JPH07157727A - Releasable treatment agent - Google Patents

Abstract

PURPOSE:To obtain a releasable treatment agent containing a specific resin having siloxane segment, crosslinkable with water and moisture in air to enable the single-component curing and capable of making a releasable surface on the back of a substrate of a tape, etc., contacting with a tacky adhesive face or on the surface of a releasing paper. CONSTITUTION:This treating agent is composed of a resin containing a siloxane segment, free from free isocyanate group and having hydrolyzable silyl group and produced by the reaction of a polysiloxane compound having reactive organic functional group [e.g. an amino-modified polysiloxane compound of formula ((m) is 1-10; (n) is 2-10; R is CH3 or OCH3)] with a silane coupling agent having reactive organic functional group [e.g. a silane coupling agent having free isocyanate group and expressed by formula (CH3O)3Si(CH2)3NCO] and an organic polyisocyanate (e.g. toluene-2,4-diisocyanate). The agent may contain other resins as necessary and is cured by using moisture as the curing agent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a releasable treatment agent, and more particularly to a back surface of a base material such as a tape which is in contact with an adhesive surface in a product using the adhesive such as an adhesive tape, an adhesive label and an adhesive sheet. The present invention also relates to a releasable treatment agent capable of imparting releasability to the surface of release paper.

[0002]

2. Description of the Related Art Conventionally, as a peeling treatment agent used for the above purpose, an acrylic acid-based agent having a long-chain alkyl group bonded,
Polymer compounds such as polyesters and polyamides and organopolysiloxane compounds are known, and are used to form a release surface by imparting releasability to the back of adhesive tape or sheet or the surface of release paper. Has been done. Among these peeling treatment agents, it is known that organopolysiloxane compounds are excellent in characteristics such as peelability and residual adhesiveness.

[0003]

[Problems to be solved by the invention] However,
It is difficult for conventional organopolysiloxane compounds to obtain a suitable peeling force, and since high temperature baking is required when coating on a substrate, it cannot be used for a thermoplastic substrate film. There was a problem. Further, there is a drawback that it cannot be used for all kinds of substrates because the adhesion to the substrate is insufficient depending on the substrate.

As a method for solving the above problems, the present applicant has previously used a silicone copolymer as a release treatment agent, which enables low-temperature baking, and has adhesiveness to a substrate and a release surface. It was proposed to obtain an excellent releasability treatment agent which also has writing property to the like. Therefore, an object of the present invention is to further improve the above-mentioned conventional technique, to provide a peeling treatment agent having a simplified process of forming a peeling treatment agent layer and having excellent performance.

[0005]

The above object can be achieved by the present invention described below. That is, the present invention is a release treatment agent containing a resin having a siloxane segment,
The resin is a reaction product of a polysiloxane compound having a reactive organic functional group, a silane coupling agent having a reactive organic functional group, and an organic polyisocyanate, which has no free isocyanate group and is hydrolyzable silyl. A releasable treatment agent comprising a resin having a group.

[0006]

The peeling treatment agent layer is formed by a reaction product of a polysiloxane compound having a reactive organic functional group, a silane coupling agent having a reactive organic functional group, and an organic polyisocyanate. Since the agent layer has a hydrolyzable silyl group, the agent layer is cross-linked by moisture and humidity in the air, so that one-part curing is possible and the step of forming the peeling treatment agent layer is simplified. Further, the presence of the hydrolyzable silyl group improves the adhesion of the release treatment agent layer to the base sheet, and forms a release treatment agent layer having excellent performance.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the preferred embodiments. Preferred examples of the reactive organic functional group-containing polysiloxane compound used in the present invention include the following compounds.

(1) Amino-modified polysiloxane compound

[0009]

[0010] (2) Epoxy-modified polysiloxane compound

[0011]

[0012] The above epoxy compound can be used by reacting with a polyol, a polyamide, a polycarboxylic acid or the like so as to have a terminal active hydrogen.

(3) Alcohol-modified polysiloxane compound

[0014]

[0015]

(4) Mercapto-modified polysiloxane compound

[0017] (5) Carboxyl-modified polysiloxane compound

[0018]

The polysiloxane compounds having a reactive organic functional group listed above are examples of preferred compounds used in the present invention, and the present invention is not limited to these examples. Therefore, not only the above-exemplified compounds but also other compounds which are currently commercially available and can be easily obtained from the market can be used in the present invention.

Examples of the silane coupling agent having a reactive organic functional group used in the present invention include the following compounds. (1) A silane coupling agent having at least one free isocyanate group.

[0021]

(R ¹ is a lower alkyl group, R ² is a lower alkyl group or a lower alkoxy group, X is a divalent organic group, and a C ₀ -C ₅₀ aliphatic, aromatic or aliphatic fragrance is preferred. These groups may be those having an atom such as O, N, or S as a linking group therein.
Further, m is an integer of 0 to 3, and n is 3-m) Specific preferred examples of the silane coupling agent having a free isocyanate group are as follows.

[0022]

(2) As the silane coupling agent having a reactive organic functional group other than the free isocyanate group,
The following general formula is mentioned.

(Y is, for example, an amino group, an epoxy group,
A group capable of reacting with an isocyanate group such as a hydroxyl group and a thiol group, and particularly preferably an amino group, a thiol group and a hydroxyl group. R ¹ , R ² , X, m and n are as defined above. ) Preferred specific examples of the silane coupling agent having the reactive organic functional group are as follows.

[0025]

The silane coupling agents listed above are examples of preferred compounds used in the present invention.
The present invention is not limited to these examples. Therefore, not only the above-exemplified compounds but also other compounds which are currently commercially available and can be easily obtained from the market can be used in the present invention.

As the organic polyisocyanate to be reacted with the above-mentioned polysiloxane compound and the above-mentioned silane coupling agent used in the present invention, any conventionally known organic polyisocyanate can be used. For example, preferred is toluene-2. , 4-diisocyanate 4-methoxy-1,3-phenylene diisocyanate 4-isopropyl-1,3-phenylene diisocyanate 4-chloro-1,3-phenylene diisocyanate 4-butoxy-1,3-phenylene diisocyanate 2,4-diisocyanate- Diphenyl ether Methylene diisocyanate 4,4-Methylene bis (phenyl isocyanate) Durylene diisocyanate

1,5-naphthalene diisocyanate benzidine diisocyanate o-nitrobenzidine diisocyanate 4,4-diisocyanate dibenzyl 1,4-tetramethylene diisocyanate 1,6-tetramethylene diisocyanate 1,10-decamethylene diisocyanate 1,4-cyclohexylene Diisocyanate xylylene diisocyanate 4,4-methylene bis (cyclohexyl isocyanate) 1,5-tetrahydronaphthalene diisocyanate and the like can be mentioned.

Further, adducts of these organic polyisocyanates with other compounds, for example, those having the following structural formulas can be mentioned, but the adducts are not limited to these.

[0030]

[0031]

[0032]

[0033]

[0034]

[0035] Further, urethane prepolymers and the like obtained by reacting these organic polyisocyanates with low molecular weight polyols and polyamines to form terminal isocyanates can naturally be used in the present invention.

The reaction product used in the present invention is obtained by reacting a polysiloxane compound having an organic functional group as described above, a silane coupling agent having a reactive organic functional group and an organic polyisocyanate as described above. Of an organic functional organic group and an isocyanate group in an equivalent ratio such that a free isocyanate group does not remain, in the presence or absence of a usual urethane catalyst in the absence or presence of an ordinary urethane catalyst, about 0 to 150 ° C.,
Preferably, it can be easily obtained by reacting at a temperature of 20 to 80 ° C. for about 10 to 4 hours.

The reaction product used in the release treatment agent of the present invention can be used alone, but in order to improve the coating suitability for a substrate sheet and the like, the film forming property, etc., various conventionally known products can be used. It is also possible to use a mixture of resins.

Examples of these resins include acrylic resins, polyurethane resins, polyester resins, polybutadiene resins, silicone resins, melamine resins, phenol resins,
Polyvinyl chloride resin, cellulose resin, epoxy resin,
Polyvinyl butyral resin, alkyd resin, modified cellulose resin, fluororesin or polyamide resin can be used. Also, resins obtained by modifying various resins with silicone or fluorine can be used. When these various resins are used in combination, the amount used is 0.1% by weight to 100% by weight in terms of solid content ratio with respect to the above reaction product.

The release treatment agent of the present invention is brought into contact with moisture, water, steam or the like in the air, whereby the hydrolyzable silyl group in the reaction product undergoes a crosslinking reaction to be cured, and at the same time the free isocyanate is released. Since it also reacts and cures, no special heating device or heat treatment for curing is required.

In the present invention, in order to accelerate the silanol condensation, it is preferable to add a catalyst to the stripping treatment agent. Such catalysts are generally alkyl titanates,
Carboxylates such as tin octylate, dibutyltin dilaurate and the like, amino salts such as dibutylamine-2-ethylhexoate and other acidic and basic catalysts are preferred. The amount used is preferably in the range of 0.0001% by weight to 10% by weight of the reaction product of the present invention.

Further, some free isocyanate groups and silyl groups improve the adhesiveness of the release treatment agent layer to the base material sheet by interaction with the surface of the base material sheet, and at the same time, the polyisocyanate in the reaction product. Since the siloxane portion is oriented on the surface, the present invention can provide a releasable treatment agent layer having excellent performance.

[0042]

EXAMPLES Next, the present invention will be described more specifically with reference to Reference Examples, Examples and Comparative Examples. In addition, "part" or "%"
Unless otherwise specified, the weight is based on the weight.

Reference Example 1 Addition product of hexamethylene diisocyanate and water [Duranate 24A-100, manufactured by Asahi Kasei Corporation, NCO% =
23.5%] 150 parts and ethyl acetate 100 parts at 80 ° C.
While stirring well, polydimethylsiloxane with a terminal hydroxyl group having the above structure (molecular weight 2,200)
12 parts was gradually dropped and reacted for 4 hours. Then 40
The mixture was cooled to 0 ° C., and 123 parts of 3-aminopropyltriethoxysilane was gradually added dropwise to the reaction mixture while stirring well to obtain a reaction product (1).

According to the infrared absorption spectrum of the obtained reaction product (1), absorption by free isocyanate groups was not observed at 2,270 cm ⁻¹ , and 1,090 cm
^-1 showed an absorption band based on a -SiO- group. Finally, ethyl acetate was added to obtain a resin solution (A) of Reference Example having a solid content of 50%.

Reference Example 2

Adduct of 1 mol of trimethylolpropane and 3 mol of toluene-2,4-diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., NCO% = 13.0)
%, Solid content 75%) and 100 parts of ethyl acetate are well stirred at 80 ° C., while polydimethylsiloxane having a hydroxyl group at both terminals (molecular weight 3,
Then, 12 parts of 200) was gradually dropped and reacted. Then 4
After cooling to 0 ° C. and stirring well, 77 parts of N-phenyl-γ-aminopropyltriethoxysilane was gradually added dropwise thereto to cause a reaction to obtain a reaction product (2).

According to the infrared absorption spectrum of the obtained reaction product (2), no absorption due to a free isocyanate group was observed at 2,270 cm ⁻¹ , and 1,090 cm was obtained.
^-1 showed an absorption band based on a -SiO- group. Finally, ethyl acetate was added to obtain a resin solution (B) of Reference Example having a solid content of 50%.

Reference Example 3

Hexamethylene diisocyanate trimer (Coronate EH, Nippon Polyurethane Co., NCO% =
21.3%) 150 parts and ethyl acetate 100 parts at 80 ° C
10 parts of polydimethylsiloxane (molecular weight 2,200) having the structure of Reference Example 1 was gradually added dropwise to the reaction mixture while stirring well.

Then, 7 parts of polydimethylsiloxane having an amino group having the above structure (molecular weight of 1,800) having the above structure was gradually added dropwise at 50 ° C. with good stirring, and then 97 parts of γ-mercaptopropyltrimethoxysilane was gradually added. The reaction product (3) was obtained.

According to the infrared absorption spectrum, the reaction product (3) thus obtained showed no absorption by free isocyanate groups at 2,270 cm ^-1 , and also had 1,090 cm.
^-1 showed an absorption band based on a -SiO- group. Finally, ethyl acetate was added to obtain a resin solution (C) of Reference Example having a solid content of 50%.

Example 1 100 parts of the resin solution (A) of Reference Example 1, 300 parts of methyl ethyl ketone, 0.5 part of water and 0.01 part of tin octylate were blended and stirred well, and the release treatment agent of the present invention was mixed. Got

Example 2 100 parts of the resin solution (A) of Reference Example 1, 20 parts of nitrocellulose resin [solid content 20%, manufactured by Daicel Chemical Industries, Ltd.],
312 parts of methyl ethyl ketone, 0.5 part of water and 0.01 part of tin octylate were mixed and well stirred to obtain a release treatment agent of the present invention.

Example 3 100 parts of the resin solution (B) of Reference Example 2, 300 parts of methyl ethyl ketone, 0.5 part of water and 0.01 part of tin octylate were blended and stirred well, and the release treatment agent of the present invention was mixed. Got

Example 4 100 parts of the resin solution (B) of Reference Example 2, 15 parts of a silicone-polyurethane resin [solid content 20%, manufactured by Dainichiseika Kogyo KK (Dialomer)], methyl ethyl ketone 309
Parts, water 0.5 parts and tin octylate 0.01 parts,
The mixture was thoroughly stirred to obtain the release treatment agent of the present invention.

Example 5 100 parts of the resin solution (C) of Reference Example 3, 300 parts of methyl ethyl ketone, 0.5 part of water and 0.01 part of tin octylate were blended and stirred well, and the release treatment agent of the present invention was mixed. Got

Example 6 100 parts of the resin solution (C) of Reference Example 3, polyvinyl butyral resin [solid content 20%, manufactured by Sekisui Chemical Co., Ltd.] 10
Parts, 306 parts of methyl ethyl ketone, 0.5 parts of water and 0.01 parts of tin octylate were mixed and well stirred to obtain a release treatment agent of the present invention.

Comparative Example 1 150 parts of polybutylene adipate (molecular weight 2,000) and 15 parts of 1,3-butanediol were dissolved in 200 parts of methyl ethyl ketone and 50 parts of toluene, and stirred at 60 ° C. with good stirring. 6 parts of methyl ethyl ketone
What melt | dissolved 2 parts of water-added MDI was gradually dripped, and after completion | finish of dripping, it was made to react at 80 degreeC for 6 hours. The solution had a solid content of 35% and a viscosity of 24,000 cps (20 ° C.). Furthermore, 100 parts of the resin solution, silicone oil [SH-200, Toray Dow Corning Co., Ltd.
[Preparation] A compounding liquid consisting of 3 parts and 300 parts of methyl ethyl ketone was used as a peeling treatment agent for a comparative test.

Comparative Example 2 100 parts of the same resin solution as in Comparative Example 1, 5 parts of Teflon powder [manufactured by Daikin Industries, Ltd.] and 345 parts of methyl ethyl ketone / toluene (= 1/1) were mixed to prepare a compounding solution. Isocyanate (solid content 75%, manufactured by Nippon Polyurethane Co., Ltd.) was added to the above-mentioned compounded resin solution: Isocyanate = 24:
3 (weight ratio) was added to provide a peeling treatment agent for comparative tests.

Comparative Example 3 Silicone resin [KS-84 manufactured by Shin-Etsu Chemical Co., Ltd.]
1] Toluene 1, 100 parts and catalyst (PL-7) 1 part
Dissolved in 000 parts, it was used as a silicone resin release treatment agent for comparative tests.

Evaluation Using the release treatment agents of Examples 1 to 6 and Comparative Examples 1 to 3, a 100% modulus of 60 Kg / cm ² and a thickness of 50 μm were used.
m of polyvinyl chloride film was evenly applied so that the thickness when dried was 0.1 μm, and the solvent was evaporated in a drier to prepare a sample having a release agent layer.
When the temperature was 100 ° C. or higher, the polyvinyl chloride film could not maintain its shape as a softened film. The sample was left for 2 days at room temperature (23 ° C., humidity 46%) and then subjected to each test. 20 mm wide on the coated substrate prepared in this way
Acrylic adhesive tape [manufactured by Sekisui Chemical Co., Ltd.] is pressed by a rubber roller having a weight of 2 kg, at room temperature (23 ° C, humidity 46%) for 1 day and at high temperature (40 ° C, humidity 90% or more) for 3 days. After each standing, each sample was measured for peeling force, residual adhesive force, residual adhesive force retention rate, and detachability of the peelable coating layer, and the results are shown in Table 1.

Peeling force : An adhesive tape having a width of 20 mm was attached to the peelable coating layer, stored at 40 ° C. for 20 hours under a load of 20 g / cm ² , and then 180 at a speed of 300 mm / min.
The force (g) required for pulling and peeling at an angle of ° was measured (20 ° C). Residual adhesive strength : The adhesive tape after the peelability measurement was adhered to a stainless steel plate # 280, reciprocated once with a 2 kg tape roller, and after 30 minutes, pulled at an angle of 180 ° at a speed of 300 mm / min to peel. The force (g) required for the measurement was measured (20 ° C.). Residual adhesive strength retention rate : Indicates the% of the residual adhesive strength when a clean adhesive tape not subjected to the above test is adhered to the stainless steel plate # 280 and the adhesive strength (320 g / 20 mm) to the stainless steel plate is set to 100%. ing. Detachability : The strippable film layer is subjected to a reciprocal test with a gauze being reciprocated once with a load of 50 g / cm ^{2 on} the strippable film layer, and a detachment test of the strippable film layer is performed.

[0063]

[Table 1] A: After 1 day at room temperature (23 ° C., 46% humidity) B: After 3 days at high temperature (40 ° C., 90% or more humidity) * 1: The peelable treatment agent layer was destroyed.

[0064]

According to the present invention as described above, the releasable treatment agent layer is formed of a reaction product of a polysiloxane compound having a reactive organic functional group, a silane coupling agent having a reactive organic functional group, and an organic polyisocyanate. By forming it from a resin that does not have a free isocyanate group and has a hydrolyzable silyl group, the peeling force is weak, the residual adhesive force retention rate is high, and the performance is excellent in adhesion to the base material. Is obtained. Further, since the release agent treating layer has a hydrolyzed silyl group, the release agent treating layer is crosslinked by moisture or moisture in the air, so that a one-component curable release agent treating layer can be easily formed. To be done.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location C08G 18/65 NES C09K 3/00 R D21H 19/32 27/00 (72) Inventor Katsumi Kuriyama Tokyo 1-7-6 Nihonbashi-Bakurocho, Chuo-ku, Tokyo Dainichi Seika Chemical Industry Co., Ltd.

Claims (3)

[Claims] 1. A peeling treatment agent containing a resin having a siloxane segment, wherein the resin comprises a polysiloxane compound having a reactive organic functional group, a silane coupling agent having a reactive organic functional group, and an organic polyisocyanate. A releasable treating agent, which is a reaction product and is made of a resin having a hydrolyzable silyl group without having a free isocyanate group. 2. The peeling treatment agent according to claim 1, further comprising another resin. 3. The peeling treatment agent according to claim 1, further comprising water as a curing agent.