JP2002338890A - Primer composition for silicone adhesive - Google Patents

Abstract

(A) A diorganopolysiloxane having an alkenyl group at both ends of a molecular chain and having an average degree of polymerization of 500 to 2,000, wherein the number of moles of the contained alkenyl group is 0.001 to 0.005 mol of diorganopolysiloxane per 100 g of the diorganopolysiloxane, (B) an organohydrogenpolysiloxane having at least two hydrogen atoms directly bonded to silicon atoms in one molecule, (C) A primer composition for a silicone pressure-sensitive adhesive, comprising a platinum-based curing catalyst and (D) a reaction control agent. Effect: The primer composition of the present invention satisfactorily adheres a silicone pressure-sensitive adhesive to the surface of a plastic film substrate and provides a pressure-sensitive adhesive composition having excellent adhesion durability, and can be used in a wide range of fields. it can.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a primer composition for a silicone pressure-sensitive adhesive, and more particularly, to a pressure-sensitive adhesive tape having a silicone pressure-sensitive adhesive layer provided on a plastic film, which is excellent in the plastic film and the silicone pressure-sensitive adhesive layer. The present invention relates to a primer composition suitable for being closely adhered to a primer composition.

[0002]

2. Description of the Related Art
As the heat-resistant adhesive tape, a tape formed by applying and laminating a silicone adhesive having excellent heat resistance on a plastic film base material such as a polyester film or a polyimide film is used. Such adhesive tapes are usually
Although it is wound up in a roll, if it is rewound strongly at the time of use, the silicone pressure-sensitive adhesive layer may peel off from the substrate. Further, when the pressure-sensitive adhesive tape is cut, only the base material is torn, and the silicone pressure-sensitive adhesive layer may be stretched so as to draw a thread without being cut, or the silicone pressure-sensitive adhesive layer may rise from the base material.

[0003] As described above, there is a case where there is a problem in using as a pressure-sensitive adhesive tape, and it has been difficult to say that the adhesion between the silicone pressure-sensitive adhesive and the plastic film substrate is sufficient. Therefore, generally, after applying a carbon functional silane-based primer composition as an adhesion improver,
A method of treating a silicone adhesive to improve the adhesion between a film substrate and the silicone adhesive has been adopted. However, the adhesion was not satisfactory.

On the other hand, many primer compositions using an organopolysiloxane for adhering a silicone adhesive to a plastic film have been proposed. For example, in Japanese Patent Publication No. 54-44017, a primer composition comprising diorganopolysiloxane, organohydrogenpolysiloxane and organic carboxylic acid tin salt containing hydroxyl groups at both molecular chain terminals is disclosed in Japanese Patent Publication No. 6-39584. A primer composition comprising a diorganopolysiloxane containing hydroxyl groups at both molecular terminals, an organohydrogenpolysiloxane, a hydrolyzable silyl group-containing vinyl and / or acrylic copolymer, and a tin salt of an organic carboxylic acid has been proposed. ing.

However, there is a case where satisfactory adhesion cannot be obtained by using any of the primer compositions. For example, the curing of an addition-curable silicone pressure-sensitive adhesive that has come to be used in recent years is performed at a lower temperature, so that the adhesion between the pressure-sensitive adhesive and the substrate is more difficult, and a heat-resistant polyimide film or the like is not used. It is difficult to adhere as a substrate. Therefore, development of a primer composition having better adhesion is desired.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a silicone adhesive primer composition having excellent adhesion.

[0007]

Means for Solving the Problems and Embodiments of the Invention The present inventors have conducted intensive studies to achieve the above object, and as a result, have found that alkenyl group-containing organopolysiloxane, organohydrogenpolysiloxane, platinum-based curing In the primer composition containing a catalyst and a reaction control agent, the alkenyl group-containing organopolysiloxane has an average degree of polymerization of alkenyl groups at both molecular chain terminals of 500.
A diorganopolysiloxane having an alkenyl group content of 0.001 to 0.005 per 100 g of the diorganopolysiloxane.
By using a diorganopolysiloxane that is a mole, when various plastic film substrates are treated with this primer composition, the plastic film substrate, especially a substrate that is considered to be difficult to adhere to, such as a polyimide film, The present inventors have also found that a silicone adhesive, particularly an addition-curable silicone adhesive, can be provided with strong adhesiveness and a good heat-resistant adhesive tape can be obtained, and the present invention has been accomplished.

Accordingly, the present invention relates to (A) an alkenyl group at both ends of a molecular chain having an average degree of polymerization of 500 to 2,000.
Wherein the number of moles of the alkenyl group contained is 0.001 to 0.005 mol per 100 g of the diorganopolysiloxane, (B) a silicon atom in one molecule. An organohydrogenpolysiloxane having at least two hydrogen atoms directly linked to (C) a platinum-based curing catalyst,
(D) A primer composition for a silicone pressure-sensitive adhesive, comprising a reaction control agent. In this case, more preferably, (E) an organopolysiloxane having at least one each of an epoxy group-containing organic group, a hydrogen atom, and an alkoxysilyl group-containing alkyl group directly bonded to a silicon atom in one molecule, and / or ( F) One or more additives selected from fatty acids, acid anhydrides obtained by molecular condensation thereof, and intramolecular acid anhydrides can be blended.

Hereinafter, the present invention will be described in more detail.
(A) of the primer composition for a silicone pressure-sensitive adhesive of the present invention
The component diorganopolysiloxane has alkenyl groups at both molecular chain terminals, has an average degree of polymerization of 500 to 2,000, and has a mole number of alkenyl groups of 0.1 to 100 g per 100 g of the diorganopolysiloxane. 001-0.
005 mol of a diorganopolysiloxane represented by the following general formula (1) is preferably used.

[0010]

Embedded image (Wherein, R ¹ is an alkenyl group, R ² is a substituted or unsubstituted monovalent hydrocarbon group, a is an integer of 1 to 3, n is 500 to
2,000. )

Where R¹Preferably has 2 to 8 carbon atoms
Alkenyl group, specifically, vinyl group, allyl group,
Butenyl group and the like, and preferably a vinyl group.
You. R ^TwoIs a substituted or unsubstituted monovalent hydrocarbon group.
Monovalent hydrocarbon groups having 1 to 16 carbon atoms,
Preferably have 1 to 8 carbon atoms, methyl group, ethyl group
Groups, propyl, butyl, octyl and other alkyl
Group, cycloalkyl group such as cyclohexyl group, vinyl
Groups, alkenyl groups such as allyl group, phenyl group, tolyl group
Aryl such as aryl group, benzyl group, phenethyl group
And a part of these hydrogen atoms or
Is chloro substituted entirely with halogen atoms, cyano groups, etc.
Haloalkyl such as propyl group and trifluoropropyl group
Group, but particularly industrially, a methyl group or
A phenyl group is preferred.

The diorganopolysiloxane of the general formula (1) having alkenyl groups at both molecular chain terminals has an average degree of polymerization of 500 to 2,000, and the number of moles of the alkenyl group contained per 100 g of the substance. 0.001-0.
005 mol. Furthermore, the average degree of polymerization is from 1,000 to
More preferably, 2,000 and the number of moles of the alkenyl group contained is 0.001 to 0.0025 mol per 100 g of the substance. If the average degree of polymerization is less than 500, it tends to fall off from the film surface after curing, and the effect as a primer cannot be sufficiently obtained. When the average degree of polymerization is 500 or more, a primer effect can be obtained without falling off, and a primer composition having an average degree of polymerization of 1,000 to 2,000 and particularly excellent adhesion can be obtained. When the average degree of polymerization exceeds 2,000, the adhesiveness between the pressure-sensitive adhesive and the substrate becomes poor. Further, the number of moles of the contained alkenyl group is 0.0% per 100 g of the substance.
If it is less than 01 mol, the primer will not be cured, and if it exceeds 0.005 mol, the primer effect will be small.

The organohydrogenpolysiloxane of the component (B) functions as a crosslinking agent for the component (A), and has a hydrogen atom (Si) directly bonded to a silicon atom.
H group) is cured by a hydrosilylation reaction with the alkenyl group in the component (A). The component (B) is not particularly limited as long as it contains at least two hydrogen atoms directly connected to a silicon atom in one molecule. For example, the following general formula (2)
To (4).

[0014]

Embedded image (Wherein R ³ is a substituted or unsubstituted monovalent hydrocarbon group,
b is an integer of 2 or more, d is an integer of 3 or more, c, e, and f are 0
Or it is an integer of 1 or more. )

Here, R ³ is a substituted or unsubstituted monovalent hydrocarbon group, preferably one having no aliphatic unsaturated bond, and one having 1 to 16 carbon atoms, especially 1 to 16 carbon atoms.
To 8, preferably alkyl groups such as methyl group, ethyl group, propyl group, butyl group and octyl group, cycloalkyl groups such as cyclohexyl group, aryl groups such as phenyl group and tolyl group, benzyl group, phenethyl group and the like. Aralkyl groups and the like, and chloropropyl groups in which some or all of these hydrogen atoms have been substituted with halogen atoms or cyano groups, and haloalkyl groups such as trifluoropropyl groups. A methyl group or a phenyl group is preferred.

The organohydrogenpolysiloxane has a viscosity at 25 ° C. of 1 to 500 cp, particularly 1 to 500 cp.
Those having 100 cp are preferably used.

The amounts of the components (A) and (B) are included in the total number of moles of hydrogen atoms directly bonded to silicon atoms contained in the organohydrogenpolysiloxane and in the organopolysiloxane containing alkenyl groups at both ends of the molecular chain. The molar ratio of alkenyl groups (hereinafter referred to as H / Vi) is 0.5
It is preferable to mix them so that H / Vi is 1 to 4, especially H / Vi is 1 to 4. If the H / Vi is less than 0.5, the primer composition may not be sufficiently cured, and if it exceeds 10, the temporal adhesion of the primer composition may be deteriorated.

The present composition is heated and cured using the platinum-based curing catalyst of the component (C) before use. Platinum or a platinum compound is preferable as the platinum curing catalyst. In this case, as the platinum compound, platinum black, chloroplatinic acid,
Examples thereof include alcohol-modified chloroplatinic acid, and complexes of chloroplatinic acid with olefins, aldehydes, vinylsiloxanes, acetylene alcohols, and the like.

The amount of the platinum-based curing catalyst is from 1 to 500 ppm, especially from 5 to 10 ppm in terms of platinum relative to the primer composition.
0 ppm is preferred. If the amount is less than 1 ppm, curing may not be sufficiently performed. If the amount exceeds 500 ppm, the adhesion with time of the primer composition is reduced, and at the same time, it is economically disadvantageous.

The reaction control component (D) used in the present invention suppresses the reaction of the composition at around normal temperature. Generally, a platinum-based curing catalyst is used to cure the alkenyl group-containing polysiloxane and the organopolysiloxane. An addition reaction composition generally used with hydrogen polysiloxane can be used.

As the reaction control agent, for example, acetylene alcohols, vinyl-containing siloxanes, silylated acetylene alcohols, or two or more reaction control agents proposed in JP-A-9-143371 are used in combination. Things are known. Specifically, 3-methyl-
1-butyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-penten-3-ol, 1-ethynylcyclohexanol, 1,1,3,
3-tetramethyl-1,3-divinyldisiloxane, methylvinylcyclotetrasiloxane, 3-methyl-3-
Trimethylsiloxy-1-pentyne and the like are exemplified.

The amount of the reaction control agent is as follows:
The total amount of the component (B) is preferably from 0.01 to 10 parts, particularly preferably from 0.1 to 5 parts, per 100 parts (parts by weight, hereinafter the same). If the amount is less than 0.01 part, the reaction controllability is poor, and if it exceeds 10 parts, the curability is poor.

The primer composition of the present invention further comprises, as a component (E), an organo having at least one epoxy group-containing organic group, one hydrogen atom and one alkoxysilyl group-containing alkyl group directly bonded to a silicon atom in one molecule. It is preferable to incorporate a polysiloxane, whereby the adhesion can be further improved.

As the component (E), those represented by the following general formula (5) or (6) can be used.

[0025]

Embedded image (In the formula, R ⁴ represents a hydrogen atom or R ³ , R ⁵ represents an epoxy group-containing organic group, R ⁶ represents an alkoxysilyl group-containing alkyl group, and R ³ is the same as described above. S, u, v, w , Y, z
Is an integer of 1 or more, and t and x are 0 or an integer of 1 or more. )

Here, the epoxy group-containing organic group includes:
The following are mentioned.

Embedded image (However, R ⁷ has 1 to 1 carbon atoms which may be interposed by an oxygen atom.
6, preferably 2 to 4 alkylene groups (or oxyalkylene groups). )

Specifically, the following can be exemplified.

[0028]

Embedded image

Examples of the alkoxysilyl group-containing alkyl group include the following.

Embedded image (Wherein, R ⁸ is 1 to 6 carbon atoms, preferably an alkylene group of 2 to 4, R ⁹ represents an alkyl group having 1 to 6 carbon atoms, R ²
Is the same as above, and m is an integer of 1 to 3, preferably 2
Or 3. )

Specifically, the following can be exemplified.

Embedded image

Specific examples of the component (E) include the following, but are not limited thereto.

[0032]

Embedded image

The amount of the component (E) is as follows.
(B) 0.01 to 10 with respect to 100 parts of the total amount of the components.
Parts, particularly preferably 0.1 to 1 part. If the amount is less than 0.01 part, improvement in adhesion may not be expected, and if it exceeds 10 parts, it is disadvantageous for curing the primer.

The primer composition of the present invention may further comprise, as component (F), one or more selected from fatty acids, acid anhydrides obtained by molecular condensation thereof, and intramolecular acid anhydrides. This organic compound also has a function that is extremely effective in improving the adhesion of the primer composition.

As the above additives, the following formula (7):
What is shown by (8) can be mentioned.

[0036]

Embedded image (In the formula, p is an integer of 1 to 10, preferably 1 to 5, R ¹⁰ is a hydrogen atom or a p-valent saturated or unsaturated carbon number of 1 to 30, preferably 5 to 20 substituted or unsubstituted. And q is an integer of 1 to 3, and R ¹¹ is a 2q-valent saturated or unsaturated carbon number of 1 to 3.
0, preferably 2 to 20 substituted or unsubstituted hydrocarbon groups. )

Here, the hydrocarbon group of R ¹⁰ and R ¹¹ includes an aryl group such as an alkyl group and a phenyl group, an aralkyl group, a combination of these groups, and a hydrogen atom of these monovalent hydrocarbon groups. Is a predetermined number of divalent or more hydrocarbon groups, a substituted hydrocarbon group in which a hydrogen atom of the hydrocarbon group is substituted with a halogen atom or a hydroxyl group, and two hydrogen atoms bonded to a carbon atom of an alkyl group Is substituted with an oxygen atom (that is, has a C ＝ O).

Examples of the component (F) include, but are not limited to, the following.

[0039]

Embedded image

The amount of the component (F) is as follows:
(B) 0.01 to 10 with respect to 100 parts of the total amount of the components.
Parts, particularly preferably 0.1 to 1 part. If the amount is less than 0.01 part, the adhesion may not be improved, and if it exceeds 10 parts, it is disadvantageous for curing the primer.

Furthermore, when the composition of the present invention is applied uniformly and thinly, it is advantageous to incorporate an organic solvent. The type and the amount of the organic solvent can be adjusted in consideration of the workability of coating the composition. Examples of the organic solvent include, for example, toluene, xylene, benzene, heptane, hexane, trichloroethylene, perchloroethylene, methylene chloride, ethyl acetate, and a solvent volatile oil. One or a combination of two or more may be used as a mixed solvent depending on the situation.

When the present composition is applied using a solvent,
For the purpose of further improving coatability, an alkenyl group-containing polyorganosiloxane having a degree of polymerization of 3,000 or more may be added as long as the effects of the present invention are not impaired. When the alkenyl group-containing polysiloxane is added, the amount of the component (B) may be increased as necessary.

In the composition of the present invention, additives such as known heat-resistant agents, coloring agents and antistatic agents such as red iron oxide, cerium oxide, cerium hydroxide, titanium oxide, carbon black, etc. Can be added in a range that does not impair the effects of the present invention.

The primer composition of the present invention is obtained by uniformly mixing the above components and uniformly applying the mixture to a plastic film.
Used by performing heat curing. The coating amount may be an amount sufficient to form a primer thin film on the surface of the plastic film, for example, 0.05 to 2.0 g / m
It is about ² and a large amount of coating is not preferable because it hinders the adhesion between the base material and the silicone adhesive. afterwards,
Perform heat curing. The temperature at the time of heating and curing differs depending on the film type and the coating amount, but is 80 ° C for 120 seconds to 180 ° C
May be appropriately selected within a range of about 15 seconds.

Here, examples of the plastic film substrate include polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polyimide resins, polyimide ether resins, epoxy resins, phenol resins, polyphenylene sulfide resins, ABS resins,
Examples thereof include a polyamide resin, a polycarbonate resin, a polystyrene resin, a polypropylene resin, a polyethylene resin, a polyvinyl chloride resin, and the like, and a laminate base material obtained by laminating a plurality of these resins.

As the silicone pressure-sensitive adhesive, known ones can be used. For example, an organic peroxide-curable type cured with an organic peroxide, or cured with a platinum-based catalyst (at room temperature or under heating). Examples include addition-curable silicone pressure-sensitive adhesives, and the primer composition of the present invention can be effectively used for addition-curable silicone pressure-sensitive adhesives.

[0047]

Industrial Applicability The primer composition of the present invention makes it possible to satisfactorily adhere a silicone pressure-sensitive adhesive to the surface of a plastic film substrate and to provide a pressure-sensitive adhesive composition having excellent adhesion durability, and is used in a wide range of fields. be able to.

[0048]

EXAMPLES The present invention will now be described specifically with reference to examples and comparative examples, but the present invention is not limited to the following examples. In addition, in the following examples, a part shows a weight part.

Examples 1 to 3 and Comparative Examples 1 to 4 The following components were uniformly stirred at room temperature to obtain five types of primer compositions.

Example 1 <1> 100 parts of diorganopolysiloxane having a vinyl group at both ends of the molecular chain (average degree of polymerization: 900, vinyl group content: 0.003 mol / 100 g), and organohydrogenpolysiloxane (hydrogen atom) Content 1.55 mol / 100g)
0.38 parts, 1-ethynylcyclohexanol 0.25
Parts, 1,900 parts of n-hexane and 100 ppm of platinum-based catalyst in terms of platinum (H / Vi = 1.94).

Example 2 <2> Diorganopolysiloxane having a vinyl group at both ends of the molecular chain (average degree of polymerization 1,300, vinyl group content 0.00)
100 parts of organohydrogenpolysiloxane (hydrogen atom content: 1.55 mol / 100 g)
g) 0.25 part, 1-ethynylcyclohexanol 0.1 g
25 parts, 1,900 parts of n-hexane, and 100 ppm of platinum-based catalyst in terms of platinum (H / Vi = 1.94).

Example 3 <3> Diorganopolysiloxane having a vinyl group at both ends of the molecular chain (average degree of polymerization 1,300, vinyl group content 0.00)
100 parts of organohydrogenpolysiloxane (hydrogen atom content: 1.55 mol / 100 g)
g) 0.25 part, 1-ethynylcyclohexanol 0.1 g
25 parts, 1,900 parts of n-hexane, 0.5 part of the component represented by the following structural formula (9) as the component (E), and 100 ppm of platinum-based catalyst in terms of platinum (H / Vi = 1.94).

[0053]

Embedded image

Comparative Example 1 <4> 100 parts of a diorganopolysiloxane containing a vinyl group at both molecular chain terminals (average degree of polymerization: 450, vinyl group content: 0.006 mol / 100 g), and an organohydrogenpolysiloxane (hydrogen atom) Content 1.55 mol / 100g)
0.75 parts, 1-ethynylcyclohexanol 0.25
Parts, 1,900 parts of n-hexane and 100 ppm of platinum-based catalyst in terms of platinum (H / Vi = 1.94).

Comparative Example 2 <5> 100 parts of a diorganopolysiloxane containing a vinyl group at both molecular chain terminals (average degree of polymerization: 450, vinyl group content: 0.006 mol / 100 g), and organohydrogenpolysiloxane (hydrogen atom) Content 1.55 mol / 100g)
0.75 parts, 1-ethynylcyclohexanol 0.25
Part, 1,900 parts of n-hexane, 0.5 part of the component (E) represented by the structural formula (9), and 100 ppm of a platinum-based catalyst in terms of platinum (H / Vi = 1.94).

Comparative Example 3 <6> 100 parts of a diorganopolysiloxane containing vinyl groups at both ends and side chains (average degree of polymerization: 4,000, vinyl group content: 0.002 mol / 100 g), organohydrogen 0.25 parts of polysiloxane (hydrogen atom content: 1.55 mol / 100 g), 0.25 parts of 1-ethynylcyclohexanol, 1,900 parts of n-hexane, represented by the structural formula (9) as the component (E) 0.5 parts,
100 ppm of platinum-based catalyst in terms of platinum (H / Vi = 1.
94).

Comparative Example 4 <7> No primer composition was used.

Next, the following evaluation was performed on the primer composition. In this case, a polyethylene terephthalate film (PE
T) and a polyimide film (PI) having a thickness of 25 μm were cut to a width of 25 mm, and the following silicone pressure-sensitive adhesive composition was used.

The addition-curable silicone pressure-sensitive adhesive (trade name:
X-40-3103 (Shin-Etsu Chemical Co., Ltd.)) 100
Parts, a mixture of 0.5 parts of a platinum-based catalyst (trade name: CAT-PL-50T (manufactured by Shin-Etsu Chemical Co., Ltd.)) and 50 parts of toluene, heated at 120 ° C. for 2 minutes, cured to give an adhesive tape I got

The organic peroxide-curable silicone pressure-sensitive adhesive is KR120 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.).
Using a mixture of 0 parts, 1.2 parts of benzoyl peroxide and 50 parts of toluene, the mixture was cured by heating at 150 ° C. for 5 minutes after air drying for 30 minutes to obtain an adhesive tape.

After applying the primer composition to the plastic film using a wire bar # 8,
After curing for 1 minute, and left for 4 hours, a silicone pressure-sensitive adhesive was applied to a thickness of 40 μm (after drying) and cured according to each curing method.

The adhesiveness was determined by cutting a 2 mm side of a 25 mm wide film substrate, then tearing and pulling from both sides.
Whether the adhesive rises above the film substrate (hereinafter,
When the adhesive was lifted over the entire surface, it was evaluated as x, when it was partially lifted, and when it was not recognized, it was evaluated as o. Furthermore, only the film was cut, and when pulled from both sides, the amount of elongation of the pressure-sensitive adhesive which was stretched without being cut was measured. If the adhesion is good, the elongation of the pressure-sensitive adhesive will be short. The adhesion with time of the primer was confirmed by applying the primer, exposing it to air at room temperature x 1 day after curing, and then rubbing the cured film of the primer before applying the adhesive with a finger to determine whether the primer was to fall off. The sample was evaluated as x when the sample was dropped, Δ when the sample was slightly dropped, and ○ when no sample was dropped. Table 1 shows the results.

[0063]

[Table 1]

Example 4, Comparative Examples 5 and 6 The following components were uniformly stirred at room temperature to obtain two kinds of primer compositions.

Example 4 <8> Diorganopolysiloxane having vinyl groups at both ends of molecular chain (average degree of polymerization 1,300, vinyl group content 0.00)
100 parts of organohydrogenpolysiloxane (hydrogen atom content: 1.55 mol / 100 g)
g) 0.25 part, 1-ethynylcyclohexanol 0.1 g
25 parts, 1,900 parts of n-hexane, 0.2 parts of a component represented by the following structural formula (10) as a component (F), and 100 ppm of platinum-based catalyst in terms of platinum (H / Vi = 1.9)
4).

[0066]

Embedded image

Comparative Example 5 <9> 100 parts of a diorganopolysiloxane having a vinyl group at both molecular chain terminals (average degree of polymerization: 450, content of vinyl group: 0.006 mol / 100 g), and organohydrogenpolysiloxane (hydrogen atom) Content 1.55 mol / 100g)
0.75 parts, 1-ethynylcyclohexanol 0.25
Parts, 1,900 parts of n-hexane, 0.2 parts of the component represented by the structural formula (10) as the component (F), and 100 ppm of a platinum-based catalyst in terms of platinum (H / Vi = 1.94).

Comparative Example 6 <10> No primer composition was used.

As the plastic film substrate, a polyphenylene sulfide (PPS) 25 μm thick, a polyethylene terephthalate film (PET) 25 μm thick, and a polyimide film (PI) 25 μm thick cut to a width of 25 mm are used. The following compositions were used.

The addition-curable silicone pressure-sensitive adhesive (trade name:
X-40-3103 (Shin-Etsu Chemical Co., Ltd.)) 100
Parts, a mixture of 0.5 parts of a platinum-based catalyst (trade name: CAT-PL-50T (manufactured by Shin-Etsu Chemical Co., Ltd.)) and 50 parts of toluene, heated at 120 ° C. for 2 minutes, cured to give an adhesive tape I got

Thereafter, sample preparation and evaluation were performed in the same manner as in Examples 1 to 3. Table 2 shows the results.

[0072]

[Table 2]

From the results shown in Tables 1 and 2, it was confirmed that the primer composition of the present invention had an excellent effect on improving the adhesion between various plastic films and the silicone adhesive.

Continued on the front page (72) Inventor Masahiko Ogawa 1-10 Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture F-term in the Silicon Electronics Research Laboratory, Shin-Etsu Chemical Co., Ltd. (Reference) 4J038 DL042 DL051 DL111 FA212 GA02 GA07 HA136 JA19 JA39 JA41 JA42 JC32 KA04 MA14 NA10 NA12

Claims (3)

[Claims] (A) A diorganopolysiloxane having an alkenyl group at both ends of a molecular chain and having an average degree of polymerization of 500 to 2,000, wherein the number of moles of the alkenyl group contained in the diorganopolysiloxane is 1. 0.001 to 0.005 mol per 100 g of diorganopolysiloxane, (B) an organohydrogenpolysiloxane having at least two hydrogen atoms directly bonded to silicon atoms in one molecule, (C) a platinum-based curing catalyst, (D) A primer composition for a silicone pressure-sensitive adhesive, comprising a reaction control agent. 2. The composition according to claim 1, wherein (E) an organopolysiloxane having at least one epoxy group-containing organic group, one hydrogen atom and one alkoxysilyl group-containing alkyl group directly bonded to a silicon atom in one molecule. object. 3. The composition according to claim 1, further comprising (F) one or more additives selected from fatty acids, acid anhydrides obtained by molecular condensation thereof, and intramolecular acid anhydrides.