AW-H
Eluent: 30 mM LiBr + 20 mM H3PO4 in DMF
Flow rate: 0.6 mL / min
Column temperature: 40 ° C
Detection conditions: RI: Polarity (+), response (0.5 sec)
Sample concentration: about 5 mg / mL
Standard product: PEG (polyethylene glycol)

<Acid value>
Measurement was performed according to JIS K 5601-2-1.

(Synthesis Example 2)
<(A2) Resin containing radically polymerizable group in molecule and containing urethane bond>
Into a reaction vessel equipped with a stirrer, a thermometer, and a nitrogen introduction tube, 30.00 g of methyltriglyme (= 1,2-bis (2-methoxyethoxy) ethane) was charged as a polymerization solvent, and this was mixed with norbornene diisocyanate 10 .31 g (0.050 mol) was charged and dissolved by heating to 80 ° C. with stirring under a nitrogen stream. To this solution, 50.00 g (0.025 mol) of polycarbonate diol (manufactured by Asahi Kasei Corporation: trade name PCDL T5652, weight average molecular weight 2000) and 6.51 g (0.050 mol) of 2-hydroxyethyl methacrylate were added to methyltriglyme. A solution dissolved in (30.00 g) was added over 1 hour. This solution was reacted by heating and stirring at 80 ° C. for 5 hours. By performing the above reaction, a resin solution containing a urethane bond and a methacryloyl group in the molecule was obtained. The resulting resin solution had a solid content concentration of 53% and a weight average molecular weight of 5,200. The solid content concentration and the weight average molecular weight were measured in the same manner as in Synthesis Example 1.

(Examples 1-6)
<Preparation of photosensitive resin composition>
(A1) component, (A2) component, (B) crosslinked polymer particles, (C) thermosetting resin, (D) photopolymerization initiator, (E) phosphorus flame retardant, other components, and an organic solvent are added. Thus, a photosensitive resin composition was prepared. Table 1 shows the blending amount of each constituent raw material in the resin solid content and the kind of the raw material. In addition, 1,2-bis (2-methoxyethoxy) ethane which is a solvent in the table is the total amount of the solvent including the solvent contained in the synthesized resin solution. The photosensitive resin composition was first mixed with a general stirring device with a stirring blade, and then passed twice with a three-roll mill to obtain a uniform solution. When the particle diameter was measured with a grind gauge, all were 10 μm or less. The following evaluation was carried out by completely defoaming the foam in the solution with a defoaming device.

<1> Product name of urethane-modified epoxy (meth) acrylate resin manufactured by Nippon Kayaku Co., Ltd. <2> Product name of cross-linked polymethyl methacrylate-based cross-linked polymer particles manufactured by Ganz Kasei Co., Ltd., average particle diameter: 2 μm
<3> Product name of cross-linked polybutyl methacrylate cross-linked polymer particles manufactured by Gantz Kasei Co., Ltd., average particle diameter of 5 μm
<4> manufactured by Dainichi Seika Kogyo Co., Ltd. Product name of crosslinked polymer particles containing urethane bonds in the molecule, average particle diameter of 7 μm
<5> Product name of polyfunctional epoxy resin (triglycidyl isocyanurate) manufactured by Nissan Chemical Co., Ltd. <6> Product name of photopolymerization initiator manufactured by BASF Japan Ltd. <7> Product name of phosphinic acid salt manufactured by Clariant Japan <8> Product name of EO-modified bisphenol A dimethacrylate manufactured by Hitachi Chemical Co., Ltd. <9> Product name of butadiene-based antifoaming agent manufactured by Kyoeisha Chemical Co., Ltd.

<Preparation of coating film on polyimide film>
The above photosensitive resin composition was cast and applied to an area of 100 mm × 100 mm on a 25 μm polyimide film (manufactured by Kaneka Co., Ltd .: trade name 25 NPI) using a Baker type applicator so that the final dry thickness was 20 μm. After drying at 80 ° C. for 20 minutes, exposure was performed by irradiating with an ultraviolet ray having an accumulated exposure amount of 300 mJ / cm ² . Subsequently, spray development was performed for 90 seconds at a discharge pressure of 1.0 kgf / mm ² using a solution obtained by heating a 1.0 wt% sodium carbonate aqueous solution to 30 ° C. After development, the film was sufficiently washed with pure water, and then cured by heating in an oven at 150 ° C. for 30 minutes to prepare a cured film of the photosensitive resin composition on the polyimide film.

<Evaluation of cured film>
The following items were evaluated. The evaluation results are shown in Table 2.

(I) Photosensitivity The surface of the cured film obtained by the same method as the above item <Preparation of coating film on polyimide film> was observed and determined. However, the exposure was performed by placing a negative photomask of line width / space width = 100 μm / 100 μm.
◯: A photosensitive pattern having a line width / space width = 100/100 μm can be drawn on the polyimide film surface without noticeable line thickness or development residue.
X: A line width / space width = 100/100 μm photosensitive pattern is not drawn on the polyimide film surface.

(Ii) Tack-free area Using a Baker type applicator, the photosensitive resin composition is an area of 100 mm × 100 mm so that the final dry thickness becomes 20 μm on a 25 μm polyimide film (manufactured by Kaneka Corporation: trade name 25 NPI). The coated film was dried at 80 ° C. for 20 minutes to produce a solvent-dried coating film. The method for evaluating the tack-free property of the coating film is to cut out the film with the coating film after drying the solvent into 50 mm x 30 mm strips, and the coating film surfaces overlap each other with the coating film on the inside. After applying a load of 300 g for 3 seconds, the load was removed and the state when the coating film surface was peeled off was observed.
○: There is no sticking between the coating films, and no sticking marks remain on the coating film.
(Triangle | delta): The coating films stick a little and the sticking trace remains in the coating film.
X: The coating films adhered completely and cannot be peeled off.

(Iii) Folding resistance of the photosensitive resin composition having a thickness of 20 μm on the surface of a polyimide film having a thickness of 25 μm (Apical 25NPI manufactured by Kaneka Corporation) in the same manner as the above item <Preparation of coating film on polyimide film>. A cured film laminated film was produced. The evaluation method of the bending resistance of the cured film laminated film is that the cured film laminated film is cut into 50 mm × 10 mm strips, bent at 180 ° at 25 mm with the cured film on the outside, and a load of 5 kg is applied to the bent portion for 3 seconds. After loading, the load was removed, and the apex of the bent portion was observed with a microscope. After microscopic observation, the bent portion was opened, and a 5 kg load was again applied for 3 seconds, and then the load was removed to completely open the cured film laminated film. The above operation was repeated, and the number of occurrences of cracks in the bent portion was defined as the number of bending times.
A: The cured film has no cracks after being bent five times.
Δ: The cured film has no cracks after being bent three times.
X: A crack occurs in the cured film at the first folding.

(Iv) Electrical insulation reliability Line width / space width on a flexible copper-clad laminate (thickness of electrolytic copper foil 12 μm, polyimide film is Apical 25 NPI manufactured by Kaneka Co., Ltd., copper foil is bonded with polyimide adhesive) = 100 μm / 100 μm comb-shaped pattern was prepared, immersed in a 10% by volume sulfuric acid aqueous solution for 1 minute, washed with pure water, and subjected to a copper foil surface treatment. Thereafter, a cured film of a photosensitive resin composition having a thickness of 20 μm was prepared on a comb pattern by the same method as the above item <Preparation of a coating film on a polyimide film>, and a test piece was prepared. A 100 V direct current was applied to both terminals of the test piece in an environmental test machine at 85 ° C. and 85% RH, and changes in the insulation resistance value and occurrence of migration were observed.
○: A resistance value of 10 8 or more in 1000 hours after the start of the test, and no occurrence of migration or dendrite.
X: Migration, dendrite, etc. occurred in 1000 hours after the start of the test.

(V) Solder heat resistance of a photosensitive resin composition having a thickness of 20 μm on the surface of a polyimide film having a thickness of 75 μm (Apical 75NPI manufactured by Kaneka Corporation) in the same manner as in the above item <Preparation of coating film on polyimide film>. A cured film laminated film was produced.
The obtained cured film laminated film was floated so that the surface coated with the cured film of the photosensitive resin composition was in contact with the solder bath completely dissolved at 260 ° C., and then pulled up 10 seconds later. The operation was performed three times, and the state of the film surface was observed.
○: There is no abnormality in the coating film.
X: Abnormality such as swelling or peeling occurs in the coating film.

(Vi) Warpage Cured film of photosensitive resin composition having a thickness of 20 μm on the surface of a polyimide film having a thickness of 25 μm (Apical 25 NPI manufactured by Kaneka Corporation) in the same manner as the above item <Preparation of coating film on polyimide film>. A laminated film was produced.
The obtained cured film laminated film was cut into an area of 50 mm × 50 mm and placed on a smooth table so that the coating film was on the upper surface, and the warp height of the film edge was measured. A schematic diagram of the measurement site is shown in FIG. The smaller the amount of warpage on the polyimide film surface, the smaller the stress on the surface of the printed wiring board and the lower the amount of warping of the printed wiring board. The warp amount is preferably 5 mm or less. In addition, when rounding cylindrically, it was set as x.

(Vii) Flame retardancy In accordance with the flammability test standard UL94VTM of plastic materials, the flammability test was performed as follows. In the same manner as the above item <Preparation of coating film on polyimide film>, a 25 μm-thick polyimide film (manufactured by Kaneka Corporation: trade name Apical 25 NPI) is coated with a 20 μm-thick photosensitive resin composition cured film laminated film. Was made. Cut out the sample prepared above into dimensions: 50 mm width x 200 mm length x 75 μm thickness (including the thickness of the polyimide film), put a marked line in the 125 mm part, round it into a cylinder with a diameter of about 13 mm, and above the marked line PI tape was affixed so that there was no gap in the overlapping part (75 mm) and the upper part, and 20 cylinders for flammability test were prepared. Of these, 10 were treated at (1) 23 ° C./50% relative humidity / 48 hours, and the remaining 10 were treated at (2) 70 ° C. for 168 hours and then cooled in a desiccator containing anhydrous calcium chloride for 4 hours or more. The upper part of these samples is clamped and fixed vertically, and a burner flame is brought close to the lower part of the sample for 3 seconds to ignite. After 3 seconds, move the burner flame away and measure how many seconds after the sample flame or burning disappears.
○: For each condition ((1), (2)), the flame and combustion stopped within 10 seconds on average (average of 10) after the flame of the burner was moved away from the sample, and self-extinguishment within 10 seconds at maximum However, it has not burned to the rating line.
×: Even one sample does not extinguish within 10 seconds, or the flame rises above the rating line and burns.

(Viii) Bleed-out The test piece after the electrical insulation reliability test was observed, and a minute bulge on the surface of the test piece, a bulge on the copper wiring, and a seepage of oily substances were observed.
○: No abnormalities such as swelling and bleeding on the surface of the test piece and the copper wiring in 1000 hours after the start of the test.
X: Abnormalities such as swelling and seepage appearing on the surface of the test piece and the copper wiring in 1000 hours after the start of the test.

(Comparative Example 1)
Instead of the cross-linked polymethyl methacrylate-based cross-linked polymer particles (manufactured by Ganz Kasei Co., Ltd., trade name Gantz Pearl GM-0105, average particle size 2 μm) used in Example 1, barium sulfate (Sakai Chemical Industry), which is an inorganic particle, was used. Physical properties were evaluated in the same manner as in Example 1 using a product name, Variace B-30, average particle size of 0.3 μm, manufactured by Co., Ltd. The results are listed in Table 2.

(Comparative Example 2)
After introducing air into a reaction vessel equipped with a stirrer, a thermometer, a cooling pipe and an air introduction pipe, polycarbonate diol (manufactured by Daicel Chemical Industries, trade name: Plaxel CD205PL, number average molecular weight: 500), 196.80 g (0.39 mol) ), 2,2-bis (hydroxymethyl) butanoic acid 58.30 (0.39 mol) g, diethylene glycol 37.60 g (0.35 mol), 1,4-cyclohexanedimethanol monoacrylate 148.10 g (0.75 mol) g, 0.55 g of p-methoxyphenol, 0.55 g of dibutyltin dilaurate, and 110.20 g of methyl ethyl ketone were charged, and the temperature was raised to 65 ° C. with uniform stirring under an air stream. 305.90 g (1.46 mol) of trimethylhexamethylene diisocyanate was charged into the dropping vessel and dropped into the reaction vessel over 3 hours with uniform stirring at 65 ° C. After completion of the dropping, the dropping container was washed with 76.50 g of methyl ethyl ketone, and the washed solution was directly put into the reaction container. Further, the mixture was kept warm for 2 hours with uniform stirring, then heated to 75 ° C. and stirred uniformly for 5 hours. Next, 9.30 g of methanol was added to the reaction vessel, and stirred uniformly at 60 ° C. for 30 minutes. Thereafter, 56.40 g of methyl ethyl ketone was added to obtain a transparent resin solution. By performing the above reaction, a resin solution containing a urethane bond and a methacryloyl group in the molecule was obtained. The resulting resin solution had a solid content concentration of 75% and a weight average molecular weight of 14,800. The solid content concentration and the weight average molecular weight were measured in the same manner as in Synthesis Example 1. 66.7 g (50 g as a solid content) of the obtained resin solution, 30 g of 2,2′-bis (4-methacryloxypentaethoxyphenyl) propane as a radical polymerizable compound, methacrylic acid, methyl methacrylate and acrylic as a binder resin Resin solution obtained by copolymerizing butyl acid in a weight ratio of 22: 71: 7 (weight average molecular weight is 80,000, solid content acid value is 143 mgKOH / g, methyl cellosolve / toluene = 6/4 (weight ratio 162.5 g (solid solution 65 g), benzophenone 3.5 g and N, N′-tetraethyl-4,4′-diamino as a photopolymerization initiator 0.1 g of benzophenone, an isocyanurate type hexamethylene diisocyanate-based isocyanate compound as a thermosetting resin 20 g of a 75% methyl ethyl ketone solution of a blocked isocyanate compound obtained by reacting methyl ethyl ketone oxime as a locking agent (15 g as a solid content), 40 g of a product name CR-747 manufactured by Daihachi Chemical Industry Co., Ltd. as a phosphorus flame retardant A photosensitive resin composition was prepared by mixing and stirring 85 g of acetone as an agent and dispersing the mixture with three rolls. The physical properties of this photosensitive resin composition were evaluated in the same manner as in Example 1. The results are listed in Table 2. In addition, (A1) component and (B) component are not contained in the said photosensitive resin composition.

(Comparative Example 3)
80.00 g of ethyl carbitol acetate was added to 100.00 g of cresol novolac type epoxy resin YDCN-703 (Epto equivalent 200, manufactured by Tohto Kasei Co., Ltd.), and heated and dissolved at 120 ° C. with stirring. After cooling to 60 ° C., 43.48 g (20.00 g as a solid content) of an emulsion of (meth) acrylic acid ester polymer fine particles (glass transition temperature—8 ° C., solid content: 46.0%) was added and stirred. The temperature was raised to 130 ° C. to completely remove water. Next, 36.90 g of acrylic acid, 0.14 g of chromic chloride hexahydrate and 0.11 g of methylhydroquinone were added and reacted at 110 ° C. for 3 hours. The acid value of the reaction product was 3.0 mgKOH / g, and the introduction of an acryloyl group was confirmed. Next, 45.60 g of tetrahydrophthalic anhydride, 29.00 g of ethyl carbitol acetate and 0.14 g of anhydrous lithium chloride are added and reacted at 100 ° C. for 3 hours to obtain 6.4 (meth) acrylic acid ester polymer fine particles. % And a mixed resin solution of ethyl carbitol acetate containing 58.6% of a photocurable resin having an acid value of 90 mgKOH / g. 90 g of the obtained resin solution (5.8 g of polymer fine particles as solid content, 52.7 g of photocurable resin), 15.0 g of pentaerythritol tetraacrylate as a polyfunctional monomer, 20.0 g of ethyl carbitol acetate as a diluent, light 8.0 g of product name Irgacure 907 manufactured by BASF Japan Ltd. as a polymerization initiator, 20.0 g of phenol novolac type epoxy resin as a thermosetting resin, 2.0 g of dicyandiamide as an epoxy curing agent, and 30.0 g of barium sulfate as a filler Then, 1.2 g of product name Floren AC300 manufactured by Kyoeisha Chemical Co., Ltd. as an antifoaming agent and 0.6 g of phthalocyanine green as a pigment were mixed and stirred and dispersed with a three roll to obtain a photosensitive resin composition. The physical properties of this photosensitive resin composition were evaluated in the same manner as in Example 1. The results are listed in Table 2. In addition, the (A1) component and the (A2) component are not included in the photosensitive resin composition.

DESCRIPTION OF SYMBOLS 1 Polyimide film which laminated the photosensitive resin composition 2 Warpage amount 3 Smooth stand

Claims (9)

A resin containing at least (A1) a radically polymerizable group in the molecule and containing a urethane bond and a carboxyl group,
(A2) a resin containing a radical polymerizable group in the molecule and containing a urethane bond,
(B) crosslinked polymer particles,
(C) thermosetting resin,
(D) contains a photopolymerization initiator ,
The resin containing a radical polymerizable group (A2) in the molecule and containing a urethane bond is a urethane (meth) acrylate resin,
The urethane (meth) acrylate resin is a diol compound represented by the following general formula (1)

(Wherein R ₁ represents a divalent organic group),
And a diisocyanate compound represented by the following general formula (3)

(Wherein X ₁ represents a divalent organic group)
The following general formula (5)

(In the formula, R ₃ represents an r + 1 valent organic group, R ₄ represents hydrogen or an alkyl group, r represents an integer of 1 to 3) and contains at least one (meth) acryloyl group. And / or the following general formula (6)

(Wherein X ₂ represents an s + 1 valent organic group, X ₃ represents hydrogen or an alkyl group, s represents an integer of 1 to 3) and at least one (meth) acryloyl group. It is a resin obtained by reacting a compound containing,
(C) above thermosetting resin, photosensitive resin composition which is a multifunctional epoxy resin:
Here, the (A1) molecule containing substantially no radical polymerizable group means that the value determined by measuring the radical polymerizable group in the molecule of (A1) as an iodine value is less than 5. It means that there is .   2. The photosensitive resin composition according to claim 1, wherein the (B) crosslinked polymer particles have an average particle diameter of 1 to 10 μm.   The blended amount of the (B) crosslinked polymer particles is (A1) a resin containing substantially no radical polymerizable group in the molecule and containing a urethane bond and a carboxyl group, and (A2) radical polymerizable in the molecule. 3. The photosensitive resin composition according to claim 1, wherein the content is 30 to 100 parts by weight with respect to 100 parts by weight in total of the resin containing a group and a urethane bond.   The photosensitive resin composition according to claim 1, wherein the (B) crosslinked polymer particle is a crosslinked polymer particle containing a urethane bond in the molecule.   The photosensitive resin composition according to any one of claims 1 to 4, further comprising (E) a phosphorus-based flame retardant.   The photosensitive resin composition according to claim 5, wherein the (E) phosphorus flame retardant is a phosphinate. The resin film obtained by apply | coating the photosensitive resin composition of any one of Claims 1-6 to the base-material surface at least, and drying. An insulating film obtained by curing the resin film according to claim 7 . A printed wiring board with an insulating film, wherein the insulating film according to claim 8 is coated on the printed wiring board.

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