JPH06172721A - Tape for fixing abrasive material - Google Patents

Abstract

PURPOSE:To obtain a double-sided adhesive tape which has an adhesive layer extremely tenaciously adhering to an abrasive material and never peeling off therefrom even with heating and pressing in the presence of an abrasive grain liquid and is easily releasable from the platen of a polishing machine after use. CONSTITUTION:This tape for fixing is a double-sided adhesive tape comprising a plastic film substrate, a (pressure-sensitive) adhesive layer (a) which is formed on one side of the substrate and consists mainly of an acrylic polymer, a heat- activable adhesive layer (b) which is formed on the layer (a), tenaciously adheres to an abrasive material and comprises a polyester or polyurethane, and a releasable pressure-sensitive adhesive layer formed on the other side of the substrate. The layer (b) is bonded to an abrasive material before use by hot pressing or by laminating with a heated roll.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape for fixing an abrasive used for polishing such as lapping and polishing of lenses, glass, aluminum disks and wafers.

[0002]

2. Description of the Related Art Conventionally, lenses, glass, aluminum discs,
As a material for polishing wafers, hard urethane foam or synthetic leather with fine pores is used as an abrasive, which is fixed to the surface plate of the polishing machine with a solution type rubber adhesive and used. There is. But with this method,
The adhesive must be applied to the back of the urethane foam or synthetic leather and the surface plate, and the solvent must be dried before bonding.
There is a problem that the process takes time, and when the abrasive is worn and replaced, the adhesive remains on the surface plate side when the abrasive is peeled off, and it takes a lot of time and effort to remove it. . In addition, instead of this, the method of using double-sided tape has begun to be studied.For such tape, an adhesive mainly composed of an acrylic acid ester polymer on a polyester film, styrene isoprene styrene or styrene butadiene styrene, styrene ethylene butadiene styrene Some of them are provided with a rubber-based hot-melt type pressure-sensitive adhesive layer called a block polymer.

[0003]

However, since the abrasive material is porous polyurethane, synthetic leather, or the like, and the surface thereof is porous, these conventionally used pressure-sensitive adhesives cannot be applied to the abrasive material. Adhesiveness is not sufficient, and in polishing glass, lenses, wafers, etc., the stress, pressure and temperature of the rotation of the surface plate of the polishing machine due to the polishing abrasive in the presence of a strong alkali reaching pH 9 to 13,
Since it adheres to the abrasive and the adhesive or double-sided adhesive tape that adheres it, the pads and synthetic leather peel off from the tape during rotary polishing, causing problems such as damage to the workpiece, surface plate, and other parts being polished. There wasn't. Such troubles lead to extremely large losses in the precision polishing process using expensive materials such as workpieces and carriers, and solving this problem has been a major problem for many years. As an improvement of such a problem, the actual exploitation Sho 62-1
Although a pressure-sensitive adhesive as described in Japanese Patent No. 53057 has been proposed, it is found to be effective for a specific abrasive, but it is difficult to apply it to a wide range of abrasives, and further alkali resistance is required to have further characteristics. Was there.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to provide an adhesive layer which firmly adheres an abrasive as described above and does not peel off even when heated and pressed in the presence of an acid / alkaline polishing abrasive. Another object of the present invention is to provide a double-sided adhesive tape which has strong adhesion to an abrasive and can be re-peeled from a surface plate.

[0005]

The present invention provides a double-sided adhesive tape having a strong adhesion capable of preventing peeling from an abrasive, which comprises an acrylic ester polymer as a main component on one side of a plastic film support. A layer made of a pressure-sensitive adhesive or an adhesive is provided, and a heat-activatable adhesive layer made of polyester and / or polyurethane is provided on this layer, and the heat-activatable adhesive layer serves as a laminating surface with an abrasive,
The present invention relates to a double-sided adhesive tape for fixing abrasives, which comprises a re-peelable pressure-sensitive adhesive layer provided on the other surface of a plastic film support. In use, the heat activated adhesive surface is adhered to the abrasive by heat pressing or heat lamination. A pressure-sensitive adhesive or adhesive containing an acrylic polymer as the main component is provided on the surface of the plastic film, so that it is difficult to peel off from the film surface even in the presence of a strong alkaline solution in the polishing process, and exerts a great effect in improving durability. . The plastic film is used for preventing the permeation of the abrasive grain liquid into the adhesive layer, smoothing the adhesive layer and re-peeling after use. Hereinafter, the present invention will be described in detail. The acrylic polymer used in the present invention is a homopolymer of an acrylic acid ester represented by the general formula (Formula I), or one or more acrylic acid ester represented by the general formula (Formula I) and a monomer other than the acrylic acid ester. It is composed mainly of a copolymer composed of a monomer and a monomer. However, in the general formula (Formula I), R ¹ represents hydrogen or a methyl group, and R ² represents an alkyl group having 2 to 14 carbon atoms. In addition, the hard monomers for forming the above-mentioned copolymer composition include the following: vinyl acetate, styrene, maleic anhydride, (meth) acrylic acid, acrylamide, 2-hydroxyethyl (meth) acrylate. , 2-hydroxypropyl (meth) acrylate, acrylonitrile and the like. A polymer obtained by polymerizing these by a conventional method, and a phenol resin, a terpene resin, a styrene resin, a xylene resin, a rosin resin,
A tackifier resin such as a vinyl chloride resin or a petroleum resin is used with or without addition, and a polyisocyanate, a melamine resin, an epoxy resin or the like as a cross-linking agent is appropriately added and mixed with this composition. Since the second layer is further provided with a third layer on top of this, there is no need for many restrictions on the composition and composition of the adhesive or the adhesive as long as it is an adhesive or an adhesive having an intrinsic adhesive property. Acrylic polymers are preferred for this because they should not easily peel off the surface of the film support when exposed to the slurry. The polyester or polyurethane heat-activatable adhesive used in the third layer can have various compositions depending on the combination of the polyhydric alcohol, the polycarboxylic acid, and the isocyanate component used. The polyester in the present invention is synthesized by an esterification reaction or transesterification of a polyhydric alcohol with a polyhydric carboxylic acid or its lower alkyl ester or anhydride with a polyhydric alcohol. As the polyhydric alcohol, ethylene glycol, diethylene glycol, propylene glycol,
Dipropylene glycol, trimethylene glycol,
1,4 butanediol, 1,5 bentanediol, 1,
6-hexanediol, 1,4-cyclohexanediol,
One or more of neopentyl glycol, glycerin, trimethylolpropane, etc., or alkylene oxide adducts thereof, and polycarboxylic acid, malonic acid, maleic acid, terephthalic acid, isophthalic acid, orthophthalic acid, 2, 6 naphthalene dicarboxylic acid,
Aromatic dicarboxylic acids such as paraphenylenedicarboxylic acid,
A polyester polyol which is one or a combination of succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, trimellitic acid, 1,4 cyclohexanedicarboxylic acid and the like, or ε-caprolactone, propiolactone, a polyol obtained by ring-opening polymerization of a cyclic ester such as β-methyl-δ-valerolactone, further the polyol,
Polyester polyols from three kinds of polyvalent carboxylic acids and cyclic esters can also be used. Since it is used as a heat-activatable adhesive composition, it preferably has a low glass transition point and has an average molecular weight of 2,000 to 100,000.
0, more preferably 5,000 to 30,000,
The glass transition point is −60 ° C. to 70 ° C., more preferably −4.
It is in the range of 0 ° C to 50 ° C. Polyurethane adhesive is
Polyester polyol consisting of the above polyhydric alcohol and polyhydric carboxylic acid, or polycaprolactone polyester polyol, or a polyester polyol having the above both in the main chain, or polyethylene glycol,
Polyoxypropylene glycol, polytetramethylene ether glycol, polyether polyol such as ethylene oxide / propylene oxide copolymer, or polycarbonate polyol, various polyols such as castor oil, and those obtained by the reaction of an isocyanate compound. Is an aromatic diisocyanate such as diphenylmethane diisocyanate, 2,4 tolylene diisocyanate, 2,6 tolylene diisocyanate, phenylene diisocyanate, 1,5 naphthylene diisocyanate, xylylene diisocyanate, toluylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, Aliphatic such as 4,4'dicyclohexylmethane diisocyanate, or Examples thereof include alicyclic diisocyanates. In addition, a low molecular weight compound having active hydrogen in the molecule is generally used as a chain extender in the polyurethane synthesis step. In the present invention, these ethylene glycol, butanediol, propylene glycol, 1,
6-hexanediol, diol such as xylene glycol, water, ethylenediamine, isophoronediamine, phenylenediamine, tolylenediamine, hydrazine, piperazine and the like can be used alone or in combination of two or more. Various polyols to be reacted with the isocyanate preferably have an average molecular weight of about 300 to 5,000, and it is preferable to design the total amount of the polyol and the chain extender to be 1 to 2 mol per 1 mol of the isocyanate. To synthesize urethane, prepare a solution of toluene, methyl ethyl ketone, acetone, ethyl acetate, cyclohexane, dioxane, methyl cellosolve acetate, etc., so that the concentration of the reaction product is 35% or more, and heat the addition reaction in a nitrogen stream to complete the reaction. Dilute later. The average molecular weight of the thus obtained polyurethane as a heat-activatable adhesive is 6,000 to 200,000, more preferably 8,000 to 100,000, and the glass transition point is -60 ° C to 70 ° C. , More preferably -40 ° C
It is in the range of -60 ° C. As heat-activatable adhesives, these polyesters, active hydroxyls such as hydroxyl groups at the ends of polyurethanes, carboxylic acids, etc., and trifunctional or higher functional isocyanates are reacted very slightly and partially cured to produce heat resistance after heat-activatable adhesion. It is also possible to improve durability and the like. The re-peelable adhesive used for the first layer always holds the abrasive against strong shearing force during the polishing process, and when the abrasive is worn and needs to be replaced, the tape together with the polishing plate of the polishing machine can be used. Since it is peeled off, it is required that there is no adhesive residue. As the adhesive, natural rubber,
Adhesives such as polyisobutylene, styrenic block polymers, acrylic acid ester polymers are preferred. The material used for the tape support is required to be a plastic film because it is smooth by itself and requires a certain level of strength so that it will not break when re-peeling and leave no adhesive residue on the platen. The plastic film is generally polyester, polyethylene, CPP, OPP, polyvinyl chloride, or the like, but is not limited thereto. The plastic film does not have to be a single layer, and may be a multilayer laminate film of two or more kinds of plastics or metal foils. The thickness of the support made of these films is preferably about 20 to 200 μm. The method for producing an adhesive tape of the present invention comprises producing a double-sided tape by a conventional method, and thereafter,
It is preferable to coat three layers on top of the layers. The production of the double-sided tape is not particularly limited, and any method such as directly applying each adhesive or pressure-sensitive adhesive to the film surface with a knife, reverse, gravure or the like, or applying it to release paper and transferring it to the film Is possible. After reapplying the peeling adhesive on one side of the film in this way, drying and applying the adhesive or adhesive on the other side, protecting with double-sided release paper, and winding to form a tape, Apply another polyester or polyurethane adhesive solution on another release paper and dry it.Make this adhesive surface and the adhesive or adhesive surface the same, and transfer the polyester or polyurethane adhesive film by normal temperature or heat roll lamination. It is manufactured by, but it is not particularly limited to this method,
A method in which a polyester adhesive is applied as a hot melt type by extrusion coating and then laminated may be used. The double-sided adhesive tape for fixing abrasives obtained in this way is used for lapping of abrasive sheets for polishing such as commercially available synthetic leather suede and velour, and hard urethane foam containing abrasive grains such as cerium oxide. It is heat-bonded to the abrasive sheet. The heat-activatable adhesive layer is temporarily attached to the back surface of the abrasive sheet, or to either surface of the abrasive sheet if there is no front and back surfaces, and adhesion is carried out by hot pressing or roll laminating. In the case of about 90 ° C. or higher, the deformation and strain tend to increase and the influence on the object to be polished tends to increase, so it is desirable to perform the bonding temperature below this.

[0006]

EXAMPLES Examples will be given below to more specifically show the present invention. Preparation of acrylic polymer composition 800 parts of ethyl acetate (all parts represent parts by weight),
A monomer mixture having the following composition was charged into a four-necked flask with stirring, heated to 80 ° C. for 8 hours under reflux, and then 0.5 part of hydroquinone was added to stop the reaction. Butyl acrylate 680 parts Vinyl acetate 240 parts Acrylic acid 80 parts 2-Hydroxypropyl acrylate 3 parts Azobis isobutyronitrile 1 part Ethyl acetate 700 parts was added to the obtained polymer and diluted to give a solution of the polymer. 3500 cps, solid content 3
It was 8.5%. (Composition A)

[0007]

Example 1 To 100 parts of composition A, 10 parts of super ester A115 (disproportionated rosin ester manufactured by Arakawa Chemical Co., Ltd., softening point 115 ° C.) was added, mixed and dissolved, and Coronate L0.5 was added thereto. Parts were added and well stirred to give an adhesive. This pressure-sensitive adhesive was directly applied on Emblet S-25 (polyester film manufactured by Unitika Ltd., 25 μ) so as to have a dry thickness of 70 μ, and dried to form a coating film. A monomer mixture having the following composition as a heat-activatable adhesive was charged into a flask while stirring, and a condensation reaction was carried out at 250 ° C. for 2 hours under reduced pressure. Terephthalic acid 160 parts Adipic acid 120 parts 1,6 Hexanediol 200 parts Polycaprolactone diol 50 parts The obtained polyester was a polymer having an average molecular weight of 14,000. (Composition B) Composition B was dissolved in toluene to obtain a solution having a solid content of 25%. This was applied uniformly on an OPP film and dried to a dry thickness of 20 μm, and the adhesive surface and the above-mentioned adhesive surface were put together to form a heat-activatable adhesive layer on the adhesive. Next, 1 of Composition A
Coronate L (Japan Polyurethanes Co., Ltd.)
2.0 parts of polyisocyanate) was added and mixed well to obtain a re-peeling pressure-sensitive adhesive. This re-release type adhesive
Dry thickness 4 on release paper coated with silicone release agent
It was coated and dried so as to have a thickness of 5 .mu.m, laminated on the other side of the Embrette S-25 at room temperature, and transferred to obtain a tape.

[0008]

Example 2 1 part of Hitanol was added to 100 parts of the composition A.
502F (phenolic resin manufactured by Hitachi Chemical Co., Ltd., softening point 97 ° C.) 5 parts, 140 × 100 (vinyl chloride resin manufactured by Nippon Zeon Co., Ltd.) 5 parts, Tespol 1072 (modified chemical rosin manufactured by Hitachi Chemical Polymer Co., Ltd.) Ester resin, softening point 1
(10 ° C.) 7 parts were mixed and dissolved, and 3.0 parts of melan 28 (melamine resin manufactured by Hitachi Chemical Co., Ltd.) was added and well stirred. This adhesive is Sumilite VSS6701 (Sumitomo Bakelite Co., Ltd. vinyl chloride film, 50μ)
Was directly applied onto the above so as to have a dry thickness of 40 μm, and dried to form a coating film. As a heat-activatable adhesive, a monomer mixture having the following composition was charged into a flask while stirring, and the mixture was heated to 120 ° C for 3
The condensation reaction was carried out at 190 ° C. for 18 hours under reduced pressure. Sebacic acid 200 parts Adipic acid 70 parts Dipropylene glycol 150 parts 1,4 Butanediol 60 parts To 300 parts of the obtained polyester polyol, 20 parts of diethylene glycol, 5 parts of tolylene diisocyanate
Charge 0 part and 500 parts of toluene into a flask, and keep the temperature at 120 ° C.
After reacting for 1 hour, 650 parts of methyl ethyl ketone was added to obtain a polyurethane heat activated adhesive having a solid content of 24%. (Composition D) This was directly applied onto the acrylic adhesive surface and dried to make the heat-activatable adhesive layer have a dry thickness of 40 μm, and a layer of 80 μm was formed together with the adhesive agent layer.
In addition, Example 1 is provided on the other surface of the Sumilite VSS6701.
A releasable pressure-sensitive adhesive layer was formed in the same manner as in 1. to prepare a double-sided adhesive tape.

[0009]

Comparative Example 1 The tape excluding the heat activated adhesive layer of Example 1 was used as Comparative Example 1.

[0010]

Comparative Example 2 The tape excluding the heat-activatable adhesive layer of Example 2 was used as Comparative Example 2. The abrasive-bonded surface of each of the above double-sided adhesive tapes using a heat-activatable adhesive is bonded to a hard urethane foam abrasive LP pad LP77 (James H
・ Rhodes Co., 1.0mm thickness), 80 ℃ 2Kg / c
^They were bonded by thermocompression bonding for 20 seconds under m ² . The re-peeling adhesive surface was protected with a release paper. Similarly, a hard urethane foam abrasive KSP66 (Kuju Electric Co., Ltd., 1.2)
(mm thickness) by thermocompression bonding at 85 ° C. and 2 Kg / cm ² for 30 seconds,
Glued These adhesion test pieces are 25 mm wide and 250 mm long.
Cut to mm, peel off the release paper, and re-peeling the adhesive surface cold rolled steel plate JIS G3 with a width of 30 mm and a length of 125 mm.
It stuck on SPCC-SD of 141 regulation, and pressure-bonded with the rubber roller of 2 kg. After laminating, leave it at room temperature for 1 day, forcibly peel off the double-sided adhesive tape from the laminating surface of the abrasive,
The 180 degree peel adhesion strength was measured. In addition, the above-mentioned laminated test piece was prepared by polishing with a polishing abrasive grain liquid cerium oxide fine powder (Rocks; manufactured by Tohoku Metal Chemical Co., Ltd.) potassium hydroxide at a pH of 20 to prepare a 20% aqueous solution at 50 ° C.
It was immersed in the solution which had been heated, and left for 5 days. After taking it out, the 180 ° peel adhesion strength was measured immediately at room temperature.

[0011]

[Table 1] Destruction symbol: A Interface peeling of the tape from the abrasive material S Interface peeling of the polyester or polyurethane layer and the adhesive layer B B Urethane pad material destruction

[0012]

[Effect] Since the double-sided adhesive tape of the present invention is adhered to various abrasives by using polyester or polyurethane heat activated adhesive, it can be adhered at a relatively low temperature, and particularly the adhesive force to the urethane pad. It is excellent in adhesiveness and does not peel off the adhesive from the film support surface of the tape, and after being adhered to the surface plate, it is adhered to the object to be polished and the carrier material,
Even when subjected to the stress of rotating and rocking at high speed and frictional heat for a long time while flowing the polishing abrasive liquid, the tape does not peel off from the polishing material, and excellent adhesiveness can be maintained.

[0013]

[Chemical 1]

Claims (1)

[Claims] 1. A plastic film support is provided on one side thereof with a layer made of a pressure-sensitive adhesive or an adhesive containing an acrylic polymer as a main component, and a heat-activatable adhesive made of polyester and / or polyurethane is provided on the pressure-sensitive adhesive or the adhesive. An adhesive layer is provided, the heat-activatable adhesive layer serves as a surface for laminating with an abrasive, and a re-releasing pressure-sensitive adhesive layer is provided on the other surface of the plastic support for fixing abrasives. Adhesive tape.