JPS645077B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a release film forming agent for silicone adhesives. Silicone adhesives exhibit or maintain their adhesive performance over a wide temperature range, and there is almost no deterioration in electrical properties even in high-temperature, high-humidity environments. , textiles, plastics, silicone rubber,
It adheres well to silicone rubber, varnished cloth, and even polytetrafluoroethylene products, and has excellent heat resistance, water resistance, and flame retardancy. Generally, for adhesives, protective paper called release paper or release paper is used for the purpose of temporarily protecting the adhesive-applied surface. That is,
This protective paper is made by providing a release film on paper or other suitable sheet-like material, and the release film is adhered by pressing the surface of the release film to the adhesive coated surface, but the adhesion is strong. It is required that it can be easily peeled off manually when used at a later date, and that it does not have an adverse effect on the adhesive layer. However, for conventional silicone adhesives, no protective paper (release paper) with a satisfactory release film with the above-mentioned performance has been developed.
Several proposals have also been accompanied by various inconveniences. For example, attempts have been made to use styrene-based resins, polyvinyl alcohol-based resins, or polyester-based resins as release film-forming agents, but release films formed with these resins have been stored in close contact with the surface coated with silicone adhesive. Under high temperature and high humidity conditions in the summer, the separation between the two may gradually become more difficult and workability may deteriorate, or in extreme cases, the two may adhere to each other, making it impossible to separate them at all. There is a problem in that the adhesive performance originally possessed by the adhesive layer gradually decreases (decrease in residual adhesive strength) during storage (this is presumed to be due to part of the release film melting into the adhesive layer). . The present invention has the advantage that even when stored for a long period of time under high temperature and high humidity, it still peels off easily compared to silicone adhesives.
Moreover, it is an object of the present invention to provide a high-quality release film forming agent that does not reduce the residual adhesive strength of the pressure-sensitive adhesive. That is, the present invention provides (a) 15 organic groups bonded to silicon atoms in one molecule.
~50 mol% is a phenyl group, and at least one of the remaining organic groups has the formula HO-R-(S) _a -R- (wherein R represents a divalent hydrocarbon group and a is 0 or 1) 100 parts by weight of a silicone-modified alkyd resin modified with an organopolysiloxane which is a hydroxy-substituted organic group, (b) 15 to 150 parts by weight of an alkanol-modified amino resin, and (c) an acidic catalyst. 1 to 20 parts by weight of a release film forming agent for silicone adhesives. The present invention will be explained in detail below. Component (a) used in the present invention is a silicone-modified alkyd resin, and in the silicone used for this modification, 15 to 50 mol% of the organic groups bonded to silicon atoms in one molecule are phenyl groups. , and at least one of the remaining organic groups is a hydroxy group-substituted organic group represented by the formula HO-R-(S) _a -R-...(1) (R and a are as described above) However, the remaining organic groups are alkyl groups such as methyl, ethyl, and octyl groups,
Any alkyl group substituted with halogen, cyano group, etc. may be used. The molecular structure of this organopolysiloxane is such that when a sheet base material coated with the release film forming agent of the present invention is applied to the adhesive surface of a so-called adhesive tape, adhesive label, or adhesive patch coated with a silicone adhesive, In addition to those with a linear structure, branched structures can be used as long as the objective of maintaining stable and easy peelability without causing blocking even when left in a fecal atmosphere at high temperature and high humidity for a long period of time is achieved. (Three-dimensional structure) may be used, but it is desirable to have relatively good compatibility with the alkyd resin. Preferred specific examples of molecular structures are as follows. In the above formula, Me represents a methyl group, Ph represents a phenyl group, m and n are positive integers, and m+n is from 30 to
It is more preferably 50 to 200 than 1000. R ₁ represents an organic group, at least one of which is represented by the above formula (1)
It is a hydroxy group-substituted organic group represented by, and the phenyl group accounts for 15 to 50 mol% of the total organic groups.
The remaining groups of R ¹ may be any of alkyl groups such as methyl, ethyl, and octyl groups, and alkyl groups substituted with halogen, cyano, and the like. The reason why in the present invention, the amount of phenyl groups in the organopolysiloxane is 15 to 50 mol%, and at least one of the remaining organic groups is a hydroxy group-substituted organic group represented by the above formula (1), This is because by using such an organopolysiloxane, it is possible to satisfy releasability, particularly stable releasability under high temperature and high humidity, and retention of residual adhesiveness. R in the hydroxy group-substituted organic group of formula (1) above is a divalent hydrocarbon group, a represents 0 or 1, and such organic groups include -CH ₂ CH ₂ -, -CH ₂ CH ₂ CH ₂
−, −(CH ₂ ) _b −S−(CH ₂ ) _c −(b is 1 or 2,
c is 2 or 3). The method for obtaining silicone-modified alkyd resin, which is component (a), using the above organopolysiloxane is mainly the usual synthesis reaction for obtaining 1-alkyd resin, that is, reaction of polyhydric alcohol with fatty acid, polybasic acid, etc. There are two methods: (2) a method in which the organopolysiloxane is simultaneously reacted as an alcohol component, and (2) a method in which a pre-synthesized general alkyd resin is reacted with the organopolysiloxane. The fatty acids used in method (1) may be any of those conventionally used in the production of alkyd resins, including saturated fatty acids such as octyl acid, lauric acid, and palmitic acid, coconut oil, and coconut oil. Examples include unsaturated oils and unsaturated oil fatty acids such as fatty acids, castor oil, castor oil fatty acids, soybean oil, soybean oil fatty acids, etc.; Preferably 20-40
is appropriate. Examples of polybasic acids include phthalic anhydride, isophthalic acid, adipic acid, maleic anhydride, fumaric acid, and trimellitic anhydride. Note that benzoic acid may also be used in combination. Examples of polyhydric alcohols include glycols such as ethylene glycol, diethylene glycol, propylene glycol, and neopentyl glycol, glycerin, trimethylolpropane, trimethylolethane, and pentaerythritol. Method (1) may be a general method of mixing components such as fatty acids, polybasic acids, polyhydric alcohols, and organopolysiloxanes in a predetermined ratio and carrying out a heating condensation reaction. Components such as basic acids and organopolysiloxane are first reacted,
A method may also be used in which the polyhydric alcohol and the polyhydric acid are then added and the condensation reaction is carried out again by heating. The reaction ratio is preferably such that the ratio of components such as fatty acids and polybasic acids to polyhydric alcohol is such that the OH/COOH equivalent is 1.0 to 1.6, preferably 1.2 to 1.4, and the organopolysiloxane is 0.1 to 0.1 to silicone-modified alkyd resin solids content
It is desirable to use it in an amount of 50% by weight, preferably 1 to 40% by weight. The reaction temperature may be determined according to the temperature at which general alkyd resins are synthesized, and 180 to 230°C is usually appropriate. Next, method (2) is carried out by reacting a synthesized general alkyd resin with organopolysiloxane.The alkyd resin used at this time has an oil length of 0 to 60, preferably 20 to 40. , acid value 1-30 preferably 5-25, hydroxyl value 50-50
Those manufactured using coconut oil or coconut oil fatty acids, soybean oil or soybean oil fatty acids, castor oil, castor oil fatty acids, and rice sugar oil fatty acids having 300 and preferably 100 to 300 are desirable. The reaction temperature for reacting organopolysiloxane with such alkyd resin is usually 60 to 200℃.
The temperature is preferably 100 to 180°C, and the progress of the reaction can be confirmed by measuring the viscosity, acid value, and hydroxyl value at any time. Therefore, the heating condensation reaction may be continued until these values reach the desired values. The amount of organopolysiloxane to be used is the same as in the case of method (1) above, based on the solid content of the silicone-modified alkyd resin finally obtained.
It is desirable that the content be 0.1 to 50% by weight, preferably 1 to 40% by weight. Note that when carrying out method (2), there is no problem in using a small amount of an amino resin or the like in combination with the alkyd resin. As the alkanol-modified amino resin which is the component (b), any commercially available ones can be used, including methoxymethylol melamine resin, butoxymethylol melamine resin, butoxymethylol urea-melamine resin, etc. Examples include condensation resin and butoxymethylolbenzoguanamine resin. Further, as the acidic catalyst which is the component (iii), any catalyst such as para-toluenesulfonic acid or hydrochloric acid which is usually used for amino alkyd resins may be used. The blending ratio of components (a), (b), and (c) is determined according to the purpose of the present invention, which is to obtain a release film that maintains stable release force against silicone adhesives and does not cause a decrease in residual adhesive strength. From this perspective, for every 100 parts by weight of component (A), 15 to 150 parts by weight of component (B), and (c)
It is desirable that the amount of the component be 1 to 20 parts by weight. Outside these ranges, the above-mentioned preferred physical properties cannot be obtained. Note that, if necessary, ordinary alkyd resins, acrylic resins, silicone-modified acrylic resins, etc., or inorganic fillers and the like may be added for the purpose of improving coating strength and heat resistance. The release film forming agent of the present invention is usually conveniently used in the form of a solvent solution, and the solvent used for this purpose is one that is reactive with the components (a) and (b). For example, benzene, toluene, xylene, methanol, ethanol, isobutanol, n-butanol,
One or a mixture of two or more of methyl ethyl ketone, acetone, tetrahydrofuran, etc. is used. The amount used is usually such that the resin solid content is in the range of 10 to 60%. The release film forming agent obtained by the above method is applied to a substrate and heated and cured at 130 to 200°C to obtain a coating with excellent releasability. The base materials used in this case include papers such as art paper and coated paper (for example, polyethylene laminated paper), plastic films such as polyethylene, polypropylene, polyvinyl alcohol, and polyester, or embossed products of these materials, and even glass cloth. Examples include glass cloth tape. The release film-forming agent of the present invention can be applied to the back side of a silicone adhesive tape in addition to the above-mentioned substrates with good results. That is, by providing the release film on the back side of the silicone adhesive tape, it becomes extremely easy to unwind the adhesive tape during use, and there is an advantage that the residual adhesive strength of the silicone adhesive tape is minimally reduced. Next, specific examples of the present invention will be given. Synthesis Example 1 [Synthesis of organopolysiloxane] Both ends of the molecular chain are blocked with dimethylvinylsiloxy groups, and the main chain contains 65 mol% of dimethylsiloxane units.
700 g of a raw material diorganopolysiloxane having a viscosity of 1900 centipoise (25°C) consisting of 35 mol% of diphenylsiloxane units, 13.3 g of 2-mercaptoethanol, 2 g of benzophenone as a photoreaction accelerator, and further as a reaction medium. Pour 700g of toluene into a flask, then insert a 100W high-pressure mercury lamp into the flask from the top.
It was irradiated for 2 hours to react. When toluene was distilled off from the reaction mixture under reduced pressure, both ends of the molecular chain of the raw material diorganopolysiloxane had the formula

705 g of a hydroxy-substituted organic group-containing diorganopolysiloxane having a viscosity of 2500 centipoise and having a main chain having a similar structure was obtained. Synthesis Example 2 [Synthesis of organopolysiloxane] Both ends of the molecular chain are blocked with dimethylvinylsiloxy groups, and the main chain contains 75 mol% of dimethylsiloxane units.
A flask was charged with 1000 g of a raw diorganopolysiloxane having a viscosity of 1000 centipoise (25°C) consisting of 25 mol% of diphenylsiloxane units, 16 g of 2-mercaptoethanol, 4 g of benzophenone, and 1000 g of toluene, and the same procedure as in the previous example was carried out. When irradiated with light and caused to react, both ends of the molecular chain of the above raw material diorganopolysiloxane changed to the formula

[Formula] is converted to a structure shown by the following formula, and the main chain has a similar structure.
1005 g of a hydroxy-substituted organic group-containing diorganopolysiloxane having a temperature of 1,000 °C was obtained. Synthesis Example 3 [Synthesis of organopolysiloxane] Both ends of the molecular chain are blocked with dimethylvinylsiloxy groups, and the main chain contains 85 mol% of dimethylsiloxane units.
A flask was charged with 800 g of a raw diorganopolysiloxane having a viscosity of 300 centipoise (25°C) consisting of 15 mol% of diphenylsiloxane units, 40 g of 2-mercaptoethanol, 5 g of benzophenone, and 800 g of toluene, and the procedure was repeated in the same manner as in the previous example. When irradiated with light and caused to react, both ends of the molecular chain of the above raw material diorganopolysiloxane changed to the formula

830 g of a hydroxy-substituted organic group-containing diorganopolysiloxane having a viscosity of 800 centipoise (25°C) and having a main chain having a similar structure was obtained. Synthesis Example 4 [Synthesis of silicone-modified alkyd resin] 109 parts of the hydroxy-substituted organic group-containing diorganopolysiloxane obtained in Synthesis Example 1 (parts by weight are shown)
(same below), 17.2 parts of coconut oil fatty acid, phthalic anhydride
Charge 249 parts and 169 parts of glycerin into a reactor,
After reacting for about 8 hours at an internal temperature of 150 to 200°C in a nitrogen atmosphere, dilute with toluene to make the solid content 60% by weight to obtain a silicone-modified alkyd resin liquid.
Obtained 1080 copies. The physical properties were as follows. Viscosity (Note) D Acid number 3.0 Hydroxyl number 65 (Note) Viscosity is the value measured by Gardner viscometer (25℃),
Same below. Synthesis Example 5 [Synthesis of silicone-modified alkyd resin] 57 parts of hydroxy-substituted organic group-containing diorganopolysiloxane obtained in Synthesis Example 2, 180 parts of coconut oil fatty acid
260 parts of phthalic anhydride and 177 parts of glycerin were charged into a reactor and reacted in the same manner as in Synthesis Example 4, followed by dilution with toluene to obtain 1040 parts of a silicone-modified alkyd resin liquid with a solid content of 60% by weight. The physical properties were as follows. Viscosity H Acid value 2.6 Hydroxyl value 73 Synthesis example 6 [Synthesis of silicone-modified alkyd resin] 32 parts of hydroxy-substituted organic group-containing diorganopolysiloxane obtained in Synthesis example 3, 200 parts of coconut oil fatty acid
290 parts of phthalic anhydride and 197 parts of glycerin were charged into a reactor and reacted in the same manner as in Synthesis Example 4, and diluted with toluene to obtain 1100 parts of a silicone-modified alkyd resin liquid with a solid content of 60% by weight. The physical properties were as follows. Viscosity K Acid value 2.8 Hydroxyl value 76 Synthesis example 7 [Synthesis of silicone-modified alkyd resin] Diorganopolysiloxane 30 obtained in Synthesis example 1
1, 224 parts of soybean oil fatty acid, 249 parts of phthalic anhydride, and 169 parts of glycerin were charged into a reactor, and Synthesis Example 4 was prepared.
React in the same manner as above and dilute with toluene to reduce the solid content to 60
1040 parts by weight of silicone-modified alkyd resin liquid was obtained. The physical properties were as follows. Viscosity I to J Acid value 3.5 Hydroxyl value 70 Synthesis example 8 [Synthesis of silicone-modified alkyd resin] 29 parts of hydroxy-substituted organic group-containing diorganopolysiloxane obtained in Synthesis example 1, 232 parts of castor oil,
215 parts of phthalic anhydride and 158 parts of trimethylolpropane were charged into a reactor and reacted in the same manner as in Synthesis Example 4, and diluted with toluene to obtain 1010 parts of a silicone-modified alkyd resin liquid with a solid content of 60% by weight. The physical properties were as follows. Viscosity Z ₃ Acid value 5.8 Hydroxyl value 71 Synthesis example 9 [Synthesis of silicone-modified alkyd resin] 28 parts of hydroxy-substituted organic group-containing diorganopolysiloxane obtained in Synthesis example 1 and coconut oil fatty acid
172 parts were charged into a reactor and reacted for 3 hours at an internal temperature of about 180°C in a nitrogen gas atmosphere (at this time, the contents showed an acid value of 224). Further, 86 parts of ethylene glycol, 94 parts of pentaerythritol, and 249 parts of phthalic anhydride were added to this, and after reacting at 150 to 200°C for 8 hours, diluted with toluene so that the solid content was 60% by weight, the silicone 960 parts of a modified alkyd resin liquid was obtained. The physical properties were as follows. Viscosity M Acid value 4.0 Hydroxyl value 60 Synthesis example 10 [Synthesis of silicone-modified alkyd resin] 35 parts of hydroxyl-substituted organic group-containing diorganopolysiloxane obtained in Synthesis example 1 and coconut oil-modified alkyd manufactured by Tokushima Seiyu Co., Ltd. Resin (Toxinol 2420−
50) in 50% xylene (oil length 20, viscosity z at 25°C by Gardner viscometer, acid value 15, hydroxyl number 95) was charged into a reactor, and heated to an internal temperature of 130 to 150°C in a nitrogen gas atmosphere. After reacting for about 5 hours, the mixture was diluted with toluene so that the solid content was 50% by weight to obtain 760 parts of a silicone-modified alkyd resin liquid. Viscosity W Acid value 12.0 Hydroxyl value 82 Example 1 Silicone-modified alkyd resin liquid obtained in Synthesis Example 4
60 parts and Tesmin 350-60 [manufactured by Tokushima Essential Oil Co., Ltd., 60% isobutanol solution of butylated urea-melamine cocondensation resin] 40 parts, dryer 50 [manufactured by Tokushima Essential Oil Co., Ltd., 50% methanol acid curing agent] Solution] 5 parts with solid content of 40%
It was diluted so that Coat this varnish on art paper to a coating film thickness of 10 μm, and dry it in a hot air dryer for 150 μm.
C. for 30 seconds to produce a release paper. The peeling force of this release paper against a silicone adhesive and the residual adhesive strength of the silicone adhesive in that case were examined by the following test method, and the results were as shown in Table 1. Test method: Apply silicone adhesive (KR-100 manufactured by Shin-Etsu Chemical Co., Ltd. with 2% benzoyl peroxide added) to a polytetrafluoroethylene tape to a film thickness of 40μ, and cure at 150℃ for 10 minutes. A silicone adhesive tape was manufactured. The coated surface of the release paper obtained above is pressed onto the adhesive surface of this adhesive tape, and peeling occurs immediately after this pressure bonding and when the pressure bonded product is left in an atmosphere of 40°C x 98% RH for a certain number of days. The force and residual adhesion were investigated. Peeling force: Measure the force required to peel off the release paper from the silicone adhesive tape using a peeling force measurement tester (measured values are expressed in g/19 mm width). Residual adhesion: After peeling off the release paper, the silicone adhesive tape was pressed onto the phenol resin plate as it was, and the force required to peel it off was measured (measured values are expressed in g/19 mm width). Example 2 Silicone-modified alkyd resin 60 obtained in Synthesis Example 5
40 parts and Tesmin 350-60 and 50 parts of the dryer
Make a varnish using 5 parts of
A release paper was produced by curing at 140°C for 60 seconds. The peel strength and residual adhesive strength were measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 3 Silicone-modified alkyd resin 60 obtained in Synthesis Example 6
40 parts and Tesmin 350-60 and 50 parts of the dryer
Make a varnish using 5 parts of
A release paper was produced by curing at 130°C for 120 seconds. The peel force and residual adhesive force were measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 4 Silicone-modified alkyd resin 60 obtained in Synthesis Example 7
40 parts and Tesmin 350-60 and 50 parts of the dryer
Use 5 parts of varnish to make a varnish, apply this to polyethylene laminate paper so that the coating film is 10μ,
A release paper was produced by curing in a hot air dryer at 150°C for 30 seconds. The peel force and residual adhesive force were measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 5 Silicone-modified alkyd resin 60 obtained in Synthesis Example 8
40 parts and Tesmin 350-60 and 50 parts of the dryer
Use 5 parts of varnish to make a varnish, apply this to polyethylene laminate paper so that the coating film is 10μ,
A release paper was produced by curing in a hot air dryer at 140°C for 60 seconds. The peel force and residual adhesive force were measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 6 Silicone-modified alkyd resin 60 obtained in Synthesis Example 9
40 parts and Tesmin 350-60, 5 parts of hair dryer 50
This was applied to polyethylene laminate paper so that the coating film was 10μ, and 130
A release paper was produced by curing for 120 seconds at ℃. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 7 Silicone-modified alkyd resin 72 obtained in Synthesis Example 10
40 parts and Tesmin 350-60, 5 parts of hair dryer 50
This was applied to polyethylene laminate paper to form a coating film of 5μ, and cured in a hot air dryer at 150°C for 30 seconds to produce release paper. The peel force and residual adhesive force were measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 8 Silicone-modified alkyd resin 60 obtained in Synthesis Example 7
48 parts of Tesmin ME50L [manufactured by Tokushima Essential Oil Co., Ltd., 50% n-butanol solution of butylated melamine resin] and 10 parts of Dryer 50 were used to make a varnish, and this was applied to a polyester film so that the coating film was 10μ. A release film was prepared by coating the film on the film and curing it in a hot air dryer at 150°C for 30 seconds. The peel force and residual adhesive force were measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 9 Silicone-modified alkyd resin 30 obtained in Synthesis Example 4
Part, Tocinol 2411-60 [manufactured by Tokushima Essential Oil Co., Ltd., coconut oil-modified alkyd resin, oil length 33, 60% xylene solution]
30 parts and Tesmin ME50L 48 parts, dryer 50 to 10
This was applied to a polyester film to a thickness of 10μ, and cured in a hot air dryer at 140°C for 60 seconds to produce a release film. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 10 Silicone-modified alkyd resin 96 obtained in Synthesis Example 10
Part, Tesmin 201-80 [manufactured by Tokushima Essential Oil Co., Ltd., 80% n-butanol solution of methylated melamine resin] was used to make a varnish using 15 parts and 10 parts of Dryer 50, and this was applied to a polyester film to a coating film of 10μ. A release film was manufactured by coating the film in such a manner that the film was cured at 130°C for 120 seconds in a hot air dryer. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 11 Silicone-modified alkyd resin 10 obtained in Synthesis Example 4
20 parts of Toxinol 2411-60, Tesroid
795 [Made by Tokushima Essential Oils Co., Ltd., acrylic resin, viscosity R, acid value
70, hydroxyl number 72, 60% xylene solution〕30
part, 48 parts of Tesmin ME50L, 10 parts of dryer 50
This was applied to glass cloth and cured in a hot air dryer at 170°C for 20 seconds to produce a release sheet. The peel strength and residual adhesive strength were measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 12 Silicone-modified alkyd resin 24 obtained in Synthesis Example 10
20 parts of Toxinol 2411-60, Tesroid
20 parts of 795, 48 parts of Tesmin ME50L, hair dryer
50 was used to make a varnish, which was applied to glass cloth and cured in a hot air dryer at 150°C for 30 seconds to produce a release sheet. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Example 13 Silicone-modified alkyd resin 40 obtained in Synthesis Example 5
40 parts of Tesroid 795, 15 parts of Tesmin 201-80 (manufactured by Tokushima Essential Oils Co., Ltd., methylated melamine resin), and 10 parts of Dryer 50 to make a varnish, coat it on glass cloth, and dry with hot air. A release sheet was produced by curing in a container at 140°C for 60 seconds. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Synthesis Example 11 [Synthesis of silicone-modified acrylic resin] 40 parts of the hydroxy-substituted organic group-containing diorganopolysiloxane obtained in Synthesis Example 1 and 304 parts of xylene were charged into a reactor, and the internal temperature was raised to 125% under nitrogen gas atmosphere.
The temperature was raised to ~130°C, and the following mixed solution was added dropwise at a constant rate over a period of 3 hours. Methacrylic acid 40 parts Methyl methacrylate 80 Butyl methacrylate 200 Styrene 40 2-hydroxyethyl acrylate 40 α,α'-azobisisobutyronitrile 11 Di-t-butyl peroxide 2 After the completion of the dropwise addition, the reaction was continued at the same temperature for 5 hours. Subsequently, 755 parts of silicone-modified acrylic resin liquid was obtained. Solid content 60.5% Viscosity N Hydroxyl value 25 Example 14 Silicone-modified alkyd resin liquid obtained in Synthesis Example 4
30 parts, 30 parts of silicone-modified acrylic resin liquid obtained in Synthesis Example 11, 40 parts of Tesmin 350-60, dryer
Use 5 parts of 50 to make a varnish, apply this to art paper to a coating thickness of 10μ, and dry in a hot air dryer.
A release sheet was produced by curing at 150°C for 30 seconds. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Comparative Example 1 Same as Example 1 except that 5 parts of Dryer 50 was mixed with 100 parts of the conventionally known stripping agent Tespeel Sp2400G [manufactured by Tokushima Essential Oils Co., Ltd., glossy amino alkyd resin] to form a varnish. A release paper was produced. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Comparative Example 2 Conventionally known stripping agent Toxinol 2400Y [manufactured by Tokushima Essential Oil Co., Ltd., coconut oil-modified alkyd resin, oil length 40%, 60
% toluene solution] A release paper was produced in the same manner as in Example 1, except that 55 parts of Desmodyur L was mixed with 100 parts of a varnish-like product. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Comparative Example 3 A polyester film without any coating treatment was prepared as a substitute for release paper. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Comparative Example 4 A polyvinyl alcohol film without any coating treatment was prepared as a substitute for release paper. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1. Comparative Example 5 A conventionally known silicone release paper (a coated paper coated with a silicone resin mainly composed of dimethylpolysiloxane) was prepared. The peeling force was measured in the same manner as in Example 1, and the results were as shown in Table 1.

【table】

Claims (1)

[Scope of Claims] 1 (a) 15 to 50 mol% of the organic groups bonded to silicon atoms in one molecule are phenyl groups, and at least one of the remaining organic groups has the formula HO-R- (S) _a Silicone-modified alkyd modified with an organopolysiloxane which is a hydroxy group-substituted organic group represented by a -R- (R in the formula represents a divalent hydrocarbon group and a is 0 or 1) A release film forming agent for a silicone adhesive, comprising: 100 parts by weight of a resin, (b) 15 to 150 parts by weight of an alkanol-modified amino resin, and (c) 1 to 20 parts by weight of an acidic catalyst.