JP2971357B2 - Peeling composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a release composition, and more particularly, to a composition which is cured by a hydrosilylation reaction to form a release film exhibiting release properties for an adhesive or tacky substance. With excellent curability, the resulting coating does not suffer from a decrease in peelability due to exposure of the coated surface to the outside air, peels off with a light peeling force at low and high speed peeling, and has excellent residual adhesion rate And a release composition showing a stable light release force immediately after curing.

[0002]

2. Description of the Related Art Utilizing that polyorganosiloxane does not show affinity for various substances and shows releasability for adhesive or tacky substances, it can be used for various fibers such as paper and synthetic. It is well known that a surface of various substrates such as a resin film is treated and a cured film is formed by a crosslinking reaction, and is used as a peelable film for an adhesive or tacky substance.

[0003] Such curable polyorganosiloxane compositions include polyorganosiloxanes containing an alkenyl group such as a vinyl group bonded to a silicon atom;
A polyorganohydrogensiloxane having a hydrogen atom bonded to a silicon atom as a main component, and an addition-reaction type stripping composition cured by a hydrosilylation reaction;
Further, a condensation reaction-type release composition comprising a silanol group-containing polyorganosiloxane and the above-mentioned polyorganohydrogensiloxane as main components and cured by dehydrocondensation is known. The addition reaction type is widely used as a release composition because it has advantages such as a higher curing speed and a smaller release speed dependency of the release force than the condensation reaction type. However, the addition-removable release composition exhibits a phenomenon in which the release performance is lost when the cured film is exposed to the open air. Therefore, using a release paper or a release film on which a release coating is formed using an addition-reaction type release composition, the coating is exposed to the air in the process of producing labels and adhesive tapes. In such a case, these products cannot exhibit their original peeling property, and cannot be peeled, resulting in a serious deterioration in quality.

In order to solve such a problem, a method of blending an alcohol-modified polyorganosiloxane or a polyether-modified polyorganosiloxane with an addition-reaction type stripping composition (Japanese Patent Application Laid-Open No. 55-3460), And as part of the polyorganohydrogensiloxane,
A method of compounding a compound having a hydrosilyl group only at one terminal siloxy group of a polysiloxane chain (Japanese Patent Laid-Open No. 1-21)
No. 7068) and a method in which a silicone rubber having a high vinyl group content and a polyorganohydrogensiloxane having a specific molar ratio are used, and a polydiorganosiloxane having a hydroxyl group is further compounded (JP-A-6-93183).
Is known. However, Japanese Patent Application Laid-Open No. 55-346
According to the methods described in Japanese Patent Application Laid-Open No. 0-210679 and Japanese Patent Application Laid-Open No. Hei 1-217068, a certain effect on the above-described stability to exposure to the atmosphere (hereinafter referred to as exposure resistance) is recognized, but is not sufficient. There is a problem that the transfer amount of the release agent to the adhesive layer is increased, and the residual adhesive force is reduced.
On the other hand, the method described in JP-A-6-93183 has a problem in that the peeling force immediately after curing is heavy, and it takes a number of days for the peeling force to stabilize. In particular, when processing is performed at a low temperature, such as in winter, the peeling force is heavy and unstable, so that a situation where shipment cannot be performed for a long time may occur.

The present inventors have previously described the content of Si—H bonds in a polyorganohydrogensiloxane used as a crosslinking agent, and the vinyl bonded to the Si—H bonds and silicon atoms in the vinyl-containing polyorganosiloxane. By limiting the ratio to the specific range to a specific range, a release composition having excellent exposure resistance was obtained (JP-A-6-322).
295). However, with the diversification of requirements for release papers and release films, there has been a demand for release compositions that provide release coatings that satisfy various properties in a comprehensive manner.

That is, when an adhesive paper is manufactured using a release paper or a release film, the adhesive paper is peeled at a high speed in order to improve productivity in a rewinding step, a descaling step, a label attaching step, and the like in the manufacturing process. Is needed. Even in the case of a peelable film exhibiting a light peeling force at a low speed, if the film is peeled at a high speed, the peeling force may become extremely heavy, so it is also important to reduce the peeling force at the time of high-speed peeling. It has become a challenge. A method of blending a non-reactive aryl group-containing polyorganosiloxane with an addition reaction-type release composition in order to improve this high-speed release property (Japanese Patent Application Laid-Open No. Sho 60-133051).
A method of blending a polyorganosiloxane having a hydroxyl group at the terminal and containing an aryl group (Japanese Patent Application Laid-Open No. 3-9385)
No. 8) and a method in which a polyorganosiloxane having a high vinyl group content and containing a phenyl group is used in combination with a polyorganosiloxane having a low vinyl group content (Japanese Patent Laid-Open No. -187466) is known. But,
These methods have some effect in reducing the peeling force at the time of high-speed peeling as described above, but they are not sufficient. In particular, in the method described in JP-A-3-93858, the above-mentioned method has a problem in that Those having a small amount of a polyorganosiloxane having a hydroxyl group and containing an aryl group have a large peeling force at the time of low-speed peeling, and those having a large amount of addition have an extremely low residual adhesion rate. Not practical.

In recent years, it has been required to impart a plurality of properties to a release paper or a release film used for a pressure-sensitive adhesive product to differentiate them. However, even if the exposure resistance is imparted as described above, the peeling force immediately after curing is heavy, and even if it takes days to stabilize the peeling force, or if the peeling force at the time of high-speed peeling is reduced, even at a low speed, The obtained peelable film has advantages and disadvantages such as a heavy peeling force, and it has been difficult to provide a peelable film that can sufficiently satisfy a plurality of characteristics.

[0008]

SUMMARY OF THE INVENTION The present invention solves the problems of such an addition-reaction type stripping composition.
The purpose is for exfoliation that excels in curability and exposure resistance, peels with a light peeling force at low and high speed peeling, and shows stable peeling force immediately after curing without degrading migration and residual adhesion. It is to provide a composition.

[0009]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve this problem, and as a result, using an alkenyl group-containing polyorganosiloxane as the component (A),
(D) A high molecular weight polydimethylsiloxane having a hydroxyl group (B) is added to a release composition which is cured by an addition reaction with a polyorganohydrogensiloxane as a component.
And a specific amount of polydiorganosiloxane (C) having a hydroxyl group and containing an aryl group,
The problem to be solved by the present invention, that is, exfoliation having multiple properties, showing excellent curability, exposure resistance, light peeling force at low speed and high speed peeling, showing a stable peeling force immediately after curing. It has been found that providing a functional film has an excellent effect, and the present invention has been completed.

That is, the present invention provides the following component (A):
The present invention relates to a stripping composition containing component (B), component (C), component (D) and component (E).

(A) The compound has two or more alkenyl groups bonded to a silicon atom in one molecule, the remaining organic group bonded to the silicon atom is a methyl group or a phenyl group, and has a viscosity at 25 ° C. of 50 cP or more. 100 parts by weight of a certain polyorganosiloxane; (B) one or more hydroxyl groups bonded to a silicon atom in one molecule, the organic group bonded to the silicon atom is a methyl group, and a 30% by weight toluene solution at 25 ° C. Viscosity 1
Polydimethylsiloxane having a molecular weight of at least 000 cP
(C) 6 to 2 aryl groups having one or more hydroxyl groups bonded to a silicon atom in one molecule and bonding to a silicon atom.
0 mol%, viscosity at 25 ° C. is 5,000-
500,000 cP polydiorganosiloxane 0.1
(D) a linear polyorganohydrogensiloxane represented by the formula (I) having at least three hydrogen atoms bonded to silicon atoms per molecule on average, and hydrogen bonded to silicon atoms; An amount of 2.3 to 4.0 atoms per atom of the alkenyl group in the component (A),

Embedded image (In the formula, R ^1, taken together, may the same or different, represent a hydrogen atom, a methyl group or a phenyl group; R ²
Each may be the same or different and represents a methyl group or a phenyl group; a and b each represent a positive integer; and the ratio of the number of siloxane units containing Si—H bonds to the total number of siloxane units is 0.45. (E) platinum or a platinum compound catalyst amount.

Hereinafter, the composition of the present invention will be described in more detail.

<Component (A)> The alkenyl group-containing polyorganosiloxane of the component (A) is a component used as a base polymer in the release composition of the present invention. The component (A) has two or more alkenyl groups directly bonded to a silicon atom in one molecule, and the alkenyl group forms a network structure by reaction with a hydrosilyl group of the component (D) described later. Thereby, the composition can be cured to form a peelable film. Each of the alkenyl groups is preferably bonded to a different silicon atom, and may be bonded to any of the terminal silicon atom and the intermediate silicon atom of the siloxane chain. In order to obtain a film having excellent mechanical strength, it is more preferable that an alkenyl group is bonded to at least the terminal silicon atom of the siloxane chain.

Alkenyl groups include vinyl, allyl,
Butenyl, hexenyl and the like are exemplified, and a vinyl group is preferable since good release characteristics can be obtained.

As described above, the amount of the alkenyl group is 2 or more in one molecule, and the curability, the physical properties of the cured film, the amount of the component which migrates from the film to the adhesive layer is small, and the residual adhesion ratio is low. The alkenyl group-containing siloxane unit is preferably in the range of 0.5 to 10 mol% based on the total siloxane unit because of its high cost and easy production of the base polymer.
-6 mol% is particularly preferred.

An organic group other than an alkenyl group bonded to a silicon atom must have a film obtained by curing having excellent releasability, mechanical strength, and fluidity before curing, and also having the exposure resistance which is the object of the present invention. From is substantially a methyl or phenyl group. In particular, in order to give the coating excellent exposure resistance, it is preferable that 85% or more of the organic groups are methyl groups, and it is more preferable that all of the organic groups are methyl groups.

The siloxane skeleton of the component (A) may be linear or branched, and these may be used in combination to impart excellent mechanical properties to the film. As described above, the viscosity is 50 cP or more at 25 ° C., and preferably 100 cP or more. If the viscosity is less than 50 cP, it is not possible to give sufficient peelability and mechanical strength to the cured film, especially when using a substrate such as glassine paper or kraft paper,
If the viscosity is low, there is a tendency that the resin penetrates into the base material much, and the releasability when using the same treatment amount is poor.

<Component (B)> The component (B) has at least one hydroxyl group bonded to a silicon atom in one molecule, and the organic group bonded to the silicon atom is a methyl group. Is a silicone rubber-like high molecular weight polydimethylsiloxane having a viscosity at 25 ° C. of 10,000 cP or more. The polydimethylsiloxane is a component for reducing the peeling force and developing the exposure resistance in the peeling composition of the present invention. Because it is easy to handle,
The viscosity at 25 ° C. of the 30% by weight toluene solution of the component (B) is preferably in the range of 10,000 to 1,000,000 cP, particularly preferably in the range of 15,000 to 100,000 cP. Polydimethylsiloxane having a viscosity of less than 10,000 cP cannot provide sufficient effects on light peeling and exposure resistance, and further deteriorates migration property.
This leads to a decrease in the residual adhesion rate. The hydroxyl group may be bonded to any of the terminal silicon atom and the intermediate silicon atom of the siloxane chain, but is preferably bonded to the terminal silicon atom because of easy synthesis. 1
More preferably, two hydroxyl groups are bonded.

Generally, non-reactive polydimethylsiloxane is sometimes used as a component for reducing the peeling force. However, the transferability of the peelable film is increased, and the residual adhesion ratio is deteriorated. However, the component (B) used in the present invention does not increase the migration property or lower the residual adhesive ratio while maintaining the property of reducing the peeling force.

The amount of the component (B) is 100 parts (A)
5 to 30 parts by weight with respect to parts by weight, and 10 to 2 parts by weight.
0 parts by weight is preferred. If the amount exceeds 30 parts by weight, the peeling force at a low speed becomes light, but the peeling force at a high speed becomes conversely heavy, which causes problems such as deterioration of transferability and reduction of a residual adhesive ratio. If the amount is less than 5 parts by weight, sufficient light peelability and exposure resistance cannot be exhibited.

<Component (C)> The component (C) has at least one hydroxyl group bonded to a silicon atom in one molecule and contains 6 to 20 mol% of an aryl group bonded to a silicon atom. It is a polydiorganosiloxane having a viscosity at 500C of 500 to 500,000 cP. The aryl group-containing polydiorganosiloxane is a component for the release composition of the present invention to exhibit stable light release properties immediately after curing. When the aforementioned component (B) is used alone without being used in combination with this component (C), a light peeling force is developed,
The peeling force immediately after curing is heavy, and it takes several days for the above light peelability to be sufficiently exhibited. By blending the components (B) and (C) in combination, unexpectedly, a stable and good light peeling property can be obtained immediately after the curing, and no decrease in migration property and residual adhesiveness is exhibited. The effect is obtained.

The aryl groups contained in the component (C) may be the same or different, and include phenyl and tolyl. A phenyl group is preferable since good peeling characteristics can be obtained. The content of such an aryl group is 6 to
It is 20 mol%, and preferably 8 to 16 mol%. When the amount of the aryl group is less than 6 mol%, it is difficult to develop a stable and light peeling force immediately after curing, and when the amount exceeds 20 mol%, the effect is not improved. On the other hand, the components (A) and (B) And the component (C) is not uniformly dispersed, resulting in deterioration in the migration of the releasable film and decrease in the residual adhesion rate. The aryl group may be attached to any silicon atom of the siloxane chain. In the case of an intermediate silicon atom, the number of aryl groups bonded to the silicon atom may be one or two. Examples of the remaining organic group bonded to the silicon atom include alkyl groups such as methyl, ethyl, propyl, butyl, and pentyl.Since synthesis and handling are easy and excellent physical properties and releasability are provided, substantially Preferably, all are methyl groups. The hydroxyl group may be bonded to any of the terminal silicon atom and the intermediate silicon atom of the siloxane chain, but is preferably bonded to the terminal silicon atom because of easy synthesis. More preferably, one hydroxyl group is bonded.

The viscosity of the component (C) at 25 ° C. is 5,0
100 to 500,000 cP and 10,000 to 30
Preferably, it is 0000 cP. 5,000 viscosity
When the viscosity is less than cP, not only is it difficult to develop a stable and light peeling force immediately after curing, but also the residual adhesiveness decreases. On the other hand, when the viscosity exceeds 500,000 cP, the effect of expressing a stable light peeling force immediately after curing is small.

The amount of the component (C) is 100 parts.
0.1 to 5.0 parts by weight with respect to parts by weight, and 0.1 to 5.0 parts by weight.
2.0 parts by weight is preferred. If it is less than 0.1 part by weight, it is difficult to develop a stable light peeling force immediately after curing,
If it exceeds 5.0 parts by weight, the migration property and the residual adhesion rate are remarkably reduced.

Further, when the total amount of the component (B) and the component (C) is 10 to 20 parts by weight with respect to 100 parts by weight of the component (A), the curability and the exposure resistance are excellent and the migration is improved. It is most preferable in the present invention because it exhibits a stable and light peeling force immediately after curing without reducing the properties and the residual adhesion rate.

<Component (D)> The polyorganohydrogensiloxane of the component (D) is a component used as a crosslinking agent in the release composition of the present invention. That is, a network structure is formed by performing an addition reaction between the hydrosilyl group contained in the component (D) and the alkenyl group contained in the component (A). Therefore, the number of hydrogen atoms directly bonded to silicon atoms in the component (D) needs to be at least three on average in one molecule. Further, the polyorganohydrogensiloxane is used in order for the composition to cure to give a release agent film having excellent exposure resistance.
It is necessary to have a specific molecular structure, as well as a ratio of the number of siloxane units containing Si-H bonds to the total number of siloxane units. Such a polyorganohydrogensiloxane is a linear polyorganohydrogensiloxane represented by the following formula (I).

[0027]

Embedded image

(Wherein R ¹ , R ² , a and b are as described above) The formula (I) simply shows the constitutional ratio of siloxane units, and the linear polyorganohydrogensiloxane is Any of a random copolymer and a block copolymer may be used, and the former is generally used. In the formula (I), the siloxy groups at both terminals may be such that R ¹ is a hydrogen atom, a methyl group or a phenyl group. When R ^{1 at} both ends is a hydrogen atom, the number a ′ of the siloxane units containing Si—H bonds in the polyorganohydrogensiloxane is a + 2. When R ^{1 at} one end is a hydrogen atom, a ′ is a + 1, and R 1 at both ends is R + 1.
^{When 1} is a methyl group or a phenyl group, a 'is equal to a. Such a ′ and the number of all siloxane units (a +
b + 2) ratio a ′ / (a + b + 2) is 0.45 to 1.0
0, preferably in the range of 0.45 to 0.75. If this value is less than 0.45, the rate of the addition reaction at the time of curing becomes slow, and the curability is poor.

The organic group bonded to the silicon atom, ie, R
¹ (except when it is a hydrogen atom) and R ² are a methyl group or a phenyl group because they give excellent exfoliation resistance to the release film obtained by curing, and 85% of the organic group in the molecule. % Or more is preferably a methyl group, more preferably all methyl groups.

The viscosity is not particularly limited, but the viscosity at 25 ° C. is 500 cP because of easy synthesis and handling.
The following is preferred.

The compounding amount of component (D) is such that the number of hydrogen atoms bonded to silicon atoms in component (D) is 2.3 to 4.0 per alkenyl group in component (A). Quantity
Thereby, the peelable coating obtained by curing has excellent exposure resistance. Further, within the above range, the amount of the component (D) is 0.5 to 1 with respect to 100 parts by weight of the component (A).
The average molecular weight of both components, the content of the alkenyl group bonded to the silicon atom of the component (A), and the content of the hydrogen atom bonded to the silicon atom of the component (D) are selected so as to be 00 parts by weight. Is preferred. This amount is 0.5
If the amount is less than parts by weight, it is difficult to uniformly disperse the component (B) in the component (A) in a short time, which imposes restrictions on work.
In addition, in a combination in which this amount exceeds 100 parts by weight,
The residual adhesion rate decreases, and the migration property deteriorates.

<Component (E)> The platinum or platinum compound of the component (E) acts as a catalyst for the hydrosilylation reaction between the alkenyl group in the component (A) and the Si—H bond in the component (D). It is a curing catalyst, and a platinum compound is preferred from the viewpoint of catalytic effect. Examples of the platinum compound include chloroplatinic acid, a reaction product of chloroplatinic acid and an alcohol, a platinum-olefin complex, a platinum-vinylsiloxane complex, a platinum-phosphorus complex, and a platinum coordination compound.

The compounding amount of the component (E) is an effective amount as a catalyst, and is usually in the range of 1 to 500 ppm as platinum atom with respect to the total amount of the components (A) and (D).
300 ppm is preferred. If it is less than 1 ppm, curing is extremely slow, which is disadvantageous in practical use. If it exceeds 300 ppm, a corresponding improvement in curing speed cannot be expected, which is not preferable in terms of economy and stability.

<Other Additives> Known additives may be added to the composition of the present invention, if necessary, as long as the function of the composition of the present invention is not impaired. Such additives include inorganic fillers such as fumed silica, pigments such as red iron, curing inhibitors such as 2-methyl-3-butyn-2-ol, and 2-hydroxy-2-methyl. Photosensitizers such as -1-phenylpropan-1-one can be exemplified.

<Method of Use> The composition of the present invention may be applied to a substrate as it is when the apparent viscosity of the system is low, but it is diluted with a solvent in consideration of workability of application and processing. It is generally used. As the solvent, benzene, toluene,
Aromatic hydrocarbons such as xylene; aliphatic hydrocarbons such as heptane and hexane; halogenated hydrocarbons such as tetrachloroethylene; esters such as ethyl acetate and butyl acetate; and ketones such as methyl ethyl ketone and methyl isobutyl ketone; Is exemplified.

The composition of the present invention usually comprises (A) to (D)
The components and, if necessary, additives and solvents are mixed, and the separately prepared component (E) or a solution thereof is mixed immediately before use and applied to a substrate. If necessary, the component (D) may be separately stored, or a mixture of the components (A) to (D) or a solution thereof may be stored in the presence of a curing inhibitor.

As the base material, glassine paper, kraft paper,
Examples include, but are not limited to, paper or paper composites such as parchment paper and polyethylene laminated paper; and plastic films such as polyethylene film and polypropylene film.

After the application, if a solvent is present, it is dried to remove the solvent, and then heated and cured to form a peelable film on the surface of the substrate. The heating condition is usually at a temperature of 100 to 1
10 to 30 seconds at 50 ° C.

[0039]

The release composition of the present invention has excellent curability,
The peelable coating obtained by curing it has excellent exposure resistance, peels off with a light peeling force at low and high speed peeling, and has no characteristic of migration, no decrease in residual adhesive rate, and it is especially characteristic. In particular, it shows a stable light peeling force immediately after curing. Accordingly, a release paper or a release film in which a release film obtained from the release composition of the present invention is formed on the surface of a substrate, the release force does not increase even when the release agent-coated surface is exposed to the open air. Since the peeling force at low and high speed peeling is light, excellent in transferability and residual adhesion rate, it shows stable light peeling force immediately after hardening even when processed at low temperature as in winter, so in terms of quality stabilization. It is advantageous and has great industrial significance.

[0040]

The present invention will be described more specifically with reference to the following examples and comparative examples. The present invention is not limited by these examples. In the following examples and comparative examples, parts represent parts by weight, and the viscosity indicates a value at 25 ° C.

In Examples and Comparative Examples, various polysiloxanes shown in Table 1, that is, A-1 to A-1 as component (A) were used.
A-3, B-1 to B-3 as the component (B), C-1 to C-7 as the component (C), and D- as the component (D).
1 and D-2 were used. Of these, B-2, B-
3 and C-4 to C-7 are polyorganosiloxanes for comparison. In the following description and the molecular structural formulas in Table 1, siloxane units are represented by the following abbreviations. The molecular structural formula means the composition ratio of siloxane units, and each polysiloxane is a random copolymer. M: (CH ₃ ) ₃ SiO _1/2 unit M ′: (CH ₃ ) ₂ HSiO _1/2 unit M ^v : (CH ₃ ) ₂ (CH ₂ ＣＨCH) SiO _1/2 unit M ^OH : HO (CH _{3) 2} SiO _1/2 units D: (CH _{3) 2} SiO units D': (CH ₃₎ HSiO units _{^{D v: (CH 3) (}} CH 2 = CH) SiO unit ^{_{D ph2: (C 6 H 5}} ) ₂ SiO units

[0042]

[Table 1]

Further, as the component (E), a platinum-vinylsiloxane complex obtained from chloroplatinic acid and tetravinyltetramethylcyclotetrasiloxane and having a platinum content of 4,500 ppm was used. Further, if necessary, 2-methyl-3-butyne-2 may be used as a curing inhibitor.
-All, toluene was used as a solvent.

Examples 1 to 6 and Comparative Examples 1 to 13 The components (A) to (E) and, if necessary, a curing inhibitor and a solvent were mixed according to the mixing ratios shown in Table 2,
The treatment liquids of Examples 1 to 6 and Comparative Examples 1 to 13 were respectively prepared by stirring and mixing until uniform. In Table 2, A-2, A-3, B-1 to B3, and C-1
C-7 indicates the number of added parts in the state of a 30% by weight toluene solution.

For example, the treatment liquid of Example 1 was prepared as follows. That is, a polymethylvinylsiloxane A-1 having a polymerization degree of 200 and having both ends blocked with a dimethylvinylsilyl group and containing 2.0 mol% of a methylvinylsiloxane unit and the remaining dimethylsiloxane unit is 100 parts.
Part: polydimethylsiloxane having a polymerization degree of 4,500 and both ends blocked with a dimethylhydroxysilyl group (viscosity of a 30% by weight toluene solution at 25 ° C. is 15,000)
cP) 10 parts of B-1; polymethylphenylsiloxane having both ends capped with a dimethylhydroxysilyl group and consisting of 10.0 mol% of diphenylsiloxane units and the remaining dimethylsiloxane units (viscosity at 25 ° C of 20,000)
0cP) 2.0 parts of C-1; both ends are blocked with a trimethylsilyl group, and methylhydrogensiloxane units 58
6.76 parts of polymethylhydrogensiloxane (degree of polymerization 62) D-1 consisting of mol% and the remaining dimethylsiloxane units; and 0.1 part of 2-methyl-3-butyn-2-ol are uniformly mixed. After that, 4.12 parts of a platinum-vinylsiloxane complex E-1 was added to prepare a treatment liquid. For one Si-Vi bond in A-1, D-1
The number of Si-H bonds in the sample was 2.5.

[0046]

[Table 2]

These treatment liquids were applied to a polyethylene laminated paper having a density of 75 g / m ² so that the coating amount after drying was 0.8 g / m ² , and cured by heating at 100 ° C. for 20 seconds. A release coating was formed on the surface of the polyethylene laminated paper.

The resulting peelable coating was evaluated as follows. As a result, the results shown in Table 3 were obtained.

[0049]

[Table 3]

<Release Force (Low Speed)> After curing, the acrylic film was sealed in a paper container and cured for one day at 25 ° C. and 50% RH.
S-8170 (trade name, manufactured by Toyo Ink Co., Ltd.) was applied so that the wet thickness became 88 μm, and dried at 100 ° C. for 3 minutes. Next, high-quality paper having a unit weight of 60 g / m ² was peeled thereon, and the whole was cut into a strip having a width of 5 cm. This is 2
Under a load of 0 g / cm ² , temperature 25 ° C, relative humidity 50%
The sample was cured for one day under the conditions described above. This sample was pulled in a 180 ° direction at a speed of 0.3 m / min by a tensile tester, and the force required for peeling was measured.

<Peeling Force (High Speed)> The Peeling Force (Low Speed)
A sample prepared in the same manner as in the above evaluation method was pulled in a 180 ° direction at a speed of 60 m / min by a tensile tester, and the force required for peeling was measured.

<Peeling Force (After Exposure)> The sample having a releasable film obtained by curing was exposed outdoors to the air for 4 hours with the treated side facing up. Using this, the peeling force was measured under the same measurement conditions as the peeling force (low speed).

<Peeling force (after 3 days)> After curing, a sample sealed in a paper container and cured at 25 ° C. and 50% RH for 3 days was used under the same measurement conditions as the peeling force (low speed). Was measured.

<Residual Adhesive Strength> Nitto 31B adhesive tape having a width of 2.5 cm (Nitto Denko Corporation)
Product name). After leaving this at 70 ° C. for 20 hours under a load of 20 g / cm ² , the tape was peeled off from the surface of the release agent coating, and the surface in contact with the release agent was attached to a stainless steel plate (JIS C2107). And pressed with a 2 kg roller. This was cured at 25 ° C. for 3 hours, pulled in a 180 ° direction by a tensile tester, and the peeling force (f) of the tape was measured. On the other hand, the same kind of adhesive tape is stuck on polytetrafluoroethylene film,
Thereafter, by the same operation, the reference peeling force (f
_o ) was measured. The residual adhesion rate was calculated by the following equation.

[0055]

(Equation 1)

<Migration> The polyethylene laminated paper provided with the release coating as described above was cut into a strip having a width of 5 cm. A PET film having a thickness of 25 μm was stuck on the surface of the peelable film, a load of 100 g / cm ² was applied, and the film was pressed at 65 ° C. for 20 hours. Then, the film was peeled off and the PET film in contact with the peelable film was peeled off. A line was drawn with Magic Ink (Hi Mackie: manufactured by Zebra Corp., trade name), and the repelling condition of the ink was observed.

From the formulations shown in Table 2 and the evaluation results in Table 3,
Example 3 is compared with Comparative Examples 12 and 13. The peelable film obtained in Example 3 in which the component (B) and the component (C) are used in combination reduces the peeling force (after exposure), the residual adhesion rate, and the migration property due to a synergistic effect of the two components. Without
Stable light peeling force was exhibited immediately after curing. On the other hand, Comparative Examples 12 and 13 using the component (B) or the component (C) alone exhibited excellent peeling force (after exposure),
Although showing the residual adhesiveness and migration, the peeling force immediately after curing was heavy, and a change with time in the peeling force was observed.

Continuation of the front page (51) Int.Cl. ⁶ identification symbol FI C09D 183/07 C09D 183/07 C09J 7/02 C09J 7/02 Z (58) Investigated field (Int.Cl. ⁶ , DB name) C08L 83 / 07 C08L 83/05 C08L 83/06 C09D 183/05 C09D 183/06 C09D 183/07 C09J 7/02

Claims (2)

(57) [Claims] 1. The following components (A), (B) and (C)
A release composition comprising the components, (D) and (E) in the following proportions . (A) a polyorgano having two or more alkenyl groups bonded to a silicon atom in one molecule, the remaining organic group bonded to the silicon atom being a methyl group or a phenyl group, and having a viscosity at 25 ° C. of 50 cP or more. siloxane, 100 parts by weight; (B) water acid groups are bonded to the silicon atoms at both ends, a viscosity at 25 ° C. for 3 0 wt% toluene solution 10,000cP
The in which polydimethylsiloxane or more, 5 to 30 parts by weight; (C) water acid groups are bonded to the silicon atoms at both ends, and the bound aryl group containing 8-20 mol% silicon atoms, at 25 ° C. 5,000-500,000 viscosity
The polydiorganosiloxane which is cP is 0.1 to 5.0
Parts; having an average of at least three in one molecule (D) a hydrogen atom bonded to a silicon atom, a linear polyorganohydrogensiloxane of formula (I), a hydrogen atom bonded to a silicon atom (A) an amount of 2.3 to 4.0 per alkenyl group in the component; (In the formula, R ^1, taken together, may the same or different, represent a hydrogen atom, a methyl group or a phenyl group; R ²
Each may be the same or different and represents a methyl group or a phenyl group; a and b each represent a positive integer; and the ratio of the number of siloxane units containing Si—H bonds to the total number of siloxane units is 0.45. ~ is 0.75); (E) platinum or a platinum compound catalyst amounts. 2. A release coating obtained by curing the release composition according to claim 1.