JP2002285114A - Tape for abrasive fixing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a double-coated tape for abrasive fixing which is readily capable of positioning, has an adhesive force not reducing from a low temperature to a high temperature, does not fall abrasives during polishing and from which the abrasives can be peeled by a proper force after polishing, when the abrasives are adhered to a polishing plate. SOLUTION: This tape for abrasive fixing is obtained by providing both sides of a substrate with acrylic adhesive layers comprising 100 pts.wt. of an acrylic polymer and >=10 pts.wt. and <=35 pts.wt. of a tackifier resin (preferably polymerized rosin ester) which has >=100 deg.C (preferably >=120 deg.C) and <=170 deg.C softening point and is incompatible with the acrylic polymer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape used for fixing a polishing material when polishing a material to be polished such as a semiconductor wafer, an integrated circuit (IC), a glass for a liquid crystal, a hard disk, and a lens.

[0002]

2. Description of the Related Art The abrasive used for polishing the above-mentioned material to be polished is usually used in the form of a polishing cloth or a polishing pad. This is fixed to a polishing plate made of metal or ceramic of a polishing apparatus, and a semiconductor wafer, an integrated circuit (IC), a glass for liquid crystal, a hard disk, a lens, and the like as a material to be polished are fixed to the opposing polishing plate. . Then, the abrasive and the material to be polished are pressed in the presence of the slurry liquid, and the polishing platen is rotated to polish the material to be polished.

Generally, a double-sided tape having an adhesive formed on both sides of a base material is used to fix the abrasive to the polishing platen. The bonding between the abrasive and the double-sided tape is performed by polishing the abrasive with the double-sided tape during polishing. Since it is required not to peel between the tapes, a strong adhesive is used as the adhesive for bonding the abrasive. On the other hand, the required quality of the adhesive for bonding the polishing platen is that the adhesive does not peel off between the polishing platen and the double-sided tape during polishing, and when the polishing material is peeled off from the polishing platen after polishing is completed, the adhesive residue It is required that the abrasive can be peeled off with an appropriate force without causing the generation of the abrasive.

[0004] Normally, when the polishing material is attached to the polishing surface plate, the operator holds the abrasive material by hand and positions the polishing material on the polishing surface plate before bonding. Therefore, it is desirable that the tack be low for this alignment. In the winter season, the bonding environment is often at a low temperature (0 ° C. to 10 ° C.), and it is necessary that the polishing material and the polishing platen be sufficiently bonded at a low temperature. On the other hand, the temperature may rise to about 50 ° C. during polishing. Therefore, it is necessary that the abrasive does not peel off from the polishing platen during polishing from a low temperature to a high temperature range, and it is necessary that the abrasive can be peeled off with an appropriate force after the polishing is completed. .

[0005] As an adhesive of this double-sided polishing tape,
Conventionally, rubber-based adhesives and acrylic-based adhesives have been used. In particular, in the polishing of the semiconductor wafer and integrated circuit forming process, in order to avoid the influence of the presence of a trace amount of metal, it is desired that the adhesive contains no metal,
In general, a rubber-based pressure-sensitive adhesive is configured to increase the cohesive force of the pressure-sensitive adhesive by mixing a metal as a crosslinking agent or a co-catalyst. For example, JP-A-6-158008 discloses a pressure-sensitive adhesive composition containing a rubber-based elastomer, a phenol resin, and an organometallic compound as a crosslinking catalyst.

On the other hand, acrylic pressure-sensitive adhesives can be cross-linked with isocyanate, epoxy, aziridine, etc., can obtain sufficient cohesion without using metal, and are used for double-sided tapes for abrasives. As an adhesive,
It is desirable to use an acrylic adhesive.

When the operator attaches the polishing material and the polishing platen, positioning is necessary, and therefore, the tack needs to be reduced. In order to meet this demand in an acrylic pressure-sensitive adhesive, it is generally possible to lower the tack by adding a tackifier resin. But,
When the tackifying resin is blended, the tackiness in a low temperature range is reduced. Therefore, hitherto, tackiness has been reduced by blending a tackifying resin in the acrylic pressure-sensitive adhesive to maintain an appropriate adhesive force in a range from a low temperature range to a high temperature range (about 50 ° C.), and after polishing is completed. It has been considered difficult to obtain an abrasive fixing tape having an appropriate removability.

[0008]

SUMMARY OF THE INVENTION In view of the above problems of the conventional double-sided tape for fixing abrasives, the present invention provides a double-sided abrasive fixing double-sided adhesive having an acrylic adhesive which does not particularly require metal. It was made with respect to the tape, the purpose is that when the operator pastes the abrasive on the polishing platen, it is possible to easily adjust the position, the adhesive strength does not decrease from low to high temperatures, Abrasive material does not peel off from the polishing platen during polishing due to sufficient adhesion between the abrasive material and the polishing surface plate, and after the polishing is completed, the abrasive material can be peeled off from the polishing surface plate with an appropriate force. It is to provide a double-sided tape for fixing.

[0009]

In order to achieve the above object, the present invention as defined in claim 1 is directed to an acrylic polymer 100.
Acrylic pressure-sensitive adhesive having a softening point of 100 ° C. or higher and 170 ° C. or lower and 10 to 35 parts by weight of a tackifying resin incompatible with the acrylic polymer, Provided is an abrasive fixing tape provided on both sides of a substrate.

The second aspect of the present invention provides the abrasive fixing tape according to the first aspect, wherein the tackifier resin has a softening point of 120 ° C. or more. According to a third aspect of the present invention, there is provided the abrasive-fixing tape according to the first or second aspect, wherein the tackifying resin is a rosin ester or a rosin-modified phenol.

The acrylic pressure-sensitive adhesive of the present invention contains an acrylic polymer as a main component, and the acrylic polymer mainly contains an alkyl (meth) acrylate having an alkyl group having 2 to 18 carbon atoms. Used as an ingredient,
The ester can be obtained by polymerization or copolymerization using the ester alone or in combination with a monomer copolymerizable therewith. As the polymerization method, known methods such as a bulk polymerization method, a solution polymerization method, an emulsion polymerization method, and a dispersion polymerization method can be employed. Further, the method of initiating the polymerization is not particularly limited, and a method using a thermal polymerization initiator such as benzoyl peroxide, lauroyl peroxide, azobisbutyronitrile, or a photopolymerization initiator such as benzoin, benzoin methyl ether, benzophenone, and ultraviolet irradiation. And a method using electron beam irradiation can be arbitrarily selected. The weight average molecular weight of the obtained (meth) acrylic polymer is preferably 200,000 or more.

(Meth) as the main component of the acrylic polymer
Examples of the alkyl acrylate include ethyl (meth) acrylate, n-propyl (meth) acrylate, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, sec-butyl (meth) acrylate, and t-butyl ( (Meth) acrylate, n-octyl (meth) acrylate, iso-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and glue (meth) acrylate, dodecyl (meth) acrylate, and the like. Alternatively, two or more kinds are used in combination. The alkyl group has 2 to 18 carbon atoms.
If the ratio is out of the range, the properties as an adhesive are impaired, which is not preferable.

Examples of the monomer copolymerizable with the above-mentioned main component include unsaturated acids such as (meth) acrylic acid, itaconic acid, 2- (meth) acrylic acid propanesulfonic acid and (meth) acryloxyethyl phosphate; And polar monomers such as hydroxyl group-containing monomers such as -hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate. These polar monomers are effective as components for increasing the cohesive strength of the pressure-sensitive adhesive. In addition to the above polar monomers, methyl (meth) acrylate, styrene,
A monomer that gives a polymer having a high glass transition point, such as vinyl acetate, (meth) acrylonitrile, and (meth) acrylamide, can also be used.

The tackifying resin used in the present invention has a softening point of 100 ° C. or more and 170 ° C. or less and is incompatible with an acrylic polymer which is a main component of the acrylic pressure-sensitive adhesive. The softening point of the tackifier resin is 100 ° C
If it is less than 170 ° C., the effect of lowering the tack is small, and if it exceeds 170 ° C., the viscosity of the pressure-sensitive adhesive solution increases, which causes a problem in production. The preferred softening point is from 120 ° C to 160 ° C.

When the tackifier resin is incompatible with the acrylic polymer, the acrylic pressure-sensitive adhesive after drying or curing of the solvent becomes cloudy, but has a high initial adhesive strength at a low temperature,
The polishing material does not peel off from the polishing platen during polishing. When the tackifying resin is compatible with the acrylic polymer, transparency is maintained, the initial adhesive strength at a low temperature is low, and the abrasive is easily separated from the polishing platen during polishing.

The acrylic pressure-sensitive adhesive layer of the present invention has a softening point of 10 with respect to 100 parts by weight of the acrylic polymer.
It is composed of an acrylic pressure-sensitive adhesive containing 10 to 35 parts by weight of a tackifying resin having a temperature of 0 ° C. to 170 ° C. and incompatible with an acrylic polymer. The tackifying resin is added in an amount of 1 to 100 parts by weight of the acrylic polymer.
If the amount is less than 0 parts by weight, the tack reduction effect is poor, and if it exceeds 35 parts by weight, the holding power is undesirably reduced.

As the tackifier resin in the present invention, a natural resin type and a synthetic resin type can be used. There are rosin type and terpene type in natural resin type, and petroleum resin type, phenol type, xylene resin, cumarone resin and ketone resin type in synthetic resin type. Examples of the tackifier resin having a softening point of 120 ° C. or higher include a polymerized rosin ester resin, a rosin-modified phenol resin, a coumarone-indene resin, and a xylene resin. When mixed with acrylic adhesive,
Polymerized rosin ester resins are well-balanced resins in the low to high temperature range.

The acrylic pressure-sensitive adhesive may generally contain a crosslinking agent for improving cohesion. The crosslinking agent does not contain a metal, and examples thereof include an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, and an aziridine-based crosslinking agent. The acrylic pressure-sensitive adhesive may contain various conventionally known additives, for example, a plasticizer, a softener, and the like, as necessary.

The tape of the present invention is in the form of a so-called double-sided tape.
A plastic film such as a polypropylene resin, a plastic foam made of a polyurethane resin or a polyolefin resin, or the like can be used. As the material of the nonwoven fabric, rayon, polyester, pulp, hemp, polyethylene, polyurethane or the like is used alone or in combination, and usually used in a range of 5 to 100 g / m ² as a basis weight. Also,
Laminates of these substrates can also be used. The thickness of the pressure-sensitive adhesive layer provided on both surfaces of such a substrate is not particularly limited, and is usually 10 to 100 μm.

The property required for the surface to be bonded between the abrasive and the double-sided tape is that the abrasive and the double-sided tape do not peel off during polishing. This bonding is generally performed using a device such as a laminator. Therefore, the re-peelability, position adjustment, and well-balanced adhesion from a low temperature range to a high temperature range, which are usually required for the bonding surface between the abrasive and the polishing platen, are unnecessary. Therefore, it is required that the acrylic adhesive has strong adhesion.

From the viewpoint of strong adhesion, a hot melt pressure-sensitive adhesive layer may be provided on the surface of the acrylic pressure-sensitive adhesive layer depending on the surface shape and material of the abrasive.

[0022]

EXAMPLES (Example 1) (1) Preparation of acrylic polymer 55 parts by weight of 2-ethylhexyl acrylate, 40 parts by weight of butyl acrylate, 6 parts by weight of acrylic acid, 0.05 part by weight of lauryl mercaptan as a chain transfer agent And 80 parts by weight of ethyl acetate as a solvent were charged to a total of 1 kg in a five-necked flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel and a nitrogen gas inlet, and dissolved by stirring. Purging was performed for 30 minutes to remove oxygen present in the monomer solution. Then, the air in the flask was replaced with nitrogen gas, and the temperature was increased while stirring.
While maintaining the temperature at 0 ° C., 0.03 parts by weight of benzoyl peroxide as a thermal polymerization initiator was dissolved in 3 cc of ethyl acetate, and the solution was added dropwise using a dropping funnel. After the start of the reaction,
The reaction was carried out for 0 hour to obtain an acrylic polymer.

(2) Production of Acrylic Adhesive Tape 3 parts by weight of a polyfunctional isocyanate (trade name: Coronate L, manufactured by Nippon Polyurethane Co.) as a crosslinking agent was added to 100 parts by weight of the solid content of the acrylic polymer solution. Rosin ester resin (trade name: Pencel D-1) as a tackifying resin
35, Arakawa Chemical Co., Ltd., softening point: 135 ° C.) was added in an amount of 25 parts by weight to obtain an acrylic pressure-sensitive adhesive. The obtained acrylic pressure-sensitive adhesive is applied to each of two release papers with a thickness of 3 after drying.
Apply from 5 μm to 45 μm, and then
Dry at a temperature of 00 ° C. for 5 minutes. Next, the pressure-sensitive adhesive composition on the release paper was overlaid with a nonwoven fabric as an intermediate layer, and pressed with a roll to obtain a nonwoven fabric-based double-sided tape.

Comparative Example 1 A double-sided tape using a nonwoven fabric as a base material was obtained in the same manner as in Example 1 except that no tackifying resin was used. (Comparative Example 2) A nonwoven fabric was used as a base material under the same conditions as in Example 1 except that a terpene phenol resin (trade name: YS Polystar S145, Yashara Chemical Co., softening point: 145 ° C) was used as the tackifier resin. A double-sided tape was obtained.

[Evaluation Method] The properties of the tackifying resin used in the above Examples and Comparative Examples, and the physical properties of the obtained double-sided tape were evaluated by the following methods. It is described in Table 1. (1) Softening point Measured by the ring and ball method. (2) Compatibility of tackifying resin with acrylic polymer The sample in which the thickness of the acrylic pressure-sensitive adhesive after drying is 45 μm is incompatible when the turbidity is 10% or more, and compatible when the turbidity is less than 10%. And The turbidity measurement method is JIS K710
NDH-300A (NIPP
ON DENSHOKU) and the following formula. Turbidity (%) = (diffuse transmitted light / total transmitted light) × 100 (3) Tack According to JIS Z0237 based on the Dow method,
The measurement was performed by rolling a steel ball at an inclination angle of 30 degrees and a runway length of 100 mm.

(4) Adhesion to Hard Chrome Plate The hard chrome plate and the tape are allowed to stand at each temperature for one day. At each temperature, apply 25 tapes to the hard chrome plated plate.
mm width and left at each temperature for 20 minutes.
Measure the 0 ° peel strength. The pulling speed is 300mm /
Minutes. (5) Removability At 23 ° C and 65%, tape was applied to a hard chrome plated plate by 25 m
After immersing in warm water of 60 ° C for 3 days,
The removability (adhesive residue) under an environment of 23 ° C. and 65% was evaluated.

[0027]

[Table 1]

[0028]

The tape for fixing abrasives according to the present invention is constructed as described above, and is used to adjust the position when an operator attaches an abrasive such as abrasive paper, a polishing cloth or a polishing pad to a polishing platen. It is possible to easily perform, the adhesive strength does not decrease even in a high temperature range from a low temperature range, the polishing material does not peel off from the polishing platen during polishing by sufficiently bonding the polishing material and the polishing platen, After the polishing is completed, the abrasive can be peeled off from the polishing platen with an appropriate force, and this has a great effect practically.

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Claims (3)

[Claims] 1. An acrylic polymer, based on 100 parts by weight,
An acrylic pressure-sensitive adhesive layer having a softening point of 100 ° C. or more and 170 ° C. or less and containing an incompatible tackifier resin with respect to the acrylic polymer of 10 parts by weight or more and 35 parts or less,
A polishing material fixing tape, which is provided on both surfaces of a base material. 2. The abrasive fixing tape according to claim 1, wherein the tackifier resin has a softening point of 120 ° C. or higher. 3. The abrasive fixing tape according to claim 1, wherein the tackifier resin is a polymerized rosin ester.