JP2016136248A - Photosensitive composition and printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive composition capable of enhancing heat resistance to suppress discoloration and enhancing light resistance.SOLUTION: The photosensitive composition according to the present invention contains a polymerizable polymer having a carboxyl group, a photopolymerization initiator, an epoxy compound which is not liquid at 25°C, titanium oxide, and an inorganic filler different from titanium oxide. The photosensitive composition contains, as the epoxy compound which is not liquid at 25°C, a bisphenol A novolac type epoxy compound, a biphenyl type epoxy compound, or an epoxy compound having a triazine skeleton. The content of the titanium oxide is 5 wt.% or more.SELECTED DRAWING: Figure 1

Description

  The present invention is a photosensitive material suitably used for forming a solder resist film on a substrate, or forming a resist film that reflects light on a substrate on which an optical semiconductor element such as a light-emitting diode chip is mounted. Relates to the composition. Moreover, this invention relates to the printed wiring board using the said photosensitive composition.

  Conventionally, a printed wiring board in which a solder resist pattern, which is a patterned solder resist film, is formed on a substrate on which wiring is provided on the upper surface is often used.

  In various electronic device applications, an optical semiconductor element (for example, a light emitting diode (LED)) is mounted on the upper surface of a printed wiring board. A white solder resist film may be formed on the upper surface of the printed wiring board in order to use the light that has reached the upper surface side of the printed wiring board among the light emitted from the optical semiconductor element. In this case, not only light directly irradiated from the surface of the optical semiconductor element to the opposite side of the printed wiring board but also reflected light that reaches the upper surface side of the printed wiring board and is reflected by the white solder resist film is used. it can. Therefore, the utilization efficiency of light generated from the optical semiconductor element can be increased.

  As an example of a material for forming the white solder resist film, the following Patent Document 1 includes (A) a carboxyl group-containing resin, (B) a photopolymerization initiator, (C) an epoxy resin, and (D). An alkali development type photosensitive resin composition containing a (meth) acryl monomer is disclosed. This photosensitive resin composition contains (B) an acyl phosphine oxide photopolymerization initiator as a photopolymerization initiator, and (C) a bisphenol A novolac type epoxy resin as an epoxy resin.

Japanese Patent No. 5,507,023

  When obtaining a printed wiring board on which an optical semiconductor element is mounted, the resist film is exposed to a high temperature in an optical semiconductor element mounting process or the like. In the conventional composition, the resist film exposed to a high temperature may be discolored or the reflectance may be lowered.

  In the printed wiring board on which the optical semiconductor element is mounted, the resist film is irradiated with light emitted from the optical semiconductor element. The composition described in Patent Document 1 does not reflect light sufficiently when irradiated with light. Moreover, the composition of patent document 1 is not assumed actively for the light reflection use.

  Moreover, the conventional composition for forming a resist film may change color when irradiated with light.

  Thus, it is difficult for the conventional composition for forming a resist film to achieve both high heat resistance and high light resistance.

  An object of the present invention is to provide a photosensitive composition capable of enhancing heat resistance, suppressing discoloration, and enhancing light resistance. Moreover, the objective of this invention is providing the printed wiring board using the said photosensitive composition.

  With respect to the problem to be solved preferably by the present invention, the limited object of the present invention is to increase heat resistance and light resistance and to suppress a decrease in reflectance even when exposed to high temperature and high humidity conditions for a long time. It is providing the photosensitive composition which can be used, and the printed wiring board using the photosensitive composition.

  According to a wide aspect of the present invention, a polymerizable polymer having a carboxyl group, a photopolymerization initiator, an epoxy compound that is not liquid at 25 ° C., titanium oxide, and an inorganic filler different from titanium oxide, Photosensitivity containing a bisphenol A novolak type epoxy compound, a biphenyl type epoxy compound, or an epoxy compound having a triazine skeleton as the epoxy compound that is not liquid at 25 ° C., and the titanium oxide content is 5% by weight or more. A composition is provided.

  In a specific aspect of the photosensitive composition according to the present invention, the total content of the bisphenol A novolak type epoxy compound, the biphenyl type epoxy compound, and the epoxy compound having a triazine skeleton with respect to 100 parts by weight of the titanium oxide. 1 part by weight or more and 50 parts by weight or less.

  On the specific situation with the photosensitive composition which concerns on this invention, the said photosensitive composition contains a rutile type titanium oxide as the said titanium oxide.

  In a specific aspect of the photosensitive composition according to the present invention, the photosensitive composition contains talc or silica as the inorganic filler.

  The photosensitive composition according to the present invention is suitably used for forming a solder resist film.

  According to a wide aspect of the present invention, a printed wiring board body having a circuit on a surface thereof, and a solder resist film disposed on a surface of the printed wiring board body on which the circuit is provided, the solder resist film is provided. There is provided a printed wiring board which is a cured film of the photosensitive composition described above.

  On the specific situation with the printed wiring board concerning this invention, the said printed wiring board is provided with the optical semiconductor element arrange | positioned above the surface in which the said circuit of the said printed wiring board main body was provided.

  The photosensitive composition according to the present invention includes a polymerizable polymer having a carboxyl group, a photopolymerization initiator, an epoxy compound that is not liquid at 25 ° C., titanium oxide, and an inorganic filler different from titanium oxide. Since the epoxy compound that is not liquid at 25 ° C. contains a bisphenol A novolac type epoxy compound, a biphenyl type epoxy compound, or an epoxy compound having a triazine skeleton, and the content of the titanium oxide is 5% by weight or more, Heat resistance can be increased to suppress discoloration and light resistance can be increased.

FIG. 1 is a partially cutaway front sectional view schematically showing an example of an LED device having a resist film using a photosensitive composition according to an embodiment of the present invention.

  Details of the present invention will be described below.

(Photosensitive composition)
The photosensitive composition according to the present invention comprises a polymerizable polymer (A) having a carboxyl group, a photopolymerization initiator (B), an epoxy compound (C) that is not liquid at 25 ° C., and titanium oxide (D). And an inorganic filler (E) different from titanium oxide. In the photosensitive composition concerning this invention, the epoxy compound which has a bisphenol A novolak type epoxy compound, a biphenyl type epoxy compound, or a triazine skeleton is contained as an epoxy compound (C) which is not liquid at 25 degreeC. In the present invention, a specific epoxy compound is used together with titanium oxide (D). In the photosensitive composition concerning this invention, content of a titanium oxide is 5 weight% or more.

  In this invention, since the structure mentioned above is provided, heat resistance can be improved, discoloration can be suppressed, and light resistance can be improved. For example, when obtaining a printed wiring board on which an optical semiconductor element is mounted, the resist film is exposed to a high temperature in an optical semiconductor element mounting process or the like. By using the photosensitive composition according to the present invention, it is possible to suppress discoloration of a cured film such as a resist film exposed to a high temperature. That is, in the present invention, the heat resistance can be increased, specifically, the heat discoloration prevention property can be enhanced, and more specifically, the heat resistance yellowing prevention property can be enhanced.

  Furthermore, in the present invention, since the above-described configuration is provided, regarding the problem that is preferably solved by the present invention, a decrease in reflectance can be suppressed even when the cured product film is exposed to a high temperature.

  In the printed wiring board on which the optical semiconductor element is mounted, the resist film is irradiated with light emitted from the optical semiconductor element. By using the photosensitive composition according to the present invention, the reflectance of light by a cured film such as a resist film can be increased. In addition, the use of the photosensitive composition according to the present invention increases the light resistance of a cured film such as a resist film, so that a high light reflectance can be maintained even when light is irradiated for a long period of time.

  Furthermore, in the present invention, since the configuration described above is provided, stickiness of the surface of a cured film such as a resist film can be suppressed.

  Hereinafter, the detail of each component contained in the photosensitive composition concerning this invention is demonstrated.

(Polymerizable polymer (A))
The polymerizable polymer (A) has a carboxyl group. The polymerizable polymer (A) having a carboxyl group has polymerizability and can be polymerized. When the polymerizable polymer (A) has a carboxyl group, the developability of the photosensitive composition is improved. Examples of the polymerizable polymer (A) include an acrylic resin having a carboxyl group, an epoxy resin having a carboxyl group, and an olefin resin having a carboxyl group. The “resin” is not limited to a solid resin, and includes a liquid resin and an oligomer.

  The polymerizable polymer (A) is preferably the following carboxyl group-containing resins (a) to (e).

(A) carboxyl group-containing resin obtained by copolymerization of unsaturated carboxylic acid and compound having polymerizable unsaturated double bond (b) carboxyl group-containing (meth) acrylic copolymer resin (b1) and in one molecule A carboxyl group-containing resin obtained by reaction with a compound (b2) having an oxirane ring and an ethylenically polymerizable unsaturated double bond (c) one epoxy group and a polymerizable unsaturated double bond each in one molecule After reacting an unsaturated monocarboxylic acid with a copolymer of a compound having a polymerizable compound and a compound having a polymerizable unsaturated double bond, the secondary hydroxyl group of the resulting reaction product is saturated or unsaturated polybasic. Carboxyl group-containing resin obtained by reacting an acid anhydride (d) After reacting a hydroxyl group-containing polymer with a saturated or unsaturated polybasic acid anhydride, a polymer having a carboxyl group is formed. Hydroxyl and carboxyl group-containing resins obtained by reacting a compound with one epoxy group and a compound having a polymerizable unsaturated double bond in each molecule (e) an epoxy compound having an aromatic ring and a saturated polybasic acid Resin obtained by reacting anhydride or unsaturated polybasic acid anhydride, or epoxy compound having aromatic ring and carboxyl group-containing compound having at least one unsaturated double bond, and then saturated polybasic Carboxyl group-containing resin obtained by further reacting acid anhydride or unsaturated polybasic acid anhydride

  In 100% by weight of the photosensitive composition, the content of the polymerizable polymer (A) having a carboxyl group is preferably 3% by weight or more, more preferably 5% by weight or more, and preferably 50% by weight or less. Preferably it is 40 weight% or less. When the content of the polymerizable polymer (A) having a carboxyl group is not less than the above lower limit and not more than the above upper limit, the curability of the photosensitive composition is improved.

(Photopolymerization initiator (B))
Since the said photosensitive composition contains a photoinitiator (B), a photosensitive composition can be hardened by irradiation of light. The photopolymerization initiator (B) is not particularly limited. As for a photoinitiator (B), only 1 type may be used and 2 or more types may be used together.

  Examples of the photopolymerization initiator (B) include acylphosphine oxide, halomethylated triazine, halomethylated oxadiazole, imidazole, benzoin, benzoin alkyl ether, anthraquinone, benzanthrone, benzophenone, acetophenone, thioxanthone, and benzoic acid ester. , Acridine, phenazine, titanocene, α-aminoalkylphenone, oxime, and derivatives thereof. As for the said photoinitiator (B), only 1 type may be used and 2 or more types may be used together.

  From the viewpoint of further increasing the heat resistance and light resistance of the cured film and further suppressing the stickiness of the surface of the cured film, an acyl phosphine oxide photopolymerization initiator is preferred.

  The content of the photopolymerization initiator (B) is preferably 0.1 parts by weight or more, more preferably 1 part by weight or more, preferably 100 parts by weight of the polymerizable polymer (A) having a carboxyl group. 30 parts by weight or less, more preferably 15 parts by weight or less. When the content of the photopolymerization initiator (B) is not less than the above lower limit and not more than the above upper limit, the photosensitivity of the photosensitive composition is effectively increased.

(Epoxy compound that is not liquid at 25 ° C (C))
Examples of the epoxy compound include heterocyclic epoxy compounds such as bisphenol S type epoxy compound, diglycidyl phthalate compound, triglycidyl isocyanurate, bixylenol type epoxy compound, biphenol type epoxy compound, tetraglycidyl xylenoylethane compound, bisphenol. A type epoxy compound, hydrogenated bisphenol A type epoxy compound, bisphenol F type compound, brominated bisphenol A type epoxy compound, phenol novolac type epoxy compound, cresol novolak type epoxy compound, alicyclic epoxy compound, bisphenol A novolak type epoxy compound , Chelate-type epoxy compounds, glyoxal-type epoxy compounds, amino group-containing epoxy compounds, rubber-modified epoxy compounds, dicyclopentadi Nfenorikku type epoxy compounds, silicone-modified epoxy compounds and ε- caprolactone-modified epoxy compounds.

  In the present invention, an epoxy compound (C) that is not liquid at 25 ° C. and an epoxy compound (C) that is not liquid at 25 ° C. are bisphenol A novolak type epoxy compounds, biphenyl type epoxy compounds, or an epoxy having a triazine skeleton. Use compounds. By using this specific epoxy compound, heat resistance and light resistance can be increased, and surface stickiness can be suppressed.

  The epoxy compound (C) that is not liquid at 25 ° C. reacts with the carboxyl group of the polymerizable polymer (A) having a carboxyl group and acts to cure the photosensitive composition. As for the epoxy compound (C) which is not liquid at 25 degreeC, only 1 type may be used and 2 or more types may be used together.

  The photosensitive composition contains one or more of bisphenol A novolak type epoxy compounds, biphenyl type epoxy compounds, and epoxy compounds having a triazine skeleton. The photosensitive composition may contain a bisphenol A novolak type epoxy compound, may contain a biphenyl type epoxy compound, or may contain an epoxy compound having a triazine skeleton. The photosensitive composition may contain a bisphenol A novolac type epoxy compound. The photosensitive composition may contain a biphenyl type epoxy compound or an epoxy compound having a triazine skeleton.

  The content of the epoxy compound (C) that is not liquid at 25 ° C. is preferably 0.1 parts by weight or more, more preferably 1 part by weight with respect to 100 parts by weight of the polymerizable polymer (A) having a carboxyl group. The amount is preferably 50 parts by weight or less, more preferably 30 parts by weight or less. When the content of the epoxy compound (C) that is not liquid at 25 ° C. is not less than the above lower limit and not more than the above upper limit, the heat resistance, light resistance and electrical insulation of the cured film are further enhanced, and the surface is not sticky. It is further suppressed.

  The total content of the bisphenol A novolac type epoxy compound, the biphenyl type epoxy compound, and the epoxy compound having a triazine skeleton is preferably 0.1% by weight with respect to 100 parts by weight of the polymerizable polymer (A) having the carboxyl group. Part or more, more preferably 1 part by weight or more, preferably 50 parts by weight or less, more preferably 30 parts by weight or less. When the total content of the bisphenol A novolac type epoxy compound, the biphenyl type epoxy compound, and the epoxy compound having a triazine skeleton is not less than the above lower limit and not more than the above upper limit, the heat resistance, light resistance, and electrical insulation of the cured product film The property is further enhanced, and the stickiness of the surface is further suppressed.

  The content of the bisphenol A novolak epoxy compound is preferably 0.1 parts by weight or more, more preferably 1 part by weight or more, preferably 100 parts by weight of the polymerizable polymer (A) having a carboxyl group. 50 parts by weight or less, more preferably 30 parts by weight or less. The total content of the biphenyl type epoxy compound and the epoxy compound having a triazine skeleton is preferably 0.1 parts by weight or more, more preferably 1 with respect to 100 parts by weight of the polymerizable polymer (A) having the carboxyl group. Part by weight or more, preferably 50 parts by weight or less, more preferably 30 parts by weight or less.

(Titanium oxide (D))
Since the said photosensitive composition contains titanium oxide (D), hardened | cured material films, such as a resist film with a high reflectance, can be formed. Further, by using titanium oxide (D), a cured film such as a resist film having a high reflectance can be formed as compared with the case of using only an inorganic filler other than titanium oxide (D). The titanium oxide (D) contained in the said photosensitive composition is not specifically limited. As for titanium oxide (D), only 1 type may be used and 2 or more types may be used together.

  The titanium oxide (D) is preferably rutile titanium oxide or anatase titanium oxide. By using rutile type titanium oxide, a more excellent cured film can be obtained by heat-resistant yellowing. The anatase type titanium oxide has a lower hardness than the rutile type titanium oxide. For this reason, the use of anatase-type titanium oxide increases the processability of the cured product film.

  It is preferable that the said titanium oxide (D) contains the rutile type titanium oxide surface-treated with the silicon oxide or the silicone compound. In 100% by weight of the titanium oxide (D), the content of the rutile titanium oxide surface-treated with the silicon oxide or the silicone compound is preferably 10% by weight or more, more preferably 30% by weight or more, preferably 100% by weight. % (Total amount) or less. By using the rutile type titanium oxide surface-treated with the silicon oxide or the silicone compound, the heat-resistant yellowing of the cured film is further increased.

  Examples of the rutile-type titanium oxide surface-treated with a silicon oxide or a silicone compound include, for example, a product number: CR-90 manufactured by Ishihara Sangyo Co., Ltd., which is a rutile chlorine-based titanium oxide, and a product manufactured by Ishihara Sangyo Co., Ltd., which is a rutile sulfate titanium oxide Product number: R-550 etc. are mentioned.

  In order to increase the reflectance of light, the content of titanium oxide (D) is 5% by weight or more in 100% by weight of the photosensitive composition. In the present invention, even if the content of titanium oxide (D) is 5% by weight or more, by adopting the above composition, the heat resistance and light resistance of the cured film are increased, and the surface of the cured film is improved. Stickiness is suppressed.

  In 100% by weight of the photosensitive composition, the content of titanium oxide (D) and the content of rutile type titanium oxide are each preferably 10% by weight or more, more preferably 20% by weight or more, preferably 80% by weight. Below, more preferably 75% by weight or less, still more preferably 70% by weight or less. When the content of titanium oxide (D) is not less than the above lower limit and not more than the above upper limit, when the cured product film is exposed to high temperature, it becomes more difficult to discolor. Furthermore, a photosensitive composition having a viscosity suitable for coating can be easily prepared.

  The content of the epoxy compound (C) that is not liquid at 25 ° C. with respect to 100 parts by weight of the titanium oxide (D) is preferably 1 part by weight or more, more preferably 5 parts by weight or more, preferably 50 parts by weight or less. More preferably, it is 30 parts by weight or less, and still more preferably 15 parts by weight or less. The total content of the bisphenol A novolak type epoxy compound, the biphenyl type epoxy compound, and the epoxy compound having a triazine skeleton is preferably 1 part by weight or more, more preferably 5 parts by weight with respect to 100 parts by weight of the titanium oxide (D). Part or more, preferably 50 parts by weight or less, more preferably 30 parts by weight or less, still more preferably 15 parts by weight or less. When the content of the epoxy compound (C) that is not liquid at 25 ° C. and the total content of the bisphenol A novolak type epoxy compound, the biphenyl type epoxy compound, and the epoxy compound having a triazine skeleton are not less than the above lower limit and not more than the above upper limit. Further, the heat resistance and light resistance of the cured product film are further increased, and the stickiness of the surface of the cured product film is further suppressed.

(Inorganic filler different from titanium oxide (E))
The inorganic filler (E) is an inorganic filler different from titanium oxide. As for the said inorganic filler (E), only 1 type may be used and 2 or more types may be used together.

  Specific examples of the inorganic filler (E) include silica, alumina, mica, beryllia, potassium titanate, barium titanate, strontium titanate, calcium titanate, zirconium oxide, antimony oxide, aluminum borate, aluminum hydroxide, Magnesium oxide, calcium carbonate, magnesium carbonate, aluminum carbonate, calcium silicate, aluminum silicate, magnesium silicate, calcium phosphate, calcium sulfate, barium sulfate, silicon nitride, boron nitride, calcined clay, talc, silicon carbide, cross-linked Examples include acrylic resin particles and silicone particles. As for the said inorganic filler (E), only 1 type may be used and 2 or more types may be used together.

  From the viewpoint of further increasing the heat resistance and light resistance of the cured film and further suppressing the stickiness of the surface of the cured film, the photosensitive composition preferably contains talc or silica, and contains silica. It is more preferable. The photosensitive composition may contain talc.

  In 100% by weight of the photosensitive composition, the content of the inorganic filler (E) and the total content of talc and silica are each preferably 0.1% by weight or more, more preferably 1% by weight or more, More preferably, it is 3% by weight or more, preferably 50% by weight or less, more preferably 30% by weight or less, and still more preferably 10% by weight or less. When the content of the inorganic filler (E) and the total content of talc and silica are not less than the above lower limit and not more than the above upper limit, the heat resistance and light resistance of the cured film are further increased, and the surface is sticky. Is further suppressed.

  In 100% by weight of the photosensitive composition, the total content of the titanium oxide (D) and the inorganic filler (E) is preferably 5% by weight or more, more preferably 10% by weight or more, and still more preferably. It is 20% by weight or more, preferably 80% by weight or less, more preferably 60% by weight or less, and still more preferably 40% by weight or less. When the total content of the titanium oxide (D) and the inorganic filler (E) is not less than the above lower limit and not more than the above upper limit, the heat resistance and light resistance of the cured film are further enhanced, and the surface is not sticky. It is further suppressed.

  In the photosensitive composition, the weight ratio of the content of the titanium oxide (D) and the inorganic filler (E) (content of titanium oxide (D): content of inorganic filler (E) is preferably 0. 1: 99.9-99.9: 0.1, more preferably 1: 99-99: 1, and even more preferably 1: 9-9: 1.

(Other ingredients)
In order to further improve the curability, the photosensitive composition according to the present invention preferably contains a polymerizable monomer as a component different from the polymerizable polymer (A) having a carboxyl group. The photosensitive composition preferably contains both a polymerizable polymer (A) having a carboxyl group and a polymerizable monomer. The polymerizable monomer is polymerizable and can be polymerized. The polymerizable monomer is not particularly limited. As for the said polymerizable monomer, only 1 type may be used and 2 or more types may be used together.

  The polymerizable monomer is preferably a polymerizable unsaturated group-containing monomer. Examples of the polymerizable unsaturated group in the polymerizable monomer include functional groups having a polymerizable unsaturated double bond such as a (meth) acryloyl group and a vinyl ether group. A (meth) acryloyl group is preferred because the crosslink density of the cured product film can be increased.

  The polymerizable unsaturated group-containing monomer is preferably a compound having a (meth) acryloyl group. Examples of the compound having the (meth) acryloyl group include a di (meth) acrylate modified product of glycol such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol or propylene glycol, polyhydric alcohol, and ethylene oxide adduct of polyhydric alcohol. Or a polyhydric (meth) acrylate modified product of a propylene oxide adduct of a polyhydric alcohol, a (meth) acrylate modified product of phenol, an ethylene oxide adduct of phenol or a propylene oxide adduct of phenol, glycerin diglycidyl ether or (Meth) acrylate modified products of glycidyl ether such as trimethylolpropane triglycidyl ether and melamine (meth) acrylate are exemplified.

  Examples of the polyhydric alcohol include hexanediol, trimethylolpropane, pentaerythritol, dipentaerythritol, and tris-hydroxyethyl isocyanurate. Examples of the (meth) acrylate of phenol include phenoxy (meth) acrylate and di (meth) acrylate modified products of bisphenol A.

  “(Meth) acryloyl” means acryloyl and methacryloyl. “(Meth) acryl” means acrylic and methacrylic. “(Meth) acrylate” means acrylate and methacrylate.

  When the polymerizable monomer is contained, the content of the polymerizable monomer is 100% by weight in total of the polymerizable monomer and the polymerizable polymer (A) having a carboxyl group. Preferably it is 5 weight% or more, Preferably it is 50 weight% or less. When the content of the polymerizable monomer is not less than the above lower limit and not more than the above upper limit, the photosensitive composition is sufficiently cured. Furthermore, the crosslink density of the cured product film becomes appropriate, sufficient resolution is obtained, and the cured product film is hardly yellowed.

  In order to reduce the possibility that the cured film will turn yellow when exposed to high temperatures, the photosensitive composition preferably contains an antioxidant. The antioxidant preferably has a Lewis basic site. From the viewpoint of further suppressing the yellowing of the cured film, the antioxidant is preferably a phenolic antioxidant, a phosphorus antioxidant, and an amine antioxidant. From the viewpoint of further suppressing the yellowing of the cured film, the antioxidant is preferably a phenolic antioxidant. That is, the photosensitive composition preferably contains a phenolic antioxidant.

  Examples of commercially available phenolic antioxidants include IRGANOX 1010, IRGANOX 1035, IRGANOX 1076, IRGANOX 1135, IRGANOX 245, IRGANOX 259, and IRGANOX 295 (all of which are manufactured by Ciba Japan), ADK STAB AO-30, ADK STAB AO-40, ADK STAB AO-50, ADK STAB AO-60, ADK STAB AO-70, ADK STAB AO-80, ADK STAB AO-90, and ADK STAB AO-330 (all of which are manufactured by ADEKA), Sumilizer GA-80, Sumilizer MDP-S, Sumilizer BBM-S, Sumilizer GM, Sumilizer GS (F), and Sumilizer GP (all of which are manufactured by Sumitomo Chemical Co., Ltd.), HOSTANOX O10, HOSTANOX O16, HOSTANOX O14, and HOSTANOX O3 (all of which are manufactured by Clariant), Antage BHT, Antage W-300, Antage W-400 and Antage W500 (all are manufactured by Kawaguchi Chemical Industry Co., Ltd.), SEENOX 224M, and SENOX 326M (all are manufactured by Sipro Kasei Co., Ltd.).

  Examples of the phosphorus antioxidant include cyclohexylphosphine and triphenylphosphine. Commercially available products of the above phosphorus antioxidants include Adeastab PEP-4C, Adeastab PEP-8, Adeastab PEP-24G, Adeastab PEP-36, Adeastab HP-10, Adeastab 2112, Adeastab 260, Adeastab 522A, Adeastab 1178, Adeastab 1500, Adeastab C, Adeastab 135A, Adeastab 3010, and Adeastab TPP (all of which are manufactured by ADEKA), Sandstub P-EPQ, and Hostanox PAR24 (all of which are manufactured by Clariant), and JP-312L, JP -318-0, JPM-308, JPM-313, JPP-613M, JPP-31, JPP-2000PT, and JPH-3800 (all of which are Johoku Manabu Kogyo Co., Ltd.), and the like.

  Examples of the amine antioxidant include triethylamine, dicyandiamide, melamine, ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4-diamino-6-tolyl-S-triazine, 2,4- And diamino-6-xylyl-S-triazine and quaternary ammonium salt derivatives.

  The content of the antioxidant is preferably 0.1 parts by weight or more, more preferably 5 parts by weight or more, and preferably 30 parts by weight or less with respect to 100 parts by weight of the polymerizable polymer (A) having a carboxyl group. More preferably, it is 15 parts by weight or less. When the content of the antioxidant is not less than the above lower limit and not more than the upper limit, the heat-resistant yellowing is further increased.

  The photosensitive composition includes a colorant, an antifoaming agent, a curing agent, a curing accelerator, a mold release agent, a surface treatment agent, a flame retardant, a viscosity modifier, a dispersant, a dispersion aid, a surface modifier, and a plasticizer. , An antibacterial agent, an antifungal agent, a leveling agent, a stabilizer, a coupling agent, an anti-sagging agent or a phosphor may be included.

(Other details of photosensitive composition and printed wiring board)
The said photosensitive composition can be prepared by, for example, stirring and mixing each compounding component and then uniformly mixing with three rolls.

Examples of the light source used for curing the photosensitive composition include an irradiation device that emits active energy rays such as ultraviolet rays or visible rays. Examples of the light source include an ultrahigh pressure mercury lamp, a deep UV lamp, a high pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, and an excimer laser. These light sources are appropriately selected according to the photosensitive wavelength of the constituent components of the photosensitive composition. The irradiation energy of light is appropriately selected depending on a desired film thickness or a constituent of the photosensitive composition. The irradiation energy of light is generally in the range of 10 to 3000 mJ / cm ² .

  The photosensitive composition is used for forming a resist film, more preferably used for forming a resist film of an LED device, and more preferably used for forming a solder resist film. The photosensitive composition is preferably a resist composition, and is preferably a solder resist composition.

  The printed wiring board according to the present invention includes a printed wiring board body having a circuit on the surface, and a resist film disposed on the surface of the printed wiring board body on which the circuit is provided. The resist film is a cured product film of the photosensitive composition according to the present invention, and is formed of the photosensitive composition according to the present invention. The resist film is preferably a solder resist film. The printed wiring board preferably includes an optical semiconductor element disposed above a surface of the printed wiring board main body on which a circuit is provided.

  In FIG. 1, an example of the LED device which has a soldering resist film formed using the photosensitive composition which concerns on one Embodiment of this invention is typically shown with a partial notch front sectional drawing.

  In the LED device 1 shown in FIG. 1, a resist film 3 formed of a photosensitive composition is disposed on a surface 2 a (upper surface) of a substrate 2. A resist film 3 is laminated on the surface 2 a of the substrate 2. The resist film 3 is a pattern film. Therefore, the resist film 3 is not formed in a partial region of the surface 2 a of the substrate 2. Electrodes 4a and 4b are provided on the surface 2a of the substrate 2 where the resist film 3 is not formed. The substrate 2 is preferably a printed wiring board body. A circuit is preferably formed on the surface 2 a (upper surface) of the substrate 2.

  On the surface 2 a of the substrate 2, that is, above the surface 2 a of the substrate 2, LED chips 7 that are optical semiconductor elements are arranged. On the surface 3a (surface) of the resist film 3, the LED chip 7 is laminated. An LED chip 7 is disposed on the surface 2 a of the substrate 2 via the resist film 3. Terminals 8 a and 8 b are provided on the outer peripheral edge of the lower surface 7 a of the LED chip 7. The terminals 8a and 8b are electrically connected to the electrodes 4a and 4b by the solder 9a and 9b. By this electrical connection, power can be supplied to the LED chip 7.

  Hereinafter, the present invention will be clarified by giving specific examples and comparative examples of the present invention. The present invention is not limited to the following examples.

  In Examples and Comparative Examples, the following materials 1) to 12) were used.

  1) Acrylic polymer 1 (polymerizable polymer having a carboxyl group, acrylic polymer 1 obtained in Synthesis Example 1 below)

(Synthesis Example 1)
A flask equipped with a thermometer, a stirrer, a dropping funnel and a reflux condenser is charged with ethyl carbitol acetate as a solvent and azobisisobutyronitrile as a catalyst, heated to 80 ° C. in a nitrogen atmosphere, and methacrylic. A monomer in which acid and methyl methacrylate were mixed at a molar ratio of 30:70 was added dropwise over 2 hours. After dropping, the mixture was stirred for 1 hour, and the temperature was raised to 120 ° C. Then it was cooled. Glycidyl acrylate was added in such an amount that the molar ratio of the total amount of all the monomer units of the obtained resin was 10 and then heated at 100 ° C. for 30 hours using tetrabutylammonium bromide as a catalyst. The group was subjected to an addition reaction. After cooling, it was taken out from the flask to obtain a solution containing 50 wt% (nonvolatile content) of a carboxyl group-containing resin having a solid content acid value of 60 mg KOH / g, a weight average molecular weight of 15000, and a double bond equivalent of 1000. Hereinafter, this solution is referred to as acrylic polymer 1.

  2) DPHA (acrylic monomer, dipentaerythritol hexaacrylate, manufactured by Daicel Ornex)

  3) TPO (photopolymerization initiator which is a photo radical generator, manufactured by BASF Japan)

  4) 157S (bisphenol A novolac type epoxy resin, manufactured by Mitsubishi Chemical Corporation, solid at 25 ° C.)

  5) YX-4000 (biphenyl type epoxy resin, manufactured by Mitsubishi Chemical Corporation, solid at 25 ° C.)

  6) TEPIC (epoxy resin having a triazine skeleton, manufactured by Nissan Chemical Industries, solid at 25 ° C.)

  7) 828 (bisphenol A type epoxy resin, manufactured by Mitsubishi Chemical Corporation, liquid at 25 ° C)

  8) CR-50 (titanium oxide, manufactured by Ishihara Sangyo Co., Ltd.)

  9) FH105 (talc, manufactured by Fuji Talc)

  10) 5X (silica, manufactured by Tatsumori)

  11) KS7710 (antifoaming agent, compound type silicone oil, polydimethylsiloxane, manufactured by Shin-Etsu Chemical Co., Ltd.)

  12) Ethyl carbitol acetate (diethylene glycol monoethyl ether acetate, solvent, manufactured by Daicel)

Example 1
15 parts by weight of the acrylic polymer 1 obtained in Synthesis Example 1, 5 parts by weight of DPHA (acrylic monomer, dipentaerythritol hexaacrylate, manufactured by Daicel Ornex) and TPO (photopolymerization initiator that is a photoradical generator), 2 parts by weight of BASF Japan), 8 parts by weight of 157S (bisphenol A novolac type epoxy resin, Mitsubishi Chemical, solid at 25 ° C.), and 40 parts by weight of CR-50 (titanium oxide, Ishihara Sangyo) , 10 parts by weight of FH105 (talc, manufactured by Fuji Talc), 1 part by weight of KS7710 (antifoaming agent, compound type silicone oil, polydimethylsiloxane, manufactured by Shin-Etsu Chemical Co., Ltd.), and ethyl carbitol acetate (diethylene glycol monoethyl ether) 30 parts by weight of acetate, solvent, manufactured by Daicel) Rentaro AREs-310, were mixed for 3 minutes at manufactured Thinky Corporation), were mixed by three rolls to obtain a mixture. Then, the resist material which is a photosensitive composition was obtained by degassing the obtained mixture for 3 minutes using the said mixer.

(Examples 2-6 and Comparative Examples 1-5)
A resist material that is a photosensitive composition was obtained in the same manner as in Example 1 except that the type and blending amount of the materials used were changed as shown in the following table.

(Evaluation)
(1) Production of measurement sample An FR-4 substrate having a size of 80 mm × 90 mm and a thickness of 0.8 mm was prepared. On this substrate, a resist material was printed with a solid pattern using a 100 mesh polyester bias plate by a screen printing method. After printing, it was dried in an oven at 80 ° C. for 20 minutes to form a resist material layer on the substrate. Next, using a UV irradiation device through a photomask having a predetermined pattern, UV light having a wavelength of 365 nm is applied to the resist material layer at a UV intensity of 100 mW / cm ² so that the irradiation energy is 400 mJ / cm ^2. Irradiated for 2 seconds. Thereafter, in order to remove the resist material layer in the unexposed area and form a pattern, the resist material layer was dipped in a 1% by weight aqueous solution of sodium carbonate and developed to form a resist film on the substrate. Thereafter, the resist film was post-cured by heating in an oven at 150 ° C. for 1 hour to obtain a resist film as a measurement sample. The thickness of the obtained resist film was 20 μm.

(2) Heat resistant yellowing prevention (heat discoloration prevention, heat resistance)
The measurement sample was put in a heating oven and heated at 270 ° C. for 5 minutes.

  Using a color / color difference meter (“CR-400” manufactured by Konica Minolta), L *, a *, and b * of the evaluation sample before heat treatment were measured. Further, L *, a *, and b * of the evaluation sample after the heat treatment were measured, and ΔE * ab was obtained from these two measured values. From ΔE * ab of the evaluation sample after the heat treatment, the heat yellowing prevention property was determined according to the following criteria. In addition, there was a tendency that yellowing progressed before and after heating as ΔE * ab was larger.

[Criteria for heat-resistant yellowing prevention]
○: ΔE * ab is 0.5 or less Δ: ΔE * ab exceeds 0.5 and 1 or less ×: ΔE * ab exceeds 1

(3) Heat-resistant reflectance retention property A measurement sample was put in a heating oven and heated at 270 ° C. for 5 minutes.

    Using a color / color difference meter ("CR-400" manufactured by Konica Minolta Co., Ltd.), the Y value of the evaluation sample before and after the heat treatment is measured, and the heat resistance is determined from the Y value difference (Y value before heat treatment-Y value after heat treatment). Reflectivity retention was determined according to the following criteria.

[Criteria for heat-resistant reflectance retention]
○: Y value difference is 0.2 or less Δ: Y value difference is more than 0.2, 1 or less ×: Y value difference is more than 1

(4) Light resistance An ultraviolet ray having a wavelength of 365 nm was irradiated for 10 seconds at an ultraviolet illuminance of 100 mW / cm ² so that the irradiation energy was 1000 mJ / cm ² .

  Using a color / color difference meter ("CR-400" manufactured by Konica Minolta Co., Ltd.), L *, a *, and b * of the evaluation sample before being subjected to ultraviolet treatment were measured. Further, L *, a *, and b * of the evaluation sample after the ultraviolet treatment were measured, and ΔE * ab was obtained from these two measured values. The light resistance was determined according to the following criteria from ΔE * ab of the evaluation sample after the ultraviolet treatment.

[Criteria for light resistance]
○: ΔE * ab is 0.5 or less Δ: ΔE * ab exceeds 0.5 and 1 or less ×: ΔE * ab exceeds 1

(5) Film adhesion A resist material obtained in a solid pattern on a FR-4 substrate having a size of 80 mm × 90 mm and a thickness of 0.8 mm by a screen printing method using a 100 mesh polyester bias plate. Printed. After printing, the substrate was dried in an oven at 80 ° C. for 20 minutes to form a resist material layer (resist film) on the substrate and allowed to cool to room temperature.

  In the substrate on which the resist film was formed, the negative film was pressed against the resist film, and then the negative film was peeled off. The film sticking property was determined according to the following criteria from the state of film sticking when the negative film was peeled off.

[Criteria for film sticking property]
○: There is no residue on the resist film when the film is peeled. Δ: A slight mark is left on the resist film when the film is peeled. X: A trace is clearly left on the resist film when the film is peeled off.

  The results are shown in Table 1 below.

DESCRIPTION OF SYMBOLS 1 ... LED device 2 ... Board | substrate 2a ... Surface 3 ... Resist film 3a ... Surface 4a, 4b ... Electrode 7 ... LED chip 7a ... Lower surface 8a, 8b ... Terminal 9a, 9b ... Solder

Claims (7)

A polymerizable polymer having a carboxyl group;
A photopolymerization initiator;
An epoxy compound that is not liquid at 25 ° C .;
Titanium oxide,
Including an inorganic filler different from titanium oxide,
As the epoxy compound that is not liquid at 25 ° C., a bisphenol A novolac type epoxy compound, a biphenyl type epoxy compound, or an epoxy compound having a triazine skeleton,
The photosensitive composition whose content of the said titanium oxide is 5 weight% or more.   The total content of the bisphenol A novolac type epoxy compound, the biphenyl type epoxy compound, and the epoxy compound having a triazine skeleton is 1 part by weight or more and 50 parts by weight or less with respect to 100 parts by weight of the titanium oxide. The photosensitive composition as described in any one of.   The photosensitive composition of Claim 1 or 2 containing a rutile type titanium oxide as said titanium oxide.   The photosensitive composition of any one of Claims 1-3 containing a talc or a silica as the said inorganic filler.   The photosensitive composition of any one of Claims 1-4 used in order to form a soldering resist film. A printed wiring board body having a circuit on its surface;
A solder resist film disposed on the surface of the printed wiring board body on which the circuit is provided;
The printed wiring board whose said soldering resist film is a hardened | cured material film of the photosensitive composition of any one of Claims 1-5.   The printed wiring board of Claim 6 provided with the optical semiconductor element arrange | positioned above the surface in which the said circuit of the said printed wiring board main body was provided.

Images