JPH0653641A - Curable composition for thermally resistant masking tape of printed-circuit board - Google Patents

Abstract

PURPOSE:To obtain a curable composition which has a viscosity of the level capable of screen printing and has a sufficiently long pot life, by making the composition have four specific components as its main components. CONSTITUTION:A curable composition whose main components are a compounds (A) having at least one alkenyl radical in its molecule, a compound (B) having at least two hydrosilyl groups in its molecule, a hydroxylic catalyser (C), and fine silica powder (D). Altrough as the component (A) there is no particular restriction in it, a compound having ether linkages is exemplified concretely. Its molecular weight of 1000-2000 is preferred particularly. As a group of the compound (B), the hydrosilyl group, which is delivered from multivalent hydrogensiloxane including two silicon atoms, is exemplified concretely. It is preferred that the molecular weight of the part of this radical is not larger than 500. As the component (C), platinum single substance, a catalyst whose carrier carries platinum, and so forth are exemplified. As the component (D), silica hydrate and silica anhydride can be used.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a composition for heat-resistant masking tape for printed circuit boards. More specifically, an addition type curable heat-resistant masking tape for printed boards, which comprises a compound having at least one alkenyl group in the molecule, a compound having at least two hydrosilyl groups in the molecule, and a hydrosilylation catalyst as main components. Composition.

[0002]

2. Description of the Related Art Conventionally, as a heat-resistant masking tape for a printed circuit board, a composition containing a polyvinyl chloride paste as a main raw material has been used. In all of these, a plasticizer is used as a dispersant. There is. However, these compositions generally deteriorate after being immersed in a solder bath due to evaporation of a plasticizer, and the removability afterwards becomes a problem, and the properties required for the use have not been sufficiently satisfied.

The properties required for the use are as follows: 1) a viscosity that allows screen printing, 2) a sufficient pot life for securing the screen printing work time, and 3) a short curing / drying time. 4) There is no residual tack in the obtained masking tape, 5) Tack occurs in the masking tape after immersion in a solder bath,
There are no deteriorations such as melting and burning, 6) good removability (both low adhesive strength and tape strength), 7) no corrosion or contamination of the electrode surface after repeeling. To be

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a curable resin composition for a heat resistant masking tape for a printed circuit board, which satisfies all the above required characteristics.

[0005]

That is, the present invention provides a curable composition for a printed circuit board masking tape containing the following four components (A) to (D) as main components: (A) At least one in the molecule A compound having an alkenyl group, (B) a compound having at least two hydrosilyl groups in the molecule, (C) a hydrosilylation catalyst, (D)
Silica fine powder. Is the content.

The compound having at least one alkenyl group in the molecule which is the component (A) of the present invention is not particularly limited, and various compounds from low molecular weight compounds to organic polymers can be used. The alkenyl group is not particularly limited, but is of the formula (I)

[0007]

[Chemical 1]

An alkenyl group represented by the formula (wherein R ¹ is hydrogen or a methyl group) is preferable. To describe the component (A) in detail, first, the formula (II)

[0009]

[Chemical 2]

(R ¹ is hydrogen or methyl, R ² is a divalent hydrocarbon group having 1 to 20 carbon atoms and may contain at least one ether bond. R ³ is an aliphatic or aromatic group. An organic group, a is a compound having an ether bond represented by a positive integer.). In formula (II), R ² is a divalent hydrocarbon group having 1 to 20 carbon atoms, in R ² is
It may contain one or more ether bonds.
In particular,

[0011]

[Chemical 3]

And the like. Due to ease of synthesis
CH ₂ - is preferred. In the formula (II), R ³ is an aromatic or aliphatic organic group. Specifically,

[0013]

[Chemical 4]

[0014]

[Chemical 5]

[0015]

[Chemical 6]

[0016]

[Chemical 7]

[0017]

[Chemical 8]

And the like. Of these, the following are preferred.

[0019]

[Chemical 9]

[0020]

[Chemical 10]

R ³ may be an organic polymer, and various kinds can be used. First, as the polyether polymer, for example, polyoxyethylene, polyoxypropylene, polyoxytetramethylene, polyoxyethylene-polyoxypropylene copolymer and the like are preferably used. Other polymers having a main chain skeleton include condensation of dibasic acid such as adipic acid and glycol, or
Polyester polymers obtained by ring-opening polymerization of lactones, ethylene-propylene copolymers, polyisobutylene, copolymers of isobutylene and isoprene, etc., polychloroprene, polyisoprene, isoprene and butadiene, acrylonitrile, styrene and the like. Copolymer of polybutadiene, butadiene and styrene, copolymers of acrylonitrile and the like, polyisoprene, polybutadiene, isoprene or a polyolefin-based polymer obtained by hydrogenating a copolymer of butadiene and acrylonitrile, styrene and the like, ethyl Polyacrylic acid ester obtained by radical polymerization of monomers such as acrylate and butyl acrylate, acrylic acid ester such as ethyl acrylate and butyl acrylate, and vinyl acetate, acrylonitrile, methyl Methacrylate, acrylic acid ester copolymers with styrene, the graft polymer obtained by polymerizing a vinyl monomer in an organic polymer,
Polysulfide polymer, nylon 6 by ring-opening polymerization of ε-caprolactam, nylon 66 by condensation polymerization of hexamethylenediamine and adipic acid, nylon 610 by condensation polymerization of hexamethylenediamine and sebacic acid, ε
-Nylon 11, ε by polycondensation of aminoundecanoic acid
-Nylon 1 by ring-opening polymerization of amino laurolactam
2. Of the above nylons, polyamide-based polymers such as copolymerized nylon having two or more components, for example, polycarbonate-based polymers produced by condensation polymerization of bisphenol A and carbonyl chloride, diallyl phthalate-based polymers, etc. Is exemplified.

Next, the general formula (III)

[0023]

[Chemical 11]

(R ¹ is hydrogen or a methyl group, R ² is a divalent hydrocarbon group having 1 to 20 carbon atoms and may contain at least one ether bond. R ⁴ is an aliphatic or aromatic group. And an compound having an ester bond represented by a is a positive integer.). In formula (III), R ² is the same as R ² in formula (II). In addition, R ⁴ is an aliphatic monovalent to tetravalent organic group up to an aromatic group. Specifically,

[0025]

[Chemical 12]

[0026]

[Chemical 13]

[0027]

[Chemical 14]

[0028]

[Chemical 15]

And the like. Of these, the following are preferred.

[0030]

[Chemical 16]

R ⁴ may be an organic polymer and has the formula (I
All the organic polymers exemplified as the ether compound of I) can be preferably used. Next, the general formula (IV)

[0032]

[Chemical 17]

(R ¹ is hydrogen or a methyl group, R ⁵ is an aliphatic or aromatic organic group, and a is a positive integer). In formula (IV), R ⁵ represents an aliphatic or aromatic organic group, and specifically,

[0034]

[Chemical 18]

[0035]

[Chemical 19]

[0036]

[Chemical 20]

R ⁵ may be an organic polymer and has the formula (I
All the organic polymers exemplified in the explanation of I) can be preferably used. Specific examples of the component (A) include general formula (V)

[0038]

[Chemical 21]

(R ¹ is hydrogen or a methyl group, R ² is a divalent hydrocarbon group having 1 to 20 carbon atoms and may contain at least one ether bond. R ⁶ is an aliphatic or aromatic group. And a is a positive integer.) A compound having a carbonate bond. In the formula, R ² is the formula (II)
It is the same as R ² in the above. Also, as R ⁶ ,

[0040]

[Chemical formula 22]

[0041]

[Chemical formula 23]

[0042]

[Chemical formula 24]

And the like. Of these, the following are particularly preferable.

[0044]

[Chemical 25]

R ⁶ may be an organic polymer and has the formula (I
All the organic polymers exemplified in the explanation of I) can be preferably used. When an organic polymer is used as the component (A), various proposed methods can be used for introducing an alkenyl group into the polymer.
It can be roughly classified into a method introduced after polymerization and a method introduced during polymerization.

As a method of introducing an alkenyl group after the polymerization, for example, a polymer having a functional group such as a hydroxyl group or an alkoxide group at the terminal, main chain or side chain, an active group reactive with the above functional group, By reacting an organic compound having an alkenyl group, the alkenyl group can be introduced into the terminal, main chain or side chain. Examples of the organic compound having an active group and an alkenyl group reactive with the above functional group include C ₂ -C ₂₀ unsaturated compounds such as acrylic acid, methacrylic acid, vinyl acetic acid, acrylic acid chloride, and acrylic acid bromide. Fatty acids, acid halides,
Acid anhydrides, C ₃ -C ₂₀ unsaturated fatty acid-substituted carbonic acid halides such as allyl chloroformate, allyl bromoformate, allyl chloride, allyl bromide, vinyl (chloromethyl) benzene, allyl (chloromethyl) benzene, allyl (Bromomethyl) benzene, allyl (chloromethyl) ether, allyl (chloromethoxy) benzene, 1-butenyl (chloromethyl) ether, 1-hexenyl (chloromethoxy) benzene, allyloxy (chloromethyl) benzene and the like can be mentioned.

As a method of introducing an alkenyl group during polymerization, for example, in the case of producing by a radical polymerization method, a vinyl monomer having an alkenyl group with low radical reactivity in a molecule such as allyl methacrylate and allyl acrylate, allyl mercaptan, etc. An alkenyl group can be introduced into the main chain or terminal of the polymer by using the radical chain transfer agent.

The alkenyl group-containing organic polymer may be linear or branched and has a molecular weight of 500 to 50,000.
Any of the above can be preferably used, but 1000 to 200
Particularly preferred is 00. The alkenyl group may be at the molecular end or in the molecule, but when a rubber-like cured product is prepared using the composition of the present invention, the effective end chain length becomes longer at the molecular end. Therefore, it is preferable.

The organic compound having at least two hydrosilyl groups in the molecule, which is the component (B) of the present invention, is not particularly limited, but if a group containing a hydrosilyl group is specifically exemplified,

[0050]

[Chemical formula 26]

A group containing two silicon atoms such as

[0052]

[Chemical 27]

(In the formula, R is a group selected from H, OSi (CH ₃ ) ₃ and an organic group having 1 to 10 carbon atoms, and each R may be the same or different. M and n are positive. And an integer of 2 ≦ m + n ≦ 50)

[0054]

[Chemical 28]

(Where R is the same as above, m is a positive integer,
n, p, and q are 0 or a positive integer, and 1 ≦ m + n + p
+ Q ≦ 50)

[0056]

[Chemical 29]

(Where R is the same as above, m is a positive integer,
n is 0 or a positive integer, and examples thereof include a group derived from various linear, branched or cyclic polyvalent hydrogen siloxanes represented by 2 ≦ m + n ≦ 50). Among the above various hydrosilyl groups, the molecular weight of the group constituting the hydrosilyl group is preferably 500 or less from the viewpoint that the compatibility of the hydrosilyl group-containing compound of the present invention with the component (A) is less likely to occur. In consideration of the reactivity of the hydrosilyl group, the following are preferable.

[0058]

[Chemical 30]

(Where p is a positive integer, q is 0 or a positive integer, and 2≤p + q≤4).

[0060]

[Chemical 31]

When two or more hydrosilyl group-containing groups are present in the same molecule, they may be the same or different. The total number of hydrosilyl groups contained in the component (B) may be at least 2 in one molecule, but is preferably 2 to 15 and particularly preferably 3 to 12. When the compound containing a hydrosilyl group of the present invention is mixed with a compound containing an alkenyl group (component (A)) in the presence of a hydrosilylation catalyst to cure by a hydrosilylation reaction, the number of hydrosilyl groups is 2 or more. If the amount is small, curing failure often occurs. Also,
When the number of the hydrosilyl groups exceeds 15, (B)
The stability of the components becomes poor, and in addition, a large amount of hydrosilyl groups remain in the cured product even after curing, causing voids and cracks.

The hydrosilyl group-containing compound as the component (B) is not particularly limited, but various compounds ranging from low molecular weight compounds to polymers can be used. As a specific example, the formula (VI)

[0063]

[Chemical 32]

(In the formula, X is a group having at least one hydrosilyl group, and R ¹ , R ² and R ³ are the same as R ¹ , R ² and R ³ in the formula (II). A compound having an ether bond represented by the formula (VII)

[0065]

[Chemical 33]

[0066] (wherein, X is a group having at least one hydrosilyl group of ^{the, R 1, R 2, R} 4 ^{is, R 1, R 2, R} 4 and using the same, respectively, in formula (III) A compound having an ester bond represented by
Formula (VIII)

[0067]

[Chemical 34]

(In the formula, X is a group having one or more of the above hydrosilyl groups, R ¹ and R ⁵ are R ¹ in the formula (IV),
The same as R ⁵ can be used. ) A hydrocarbon-based compound represented by the formula (IX)

[0069]

[Chemical 35]

(In the formula, X is a group having at least one hydrosilyl group, and R ¹ , R ² and R ⁶ are the same as R ¹ , R ² and R ⁶ in the formula (V). The compound having a carbonate bond represented by When an organic polymer is used as the component (B), the polymer may be linear or branched, and any one having a molecular weight of 500 to 50,000 can be preferably used, but one having a molecular weight of 500 to 20,000 is particularly preferable.
The hydrosilyl group as the component (B) may be present at the molecular end or in the molecule, but when a rubber-like cured product is produced using the composition of the present invention, it is more effective at the molecular end. This is preferable because the chain length becomes long.

The method for producing the component (B) is not particularly limited, and any method may be used. For example, (i) an organic compound having a Si—Cl group in the molecule is LiAlH ₄ , N
Si—C in the compound after treatment with a reducing agent such as aBH ₄
Method for reducing group l to Si-H group, (ii) reacting an organic compound having a functional group X in the molecule with a compound having a functional group Y reactive with the functional group and a hydrosilyl group in the molecule at the same time And (iii) a method of selectively hydrosilylating a polyhydrosilane compound having at least two hydrosilyl groups with respect to an organic compound having an alkenyl group to leave the hydrosilyl group in the molecule of the compound even after the reaction. Conceivable. Of these (i
The method ii) is particularly preferable.

As the combination of the components (A) and (B), any combination can be used.
One or both of the component and the component (B) are preferably organic polymers, and among them, the component (A) is preferably a polypropylene oxide polymer. When both the component (A) and the component (B) are low molecular weight compounds, the resulting cured product has a high crosslink density and becomes brittle, which is not preferable as a curable composition for a heat-resistant masking tape for printed circuit boards.

Examples of the hydrosilylation catalyst which is the component (C) of the present invention include platinum simple substance, solid platinum supported on a carrier such as alumina, silica, carbon black, chloroplatinic acid, chloroplatinic acid and alcohol, Complexes with aldehydes, ketones, etc., platinum-olefin complexes {for example, Pt (C
_{H 2 = CH 2) 2 (} PPh 3) 2 Pt (CH 2 = C
H _{2) 2} Cl _2}; platinum - vinylsiloxane complex {for _{example, Pt n (ViMe 2 SiOSiMe 2} Vi) m, P
t [(MeViSiO) ₄ ] _m }; platinum-phosphine complex {for example, Pt (PPh ₃ ) ₄ , Pt (PB
u _{3) 4};} platinum - phosphite complex (e.g., Pt
[P (OPh ₃ ] ₄ ) (In the formula, Me represents a methyl group, Bu represents a butyl group, Vi represents a vinyl group, and Ph represents a phenyl group,
m and n represent integers), dicarbonyldichloroplatinum, and Ashby U.S. Pat.
01 and 3159662, and platinum-hydrocarbon composites, as well as Lamorea.
The platinum alcoholate catalysts described in U.S. Pat. No. 3,220,972 are also included. Additionally, the platinum chloride-olefin composites described in Modic US Pat. No. 3,516,946 are also useful in the present invention.

Examples of catalysts other than platinum compounds include RhCl (PPh ₃ ) ₃ , RhCl ₃ and RhlAl.
₂ O ₃ , RuCl ₃ , IrCl ₃ , FeCl ₃ , AlC
l ₃ , PdCl ₂ · 2H ₂ O, NiCl ₂ , TiCl ₄
Etc. These catalysts may be used alone or in combination of two or more. From the viewpoint of catalytic activity, chloroplatinic acid, platinum-olefin complex, platinum-acetylacetonate complex and platinum-vinylsiloxane complex are preferable.

The amount of catalyst is not particularly limited, but (A)
10 ^-1 to 10 ^{-8 with} respect to ¹ mol of the alkenyl group in the component
It is preferable to use it in the range of mol. Preferably 10 ^-3 to 1
It is preferably used in the range of 0 ^-6 mol. If it is less than 10 ^-8 mol, curing will not proceed sufficiently. Further, the hydrosilylation catalyst is generally expensive and corrosive, and a large amount of hydrogen gas may be generated to cause the cured product to foam.
It is better not to use more than 0 ^-1 mol.

In the present specification, since the curable composition is cured by the addition reaction of the Si-H group to the alkenyl group using the noble metal catalyst, the curing rate is very high,
It is convenient for line production. When the hydrosilyl group-containing compound which is the component (B) is produced by the above-mentioned selective hydrosilylation, since the hydrosilylation catalyst is contained in the component (B) even after the reaction, its stability is not generally good, and the long-term When left for a period of time or when moisture is mixed, conversion of Si—H groups to Si—OH groups occurs, and phenomena such as viscosity increase and gelation are observed. Therefore, it is preferable to include a storage stability improver in the component (B).
As such a compound, a compound containing an aliphatic unsaturated bond, an organic phosphorus compound, an organic sulfur compound, a nitrogen-containing compound, a tin compound, an organic peroxide and the like can be preferably used. Specifically, benzothiazole, thiazole, dimethylmalate, 2-pentenenitrile,
2,3-dichloropropene and the like are mentioned, and thiazole is particularly preferable in terms of compatibility of pot life / rapid curing property, but not limited thereto. The amount of the storage stability improver to be used can be selected almost arbitrarily as long as it is uniformly dispersed in the component (A) and the component (B).
1 mol per 1 mol of the Si-H group-containing compound of the component (B)
It is preferably used in the range of 0 ^-6 to 10 ^-1 mol. This is because if it is less than 10 ^-6 mol, the storage stability of the component (B) is not sufficiently improved, and if it exceeds 10 ^-1 mol, curing may be hindered. The storage stability improvers may be used alone or in combination of two or more.

As the fine silica powder which is the component (D) of the present invention, hydrous silica obtained by a wet production method such as hydrolysis of sodium silicate, and heat of a silicon halide such as silicon tetrachloride or an organic silicon compound can be used. Anhydrous silica obtained by a dry production method such as decomposition can be used. Examples of the hydrous silica include Nipseal VN3, Nipseal AQ, and Nipseal L manufactured by Nippon Silica Industry Co., Ltd.
P, nip seal ER, nip seal NS, nip seal NS-T, nip seal NA, nip seal L30
0, Nip seal N300A, Nip seal E, Mon
Santo Cel FRC, Santo
Cel CS, PPG Ind Hi-Sil 23
3, Hi-Sil X303, Philadelphi
a Quso F-20 manufactured by Quarts and the like. Examples of the anhydrous silica include Aerosil 130, Aerosil 200, Aerosil 200V, Aerosil 200CF, and Aerosil 30 manufactured by Nippon Aerosil Co., Ltd.
0, Aerosil 300CF, Aerosil 380, Aerosil OX50, Aerosil TT600, Aerosil MO
X80, Aerosil MOX170, Aerosil COK8
4, Aerosil R972, Aerosil R974, Aerosil R202, Aerosil R805, Aerosil R81
2, Cab-O-Sil MS-5, C from Cabot
ab-O-Sil MS-7, Cab-O-Sil H
S-5, Cab-O-Sil MS-7 etc. are mentioned.

The amount of silica fine powder added is 10 parts of component (A).
It is preferably 1 to 100 parts by weight, and 5 to 0 parts by weight.
40 parts by weight is more preferred. If the amount added is too small, sufficient strength may not be obtained. On the other hand, if the amount added is too large, the viscosity may increase so much that screen printing cannot be performed, and a good cured product may not be obtained.

The curable composition of the present invention may optionally contain
Other fillers, antioxidants, ultraviolet absorbers, pigments, surfactants, etc. may be added as appropriate, but it is desirable not to use plasticizers because they change the properties of the cured product after immersion in the solder bath. Furthermore, it is desirable not to use a silane coupling agent because it increases the adhesiveness to the printed circuit board more than necessary.

Specific examples of the other fillers include calcium carbonate, clay, talc, titanium oxide, zinc white, diatomaceous earth, barium sulfate and carbon black.

[0081]

EXAMPLES Next, the composition of the present invention will be specifically described by way of examples, but the present invention is not limited to these examples. Synthesis Example 1 According to the method disclosed in JP-A-53-134095,
A polyoxypropylene having an allyl type olefin group at the end was synthesized.

Polyoxypropylene glycol having an average molecular weight of 3000 and powdered caustic soda were stirred at 60 ° C.,
Bromochloromethane was added to carry out the reaction and increase the molecular weight. Next, add allyl chloride to 110 ° C.
The end was allyl etherified. This was treated with aluminum silicate to synthesize a purified terminal allyl etherified polyoxypropylene.

The average molecular weight of this polyether is 7960.
And 92% of the end was an olefin group from the iodine value. Viscosity by E type viscosity system is 130 poise (40 ℃)
Met. Synthesis Example 2 A 200 ml four-necked flask was equipped with a condenser tube with a three-way cock, a pressure-equalizing dropping funnel, a thermometer, a magnetic chip,
The one with the glass stopper attached was prepared. Cyclic polyhydrogen siloxane under N ₂ atmosphere

[0084]

[Chemical 36]

(LS8600, manufactured by Shin-Etsu Chemical Co., Ltd.) 1
2.03 g (50 mmol) and 20 ml of toluene were charged into the flask. 1.76 g of 1,9-decadiene
(20 mmol), chloroplatinic acid catalyst solution (H ₂ PtCl
₆ · 6H ₂ O 1g ethanol 1g, dissolved in 1,2-dimethoxyethane 9g solution) 20 [mu] l toluene 3
What was melt | dissolved in 0 ml was prepared in the dropping funnel. The flask was placed in an oil bath at 50 ° C., and the toluene solution was dropped into the flask over 2 hours under N ₂ atmosphere. When the reaction was carried out at 50 ° C for an additional 1 hour after the completion of dropping, the IR
When the spectrum was measured, the absorption of olefin near 1640 cm ^-1 had completely disappeared, so the reaction was terminated at this point. The toluene solution after the reaction was washed with a saturated aqueous solution of ammonium chloride (100 ml × 2) and exchanged water (100 ml × 1), and dried with Na ₂ SO ₄ . Na ₂ SO ₄ was removed by filtration, benzothiazole (13 μl, 0.12 mmol) was added, the volatile matter was removed by evaporation, and then degassed under reduced pressure at 80 ° C. to obtain 9.11 g of a colorless transparent liquid. It was The hydrosilyl group in the hydrocarbon compound was confirmed as a strong absorption at 2170 cm ^-1 . In addition, Si- H in 300 MHz NMR
By comparing the calculated intensity ratio with the intensity ratio (actually measured value: 0.216) of protons between the peak of Si and C— H ₃ , the compound has an average structure of the following formula [n = 1 (M
53% for W = 998) and 4 for n = 2 [MW = 1377]
7%] mixture. Based on this, the number of Si-H groups in the unit weight was calculated to be 0.769 mol.
It was / 100 g. Synthesis example 3. A 200 ml four-necked flask equipped with a stirring rod, a dropping funnel, a thermometer, a three-way cock, and a cooling tube was prepared. Then, under a nitrogen atmosphere, cyclic hydrogen polysiloxane

[0086]

[Chemical 37]

(LS8600, manufactured by Shin-Etsu Chemical Co., Ltd.) 1
2.03 g (50 mmol) and 20 ml of toluene were charged into the flask. 6.16 g (20 mmol) of bisphenol A diallyl ether synthesized in Synthesis Example 3, chloroplatinic acid catalyst solvent solution (H ₂ PtCl ₆ .6H ₂ O
1.0 g of ethanol / 1,2-dimethoxyethane (1
/ 9V / V) dissolved in 9 g) 41 μl was dissolved in 50 ml of toluene and mixed well, and then charged into a dropping funnel. The toluene solution was dropped into the flask at 70 ° C. over 1.5 hours. When the IR spectrum was taken at the time of further reaction at 80 ° C. for 5 hours, the absorption derived from the olefin at 1645 cm ⁻¹ had completely disappeared, so the reaction was terminated at this time. Dimethylacetylene dicarboxylate (34 μl, 0.24 mmo) was added to the reaction mixture.
l) was added, toluene was distilled off under reduced pressure, and
By vacuum drying for 1 hour, 12.0 g of a pale yellow viscous liquid was obtained. This viscous liquid is 300 MHz ¹ H
Identification by NMR, IR spectrum and the like revealed that the compound was a Si-H-containing ether compound having the following structural formula.

[0088]

[Chemical 38]

Synthesis Example 4. A 200-ml four-necked flask equipped with a three-way cocked cooling tube, a pressure-equalizing dropping funnel, a thermometer, a rotor and a glass stopper was prepared. Cyclic polyhydrogen siloxane under nitrogen atmosphere

[0090]

[Chemical Formula 39]

(LS8600, manufactured by Shin-Etsu Chemical Co., Ltd.) 1
2.03 g (50 mmol) and 20 ml of toluene were charged into the flask. Diethylene glycol diallyl carbonate

[0092]

[Chemical 40]

(RAV-7N, manufactured by Mitsui Petrochemical Co., Ltd.)
5.49 g (20 mmol), chloroplatinic acid catalyst solution (H
1.0 g of ₂ PtCl ₆ .6H ₂ O in ethanol / 1,
A solution prepared by dissolving 41 μl of 2-dimethoxyethane (dissolved in 9 g of 1/9 V / V) in 50 ml of toluene was placed in a dropping funnel. The flask was placed in an oil bath at 50 ° C., and the toluene solution was dropped into the flask over 1.5 hours under a nitrogen atmosphere. When the IR spectrum was measured after completion of the dropping, the absorption of olefin near 1640 cm ^-1 had completely disappeared, so stirring was stopped at this point. Dimethylacetylene dicarboxylate (34 μl, 0.24 mmol) was added to the reaction mixture, which was then evaporated to remove volatiles.
10.2 g of a slightly viscous pale yellow liquid was obtained. The hydrosilyl group of the carbonate compound has an IR spectrum of 217
Confirmed as a strong absorption at 0 cm ^-1 . Also 300 MH
By comparing the calculated intensity ratio with the proton intensity ratio (measured value 0.181) between the Si— H peak and Si—C H _{3 in} z NMR, the compound averaged to have the structure of the following formula: Found to have. Based on this, S in unit weight
When the number of i-H groups was calculated, it was 0.47 mol / 100 g.

[0094]

[Chemical 41]

Synthesis Example 5. A 1-liter four-necked flask equipped with a stirring rod, a dropping funnel, a thermometer, a three-way cock, and a cooling tube was prepared. Next, under a nitrogen atmosphere, cyclic polysiloxane

[0096]

[Chemical 42]

(LS8600, manufactured by Shin-Etsu Chemical Co., Ltd.) 4
1.7 g (0.173 mol) was charged into the flask. Polypropylene oxide having 92% of the molecular ends synthesized in Synthesis Example 1 is an allyl group, 300 g (allyl group mole number 0.069 mol), toluene 230 ml, and chloroplatinic acid catalyst solvent (H ₂ PtCl ₆ .6H ₂ O 1. 0 g
Ethanol / 1,2-dimethoxyethane (1/9 V
/ V) dissolved in 9G) 83 μl of a toluene solution was charged to the dropping funnel. The flask was heated to 70 ° C., and the toluene solution was added dropwise at a rate of about 2 ml per minute over 5 hours. Thereafter, the reaction temperature was raised to 80 ° C., and when the mixture was stirred for about 6 hours, the residual allyl group in the reaction solution was removed by I
When quantified by R spectrum analysis method, 1645c
It was confirmed that the carbon-carbon double bond of m ^-1 had disappeared. After adding dimethyl acetylenedicarboxylate (118 μl, 0.83 mmol) to the reaction mixture,
Vacuum degassing was performed at 80 ° C. for 3 hours to remove toluene and unreacted excess cyclic polysiloxane in the reaction system.
Polypropylene oxide having hydrosilyl group About 31
5 g was obtained as a pale yellow, viscous liquid. The viscosity by an E-type viscometer was 310 poise (40 ° C.). The hydrosilyl group in the polypropylene oxide was confirmed as a strong absorption at 2150 cm ^{-1 in} the IR spectrum. Three
Analyzing the NMR spectrum of 00MHz, Si-C H ₃
And Si-C H ₂ -peak intensity and Si- H
By comparing the intensities of the peaks, it was found that an average of 1.31 hydrosilyl groups reacted per molecule of the cyclic polysiloxane. That is, the polymer has a partly increased molecular weight due to the cyclic hydrogen polysiloxane.
A polypropylene oxide having a molecular end represented by the following formula.

[0098]

[Chemical 43]

Examples 1 to 12 Organic polymer obtained in Synthesis Example 1, Si-H group-containing compound obtained in Synthesis Example 2, 3, 4, or 5, fine silica powder, hindered phenolic antioxidant (Irganox 1010 manufactured by Ciba Geigy), and a chloroplatinic acid catalyst solution (H ₂
1.0 g of PtCl ₆ .6H ₂ O dissolved in 99 g of ethanol / 1,2-dimethoxyethane (1/9 V / V) was weighed as shown in Table 1, thoroughly mixed, and then degassed under reduced pressure. . The thickness of the obtained curable composition after drying is 400 μm.
Screen printed on the printed circuit board so that
A masking tape was prepared by curing at 0 ° C. for 5 minutes.

[0100] Separately, the curable composition obtained under the same conditions was punched into a dumbbell and a tensile test was conducted. The results are shown in Table 2. The tack of the obtained masking tape is examined by touching the finger, and after dipping in a solder bath (260 ° C) for 10 seconds, the tack is examined again by touching the finger, and the masking tape portion is peeled at a rate of 200 mm / min at 180 ° C. Peeling was performed, and the peeling conditions (tape break, adhesive residue, contamination of substrate and copper electrode) were examined, and the results are shown in Table 2.

[0101]

[Table 1]

[0102]

[Table 2]

[0103]

As is clear from the results of Tables 1 and 2, the curable composition of the present invention has a screen-printable viscosity and a sufficient pot life, and has a short curing and drying time.
The obtained masking tape has no residual tack, has sufficient strength, does not deteriorate after immersion in a solder bath, and is suitable for a heat-resistant masking tape for a printed circuit board.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location C08L 83/05 LRM 8319-4J 101/02 LTA 7242-4J (72) Inventor Kazuya Yonezawa Kobe, Hyogo Prefecture 5-12-11 Azalea Hill, Tarumi-ku, Yokohama

Claims (6)

[Claims] 1. A curable composition for a printed circuit board masking tape, which comprises the following four components (A) to (D) as main components; (A) a compound having at least one alkenyl group in the molecule, (B) A compound having at least two hydrosilyl groups in the molecule, (C) hydrosilylation catalyst, (D) fine silica powder. 2. The composition according to claim 1, further comprising a storage stability improver. 3. A compound having at least one alkenyl group in the molecule has a number average molecular weight of 500 to 50,000.
The composition according to claim 1, which is an oligomer composed of the polyether main chain. 4. The composition according to claim 1, wherein the content of the plasticizer is 0. 5. The composition according to claim 1, wherein the fine silica powder is hydrous silica. 6. The composition according to claim 1, wherein the fine silica powder is anhydrous silica.