JP4547225B2 - Photocurable / thermosetting resin composition and optical / electrical hybrid substrate - Google Patents

Description

  The present invention relates to a photocurable / thermosetting resin composition for an optical waveguide material using a polymer material. Specifically, the present invention has excellent storage stability and can be easily patterned with existing alkali development equipment. It can also be used as a solder resist because of its excellent impact resistance, heat resistance, adhesion, electrical insulation and the like. In addition, photo-curing and thermosetting resin compositions for optical waveguide materials that have low optical loss as optical waveguide materials, have excellent storage stability, and can be used for various optical integrated circuits or optical wiring boards. And a thermosetting dry film, a cured product thereof, and an optical / electrical hybrid substrate.

  In recent years, in order to make a computer that can perform higher-speed processing, the clock frequency of the CPU tends to increase more and more than 1 GHz order has now appeared. As a result, there is a part where high-frequency current flows in the copper electrical wiring on the printed circuit board in the computer, so that malfunctions may occur due to the generation of noise, and electromagnetic waves may be generated, adversely affecting the surroundings. Is a problem.

  In order to solve such a problem, a part of the electrical wiring made of copper on the printed board is replaced with an optical wiring made of an optical fiber or an optical waveguide, and an optical signal is used instead of the electrical signal.

  From the viewpoint of high-density mounting or miniaturization, it is desirable to make an optical / electrical hybrid board in which electrical wiring and optical wiring are stacked on the same board. Has been proposed (see, for example, Patent Document 1). However, when an optical fiber is used as an optical wiring, due to its flexibility, it cannot be applied to a complicated-shaped optical wiring, resulting in a low degree of freedom in design, and cannot support high-density wiring or downsizing of a substrate. There is a problem.

  For this reason, several configurations of optical / electrical hybrid boards using so-called optical waveguides that propagate the light by utilizing the refractive index difference between the core composition and the cladding composition as optical wiring on the electrical wiring board have been proposed. Yes. So far, many studies have been made on polymer waveguides that allow simple fabrication methods to be selected using inexpensive materials. For example, an optical waveguide material in which a polymer material having excellent transparency such as polystyrene is used as a core and a polymer material having a refractive index lower than that of the core material is used as a cladding (see, for example, Patent Document 2) is heat resistant. Disadvantages such as lack of sex have been pointed out. On the other hand, a low-loss, high-heat-resistant optical waveguide material using polyimides with high heat resistance has been realized (see, for example, Patent Document 3). However, in these methods, when forming the core structure on the surface of the clad layer, it is necessary to form a core pattern using a photoresist for each sheet or to perform uneven processing by reactive ion etching, thereby reducing cost and productivity. There was a problem.

  Further, application of a method using a semiconductor process and a method using a photosensitive polymer or a resist can be given. In particular, a method of forming a waveguide by forming a core using a photosensitive polymer includes a method of forming a pattern by irradiating ultraviolet rays through a pattern film, and the manufacturing method is simple and suitable for cost reduction. Yes.

  For this reason, an alkali development type optical waveguide resin composition using an ethylenically unsaturated group-containing carboxylic acid resin has been proposed (for example, see Patent Document 4), but a thermosetting component is essential. Therefore, there is a problem that sufficient heat resistance cannot be obtained and the impact resistance, solvent resistance, and chemical resistance are inferior. Further, a radiation curable resin composition for an optical waveguide containing a polymer having a carboxyl group, a compound having a polymerizable reactive group, and a cationic polymerization initiator has also been proposed (see, for example, Patent Document 5). Therefore, there is a problem that sufficient adhesion and electrical insulation cannot be obtained.

  In order to improve various properties, the photocurable / thermosetting resin composition for an optical waveguide usually contains a polyfunctional epoxy compound having two or more epoxy groups as a thermosetting component. However, since this polyfunctional epoxy compound has high reactivity, the photocurable / thermosetting resin composition containing the polyfunctional epoxy compound has short storage stability, and it may be difficult to form a one-component composition. Therefore, it is necessary to use a two-part composition of a curing agent solution mainly composed of a polyfunctional epoxy compound and a main agent solution mainly composed of a photosensitive resin and blended with a curing accelerator and the like, and these must be mixed and used at the time of use. There was a problem in terms of workability.

A photo-curable / thermosetting resin composition containing a polyfunctional epoxy compound has a short storage stability even in the form of a dry film, and needs to be stored frozen at 0 ° C. or less, and is stable at room temperature. There was a big problem. Moreover, when using a dry film, it is necessary to return the temperature to room temperature, which raises a problem in terms of workability. Furthermore, a photo-curable / thermosetting resin composition for optical waveguides containing a polyfunctional epoxy compound is cured by heat and curing after exposure and development, and has excellent properties such as hardness by a crosslinking reaction of the polyfunctional epoxy compound. Although a film can be obtained, on the other hand, if the crosslinking proceeds too much, the film may be cured and contracted to cause cracks.
JP-A-3-29905 (Claims) JP-A-2-181103 (Column 5-6) JP-A-6-265738 (page 3-5, FIG. 1) JP 2003-149475 A (Claims) JP 2003-195079 A (Claims)

  The object of the present invention is as a photocurable / thermosetting resin composition for optical waveguide materials, has excellent storage stability, can be easily patterned with existing alkali development equipment, impact resistance, heat resistance, An object of the present invention is to provide an optical waveguide forming resin composition excellent in adhesion, electrical insulation, crack resistance, and the like, an optical waveguide material produced using the same, and an optical waveguide forming method. In addition, it can be used as a solder resist, has low optical loss, can simplify the manufacturing process, and has excellent optical characteristics. Optical curability and thermosetting for optical waveguide materials that can be used for optical wiring boards. The object is to provide a resin composition.

In order to achieve the above object, the basic aspect of the present invention includes : (a) an optical waveguide and a solder resist layer; (b) an optical waveguide and an intermediate insulating layer; A resin composition used in combination with any combination of an optical waveguide, a solder resist layer and an intermediate insulating layer , wherein (A) the acid value is 40 to 250 mg KOH / g, and the weight average molecular weight is 2,000. A specific carboxyl group-containing resin having no aromatic ring, which is a linear polymer of ˜50,000, (B) a reactive diluent that is photocured to insolubilize the carboxyl group-containing resin (A) in a dilute aqueous alkali solution; (C) a photopolymerization initiator, (D) an oxetane resin having two or more oxetanyl groups in one molecule as a thermosetting component, and (E) a resin composition containing a thermosetting accelerator is stable in storage. It can be easily formed with existing alkali development equipment, and it can be used as a solder resist because of its excellent heat resistance, adhesion, and electrical insulation, and the refractive index can be freely adjusted by changing the resin composition. The present invention has been completed by finding that it is easily controllable and useful as an optical waveguide material and an optical waveguide manufacturing method.
By using a linear polymer having an acid value of 40 to 250 mgKOH / g and a weight average molecular weight of 2,000 to 50,000, the developability with an aqueous alkali solution is stable. And a cured product having excellent impact resistance and crack resistance is provided. Furthermore, since the carboxyl group-containing resin (A) has an ethylenically unsaturated double bond, development resistance and sensitivity are improved, and pattern formation can be easily and accurately performed with existing alkali development equipment. Can also be improved.
Here, in the present invention, the “photocurable / thermosetting resin composition” and the “photocurable / thermosetting dry film” are respectively “photocurable and thermosetting resin composition” and “ It means “photocurable and thermosetting dry film”.

Further, as another aspect , at least one of a lower cladding layer, a core layer, and an upper cladding layer of an optical waveguide constituting an optical / electrical hybrid substrate, and a solder resist layer or an intermediate insulation constituting the optical / electrical hybrid substrate and a layer, any light-electric hybrid board type printed wiring board ing formed from the photocurable and thermosetting resin composition Ru are provided.

The photocurable / thermosetting resin composition for the optical waveguide material of the present invention has excellent storage stability, can be easily patterned with existing equipment, and has impact resistance, heat resistance, adhesion, electricity The optical waveguide cladding layer and the optical waveguide core layer can be formed by an easy manufacturing process with excellent insulation and the like, and with little optical loss.
In addition, the use of inorganic fillers, especially nano-particle fillers, has the same effect of improving properties as conventionally used fillers, and also reduces optical properties such as light transmission as an optical waveguide material. It is also possible to adjust physical properties such as elastic modulus, glass transition temperature, and linear expansion coefficient. In other words, it is possible to provide a composition that can be applied to optical waveguides and solder resists that have even better heat resistance, reflow resistance, solvent resistance, and chemical resistance, and provide optical / electrical hybrid substrates at low cost and high productivity. can do.

Photocurable and thermosetting resin composition of the present invention constitutes a light-electric hybrid board, (a) an optical waveguide and the solder resist layer, (b) an optical waveguide and the intermediate insulating layer, (c) an optical waveguide, A resin composition used in combination with any combination of a solder resist layer and an intermediate insulating layer , wherein (A) the acid value is 40 to 250 mg KOH / g, and the weight average molecular weight is 2,000 to 50, A specific carboxyl group-containing resin having no aromatic ring, which is a linear polymer of 000, (B) a reactive diluent that is photocured to insolubilize the carboxyl group-containing resin (A) in a dilute alkaline aqueous solution, (C It contains a photopolymerization initiator, (D) an oxetane resin having two or more oxetanyl groups in one molecule as a thermosetting component, and (E) a thermosetting accelerator. The refractive index is changed by changing the resin composition. Freely, and easily controlled. Further, by using the carboxyl group-containing resin (A), an unexposed portion can be removed with a dilute alkaline aqueous solution, and an oxetane resin (D) having two or more oxetanyl groups in one molecule is further obtained. By containing, the heat-cured coating film can give a cured product that is extremely excellent in impact resistance, solvent resistance, and chemical resistance and has characteristics as a solder resist layer.
Hereinafter, the details of each component of the photocurable and thermosetting resin composition according to the present invention will be described.

The carboxyl group-containing resin used in the photocurable and thermosetting resin composition of the present invention (A) has an acid value containing a carboxyl group in the molecular is 40~250mgKOH / g, and the weight A specific linear polymer having no aromatic ring and having an average molecular weight of 2,000 to 50,000, and further containing a carboxyl group having an ethylenically unsaturated double bond in the molecule (A ′) Is more preferable in terms of photocurability and development resistance.
Specifically, a resin such as listed below.

(1) A carboxyl group-containing linear polymer (A) obtained by copolymerization of an unsaturated carboxylic acid and a compound having an unsaturated double bond other than that,
(2) A carboxyl group-containing photosensitive ray obtained by partially adding an ethylenically unsaturated group as a pendant to a copolymer of an unsaturated carboxylic acid and another compound having an unsaturated double bond. Polymer (A ′),
(3) A second product produced by reacting a compound having an epoxy group and an unsaturated double bond in one molecule with a copolymer of another compound having an unsaturated double bond with an unsaturated monocarboxylic acid. Carboxyl group-containing photosensitive linear polymer (A ′) obtained by reacting a saturated or unsaturated polybasic acid anhydride with a primary hydroxyl group,
(4) A compound having a hydroxyl group and an unsaturated double bond in one molecule is reacted with a copolymer of an acid anhydride having an unsaturated double bond and another compound having an unsaturated double bond. The resulting carboxyl-containing photosensitive linear polymer (A ′ ).
Such linear polymer backbone with no aromatic ring in the copolymerization system, without causing the light absorption by such as yellowing, can be suitably used for an optical waveguide.

Since the carboxyl group-containing resin (A) as described above has a large number of free carboxyl groups in the side chain of the backbone polymer, development with a dilute alkaline aqueous solution is possible.
The acid value of such a carboxyl group-containing resin (A) is in the range of 40 to 250 mgKOH / g, more preferably in the range of 80 to 120 mgKOH / g. If the acid value of the carboxyl group-containing resin is less than 40 mgKOH / g, alkali development becomes difficult. On the other hand, if it exceeds 250 mgKOH / g, dissolution of the exposed area by the developer proceeds and the line becomes thinner than necessary. Depending on the case, the exposed portion and the unexposed portion are not distinguished from each other by dissolution and peeling with a developer, which makes it difficult to draw a normal resist pattern.
Moreover, the weight average molecular weight of such a carboxyl group-containing resin (A) is in the range of 2,000 to 50,000, preferably 5,000 to 20,000. A weight average molecular weight of less than 2,000 is not preferable because the touch-drying property of the coating film is lowered and the impact resistance of the cured product is hardly obtained. On the other hand, when the weight average molecular weight exceeds 50,000, the developability is lowered, which is not preferable.
The compounding quantity of the said carboxyl group containing resin (A) is 20-60 mass% in all the compositions, Preferably it is 30-50 mass%. When the amount is less than the above range, the alkali-soluble component is insufficient, and it becomes difficult to obtain a desired waveguide shape by the development process, or the strength of the cured product is lowered, which is not preferable. On the other hand, when the amount is larger than the above range, other components are insufficient, and the sensitivity is lowered or the cured product properties are lowered.

The reactive diluent (B) used in the present invention is used for photocuring and insolubilizing the carboxyl group-containing resin in a dilute alkaline aqueous solution. Typical examples thereof include hydroxyethyl (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and polyethylene. Glycol di (meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentanyl di (meth) acrylate , EO-modified phosphoric acid di (meth) acrylate, allylated cyclohexyl di (meth) acrylate, isocyanurate di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaeryth Tall tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, PO modified trimethylolpropane tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, propionic acid modified di Examples include reactive diluents such as pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and caprolactone-modified dipentaerythritol hexa (meth) acrylate.
In addition, in this specification, (meth) acrylate is a term that collectively refers to acrylate, methacrylate, and mixtures thereof, and the same applies to other similar expressions.

  As a compounding quantity of these reactive diluents (B), 5-100 mass parts is preferable with respect to 100 mass parts of the said linear polymer (A) containing a carboxyl group, Most preferably, it is 5-50 mass parts. is there. When the component (B) is less than 5 parts by mass, sufficient curability cannot be obtained, and the designed waveguide shape cannot be obtained. On the other hand, when the amount is 100 parts or more, it is not preferable because the dryness to the touch is deteriorated or inconvenience is caused when a dry film is formed.

  As a photoinitiator (C) used in this invention, the photoinitiator generally used in the photopolymerizable composition can be used. Typical examples thereof include benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy. Acetophenones such as 2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1 -Aminoacetophenones such as 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1; 2-methylanthraquinone, 2-ethylanthraquinone, 2-tertiarybutylanthraquinone Anthraquinones such as 1-chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone and 2,4-diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal Benzophenones such as benzophenone; or xanthones; (2,6-dimethoxybenzoyl) -2,4,4-pentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4 , 6-trimethylbenzoyldiphenylphosphine oxide, phosphine oxides such as ethyl-2,4,6-trimethylbenzoylphenyl phosphinate, and the like. Initiator (C) may be used alone or in combination of two or more.

  The compounding quantity of these photoinitiators (C) is 0.1-10 mass% in all the compositions, Preferably it is 0.2-5 mass%. When the blending amount is less than 0.2% by mass of the total amount of the composition, the photocurability is lowered, and it becomes difficult to form a desired optical waveguide shape, which is not preferable. On the other hand, if it exceeds 10% by mass, it may adversely affect the transmission loss of the optical waveguide, and this is not preferable because it causes a higher cost.

The oxetane resin (D) having two or more oxetanyl groups in one molecule used in the present invention is generally an oxetane alcohol obtained by reacting a trimethylol compound such as trimethylolpropane with an alkyl carbonate, It can be synthesized by an etherification reaction with a functional alcohol or a polyphenol or an esterification reaction with a polyfunctional carboxylic acid, and examples thereof include bisoxetanes represented by the following general formula (1).







In the general formula (1), R ¹ is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ² is a linear or branched saturated hydrocarbon having 1 to 12 carbon atoms, 2 to 2 carbon atoms. 12 linear or branched unsaturated hydrocarbons, aromatic hydrocarbons represented by the following formulas (I), (II), (III), (IV) and (V), formulas (VI) and (VII A group having a divalent valence selected from linear or cyclic alkylenes containing a carbonyl group represented by formula (VIII) and aromatic hydrocarbons containing a carbonyl group represented by formulas (VIII) and (IX) It is.

In the formula, R ³ represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group, or an aralkyl group, and R ⁴ represents —O—, —S—, —CH ₂ —, —NH—, — SO ₂ −,
_{-CH (CH 3) -, -} C (CH 3) 2 -, or -C _{(CF 3) 2} - represents, ^{R 5} represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

In the formula, n represents an integer of 1 to 12.

Moreover, as a representative example of a compound having three or more oxetane rings in the molecule, in addition to a compound represented by the following general formula (2), oxetane and novolak resin, poly (p-hydroxystyrene), cardo type Examples include bisphenols, calixarenes, calixresorcinarenes, and etherified products with resins having a hydroxyl group such as silsesquioxane. In addition, a copolymer of an unsaturated monomer containing an oxetane ring and an alkyl (meth) acrylate is also included.



In the general formula (2), R ¹ has the same meaning as described above, and R ⁶ represents a hydroxyl group-containing resin residue of the etherified product, represented by the following formulas (X), (XI), and (XII). A C1-C12 branched alkylene group, and aromatic hydrocarbons represented by the formulas (XIII), (XIV), and (XV). M represents the number of functional groups bonded to the residue R ⁶ , and is an integer of 3 or more, preferably an integer of 3 to 500.

In the formula, R ⁷ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group.

  These oxetane resins (D) improve the adhesion, heat resistance, and electrical insulation properties of the optical waveguide coating film by a thermosetting reaction. As a mixture ratio of oxetane resin (D), it is 0.5-2.0 equivalent with respect to 1 equivalent of carboxyl groups of the said carboxyl group-containing resin (A), Preferably it is 0.8-1.6 equivalents. It is a ratio. When the blending ratio of the oxetane resin component is less than 0.5 equivalent with respect to 1 equivalent of the carboxyl group of the carboxyl group-containing resin (A), the crosslinking density of the cured coating film is lowered, and the solder heat resistance and reflow resistance are reduced. It tends to be low. On the other hand, if it exceeds 2.0 equivalents, the developability of the dried coating film is lowered, and the desired waveguide shape cannot be obtained.

  Examples of the curing accelerator (E) used in the present invention include tertiary amines, tertiary amine salts, quaternary onium salts, tertiary phosphines, imidazole derivatives or crown ether complexes (for example, 18-crown-6 / potassium phenoxide). , Potassium benzoether, KCl, KBr, ammonium acetate, etc.), and these may be used alone or in admixture of two or more. In addition, phosphonium ylide can also be used. The tertiary amine includes triethylamine, tributylamine, DBU (1,8-diazabicyclo [5.4.0] undec-7-ene), DBN (1,5-diazabicyclo [4.3.0] non-5- En), DABCO (1,4-diazabicyclo [2.2.2] octane), pyridine, N, N'-dimethyl-4-aminopyridine and the like. Examples of the tertiary amine salt include U-CAT series manufactured by San Apro Co., Ltd. Furthermore, a quaternary onium salt formed by an addition reaction of a tertiary amine or tertiary phosphine with a carboxylic acid or a strongly acidic phenol can also be used as a reaction accelerator. These may be any method in which a quaternary salt is formed before addition to the reaction system, or each is added separately to form a quaternary salt in the reaction system. Specific examples include tributylamine acetate obtained from tributylamine and acetic acid, and triphenylphosphine acetate formed from triphenylphosphine and acetic acid. Examples of the quaternary onium salt include ammonium salts, phosphonium salts, arsonium salts, stibonium salts, oxonium salts, sulfonium salts, selenonium salts, stannonium salts, iodonium salts, and the like. Particularly preferred are quaternary ammonium salts and quaternary phosphonium salts. Specific examples of quaternary ammonium salts include tetra-n-butylammonium chloride (TBAC), tetra-n-butylammonium bromide (TBAB), tetra-n-butylammonium iodide (TBAI), and tetra-n-butyl. Ammonium acetate (TBAAc) etc. are mentioned. Specific examples of the quaternary phosphonium salt include tetra-n-butylphosphonium chloride (TBPC), tetra-n-butylphosphonium bromide (TBPB), tetra-n-butylphosphonium iodide (TBBI), and tetraphenylphosphonium chloride (TPPC). ), Tetraphenylphosphonium bromide (TPPB), tetraphenylphosphonium iodide (TPPI), ethyltriphenylphosphonium bromide (ETPPB), ethyltriphenylphosphonium acetate (ETPPAc), and the like. The tertiary phosphine may be a trivalent organic phosphorus compound having an alkyl group having 1 to 12 carbon atoms or an aryl group. Specific examples include triethylphosphine, tributylphosphine, triphenylphosphine and the like. Examples of imidazole derivatives include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1- (2- And cyanoethyl) -2-ethyl-4-methylimidazole. Specific examples of commercially available products include 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, and 2P4MHZ manufactured by Shikoku Kasei Co., Ltd. Moreover, as a thing which aims at stability improvement with time, Asahi Ciba Co., Ltd. product NOVACURE HX-3721, HX-3748, HX-3741, HX-3088, HX-3722, HX-3742, HX-392HP, HX-3941HP, HX-3613 etc. are also mentioned. As the phosphonium ylide, known compounds can be used as long as they are compounds obtained by the reaction of a phosphonium salt and a base, but a highly stable compound is preferred from the viewpoint of ease of handling. Specific examples include (formylmethylene) triphenylphosphine, (acetylmethylene) triphenylphosphine, (pivaloylmethylene) triphenylphosphine, (benzoylmethylene) triphenylphosphine, (p-methoxybenzoylmethylene) triphenyl. Phosphine, (p-methylbenzoylmethylene) triphenylphosphine, (p-nitrobenzoylmethylene) triphenylphosphine, (naphthoyl) triphenylphosphine, (methoxycarbonyl) triphenylphosphine, (diacetylmethylene) triphenylphosphine, (acetylcyano) ) Triphenylphosphine, (dicyanomethylene) triphenylphosphine, and the like.

  The usage-amount of a hardening accelerator (E) is the range of 0.1-25 mol% with respect to 1 mol of oxetanyl groups, More preferably, it is 0.5-20 mol%, More preferably, it is 1-15 mol %. When the amount of the curing accelerator used is less than 0.1 mol% with respect to the oxetanyl group, the reaction does not easily proceed at a practical rate. Is not preferable in terms of economy.

The photocurable / thermosetting resin composition of the present invention, or the photocurable / thermosetting dry film is used to adjust the linear expansion coefficient of the cured product or to improve the coating properties such as heat resistance. (F) An inorganic filler can be blended. Examples of such inorganic fillers (F) include known and commonly used fillers such as crystalline silica, fused silica, glass powder, talc, clay, magnesium carbonate, calcium carbonate, natural mica, synthetic mica, aluminum hydroxide, sedimentation. And inorganic pigments such as basic barium sulfate, barium titanate, iron oxide, non-fibrous glass, asbestos, mineral wool, aluminum silicate, calcium silicate, zinc white, and titanium oxide.
The photocurable / thermosetting resin composition or the photocurable / thermosetting dry film of the present invention can be used as a solder resist and a material for an optical waveguide, but when used as a solder resist, the inorganic filler The average particle size of (F) is 20 μm or less, more preferably 10 μm or less, from the film thickness of a general solder resist.
On the other hand, when used for an optical waveguide material, since the wavelengths generally used for optical waveguides are 850 nm, 1300 nm, and 1550 nm, the average particle size of the inorganic filler (F) is 800 nm or less, preferably 400 nm or less, More preferably, it is 100 nm or less and the maximum particle size is 850 nm or less, since the transparency of the optical waveguide is increased and the optical loss is reduced.

Thus, as the fine inorganic filler (F) used as an optical waveguide material, NANOCRYL (trade name) XP 0396, XP 0596, manufactured by Hanse-Chemie, in which nano silica is dispersed in the reactive diluent (B), XP 0733, XP 0746, XP 0765, XP 0768, XP 0953, XP 0954, XP 1045 (all product grade names), XP21 / 1442, XP21 / 1500, XP21 / 1306, XP21 / 0568, XP21 / 0568, XP21 / 1192, XP21 / 1364, XP21 / 1425, XP21 / 0140, XP21 / 1465, XP21 / 0638, XP21 / 0568, XP21 / 1471, XP21 / 0928, XP21 / 0528, XP21 / 1468, XP21 / 0687, XP21 / 1515, XP21 / 1472, XP21 / 0942, XP21 / 1447, XP21 / 1481 (all are prototype grade names) and the like.
Further, organosilica sol PMA-ST (trade name) manufactured by Nissan Chemical Industries, Ltd. in which nano silica is dispersed in an organic solvent described later can also be used.
Furthermore, an epoxy resin can be used as long as the storage stability, which is the object of the present invention, is not reduced, and NANOPOX (trade name) XP 0516, XP 0525 manufactured by Hanse-Chemie, in which nano silica is dispersed in the epoxy resin. , XP 0314 (all are product grade names), XP22 / 0543, XP22 / 0531, XP22 / 0540 (all are prototype grade names).
The inorganic filler (F) dispersed in the reactive diluent (B) or the like is less likely to cause secondary aggregation of the inorganic filler (F) during raw material storage, and is uniform in the resin composition. And can be preferably used.

  The blending ratio of these inorganic filler components is suitably 0 to 200 parts by weight, preferably 10 to 100 parts by weight, more preferably 20 to 50 parts by weight with respect to 100 parts by weight of the carboxyl group-containing resin (A). Part. When the blending ratio of the filler component exceeds 200 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin (A), the applicability and fluidity of the composition cannot be obtained, or the smoothness of the cured product Is not preferable because it cannot be obtained.

Furthermore, the photocurable / thermosetting resin composition or the photocurable / thermosetting dry film of the present invention may contain (G) an organic solvent, if necessary. The organic solvent (G) contains the carboxyl group-containing resin (A), the reactive diluent (B), the photopolymerization initiator (C), the oxetane resin (D), and the curing accelerator (E). It is used for dissolving the component contained and liquefying it or adjusting the viscosity according to the coating method. Further, when a photocurable / thermosetting dry film is prepared, it is used for preparing a uniform composition and uniformly applying it to a support film.
Examples of these organic solvents (G) include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methylcellosolve, butylcellosolve, carbitol, methylcarbitol, butylcarbitol, Glycol ethers such as propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, tripropylene glycol monomethyl ether; ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol Acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether Acetates, esters such as propylene carbonate; octane, aliphatic hydrocarbons decane, petroleum ether, petroleum naphtha, and petroleum solvents such as solvent naphtha, organic solvents conventionally known can be used. In particular, an organic solvent having a boiling point of 150 ° C. or less can be preferably used for forming a dry film. These organic solvents can be used alone or in combination of two or more.
The amount of these organic solvents used is the carboxyl group-containing resin (A), the reactive diluent (B), the photopolymerization initiator (C), the oxetane resin (D), and the curing accelerator (E). The amount is preferably in the range of 10 to 200 parts by mass with respect to 100 parts by mass of the photosensitive layer component. In the case of forming a dry film, the temperature condition for scattering the organic solvent is 50 ° C to 150 ° C, more preferably 70 ° C to 130 ° C. The amount of the solvent remaining after drying is preferably less than 30 parts by mass, more preferably less than 10 parts by mass with respect to 100 parts by mass of the photosensitive layer component.

  In addition, the photocurable / thermosetting resin composition or the photocurable / thermosetting dry film of the present invention may be a silicone-based, hydrocarbon-based, acrylic-based or other antifoaming agent; Dispersants such as coupling agents such as titanates and alumina; additives such as polymer compatibilizers such as oxazoline group-containing polymers can be blended. These additives can be used alone or in combination of two or more.

  The photocurable / thermosetting resin composition of the present invention is, for example, adjusted in viscosity with the organic solvent (G) to a viscosity suitable for the coating method, and dip-coated, flow-coated, or roll-coated on the substrate. It is applied by a method such as bar coater method, screen printing method, curtain coating method, etc., and the organic solvent contained in the composition is evaporated and dried (temporary drying) at a temperature of about 60 to 100 ° C. A film can be formed. Moreover, the resin insulating layer used as a clad layer or a core layer can be formed by apply | coating the said composition on a plastic film, and sticking on a base material what dried and made the dry film. After that, by a contact method (or non-contact method), exposure is selectively performed with actinic rays through a photomask having a pattern formed, and an unexposed portion is developed with a dilute alkaline aqueous solution (for example, 0.3 to 3% sodium carbonate aqueous solution). Thus, the pattern of the cladding layer and the core layer is formed. Furthermore, for example, by heating to a temperature of about 140 to 180 ° C. and thermosetting, the carboxyl group of the carboxyl group-containing resin (A) and an oxetane resin having two or more oxetanyl groups in one molecule (D) The oxetanyl group can react to form a cured coating film excellent in various properties such as heat resistance, solvent resistance, acid resistance, moisture absorption resistance, PCT resistance, adhesion, and electrical characteristics.

In the production of the photocurable / thermosetting dry film of the present invention, the photosensitive layer components are dissolved in the organic solvent (G) as described above, adjusted to a viscosity suitable for the coating method, and placed on an appropriate support film. The photosensitive layer after drying has a thickness of 10 to 150 μm and is coated with a film coater or the like so that the variation in film thickness is within ± 10%, and then dried at, for example, about 60 to 140 ° C. By dry-drying the organic solvent contained in the composition at a temperature of 120 ° C., a dry film having a photosensitive layer composed of a tack-free dry film is formed. At this time, if the variation in the film thickness after drying exceeds ± 10%, the smoothness is lost and the optical loss is increased, which is not preferable.
Examples of the support film include a film having a film thickness of about 15 to 125 μm and having flexibility such as polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), polycarbonate, polyether sulfone, and polyvinyl chloride. Used.
Examples of the method for applying the photosensitive layer component to the support include a knife coater method, a comma coater method, a die coater method, a gravure coater method, a roll coater method, and a spray coater method.
Furthermore, it is desirable to laminate a peelable cover film on the surface of the photosensitive layer for the purpose of preventing dust from adhering to the surface of the photosensitive layer. As the peelable cover film, for example, a film having a film thickness of about 15 to 100 μm, such as a PET film, a PP film, a PE film, or a film obtained by coating or baking these with silicone is used. The peelable condition may be any if the adhesive force between the photosensitive layer and the cover film is smaller than the adhesive force between the photosensitive layer and the support film when the cover film is peeled off. Further, in order to prevent the oxygen desensitizing action of the photocurable / thermosetting photosensitive layer and to prevent the adhesion of the photomask for pattern formation adhered during exposure, polyvinyl alcohol is further added on the photosensitive layer. A protective layer having a film thickness of about 1 to 10 μm can be formed from a water-soluble resin composition such as saponified polyvinyl acetate.

In forming an optical waveguide using the photocurable / thermosetting resin composition of the present invention, the present invention includes at least one step of forming each of the lower cladding layer, the upper cladding layer, and the core layer. After the photocurable / thermosetting resin composition is applied to a substrate or transferred as a dry film, a step of curing by exposure and subsequent heating can be used.
Thus the photocurable and thermosetting resin composition of the present invention, the lower cladding layer, upper cladding layer, and a case of using at least one core layer, the relationship between the refractive index of each part, is required to the optical waveguide By appropriately selecting the type and blending amount of each component so as to satisfy the conditions, a photocurable / thermosetting resin composition from which cured films having different refractive indexes can be obtained can be obtained. In the present invention, the photocurable / thermosetting resin composition of the present invention is used only for the core portion, and the other cladding portions are produced by a conventional photocurable / thermosetting ink composition, or The optical waveguide can also be produced using the photocurable / thermosetting resin composition of the present invention for all layers.
Although the base material used for this invention is not restrict | limited in particular, For example, a silicon substrate, a glass substrate, a glass epoxy resin substrate etc. can be used.

  Here, as an irradiation light source for photocuring the photocurable / thermosetting resin composition of the present invention or the photocurable / thermosetting dry film, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure Mercury lamps, xenon lamps or metal halide lamps are suitable. In addition, a laser light source or the like can be directly drawn as an active light source for exposure using a direct imaging method. As the dilute alkaline aqueous solution used for the development, alkaline aqueous solutions such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, ammonia and amines can be used, and sodium carbonate is particularly preferable.

  Furthermore, the photocurable / thermosetting resin composition of the present invention or the photocurable / thermosetting dry film can be used as a solder resist or an intermediate insulating layer, and the optical waveguide formed as described above. At the same time, it is also possible to manufacture an optical / electrical hybrid substrate used in an electronic circuit.

  Next, the present invention will be specifically described with reference to examples and comparative examples of the present invention. Needless to say, the present invention is not limited to the following examples. In the following, “parts” and “%” represent “parts by mass” and “mass%” unless otherwise specified.

<Synthesis Example 1>
To a 2 liter separable flask equipped with a stirrer, thermometer, reflux condenser, dropping funnel and nitrogen inlet tube, 900 g of diethylene glycol dimethyl ether and t-butyl peroxy 2-ethylhexanoate [Nippon Yushi Co., Ltd. O] 21.4 g was charged, and after raising the temperature to 90 ° C., 309.9 g of methacrylic acid, 116.4 g of methyl methacrylate, 109.8 g of lactone-modified 2-hydroxyethyl methacrylate [Daicel Chemical Industries, Ltd. Plaxel FM1] Vinyl having a carboxyl group by dropwise addition over 3 hours to diethylene glycol dimethyl ether together with 21.4 g of bis (4-t-butylcyclohexyl) peroxydicarbonate [Nippon Yushi Co., Ltd. Parroyl TCP] and further aging for 6 hours Copolymer solution Obtained. The reaction was performed under a nitrogen atmosphere.
Next, 363.9 g of 3,4-epoxycyclohexylmethyl acrylate [Cyclomer A200 manufactured by Daicel Chemical Industries, Ltd.], 3.6 g of dimethylbenzylamine, and 1.80 g of hydroquinone monomethyl ether were added to the vinyl copolymer solution. Epoxy ring-opening addition reaction was performed by raising the temperature to 0 ° C. and stirring. After 16 hours, a solution containing 53.8 wt% (nonvolatile content) of a carboxyl group-containing photosensitive linear polymer having a solid content acid value of 108.9 mgKOH / g and a weight average molecular weight of 25,000 (in terms of styrene) was obtained. It was. Hereinafter, this reaction solution is referred to as A-1 varnish.

<Example 1>
Preparation of photocurable / thermosetting resin composition for core (P-1) Jonkrill 67 (trade name, solid content acid value = 213 mgKOH / g, weight) manufactured by Johnson Polymer Co., Ltd., which is a commercially available styrene-acrylic acid resin Using the varnish (hereinafter referred to as A-2 varnish) in which the average molecular weight = 12,500 was dissolved in carbitol acetate so that the non-volatile content = 70%, the following blending components were stirred with a stirrer. Thereafter, the mixture was uniformly dispersed by kneading with a three-roll mill, and after dilution, the photocurable / thermosetting resin composition for core (P-1) was prepared by filtration.

A-2 varnish 100.0 parts Dipentaerythritol hexaacrylate 15.0 parts 2-methyl-1 [4- (methylthio) phenyl]
-2-morpholinopropan-1-one 5.0 parts phenol novolac oxetane resin (manufactured by Toagosei Co., Ltd., prototype name PNOX-1009,
Oxetane equivalent = 202) 60.0 parts Propylene glycol monomethyl ether acetate 10.0 parts BYK-310 (Surface conditioner manufactured by Big Chemie Japan) 0.3 parts

<Example 2>
Preparation of photocurable / thermosetting resin composition for upper and lower clad (P-2) The following compounding ingredients were stirred with a stirrer and then uniformly dispersed by kneading with a three roll mill, diluted and filtered. By doing so, the photocurable thermosetting resin composition (P-2) for upper and lower clads was prepared.

A-1 Varnish 100.0 parts NANOCRYL XP21 / 1364
(Nanosilica-containing monomer manufactured by Hanse-Chemie, solid content = 40%) 30.0 parts 2-methyl-1 [4- (methylthio) phenyl]
-2-morpholinopropan-1-one 5.0 parts phenol novolac oxetane resin (manufactured by Toagosei Co., Ltd., prototype name PNOX-1009,
Oxetane equivalent = 202) 60.0 parts Propylene glycol monomethyl ether acetate 10.0 parts BYK-310 (Surface conditioner manufactured by Big Chemie Japan) 0.3 parts

<Example 3>
Preparation of photocurable / thermosetting resin composition for upper and lower clad (P-3) The following compounding ingredients were stirred with a stirrer and then uniformly dispersed by kneading with a three roll mill, diluted and filtered. By doing so, the photocurable thermosetting resin composition (P-3) for upper and lower clads was prepared.

A-1 Varnish 100.0 parts Dipentaerythritol hexaacrylate 15.0 parts 2-Methyl-1 [4- (methylthio) phenyl]
-2-morpholinopropan-1-one 5.0 parts phenol novolac oxetane resin (manufactured by Toagosei Co., Ltd., prototype name PNOX-1009,
Oxetane equivalent = 202) 60.0 parts Propylene glycol monomethyl ether acetate 10.0 parts BYK-310 (Surface conditioner manufactured by Big Chemie Japan) 0.3 parts

<Example 4>
Preparation of core photocurable / thermosetting dry film (P-4) Applying the resin composition obtained in Example 1 onto a polyethylene terephthalate film using an applicator and temporarily drying at 90 ° C. for 30 minutes. Thus, a photocurable / thermosetting dry film for core (P-4) having a dry film thickness of 50 μm was produced.

<Example 5>
Preparation of photocurable / thermosetting dry films (P-5, P-6) for upper and lower clads The resin composition obtained in Example 2 was applied onto a polyethylene terephthalate film using an applicator, and 30 at 90 ° C. By preliminarily drying, a photocurable / thermosetting dry film for a lower clad with a dry film thickness of 20 μm (P-5) and a photocurable thermosetting dry film for an upper clad with a dry film thickness of 70 μm (P -6) was produced.

<Example 6>
Production of Photocurable and Thermosetting Dry Films for Upper and Lower Cladding (P-7, P-8) The resin composition obtained in Example 3 was applied onto a polyethylene terephthalate film using an applicator, and 30 at 90 ° C. By preliminarily drying, a photocurable / thermosetting dry film for a lower clad with a dry film thickness of 20 μm (P-7) and a photocurable thermosetting dry film for an upper clad with a dry film thickness of 70 μm (P -8) was produced.

<Comparative example 1>
Preparation of core photocurable / thermosetting dry film (P-9) The following compounding ingredients were stirred with a stirrer and then kneaded with a three-roll mill to make the core photocurable / thermosetting dry. The resin composition used as the base of the film was uniformly dispersed, diluted, and then filtered to prepare a resin composition. The obtained resin composition was applied onto a polyethylene terephthalate film using an applicator and temporarily dried at 90 ° C. for 30 minutes, whereby a photocurable / thermosetting dry film for core (P-9) having a dry film thickness of 50 μm. ) Was produced.

A-2 varnish 100.0 parts Dipentaerythritol hexaacrylate 15.0 parts 2-methyl-1 [4- (methylthio) phenyl]
-2-morpholinopropan-1-one 5.0 parts DEN-431 (Phenol novolac type epoxy resin (Mw = 970) manufactured by Dow Chemical Company) 60.0 parts Propylene glycol monomethyl ether acetate 10.0 parts BYK- 310 (Surface conditioner manufactured by Big Chemie Japan) 0.3 parts

<Comparative example 2>
Preparation of photocurable and thermosetting dry films (P-10, P-11) for upper and lower clads Photocurability for clads by stirring the following blending components with a stirrer and then kneading with a three roll mill -The resin composition used as the base of a thermosetting dry film was uniformly disperse | distributed, the resin composition was adjusted by filtering after dilution. The obtained resin composition was applied onto a polyethylene terephthalate film using an applicator and temporarily dried at 90 ° C. for 30 minutes, whereby a photocurable / thermosetting dry film (P- 6) and a photocurable / thermosetting dry film (P-7) for an upper clad having a dry film thickness of 70 μm.

A-1 Varnish 100.0 parts Dipentaerythritol hexaacrylate 15.0 parts 2-Methyl-1 [4- (methylthio) phenyl]
-2-morpholinopropan-1-one 5.0 parts DEN-431 (Phenol novolac type epoxy resin (Mw = 970) manufactured by Dow Chemical Company) 60.0 parts Propylene glycol monomethyl ether acetate 10.0 parts BYK- 310 (Surface conditioner manufactured by Big Chemie Japan) 0.3 parts

<Storage stability test in dry film state>
The optical waveguide cores prepared in Examples 4 to 6 and Comparative Examples 1 and 2 and the photocurable / thermosetting dry film for cladding were left at room temperature for 3 days, 5 days, and 10 days, and then the base. The dry film was transferred onto the substrate while applying appropriate heat and pressure using an atmospheric pressure hot roll crimping machine so that the film was on top. Thereafter, exposure and development were performed, and whether or not each pattern could be formed was evaluated. The results are shown in Table 1.
○: A pattern was formed after substrate transfer, exposure and development.
X: After the substrate was transferred, exposed and developed, the pattern could not be formed.

  As described above, the dry films (P-4 to 8) of Examples 4 to 6 using the oxetane resin as the thermosetting component are the dry films (P) of Comparative Examples 1 and 2 using the epoxy resin as the thermosetting component. It can be seen that the storage stability is excellent as compared with -9 to 11).

<Application Example 1>
On the substrate, the photocurable / thermosetting resin composition for cladding (P-2) of Example 2 was applied by screen printing so that the dry coating film was 20 μm, and heated at 80 ° C. for 20 minutes. The substrate on which the lower cladding layer of the optical waveguide is formed by volatilizing the organic solvent, photocuring it by exposing it from above, and performing post-curing for 30 minutes in a hot air circulation drying oven at 150 ° C. Got. Next, on this lower clad layer, the photocurable / thermosetting resin composition for core (P-1) of Example 1 was applied by screen printing so that the dry coating film would be 50 μm, and 80 ° C. Then, the organic solvent was volatilized by heating for 20 minutes, and then the upper surface was exposed through a photomask having a predetermined line pattern, and developed with a 1.0 wt% Na ₂ CO ₃ aqueous solution for 60 seconds. Then, the core layer was formed in the upper part of the lower clad layer by performing a thermosetting reaction at 150 ° C. for 60 minutes similarly to the lower clad layer. Next, the photocurable / thermosetting resin composition for cladding (P-2) of Example 2 was applied on the lower cladding layer on which the core portion was formed, and heated at 80 ° C. for 20 minutes to form an organic solvent. And then photocuring by exposing from above, followed by post-curing for 30 minutes in a hot air circulating drying oven at 150 ° C., so that the film thickness is 20 μm on the core and 70 μm on the lower cladding. A cured film for clad on the optical waveguide was formed to produce a multimode type optical waveguide. The optical waveguides thus obtained were cut into lengths between 1 cm and 5 cm, respectively, and the optical transmission loss was measured by the cutback method.

<Application Example 2>
In the application example 1, in place of the photocurable / thermosetting resin composition for clad (P-2) of example 1, the photocurable / thermosetting resin composition for clad of example 3 (P A multimode type optical waveguide was produced in the same manner except that 3) was used.
The optical waveguides thus obtained were cut into lengths between 1 cm and 5 cm, respectively, and the optical transmission loss was measured by the cutback method.

<Application Example 3>
Appropriate heat and pressure using a normal pressure hot roll crimping machine so that the base film is on top of the photocurable / thermosetting dry film (P-5) for lower clad of Example 5 on the substrate. The dry film was transferred onto the substrate while adding. Thereafter, the lower cladding layer was exposed to light and cured, and then a thermosetting reaction was performed at 150 ° C. for 60 minutes. Next, on the lower clad layer, the core photocurable / thermosetting dry film (P-4) of Example 4 is formed in the same manner as described above, using an atmospheric pressure hot roll crimping machine, and the lower clad layer. The film was transferred to the top to form a core coating film. Thereafter, exposure through a photomask having a predetermined line pattern from the upper surface of the core for a coating film was subjected to 60 seconds development at 1.0wt% _Na 2 CO ₃ aq. Then, the core layer was formed in the upper part of the lower clad layer by performing a thermosetting reaction at 150 ° C. for 60 minutes similarly to the lower clad layer. Next, the photothermographic / thermosetting dry film (P-6) for upper clad of Example 5 is placed on the lower clad layer on which the core portion is formed so that the base film faces upward. The dry film was transferred onto the substrate using a crimping machine while applying appropriate heat and pressure. The upper clad dry film is exposed and photocured to form an upper clad layer, and then a thermosetting reaction is performed at 150 ° C. for 60 minutes to form the lower clad layer, the core layer, and the upper clad layer. An optical waveguide was manufactured. The optical waveguides thus obtained were cut into lengths between 1 cm and 5 cm, respectively, and the optical transmission loss was measured by the cutback method.

<Application Example 4>
In Example 3 above, instead of the photocurable and thermosetting dry film (P-5, P-6) for the upper and lower clads of Example 5, the photocurable and thermosetting dry for the upper and lower clads of Example 6 were used. A multimode type optical waveguide was produced in the same manner except that the films (P-7, P-8) were used.
The optical waveguides thus obtained were cut into lengths between 1 cm and 5 cm, respectively, and the optical transmission loss was measured by the cutback method.

<Application comparison example 1>
In the application example 3, in place of the photocurable and thermosetting dry film for upper and lower clad (P-5, P-6) of example 5, the photocurable and thermosetting for upper and lower clad of comparative example 2 were used. The dry film (P-10, P-11) was used, and the core photocurable property of Comparative Example 1 was used instead of the core photocurable and thermosetting dry film (P-4) of Example 4. A multimode optical waveguide was produced in the same manner except that a thermosetting dry film (P-9) was used.
The optical waveguides thus obtained were cut into lengths between 1 cm and 5 cm, respectively, and the optical transmission loss was measured by the cutback method.

Performance evaluation:
(A) Solder heat resistance About the obtained multimode type optical waveguide, according to the test method of JIS C 6481, it was immersed in the molten solder of 260 degreeC accommodated in the solder tank for 30 second, and cellophane tape (brand name) was added after that A so-called peeling test was performed, in which the film was rubbed with a finger after being applied to the cured coating film, and then peeled off. One test was regarded as one cycle, and this was repeated up to three cycles at the same location. The degree of peeling of the cured coating film was visually observed and evaluated according to the following criteria. The results are shown in Table 2.
○: No peeling after tape peeling test.
X: Detachment after tape peeling test.

(B) Reflow resistance The obtained multimode type optical waveguide was passed through a reflow furnace at a temperature of 260 ° C. to visually observe whether it peeled off or swelled, and was evaluated according to the following criteria. It was shown in 2.
○: After passing through the reflow furnace, the coating film peels off and does not swell.
X: After passing through the reflow furnace, the film peels off and causes swelling.

(C) Chemical resistance The obtained multimode optical waveguide was immersed in a 10% aqueous hydrochloric acid solution for 30 minutes, and then the state of the cured coating film was visually observed and evaluated according to the following criteria. It was shown in 2.
○: No change is observed at all.
Δ: Slightly changed.
X: Remarkably changed.

(D) Solvent resistance The obtained multimode optical waveguide was immersed in propylene glycol monomethyl ether for 30 minutes, and then the state of the cured coating film was visually observed and evaluated according to the following criteria. It was shown to.
○: No change is observed at all.
Δ: Slightly changed.
X: Remarkably changed.

(E) Accuracy of core shape The obtained multi-mode optical waveguide was cut out and observed for differences in core shape at each length. The results are shown in Table 2.
○: Almost no change is observed.
Δ: A difference of ± 3 μm or more is confirmed.
X: Remarkably changed.

(F) Crack resistance The obtained multi-mode type optical waveguide substrate is put into a thermal shock tester, and a heat cycle test at −45 ° C., 15 minutes and 125 ° C., 15 minutes is performed for 300 cycles. Were observed with a microscope and examined for the presence of cracks.
○: No abnormality such as cracks.
Δ: Some cracks occurred.
X: Cracks occur throughout.

As described above, application examples 1 to 4 using oxetane resin as the thermosetting component show solder heat resistance, reflow resistance, chemical resistance, etc. equivalent to the application comparative example using epoxy resin as the thermosetting component. There was no problem with the accuracy of the core shape. Further, the crack resistance tended to be superior to that of Comparative Application Example 1 using an epoxy resin as a thermosetting component.
As described above, the photocurable / thermosetting resin composition and the photocurable / thermosetting dry film of the present invention are excellent in storage stability and have a thermosetting component as can be seen from Table 1 above. As a result, characteristics equal to or higher than those obtained when an epoxy resin was used were obtained.

Claims (5)

Used in combination with any combination of (a) optical waveguide and solder resist layer, (b) optical waveguide and intermediate insulating layer, and (c) optical waveguide, solder resist layer and intermediate insulating layer that constitute the optical / electrical hybrid substrate. A resin composition to be used,
(A) The acid value is 40 to 250 mg KOH / g and the weight average molecular weight is 2,000 to 50,000, and at least one selected from the following (1) to (4) having no aromatic ring in the main chain carboxyl group-containing resin which is a copolymer based linear polymers of,
(1) a linear polymer containing a carboxyl group obtained by copolymerization of an unsaturated carboxylic acid and a compound having an unsaturated double bond other than that,
(2) A carboxyl group-containing photosensitive ray obtained by partially adding an ethylenically unsaturated group as a pendant to a copolymer of an unsaturated carboxylic acid and another compound having an unsaturated double bond. Polymer,
(3) A second product produced by reacting a compound having an epoxy group and an unsaturated double bond in one molecule with a copolymer of another compound having an unsaturated double bond with an unsaturated monocarboxylic acid. A photosensitive linear polymer containing a carboxyl group obtained by reacting a saturated hydroxyl group with a saturated or unsaturated polybasic acid anhydride,
(4) A compound having a hydroxyl group and an unsaturated double bond in one molecule is reacted with a copolymer of an acid anhydride having an unsaturated double bond and another compound having an unsaturated double bond. The resulting photosensitive linear polymer containing carboxyl groups,
(B) a reactive diluent that is photocured to insolubilize the carboxyl group-containing resin (A) in a dilute aqueous alkali solution;
(C) a photopolymerization initiator,
(D) A photocurable thermosetting resin composition comprising an oxetane resin having two or more oxetanyl groups in one molecule as a thermosetting component, and (E) a thermosetting accelerator. 2. The photocuring property according to claim 1, wherein the carboxyl group-containing resin (A) is a carboxyl group-containing photosensitive linear polymer further having (A ′) an ethylenically unsaturated double bond. Thermosetting resin composition. Furthermore, (F) inorganic filler is contained, The photocurable and thermosetting resin composition of Claim 1 or 2 characterized by the above-mentioned. At least one of the lower clad layer, the core layer, and the upper clad layer of the optical waveguide constituting the optical / electrical hybrid substrate, and the solder resist layer or the intermediate insulating layer constituting the optical / electrical hybrid substrate, An optical / electrical hybrid substrate formed from the photocurable / thermosetting resin composition according to any one of claims 1 to 3. At least one of the lower clad layer, the core layer, and the upper clad layer of the optical waveguide constituting the optical / electrical hybrid substrate, and the solder resist layer or the intermediate insulating layer constituting the optical / electrical hybrid substrate, It is formed using the photocurable and thermosetting dry film which has a photosensitive layer which consists of a photocurable and thermosetting resin composition as described in any one of Claims 1 thru | or 3. Optical / electric hybrid board.