JPS6118924B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a photocurable organopolysiloxane composition that cures in an extremely short time when exposed to light and has excellent moisture-resistant adhesive properties. Various organopolysiloxanes that can be cured by light (ultraviolet) irradiation have been known, but all of them have problems with moisture resistance and adhesion after photocuring, and are difficult to adhere to substrates. It had its drawbacks. For example, if a metal or ceramic material that has been applied to the surface of a substrate and photocured is immersed in boiling water for about an hour, its adhesion to the substrate will be significantly weakened.
There was a problem in that when adhesive tape was applied and then removed, most of the paint film was peeled off from the substrate. The present invention aims to provide a novel organopolysiloxane composition that improves such conventional drawbacks, and which has (a) an average compositional formula of [In the formula, R ¹ is a divalent hydrocarbon group, R ² is a substituted or unsubstituted monovalent hydrocarbon group, and at least one of X is a (Here, R ³ is a hydrogen atom or a carbon atom number of 1 to 4
^R4 represents a divalent hydrocarbon group), and the remainder represents a hydrogen atom. n is 0 or a positive integer of 4 or less, 0<a≦3, 0≦b<3, but 0<a+
b≦3. ] 100 parts by weight of an acryloyloxy group-containing organopolysiloxane, (b) General formula R ⁵ _c SiZ _4-c ... () (wherein R ² is a monovalent hydrocarbon group containing at least one epoxy group , Z represents a halogen atom or a hydrolyzable group, and c is 1, 2 or 3) or a partially hydrolyzed condensate thereof
This relates to a composition comprising 0.01 to 50 parts by weight of (c) a photosensitizer. The composition of the present invention cures in a very short time, for example, 30 seconds, when irradiated with light, and exhibits remarkable adhesion to alumina substrates and various other metals such as copper, iron, zinc, tin, silver, and palladium. It also has the characteristics of excellent moisture-resistant adhesion. To explain this, the acryloyloxy group-containing organopolysiloxane used in the present invention is
It is represented by the above average compositional formula (), in which:
Examples of the divalent hydrocarbon group represented by R ¹ include a methylene group, ethylene group, and propylene group, and examples of the substituted or unsubstituted monovalent hydrocarbon group represented by R ² include a methyl group, an ethyl group, Examples include a propyl group, a butyl group, a vinyl group, an allyl group, a phenyl group, or a group in which some or all of the hydrogen atoms of these hydrocarbon groups are substituted with a halogen atom or the like. X is a hydrogen atom or the above formula ()
In the formula, R ³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group. and also
R ⁴ represents a divalent hydrocarbon group, which includes the above R ¹
An example similar to this is given. In the average composition formula (), n is 0 or a positive integer of 4 or less, and a and b are each 0<a≦
3, 0≦b<3, and 0<a+b≦3. In the present invention, at least one of X in the average compositional formula () is a monovalent group represented by the formula (), and the organopolysiloxane composition according to the present invention is cured by light irradiation. This is necessary to ensure that this is carried out reliably. In the present invention, the acryloyloxy group-containing organopolysiloxane represented by the above average composition formula () in which R ¹ is a propylene group, R ² is a methyl group, a vinyl group, or a phenyl group, X is a formula Particularly preferred are compounds which are monovalent groups represented by: The acryloyloxy group-containing organopolysiloxane represented by the average composition formula () is
It can be produced by two methods, the first of which is the average composition formula (In the formula, R ¹ represents a divalent hydrocarbon group, R ² represents a substituted or unsubstituted monovalent hydrocarbon group, n is 0 or a positive integer of 4 or less, 0<a≦
3, 0≦b<3, but 0<a+b≦3)
Organopolysiloxane and general formula shown by (In the formula, R ³ is a hydrogen atom or has 1 to 1 carbon atoms.
The alkyl group of 4 can be obtained by addition reaction with an acrylic acid derivative represented by (R ⁴ represents a divalent hydrocarbon group, respectively), and the second method is a method in which silicon atoms are added to each molecule in one molecule. Organopolysiloxane with bonded hydroxyl or alkoxy groups and general formula [In the formula, R ¹ is a divalent hydrocarbon group, R ² is a substituted or unsubstituted monovalent hydrocarbon group, R ⁶ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Both are expressions (Here, R ³ is a hydrogen atom or a carbon atom number of 1 to
4 represents an alkyl group, R ⁴ represents a divalent hydrocarbon group), the remainder represents a hydrogen atom, n is 0 or a positive integer of 4 or less, d is 0
or a positive integer of 2 or less, f is a positive integer of 3 or less, where d+f is a positive integer of 3 or less]. Next, the epoxy group-containing silane as component (b) used in the present invention is represented by the above general formula (), where R ⁵ is a monovalent hydrocarbon containing at least one epoxy group. A group, which includes either a linear or alicyclic group having an epoxy group. Z in the formula is a halogen atom or a hydrolyzable group, and examples of the hydrolyzable group include an alkoxy group, an acyloxy group, an amino group, an ayodo group, an aminooxy group, a ketoxime group, and a vinyloxy group. This epoxy group-containing silane has various combinations (various combinations of R ⁵ and Z) in which c in the formula is 1, 2, or 3, and any of them can be used, but in the present invention, Partial hydrolytic condensation of one type or a mixture of two or more of these various epoxy group-containing silanes can also be effectively used. Note that among the epoxy group-containing silanes consisting of various combinations of ^R5 and Z, γ-glycidyloxypropyltrimethoxysilane, β-(3,
It is desirable to use 4-epoxycyclohexyl)ethyltrimethoxysilane or a partially hydrolyzed condensate thereof (degree of polymerization of approximately 10 or less). The blending ratio of component (b) is required to be 0.01 to 50 parts by weight per 100 parts by weight of component (a). This is because if the amount is as small as 0.01 part by weight or less, no moisture-resistant adhesive effect will be obtained, while if it is more than 50% by weight, the relative amount of photosensitive groups will decrease and the photocurability will be poor. Photosensitizers as the component (c) include benzoin and its derivatives, benzoin ethers such as benzoin methyl ether, benzyl and its derivatives, aryl diazonium salts, anthraquinone and its derivatives,
Examples of these photosensitizers include acetophenone and its derivatives, sulfur compounds such as diphenyl disulfide, and benzophenone and its derivatives.
Species or mixtures of two or more species may be used. These photosensitizers are used in amounts of 0.01 to 30 parts by weight per 100 parts by weight of component (a).
It is effective to use within the range of parts by weight.
If the amount is less than 0.01 part by weight, the photocuring speed of the photopolymerizable resin composition is slow and a cured coating film with excellent electrical and mechanical properties cannot be obtained from the cured resin, which is undesirable. If the amount is larger than this, a cured resin product with a high molecular weight cannot be obtained, and the electrical properties are significantly deteriorated, which is undesirable, and in either case, it is difficult to put it into practical use. The amount of photosensitizer added is preferably 0.1 to 5 parts by weight. The resin composition according to the present invention is as described above (a).
It can be obtained by mixing components (b) and (c), but in this case, component (a) is dissolved in advance in an aromatic hydrocarbon such as toluene or xylene, or even in a ketone or alcohol-based solvent, and then the ( A method may be adopted in which the solvent is removed after uniformly mixing component (b) and component (c). In addition, after mixing component (a) and component (b) with an organic solvent and heat-treating this mixture (this heat treatment seems to partially progress the addition reaction between the two), component (c) is mixed. A method of uniformly mixing and removing the solvent may also be used. When applying or impregnating a target substrate with the composition of the present invention, it may be advantageous to use a viscosity modifier. at least one

It has a group represented by the following formula (R ⁷ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms), and has a boiling point of 100°C at normal pressure.
As mentioned above, addition polymerizable monomers are preferable,
These include styrene, styrene derivatives such as vinyltoluene, acrylic acid compounds such as acrylic acid and butyl acrylate, methacrylic acid compounds such as methacrylic acid and ethyl methacrylate, and 1,6-
Polyfunctional acrylic ester compounds or polyfunctional methacrylic ester compounds having two or more unsaturated groups such as hexanediol diacrylate, ethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, 2-
Hydroxyethyl methacrylate, 2-hydroxy methacrylate, Aronix M-5700, M-
Examples include polyester oligomers with acryloyloxy or methacryloyloxy groups such as 6300, M-7100+M-8060 (manufactured by Toagosei Kagaku Kogyo Co., Ltd., trade name), and other polyfunctional vinyl monomers such as divinylbenzene and diallyl phthalate. , one or a mixture of two or more of these monomers may be used. It is effective to use these monomers in an amount of 500 parts by weight or less based on 100 parts by weight of the composition of the present invention. If more than 500 parts by weight is used, the electrical properties, mechanical properties and heat resistance of the cured film will deteriorate, which is undesirable and difficult to put to practical use in any case. It should be noted that fillers, thixotropic agents, pigments (coloring agents), antioxidants, adhesion promoters, surface hardening accelerators, radical polymerization initiators, etc. may be added to the composition of the present invention as necessary. do not have. As the filler, aluminum oxide, silicon dioxide, calcium carbonate, titanium dioxide, barium sulfate, mica powder, etc. can be used, and as the thixotropic agent, fine silicon dioxide powder having a specific surface area of 100 to 450 m ² /g is preferable. Further, as the coloring agent, ordinary pigments and dyes such as phthalocyanine green and phthalocyanine blue can be used. Usual thermal polymerization inhibitors such as hydroquinone, hydroquinone methyl ether, catechol, and 2,6-di-t-butyl-4-methylphenol are effective as antioxidants, and γ-methacrylosiloxane is effective as an adhesive agent. Propyltrimethoxysilane, Vinyltris(β-methoxyethoxy)silane, N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β(aminoethyl)-γ-
Silane coupling agents such as aminopropylmethyldimethoxysilane are good, especially N-β
(Aminoethyl)-γ-aminopropyltrimethoxysilane and γ-aminopropyltriethoxysilane are preferred. As a surface hardening accelerator, cobalt naphthenate,
Organic acid metal salts such as manganese octylate are preferable. The cured resin material obtained by this method has excellent electrical properties, especially frequency characteristics of dielectric constant and dielectric loss tangent, and temperature characteristics. It is also heat resistant, can be used continuously at temperatures of 150°C or higher, and is moisture resistant. Good sex. The resin composition according to the present invention does not necessarily include a filler, but when it is blended, the viscosity of the resin composition varies depending on the application method such as screen printing or spraying, but at room temperature the viscosity is 100~ Preferably 250,000 centipoise. The composition of the present invention is cured by light irradiation, and examples of the light source that supplies this light include high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, carbon arc lamps, and xenon lamps. Hereinafter, reference examples and examples will be given and explained. Reference example 1 Hydroxyl group-containing organopolysiloxane (hydroxyl group content 5% by weight, methyl group/phenyl group = 1.6, 25
860 g of a xylene solution containing 70% N-(2-aminoethyl)-
150g of 3-aminopropyltrimethoxysilane,
After heating a mixture of 870 g of xylene and 0.5 g of potassium hydroxide as an equilibration catalyst under reflux at 90°C for 3 hours, the methanol produced here
45 g was removed to obtain an amino group-containing organopolysiloxane. Next, 260 g of glycidyl methacrylate was added to the amino group-containing organopolysiloxane obtained above.
was added and reacted at 70°C for 3 hours to obtain an acryloyloxy group-containing organopolysiloxane composition solution by addition reaction between the amino group and the epoxy group. Next, 2 g of trimethylchlorosilane, 2 g of xylene, and 15 g of potassium acetate were added for the purpose of neutralization, and after stirring at 60°C for 1 hour, 30 g of diatomaceous earth was added as a filter aid and filtered under normal pressure. When chlorosilane and other unreacted substances were removed, a pale yellow, transparent reaction product with a viscosity of 126,000 centipoise was obtained. As a result of infrared absorption spectrum analysis, this product was confirmed to be an organopolysiloxane containing an acryloyloxy group. Reference Example 2 Hydroxyl group-containing organopolysiloxane (hydroxyl group content: 5 parts by weight, methyl group/phenyl group = 1.6)
A mixture consisting of 860 g of a 70% xylene solution, 150 g of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 870 g of xylene, and 0.2 g of potassium hydroxide as an equilibration catalyst was heated under reflux at 88° C. for 8 hours. Thereafter, the temperature was raised to 126° C. over a period of 1 hour, and 45 g of generated methanol was removed to obtain an amino group-containing organopolysiloxane. Next, glycidyl methacrylate 200 was added to the amino group-containing organopolysiloxane thus obtained.
A mixture of g and 25 g of a partially hydrolyzed condensate of γ-glycidoxypropyltrimethoxysilane was added dropwise over 1 hour while being maintained at 60°C, and then aged for 3 hours to form an amino group and an epoxy group. Through the reaction, an acryloyloxy group-containing organopolysiloxane composition solution was obtained. Next, for the purpose of neutralization, 2 g of trimethylchlorosilane, 4 g of xylene, and 15 g of potassium acetate were added, stirred at 50°C for 2 hours, and left at room temperature for 3 hours to completely neutralize the sediment. 30g of diatomaceous earth was added, filtered under normal pressure, and further distilled for 6 hours at 60°C under a reduced pressure of 2mmHg to remove xylene, trimethylchlorosilane, and other low-boiling unreacted substances.As a result, the product was pale yellow, transparent, and viscous. A reaction product of 75,000 centipoise was obtained. This is the result of infrared absorption spectrum analysis.
It was confirmed that it was an organopolysiloxane containing an acryloyloxy group and an epoxy group. Example 1 100 parts by weight of the acryloyloxy group-containing organopolysiloxane obtained in Reference Example 1 above, 40 parts by weight of 2-hydroxyethyl methacrylate, 0.5 parts by weight of 4-methoxybenzophenone, γ-glycidoxypropyltrimethoxysilane 3 parts by weight, KBM
-603 (N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, trade name manufactured by Shin-Etsu Chemical Co., Ltd.)
5 parts by weight were mixed uniformly to form a resin composition, which was applied onto an alumina substrate and irradiated with a high-pressure mercury lamp (3.2 KW) from a distance of 12 cm for about 1 minute to form a cured coating film with a thickness of about 100 μm. Obtained. The alumina substrate having this coating film was immersed in boiling water for 1 hour, and after drying, the coating film was subjected to various tests, and the results were as follows. (a) Paint film hardness (pencil hardness): 3H (b) Vertical test: 100/100 (c) Cross cut peeling test: Make a cross cut at an angle of about 30° with a razor blade and check for peeling of the adhesive tape. However, the adhesive remained completely adhered and no peeling was observed. (d) Solvent resistance: No peeling occurred when immersed in a mixture of 1,1,1-trichloroethane and n-butylcarbitol (1:1) at room temperature for 10 minutes, and there was no Even though sonic immersion was performed for 10 minutes, there was no change and the bond remained completely adhered. (e) Heat resistance: No change occurred in the coating film even though it was immersed in solder solution at 230°C for 2 minutes. (f) Dielectric constant (frequency 0.1~10KHz, temperature 20~150
℃): 2.8~3.8 (g) Dielectric loss tangent (frequency 0.1~10KHz, temperature 20~150
°C): 0.7 to 1.9% (h) Heat resistance deterioration test: Although heated at 200 °C for 1000 hours, there was almost no change in the physical properties such as dielectric constant and dielectric loss tangent. Example 2 100 parts by weight of the acryloyloxy group-containing organopolysiloxane obtained in Reference Example 2 above, 20 parts by weight of ethylene glycol dimethacrylate, 20 parts by weight of Aronix M-5700 (trade name manufactured by Toagosei Chemical Industry Co., Ltd.), 0.5 parts by weight of benzophenone. A resin composition consisting of 30% was applied to a substrate, and then irradiated with a metal halide lamp (3KW) from a distance of 15cm for about 20 seconds to obtain a cured coating. 1 of this stuff in boiling water
When the coating was immersed for a period of time, dried, and then peeled off using adhesive tape, the coating did not peel off or peel off, and no abnormalities in appearance were observed. Example 3 100 parts by weight of the acryloyloxy group-containing organopolysiloxane obtained in Reference Example 2 above, 30 parts by weight of 2-hydroxypropyl methacrylate, Aronix M-6300 (trade name manufactured by Toagosei Chemical Industry Co., Ltd.) 30
Parts by weight, 5 parts by weight of γ-glycidoxypropyltrimethoxysilane, KBE-903 (γ-aminopropyltriethoxysilane, trade name manufactured by Shin-Etsu Chemical Co., Ltd.)
5 parts by weight, 0.5 parts by weight of 4-methoxybenzophenone, 0.5 parts by weight of 2-methylanthraquinone, 50 parts by weight of α-alumina powder with an average particle size of 1 μm, and 7 parts by weight of silicon dioxide fine powder with a specific surface area of 380 m ² /g. , 2 parts by weight of phthalocyanine green, and 3 parts by weight of γ-methacryloxypropyltrimethoxysilane, and the resin composition made uniform by three-roll kneading is printed on a substrate by an ordinary screen printing machine to about 20 μm.
Printed to m thickness, metal halide lamp (3KW)
was irradiated for about 20 seconds from a distance of 10 cm to obtain a smooth cured coating. This cured coating has no pinholes and maintains good adhesion to the board even after solder reflow (230°C/20 seconds).
The cured coating film has a pencil hardness of 5H or higher. Also, 1,1,1- used for cleaning solder flux.
No change was observed even after 30 minutes of immersion in trichlorethylene at room temperature or 5 minutes of ultrasonic immersion, indicating excellent solvent resistance. Further, a peel test using an adhesive tape was performed after immersion in boiling water for 1 hour, but the coating remained in close contact with the substrate. Example 4 Pd-Ag based electrode material (manufactured by Electro Science Laboratories, trade name: ESL9630) was screen printed on one side of a 96% alumina substrate with dimensions of 20 mm x 20 mm x 1 mm, and baked at 950°C for 10 minutes to remove the lower part. Create an electrode (film thickness 10 μm) and deposit BaTiO ₃ on top of it.
A dielectric material (manufactured by Dupont, trade name: Dp8289) containing Pd-Ag as the main component was printed and dried at 130°C for 20 minutes to create a dielectric material (film thickness 50 μm). The electrode material was printed and baked at 950°C for 10 minutes to create an upper electrode (film thickness: 10 μm), and a thick film capacitor was obtained. The resin composition obtained in Example 2 was applied with a brush to the above thick film capacitor, and a high-pressure mercury lamp (3.2KW) was applied.
was irradiated for 60 seconds from a distance of 15 cm to cure it. This resin-coated thick film capacitor was subjected to high-humidity load tests (DC75V applied in a 150℃ atmosphere) and constant humidity load tests (DC75V applied in a 60℃/95%RH atmosphere).
There was no drop in dielectric breakdown voltage even after 1500 hours of
A resin-coated thick film capacitor with excellent heat resistance and moisture-resistant adhesion was obtained. As described above, the resin composition according to the present invention cures in a short time at room temperature, has a dielectric constant and a dielectric loss tangent that do not vary depending on frequency and temperature, has extremely excellent heat resistance and adhesive properties, and has a cured coating. There are no pinholes in the film, so it has good moisture resistance.

Claims (1)

[Claims] 1 (a) Average compositional formula [In the formula, R ¹ is a divalent hydrocarbon group, R ² is a substituted or unsubstituted monovalent hydrocarbon group, and at least one of X is a (Here, R ³ is a hydrogen atom or 1 carbon atom
4 represents an alkyl group, R ⁴ represents a divalent hydrocarbon group), and the remainder represents a hydrogen atom. n is 0 or a positive integer of 4 or less, 0<a≦3, 0≦b<3, but 0<
a+b≦3. ] 100 parts by weight of an acryloyloxy group-containing organopolysiloxane, (b) General formula R ⁵ _c SiZ _4-c (wherein R ² is a monovalent hydrocarbon group containing at least one epoxy group, Z is Each represents a halogen atom or a hydrolyzable group, and c is 1, 2 or 3.) Epoxy group-containing silane or its partially hydrolyzed condensate
A photocurable organopolysiloxane composition comprising 0.01 to 50 parts by weight of (iii) a photosensitizer.