JP6225377B2 - Adhesive tape and laminated adhesive tape - Google Patents

Description

  The present invention relates to a pressure-sensitive adhesive tape that can be used for fixing a foam material in various applications including automobile interior materials.

Joining using an adhesive tape is known as a joining means that has excellent adhesion workability and high adhesion reliability. Therefore, the adhesive tape is widely used for fixing various parts in, for example, production scenes of automobiles, electrical products and the like.
For example, in the automotive field, adhesive tape is used to improve the airtightness, watertightness, sound absorption, soundproofing, vibration proofing, etc. For automobiles such as foam materials, car bodies, air conditioning units, ceilings, door trims, seats, etc. It is often used for fixing to parts.
However, since the surface of the foam material usually has an uneven shape due to holes, the contact area at the interface between the adhesive tape and the foam material is small, and as a result, the time at the interface There was a case of causing a flaking.

On the other hand, organic solvent-type pressure-sensitive adhesives have been frequently used for forming the pressure-sensitive adhesive layer constituting the pressure-sensitive adhesive tape. However, in recent years, there has been a demand for an adhesive tape having an adhesive layer formed using a water-dispersed adhesive instead of the organic solvent-based adhesive as demand for environmentally friendly products increases. Yes.
The water-dispersed pressure-sensitive adhesive is, for example, a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed from an aqueous pressure-sensitive adhesive composition, and the pressure-sensitive adhesive composition includes an aqueous solvent and an acrylic polymer dispersed in the aqueous solvent. There is known a pressure-sensitive adhesive sheet having a 180 ° peeling adhesive strength of 1.5 N / 20 mm or more when it is pressure-bonded to a predetermined flexible urethane foam under predetermined conditions (for example, see Patent Document 1). .)

  However, the pressure-sensitive adhesive tape formed using the water-dispersed pressure-sensitive adhesive generally tends to be inferior in terms of adhesive force as compared with a pressure-sensitive adhesive tape formed using an organic solvent-type pressure-sensitive adhesive. In some cases, the adhesiveness to the foam material is not practically one step further.

  By the way, when the adhesive tape is used for fixing the foam material or the like, usually one or two or more of the adhesive tapes attached to one adhesive layer of the adhesive tape are stacked, and stamping is performed. In many cases, a method of cutting into a predetermined shape by a method or the like and then removing the release liner from the surface of the other pressure-sensitive adhesive layer and sticking to a predetermined site is often employed.

  However, when the shape to be cut has an acute cut, etc., when the release liner is removed, the release liner is likely to be broken, and as a result, the workability of the pasting is significantly reduced. was there.

JP2012-97234

  The problem to be solved by the present invention is excellent in adhesiveness to a foam material as an adherend, and it is difficult to cause tearing of the release liner when removing the release liner, and does not cause deterioration in pasting workability. It is providing the adhesive tape which has an adhesive layer formed using an aqueous adhesive composition.

  The present inventors proceeded with studies based on an adhesive tape having an adhesive layer formed using an aqueous adhesive composition used for fixing a foam material, and combined the adhesive tape with a specific release liner. It was found that the above problem can be solved.

That is, this invention is an adhesive tape used for fixation of foam material, Comprising: The said adhesive tape is the adhesive layer (A) formed by using an aqueous adhesive composition on both surfaces of a core base material (A) ( B), and a release liner (C) is laminated on one side or both sides of the pressure-sensitive adhesive layer (B),
The tensile strength in the flow direction of the release liner (C) measured by a tensile test at a speed of 20 m / min is 35 N / 5 mm or more, and the tensile strength in the width direction of the release liner (C) is 35 N / 5 mm or more,
The flow direction bending resistance (Gurley method) of the release liner (C) measured in accordance with JIS L 1085 is 1000 mg or more, and the width release direction bending resistance of the release liner (C). The Gurley method is about 1000 mg or more.

  The pressure-sensitive adhesive tape of the present invention can reduce an environmental load caused by an organic solvent and the like, has excellent adhesiveness even with respect to a foam material having a small contact area, and releases the release liner when it is removed. Since it is possible to prevent the mold liner from being torn and prevent the adhesive workability of adhesive tapes and the like from being lowered, it can be suitably used for fixing a foam material at a predetermined position in, for example, an automobile or an electrical product manufacturing scene. Is possible.

It is sectional drawing of the test piece 7 obtained by sticking ether type urethane foam on the single side | surface of an adhesive tape. It is a top view of the test piece 7 obtained by sticking ether type urethane foam on the single side | surface of an adhesive tape. It is a top view of the test piece 8 obtained by stamping the test piece 7 obtained by sticking ether type urethane foam on one side of the adhesive tape.

  The pressure-sensitive adhesive tape of the present invention has a pressure-sensitive adhesive layer (B) formed using an aqueous pressure-sensitive adhesive composition on both sides of the core substrate (A), and one or both sides of the pressure-sensitive adhesive layer (B). The release liner (C) is laminated with a tensile strength in the flow direction of the release liner (C) measured by a tensile test at a speed of 20 m / min, which is 35 N / 5 mm or more, The release liner (C) has a tensile strength in the width direction of 35 N / 5 mm or more, and the bending flexibility (Gurley method) in the flow direction of the release liner (C) measured in accordance with JIS L 1085 is 1000 mg. Of the above, the release liner (C) is characterized in that the bending resistance (Gurley method) in the width direction is 1000 mg or more, and is exclusively used for fixing a foam material.

[Core substrate (A)]
As a core base material (A) which comprises the adhesive tape of this invention, a nonwoven fabric, a resin film, etc. can be used, for example.

  As the core substrate (A), it is preferable to use one having a thickness of 1 μm to 200 μm.

  As said nonwoven fabric, what is formed using the fiber which consists of rayon, a pulp, a Manila hemp, nylon, polyester, a polypropylene, polyvinyl alcohol etc., for example can be used. Among these, as the non-woven fabric, it is possible to use a non-woven fabric formed using fibers obtained by mixing one or more selected from the group consisting of rayon, pulp and manila hemp. It is preferable to further improve the adhesion to the adhesive), and it is more preferable to use a non-woven fabric formed using fibers obtained by mixing one or more selected from the group consisting of rayon and pulp. It is more preferable to use a nonwoven fabric formed using fibers obtained by mixing rayon and pulp.

  The mixing ratio of the rayon and the pulp is preferably in the range of rayon / pulp (mass ratio) = 2/8 to 8/2 in order to further improve the adhesion with the pressure-sensitive adhesive layer (B). .

  As the non-woven fabric, those subjected to a viscose impregnation treatment, an impregnation treatment with a thermoplastic resin, etc., and a surface treatment as necessary can be used.

As the nonwoven fabric, it is preferable to use a basis weight of ^{5g / m 2 ~25g / m 2} , is possible to use one of ^{8g / m 2 ~16g / m 2} , the adhesive layer (B) It is preferable for further improving the adhesion of the resin.

  As the nonwoven fabric, those having a thickness of 20 μm to 80 μm are preferably used, and those having a thickness of 30 μm to 50 μm are more preferable for further improving the adhesion with the pressure-sensitive adhesive layer (B). .

  Examples of the resin film that can be used for the core substrate (A) include polyethylene terephthalate (hereinafter referred to as PET), triacetyl cellulose, polyacrylate, cellophane, polyethylene, polypropylene, polyvinyl alcohol, polycarbonate, nylon, polysulfone, A film formed using polystyrene, polyimide, aromatic polyimide, or the like can be used. Among these, it is preferable to use a PET film as the resin film in order to obtain a pressure-sensitive adhesive tape that is inexpensive and has high strength and excellent insulating properties.

  As the resin film, it is preferable to use a resin film that has been subjected to an easy adhesion treatment for the purpose of further improving the adhesion to the pressure-sensitive adhesive layer (B). Easy adhesion treatment methods include surface concavo-convex treatment methods such as sandblasting and solvent treatment methods, corona discharge treatment methods, chromic acid treatment methods, flame treatment methods, hot air treatment methods, ozone / ultraviolet irradiation treatment methods, etc. Examples thereof include an oxidation treatment method and a method of applying a primer containing a polyester resin or an acrylic resin to form a primer layer.

  Specifically, as the PET film subjected to the easy adhesion treatment, “EMBLET SG” manufactured by Unitika Co., Ltd., “Teijin Tetron Film G2” manufactured by Teijin Limited, “Lumirror S105” manufactured by Toray Industries, Inc., Examples thereof include “T100E” manufactured by Mitsubishi Chemical Polyester Film Co., Ltd.

  The resin film preferably has a thickness of 2 μm to 188 μm, more preferably 2 μm to 100 μm, still more preferably 2 μm to 50 μm, more preferably 2 μm. It is even more preferable to use a material having a thickness of ˜25 μm in order to further improve the adhesion to the foam material. Moreover, as the said resin film, when improving the workability | operativity at the time of manufacturing an adhesive tape, it is especially preferable to use what is 6 micrometers-25 micrometers.

[Adhesive layer (B)]
The pressure-sensitive adhesive layer (B) constituting the pressure-sensitive adhesive tape of the present invention is a layer formed using an aqueous pressure-sensitive adhesive composition. The said adhesive layer (B) is laminated | stacked on both surfaces of the said core base material (A).

  As the pressure-sensitive adhesive layer (B), it is preferable to use a layer having a 180-degree peeling adhesive strength to the foam material of 1.5 N / 20 mm or more from the standpoint of improving the pasting workability, and 1.8 N It is more preferable to use the one of / 20 mm to 6 N / 20 mm.

  When the adhesive strength of the pressure-sensitive adhesive layer (B) is peeled off 180 ° objectively, for example, one pressure-sensitive adhesive layer (B2) constituting the pressure-sensitive adhesive tape of the present invention is lined with a PET film having a thickness of 25 μm. Then, on the other adhesive layer (B1), a foam material having a thickness of 10 mm [manufactured by Inoac Corporation, trade name: ECS (gray), ether-based polyurethane foam] is used, and the thickness of the foam material is 5 mm. It is preferable that the adhesive strength when the adhesive tape is peeled in the direction of 180 degrees is 1.5 N / 20 mm or more, and 1.8 N / 20 mm to 6 N / 20 mm. It is more preferable that

  Further, the 180-degree peeling adhesive force tends to increase with time after being attached to the foam material. Therefore, the 180-degree peeling adhesive strength of the pressure-sensitive adhesive layer (B) constituting the pressure-sensitive adhesive tape of the present invention is 1.5 N / 20 mm or more when 30 minutes have elapsed after being applied to the foam material. Preferably, it is 1.6 N / 20 mm or more, more preferably 1.8 N / 20 mm or more.

  The pressure-sensitive adhesive layer (B) preferably has a thickness of 15 μm to 80 μm, more preferably 25 μm to 80 μm, and more preferably 45 μm to 80 μm. It is more preferable because it can further improve the adhesion to the surface and can impart excellent adhesion to the curved surface portion of the adherend.

  The pressure-sensitive adhesive layer (B) preferably has a gel fraction of 20% by mass to 45% by mass for measuring the insoluble content after the pressure-sensitive adhesive layer (B) is immersed in toluene for 24 hours. It is more preferable that the content is from 40% by mass to 40% by mass, and it is 30% by mass to 40% by mass that the adhesiveness to the foam material is further improved and the curved portion of the adherend is also excellent. Since adhesiveness can be provided, it is more preferable.

As said adhesive layer (B), what was formed by using an aqueous adhesive composition can be used.
As the aqueous pressure-sensitive adhesive composition, for example, various polymers, aqueous media, and those containing a tackifying resin and a crosslinking agent as required can be used.

  As the polymer, for example, an acrylic polymer, a rubber polymer, a silicone polymer, a urethane polymer, or the like can be used. Among these, it is preferable to use an acrylic polymer in order to develop excellent adhesiveness and the like.

  As said acrylic polymer, what is obtained by polymerizing vinyl monomers, such as a (meth) acryl monomer, can be used.

  As said acrylic polymer, what is obtained by superposing | polymerizing the monomer component containing various vinyl monomers can be used, for example.

  As the monomer component, a monomer component containing a (meth) acrylate having an alkyl group having 4 to 8 carbon atoms, a vinyl monomer having a carboxyl group, a vinyl monomer having a nitrogen atom, or the like. It is preferable to use what is obtained by polymerization.

  Examples of the alkyl (meth) acrylate having an alkyl group having 4 to 8 carbon atoms include 2-ethylhexyl acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, isooctyl ( (Meth) acrylates such as (meth) acrylate and n-octyl (meth) acrylate can be used. Among these, as the alkyl (meth) acrylate having an alkyl group having 4 to 8 carbon atoms, 2-ethylhexyl acrylate and n-butyl acrylate are preferably used, and 2-ethylhexyl acrylate is preferably used as a foam material. It is preferable to further improve the adhesion to the adhesive, and the combined use of 2-ethylhexyl acrylate and n-butyl acrylate further improves the adhesion to the foam material, and to the curved surface portion of the adherend Is more preferable because excellent adhesiveness can be imparted.

  The alkyl (meth) acrylate having an alkyl group having 4 to 8 carbon atoms is used in the range of 50% by mass to 99% by mass with respect to the total amount of monomer components used for producing the acrylic polymer. It is preferable to use in the range of 70% by mass to 98% by mass.

  The vinyl monomer having a carboxyl group is preferably used for imparting good water dispersion stability to the acrylic polymer. Moreover, since the vinyl monomer having a carboxyl group can be a cross-linking point with the cross-linking agent when a cross-linking agent described later is used, the adhesive layer (B) gives a higher cohesive force, It is preferably used for imparting excellent adhesiveness to the curved surface portion or the like of the adherend.

  Examples of the vinyl monomer having a carboxyl group include acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic anhydride, phthalic acid, phthalic anhydride, and crotonic acid. Among them, as the vinyl monomer having a carboxyl group, it is preferable to use acrylic acid and methacrylic acid, and the combined use of acrylic acid and methacrylic acid further improves the adhesiveness to the foam material. More preferred.

  The vinyl monomer having a carboxyl group is preferably used in the range of 0.5% by mass to 5.0% by mass with respect to the total amount of monomer components used for the production of the acrylic polymer. More preferably, it is used in the range of 1% by mass to 4.0% by mass, and the use in the range of 1.5% by mass to 3.0% by mass further improves the adhesion to the foam material. And more preferred.

  Examples of the vinyl monomer having a nitrogen atom include N-vinylpyrrolidone, N-vinylpiperidone, N-vinylmorpholinone, N-vinylcaprolactam, N-cyclohexylmaleimide, N-butylmaleimide, N-phenylmaleimide, N- ( (Meth) acryloylmorpholine, N- (meth) acryloylpyrrolidone, N- (meth) acryloylpiperidine, N- (meth) acryloylpyrrolidine, N- (meth) acryloyl-4-piperidone, acrylonitrile, (meth) acrylamide, N, N -Dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N-methylenebis ( 1) 1) acrylamide, N-isopropyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate Two or more species can be used, and N-vinylpyrrolidone and N-isopropyl (meth) acrylamide are preferably used.

  The use of the vinyl monomer having a nitrogen atom in combination with the vinyl monomer having a carboxyl group can impart a high cohesive force to the pressure-sensitive adhesive layer (B), and as a result, the curved surface of the adherend. It is more preferable because it can impart even better adhesiveness to the parts and the like and can maintain excellent adhesiveness for a long time even in a high temperature environment.

  The vinyl monomer having a nitrogen atom is preferably used in the range of 0.1% by mass to 5.0% by mass with respect to the total amount of monomer components used in the production of the acrylic polymer. More preferably, it is used in the range of 0.5% by mass to 4.0% by mass, and it is preferably used in the range of 0.5% by mass to 3.0% by mass with respect to the curved surface portion of the adherend. It is even more preferable because it can provide even more excellent adhesive properties and can maintain excellent adhesive properties for a long time even in a high temperature environment.

  As the polymer component used for the production of the acrylic polymer, other monomers can be used as necessary in addition to the above-described ones.

  As said other monomer, the (meth) acrylate which has a C1-C3 alkyl group can be used, for example.

  Examples of the alkyl (meth) acrylate having an alkyl group having 1 to 3 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and the like. can do. Especially, as said alkyl (meth) acrylate which has a C1-C3 alkyl group, it is preferable to use, for example, methyl (meth) acrylate and ethyl (meth) acrylate.

  When the alkyl (meth) acrylate having an alkyl group having 1 to 3 carbon atoms is used in combination with the alkyl (meth) acrylate having an alkyl group having 4 to 8 carbon atoms, the adhesiveness to the foam material is further improved. It is more preferable because it can be further improved and excellent adhesion can be imparted to the curved surface portion of the adherend.

  The alkyl (meth) acrylate having an alkyl group having 1 to 3 carbon atoms is used in the range of 1% by mass to 20% by mass with respect to the total amount of monomer components used for producing the acrylic polymer. It is preferable to use in the range of 1% by mass to 10% by mass.

  Examples of the other monomers include vinyl monomers having a hydroxyl group such as 4-hydroxybutyl (meth) acrylate, vinyl monomers having a keto group (or aldehyde group) such as diacetone acrylamide, 3- Silane vinyl monomers such as methacryloxypropylmethyldimethoxysilane, and vinyl monomers containing a phosphate group such as SIPOMER PAM-100 [manufactured by Rhodia Nikka Co., Ltd.] can be used.

  The acrylic polymer can be produced, for example, by polymerizing the monomer component by an emulsion polymerization method.

  When manufacturing the said acrylic polymer, an anionic emulsifier and a nonionic emulsifier can be used suitably as needed.

  As the emulsifier, in order to improve the water resistance and moisture resistance of the pressure-sensitive adhesive layer (B), it is possible to use an emulsifier having a polymerizable unsaturated group in the molecule called a known “reactive emulsifier”. preferable.

  Specific examples of the reactive emulsifier include Latemul PD-104 [manufactured by Kao Corporation], Aqualon KH-1025 [manufactured by Daiichi Kogyo Seiyaku Co., Ltd.], Adekaria Soap SE-10 [ADEKA Corporation]. It is particularly preferable that LATEMUL PD-104 and AQUALON KH-1025 are combined to improve the polymerization stability and the water resistance and moisture resistance.

  When the acrylic polymer is produced by an emulsion polymerization method, a polymerization initiator can be used.

  Examples of the polymerization initiator include azo-based initiators, persulfate-based initiators, peroxide-based initiators, carbonyl-based initiators, redox-based initiators such as a combination of persulfate and sodium bisulfite, and the like. Can be used.

  Among these, it is preferable to use a persulfate-based initiator or an azo-based initiator as the polymerization initiator.

  The pressure-sensitive adhesive layer (B) containing an acrylic polymer obtained by the above emulsion polymerization method using a persulfate-based initiator or an azo-based initiator can exhibit even better adhesion to a foam material. .

  Examples of the persulfate-based initiator include potassium persulfate and ammonium persulfate. As the azo initiator, 2,2 ′,-azobis (2-methylpropionamidine) dihydrochloride, 2,2′-azobis (2-methylpropionamidine) disulfate, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis [N- (2-arboxyethyl) -2-methylpropionamidine] hydrate, 2,2′-azobis (N, N′-di Methyleneisobutylamidine) dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, and the like can be used.

  In producing the acrylic polymer, a chain transfer agent can be used for the purpose of adjusting the molecular weight. As the chain transfer agent, for example, lauryl mercaptan, glycidyl mercaptan, mercaptoacetic acid, 2-mercaptoethanol, thioglycolic acid, 2-ethylhexyl thioglycolate, 2,3-dimethylcapto-1-propanol and the like can be used. .

  As the acrylic polymer obtained by the above method, those having a glass transition temperature of −70 ° C. to −50 ° C. are preferably used, and those having a temperature of −65 ° C. to −54 ° C. are more preferably used. It is further preferable to use a material having a temperature of -62 ° C to -57 ° C in order to impart even more excellent adhesiveness to the foam material. The glass transition temperature (Tg) is calculated from the FOX formula based on the glass transition temperature of the homopolymer of the monomer component used for the production of the acrylic polymer and the mass fraction of the monomer. Value. As the glass transition temperature of the homopolymer, values described in known materials can be employed, for example, -54 ° C for n-butyl acrylate, -70 ° C for 2-ethylhexyl acrylate, and 105 for methyl methacrylate. C., 80 DEG C. for N-vinylpyrrolidone, 106 DEG C. for acrylic acid, and 228 DEG C. for methacrylic acid.

  The acrylic polymer preferably has a weight average molecular weight of 300,000 to 1,200,000, more preferably 400,000 to 1,000,000, more preferably 450,000 to 800,000. It is further preferable to use a material in the range of the above in order to express even more excellent adhesiveness to the foam material.

  The said weight average molecular weight is standard polystyrene conversion by a gel permeation chromatography (GPC). As measurement conditions, TSKgel GMHXL [manufactured by Tosoh] is used as the column, the column temperature is 40 ° C., the eluent is tetrahydrofuran, the flow rate is 1.0 mL / min, and the standard polystyrene indicates a value using TSK standard polystyrene.

  The acrylic polymer obtained by the above method is preferably one that can be dispersed in an aqueous medium. The average particle diameter of the acrylic polymer particles is not particularly limited, but is preferably in the range of 100 nm to 500 nm. The average particle diameter means a 50% median diameter based on the volume of acrylic polymer particles, and the numerical value is based on a value obtained by measurement by a dynamic light scattering method.

  The aqueous medium in which the acrylic polymer can be dispersed or dissolved may be water alone or a mixed solvent of water and a water-soluble solvent.

  As the aqueous pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer (B), an aqueous dispersion of an acrylic polymer obtained by the emulsion polymerization method can be used. Moreover, it can manufacture by mixing the acrylic polymer and aqueous medium which were manufactured previously.

  The water-based pressure-sensitive adhesive composition forming the pressure-sensitive adhesive layer (B) is one containing the acrylic polymer in a range of 70 to 95% by mass with respect to the total amount of the water-based pressure-sensitive adhesive composition. Is preferred.

  The acrylic polymer preferably has an insoluble fraction with respect to toluene, a so-called gel fraction, of 0% by mass to 20% by mass, more preferably 0% by mass to 10% by mass. The content is more preferably 5% by mass to 5% by mass, and 0% by mass to 1% by mass is particularly preferable in order to further improve the adhesiveness to the foam material.

[Tackifying resin]
As said aqueous adhesive composition which forms the said adhesive layer (B), what contains tackifying resin can be used as needed.

  As the tackifying resin, an emulsion type tackifying resin is preferably used.

  Examples of the emulsion-type tackifying resins include rosin-based tackifying resins, polymerized rosin-based tackifying resins, polymerized rosin ester-based tackifying resins, rosin phenol-based tackifying resins, hydrogenated rosin ester-based tackifying resins, Examples include leveled rosin ester-based tackifier resins, terpene-based tackifier resins, terpene phenol-based tackifier resins, and aliphatic (petroleum resin) -based tackifier resins. Among them, as the tackifying resin, it is possible to use a polymerized rosin-based tackifier resin, a polymerized rosin ester-based tackifier resin, a rosinphenol-based tackifier resin, and a terpenephenol-based tackifier resin for excellent adhesion to a foam material. It is preferable for further improving the properties. In addition, by using a polymerized rosin ester tackifying resin and a rosin phenol tackifying resin in combination, the adhesion to the foam material is further improved and the adhesion to the curved surface of the adherend is also excellent. Is more preferable.

  Specific examples of the polymerized rosin ester-based tackifier resin include Superester E-625NT [Arakawa Chemical Industries, Ltd.], Superester E-650 [Arakawa Chemical Industries, Ltd.], Superester E-788. [Arakawa Chemical Industries, Ltd.], Super Ester E-786-60 [Arakawa Chemical Industries, Ltd.], Super Ester E-865 [Arakawa Chemical Industries, Ltd.], Super Ester E-865NT [Arakawa Chemical Co., Ltd.] Industrial Co., Ltd.], Harrie Star SK-508 [Harima Kasei Co., Ltd.], Harrier Star SK-508H [Harima Kasei Co., Ltd.], Harrier Star SK-816E [Harima Kasei Co., Ltd.], Harrier Star SK-822E [manufactured by Harima Kasei Co., Ltd.], Harrier Star SK-218NS [manufactured by Harima Kasei Co., Ltd.], Harrier Star SK-218MT [Harima Adult (Ltd.) HARIESTER SK-323NS [Harima Chemicals Co., Ltd.], and the like.

  Specific examples of the rosin phenol-based tackifier resin include Tamanoru E-100 [manufactured by Arakawa Chemical Industries, Ltd.], Tamanoru E-200 [manufactured by Arakawa Chemical Industries, Ltd.], Tamanoru E-200NT [Arakawa Chemical Industries, Ltd.] Etc.].

  Specific examples of tackifying resins that do not contain an aromatic organic solvent include Superester E-625NT, Superester E-865NT, Tamanol E-200NT, Harrier Star SK-218NS, Harrier Star SK-218MT, Harrier Star. SK-323NS etc. are mentioned.

  The softening point of the tackifying resin is preferably 120 ° C to 180 ° C, more preferably 140 ° C to 180 ° C. By containing a tackifying resin with a high softening point, it is possible to impart even better adhesion to the curved surface portion of the adherend, and to maintain excellent adhesion for a long time even in a high temperature environment. Therefore, it is more preferable.

  As content of tackifying resin, it is preferable that it is 5-40 mass parts with respect to 100 mass parts of said acrylic polymers, It is more preferable that it is 10-35 mass parts, 20 masses It is more preferable that the content is from 30 parts by mass to 30 parts by mass because it can provide more excellent adhesiveness to the foam material and more excellent adhesiveness to the curved surface portion of the adherend.

  As an aqueous pressure-sensitive adhesive composition that can be used for forming the pressure-sensitive adhesive layer (B), a composition containing a crosslinking agent can be used to further improve the cohesive strength of the pressure-sensitive adhesive layer (B). .

[Crosslinking agent]
As the crosslinking agent, known isocyanates, epoxy compounds, aziridine compounds, polyvalent metal salts, metal chelates, keto-hydrazide compounds, oxazoline compounds, silane compounds, glycidyl (alkoxy) epoxysilane compounds, and the like can be used.

  Among these, it is preferable to use an epoxy compound as the crosslinking agent in order to further improve the excellent adhesiveness to the foam material.

  Specific examples of the epoxy compound include: Denacol EX-832 [manufactured by Nagase Kasei Kogyo Co., Ltd.], Denacol EX-841 [manufactured by Nagase Kasei Kogyo Co., Ltd.], Tetrad C [Mitsubishi Gas Chemical ( Co., Ltd.], Tetrad X [Mitsubishi Gas Chemical Co., Ltd.] and the like, and Tetrad C is preferably used.

  The said crosslinking agent can be used in the range from which the gel fraction of an adhesive layer (B) becomes a desired range. For example, if an epoxy compound is used as the crosslinking agent, the epoxy compound is preferably used in the range of 0.01 to 0.1 parts by mass with respect to 100 parts by mass of the acrylic polymer. .

[Other additives]
The aqueous pressure-sensitive adhesive composition used for forming the pressure-sensitive adhesive layer (B) may contain other additives as long as the effects are not impaired.

  Other additives include plasticizers, softeners, antioxidants, fillers such as glass and plastic fibers, balloons, beads, and metal powders, colorants such as pigments and dyes, pH adjusters, and film formation aids. Agents, leveling agents, thickeners, water repellents, antifoaming agents and the like can be used.

[Release liner (C)]
The release liner (C) constituting the pressure-sensitive adhesive tape of the present invention has a tensile strength of 35 N / 5 mm or more when the release liner (C) is pulled at a speed of 20 m / min along the flow direction. There is also used one having a tensile strength of 35 N / 5 mm or more when the release liner (C) is pulled along the width direction at a speed of 20 m / min. By using the release liner (C) having such tensile strength, it is possible to prevent the release liner from being broken when the release liner is peeled off. As a result, the adhesive tape is applied to an adherend such as a foam material. It is possible to prevent a decrease in work efficiency.

  The release liner (C) preferably has a tensile strength in the flow direction of 45 N / 5 mm or more, a tensile strength in the width direction of 35 N / 5 mm or more, and a tensile strength in the flow direction of 45 N / 5 mm or more. More preferably, the tensile strength in the width direction is 40 N / 5 mm or more, the tensile strength in the flow direction is 55 N / 5 mm or more, and the tensile strength in the width direction is 45 N / 5 mm or more. Further preferred. Moreover, it is preferable that the upper limits of the tensile strength in the flow direction and the width direction of the release liner (C) are both 125 N / 5 mm.

  Further, as the release liner (C) used in the present invention, the softness of the release liner (C) measured in accordance with the JIS L 1085 standard and using a Gurley tester along the flow direction. Is 1,000 mg or more, and the release liner (C) has a bending resistance measured along the width direction of 1,000 mg or more. By using such a release liner (C), it is possible to prevent the release liner from being broken when the release liner is peeled off, and as a result, work efficiency when sticking the adhesive tape to an adherend such as foam material. Can be prevented.

  The release liner (C) has a stiffness in the flow direction of 2,000 mg or more, and preferably has a stiffness in the width direction of preferably 1,000 mg or more. More preferably, the stiffness in the width direction is 1,200 mg or more, the stiffness in the flow direction is 2,000 mg or more, and the stiffness in the width direction is 1,300 mg. It is even more preferable that the bending resistance in the flow direction is 2,000 mg or more, and it is particularly preferable that the bending resistance in the width direction is 2,000 mg or more.

  The tensile strength and bending resistance of the release liner (C) can be adjusted within the predetermined range by appropriately setting the material constituting the release liner (C), the laminated structure, and the like. Specifically, the tensile strength and bending resistance of the release liner (C) include the type and basis weight of the base paper constituting it, the presence or absence of a resin layer such as a polyolefin layer, the thickness of the resin layer, the release liner It can adjust suitably by adjusting the total thickness, total basis weight, etc. of (C). Moreover, when adjusting the peeling load of the said release liner (C) in a desired range, it is suitable to adjust the kind and application quantity of the silicone layer which comprise a release liner (C).

  The release liner (C) has a resin layer such as a polyolefin layer on one side or both sides of the base paper for providing the predetermined tensile strength and bending resistance, and a silicone layer on the outer side of the resin layer. It is preferable to use one having

  Examples of the base paper constituting the release liner (C) include high-quality paper, medium-quality paper, thin paper, glassine paper, and coated paper. In particular, it is preferable to use high-quality paper as the base paper in order to obtain a release liner that satisfies both the predetermined range of tensile strength and bending resistance.

  As the fine paper, it is preferable to use softwood bleached sulfate pulp (N material) alone or one containing softwood bleached sulfate pulp (N material), and softwood bleached sulfate pulp (N material) and hardwood bleached sulfuric acid. It is more preferable to use a mixture of salt pulp (L material), and among the mixture of softwood bleached sulfate pulp (N material) and hardwood bleached sulfate pulp (L material), softwood bleached sulfate pulp It is more preferable to use a material having a high ratio of (N material) in order to adjust the bending resistance of the release liner (C) to the predetermined range.

As the base paper, it is preferred to use a range of basis weight ^{20g / m 2 ~150g / m 2} , more preferably to use a range of ^{60g / m 2 ~130g / m 2} , 70g / it is more preferred to use a range of ^{m 2} ~120g / m ^2, still more preferred to use a range of ^{75g / m 2 ~110g / m 2} , 75g / m 2 ~85g / m 2 Using a material in the above range provides a release liner (C) that achieves both the tensile strength and the bending resistance within the predetermined range without impairing workability during the production of the release liner (C). Particularly preferred.

  The base paper constituting the release liner (C) may contain an internal addition type wet paper strength enhancer, a dry paper strength enhancer, and a surface type paper strength enhancer. An internal addition type dry paper strength enhancer and a surface type paper strength enhancer are more preferable, and it is more preferable to use both paper strength enhancers in combination. Examples of the internally added dry paper strength enhancer include cationized starch and polyacrylamide polymers. Examples of the surface type paper strength enhancer include modified starch and polyvinyl alcohol.

  In preparing the base paper, other additives such as a sizing agent, a yield improver, a drainage improver, an antifoaming agent, a dispersant, a bleaching agent and a dye may be added.

  The method for making the base paper is not particularly limited, and may be prepared by, for example, a circular net paper machine, a short net paper machine, a long net paper machine, or the like.

  As the release liner (C), it is preferable to use one having a polyolefin layer provided on both sides or one side of the base paper in order to adjust its tensile strength and bending resistance within the above ranges.

  Examples of the polyolefin layer include a layer formed using polyethylene, polypropylene, or the like, and a resin layer formed using polyethylene or the like is preferable.

  The release liner (C) preferably has a resin layer with a thickness in the range of 10 μm to 40 μm in order to adjust the tensile strength and the bending resistance within the above ranges. It is more preferable to use those having a resin layer in the range of ˜30 μm, and it is more preferable to use those having a resin layer in the range of 23 μm to 27 μm.

  The polyolefin layer can be formed, for example, by applying polyethylene to one or both sides of the base paper with a T-die extruder and laminating.

  The tear strength of the release liner (C) is not particularly limited, but is preferably 0.5N to 2N. The tear strength here is based on the strength when tearing at a rate of 0.2 m / min after scissors are cut at the center of the end of the release liner.

  The release liner (C) has a peeling load of 1 N / 20 mm or less when the release liner (C) is peeled from the pressure-sensitive adhesive layer (B) in the 180 degree direction at 5 m / min. The use of a material can prevent the release liner from tearing when the release liner is peeled off, and as a result, prevents a reduction in work efficiency when the double-sided adhesive tape is applied to an adherend such as a foam material. Therefore, it is preferably 0.01 N / 20 mm to 0.5 N / 20 mm, more preferably 0.01 N / 20 mm to 0.4 N / 20 mm, and further preferably 0.1 N / 20 mm to 0. 3N / 20 mm is particularly preferable, and 0.12 N / 20 mm to 0.22 N / 20 mm is particularly preferable.

  The release liner (C) has a peeling load of 1 N / 20 mm or less when the release liner (C) is peeled from the pressure-sensitive adhesive layer (B) in the 180 ° direction at 20 m / min. When the release liner is peeled off, the release liner can be prevented from being torn, and as a result, the work efficiency when the double-sided adhesive tape is applied to an adherend such as a foam material is reduced. Since it can prevent, it is preferable, it is more preferable that it is 0.01N / 20mm-0.7N / 20mm, it is further more preferable that it is 0.01N / 20mm-0.5N / 20mm, 0.1N / 20mm- It is particularly preferably 0.4 N / 20 mm, and particularly preferably 0.1 N / 20 mm to 0.2 N / 20 mm.

In addition, as the release liner (C), even if the peeling speed is increased, a release load that does not become heavy, that is, a material having a small speed dependency is used. The mold liner can be prevented from being broken, and as a result, it is possible to prevent a reduction in work efficiency when the double-sided pressure-sensitive adhesive tape is applied to an adherend such as a foam material. The release liner (C) from the pressure-sensitive adhesive layer (B) to the release liner (C) is 20 m / min in the 180 ° direction with respect to the peeling load [R _5m ] when the mold liner (C) is peeled off in the 180 ° direction at 5 m / min. The peel load [R _20m ] ratio [R _20m / R _5m ] is preferably 1 to 3, more preferably 1 to 2.5, and more preferably 1 to 2. Is more preferred, 1 And particularly preferably 1 to 1.5.

  The release liner (C) should have a silicone layer on the surface of the polyolefin layer in order to adjust the peel load when the release liner (C) is peeled from the pressure-sensitive adhesive layer (B) to the above range. Is preferred.

  The silicone layer is preferably a layer containing an addition reaction type, a condensation reaction type, or a UV curing reaction type silicone release agent in order to give the predetermined release load, and an addition reaction type silicone release. A layer containing an agent is more preferable in adjusting the peeling load when peeling at a high speed to the above range. The silicone layer may contain a heavy release additive, a catalyst, and the like as necessary in appropriately adjusting the peeling load.

  Examples of the addition reaction type silicone release agent include KS-847T (manufactured by Shin-Etsu Chemical Co., Ltd.), KS-774 (manufactured by Shin-Etsu Chemical Co., Ltd.), and KS-776A (manufactured by Shin-Etsu Chemical Co., Ltd.). KS-778 [manufactured by Shin-Etsu Chemical Co., Ltd.], KS-779H [manufactured by Shin-Etsu Chemical Co., Ltd.], KS-830 [manufactured by Shin-Etsu Chemical Co., Ltd.], KS-837 [Shin-Etsu Chemical Co., Ltd.] KS-839L [Shin-Etsu Chemical Co., Ltd.], KS-3502 [Shin-Etsu Chemical Co., Ltd.], KS-3703 [Shin-Etsu Chemical Co., Ltd.], SRX357 [Toray Dow Corning Co., Ltd.] )], BY23-749 [Toray Dow Corning Co., Ltd.], SD7333 [Toray Dow Corning Co., Ltd.], BY24-179 [Toray Dow Corning Co., Ltd.], SRX211 [Toray Dow Corning] Co., Ltd.], BY23-746 [Toray Dow Corning Co., Ltd.], SRX345 [Toray Dow Corning Co., Ltd.], BY24-4103 [Toray Dow Corning Co., Ltd.], SD7320 [Toray Dow Corning] Corning Co., Ltd.], SD7236 [Toray Dow Corning Co., Ltd.] and the like.

  Examples of the heavy release additive include KS-3800 [manufactured by Shin-Etsu Chemical Co., Ltd.], SD7292 [manufactured by Toray Dow Corning Co., Ltd.], BY24-843 [manufactured by Toray Dow Corning Co., Ltd.], BY24-4980. [Toray Dow Corning Co., Ltd.] and the like.

  As the catalyst, a platinum-based catalyst can be suitably used. SRX212 [manufactured by Toray Dow Corning Co., Ltd.], NC-25 [manufactured by Toray Dow Corning Co., Ltd.], CAT-PL-50T [Shin-Etsu Chemical Co., Ltd. ( Etc.].

The coating amount of the silicone layer, in order to adjust the peeling load in a predetermined ^range, preferably in the range of ^{0.5g / m 2 ~1.0g / m 2} . In adjusting the coating amount as appropriate, the silicone release agent may be diluted with an organic solvent such as toluene. When preparing a diluted solution, it is preferable that it is in the range of 1% by mass to 10% by mass in order to adjust the coating amount to a predetermined range.

  As a method of forming the silicone layer, a silicone resin diluted with an organic solvent such as toluene is applied to the surface of the resin layer using a direct gravure coater, an offset gravure coater, a Mayer bar coater, a 5-roll coater, or the like. The method of applying and drying is mentioned. The silicone layer is preferably dried at 90 ° C. to 110 ° C. for 3 seconds to 40 seconds and cured. Moreover, it is preferable that the said silicone layer is hardened | cured and formed over 48 hours or more at 30 to 60 degreeC after the said cure.

  The release liner (C) is 0.5 N / 20 mm or less with respect to a 90 μm thick adhesive layer formed using “SK Dyne 801B” (Soken Chemical Co., Ltd., solvent-based adhesive). It is preferable to have a peeling load of 0.3 N / 20 mm or less, more preferably 0.25 N / 20 mm or less, and 0.16 N / 20 mm or less. The mold liner (C) is particularly preferable because it is easy to peel off and the work efficiency is improved. The release load was applied on the release liner (C) by applying “SK Dyne 801B” (manufactured by Soken Chemical Co., Ltd., solvent-based adhesive) to a thickness of 90 μm after drying. After that, a 75 μm thick PET film was affixed to the surface, cured for 20 hours in an environment of 40 ° C., the release liner side of the test piece cut to a width of 20 mm was grasped, and the strength when peeled off in the 180 ° direction was obtained. Is based.

  As the release liner (C), it is preferable to use one having a total thickness in the range of 100 μm to 200 μm, in order to adjust its tensile strength and bending resistance within the above ranges, and in the range of 120 μm to 150 μm. It is more preferable to use a thing, and it is especially preferable to use the thing of the range of 130 micrometers-140 micrometers.

  The pressure-sensitive adhesive tape of the present invention is a method of directly applying the aqueous pressure-sensitive adhesive composition to one or both sides of the core base material (A) using a roll coater or a die coater, and the release liner (C). After applying the aqueous pressure-sensitive adhesive composition on the surface using a roll coater, a die coater or the like to form a pressure-sensitive adhesive layer (B), the pressure-sensitive adhesive layer (B) is attached to one side of the core substrate (A) or It can be manufactured by a method of transferring to both sides.

  After the pressure-sensitive adhesive tape of the present invention is manufactured by the above-described manufacturing method, curing in the range of 20 ° C. to 50 ° C. for 48 hours or more causes the crosslinking reaction of the pressure-sensitive adhesive layer (B) to proceed, It is preferable for improving heat resistance and adhesiveness.

The adhesive tape after curing was soaked in toluene for 24 hours in a mass (G ₀ ) of the core substrate (A), a mass of the double-sided adhesive tape (G ₁ ), and a 25 ° C. environment. Then, it is preferable that the gel fraction (following formula) calculated based on the mass (G ₂ ) of what was then dried under an environment of 105 ° C. is in the range of 20% by mass to 45% by mass, and 25% by mass to 40%. More preferably, it is in the range of 30% by mass, and 30% by mass to 40% by mass is particularly preferable because it is excellent in adhesiveness to the foam material and the release liner is hardly broken.
Gel fraction (% by mass) = [(G ₂ −G ₀ ) / (G ₁ −G ₀ )] × 100

  As the pressure-sensitive adhesive tape of the present invention, it is preferable to use a tape having a total thickness of the core base material (A) and the pressure-sensitive adhesive layer (B) in the range of 80 μm to 200 μm, preferably 100 μm to 160 μm. It is particularly preferable to use a resin having a thickness within the range because the adhesiveness to the foam material is excellent and the release liner is hardly broken.

  The pressure-sensitive adhesive tape of the present invention is excellent in adhesiveness to the material even though the surface shape such as foam material has large irregularities. In addition to this, the release liner is broken when the release liner is peeled off in the process of stamping into a desired shape with the double-sided adhesive tape and foam material pasted together, and then sticking to automobile parts, etc. Since it can be easily peeled off, it is excellent in workability for joining to a vehicle body or a TV case. Unlike conventional adhesives based on solution-polymerized acrylic resins, the use of water-dispersed acrylic adhesives can be expected to reduce volatile organic compounds. It can be suitably used as a double-sided pressure-sensitive adhesive tape for fixing a foam material or the like to parts inside various products in industrial applications such as OA and home appliance industries.

  Next, the present invention will be described in detail with reference to examples and comparative examples. The evaluation method of each characteristic of the double-sided adhesive tape obtained by the Example and the comparative example is as follows.

[Tensile strength of release liner]
Five test pieces 1 were prepared by cutting the release liner into a dimension of 5 mm in the flow direction and 180 mm in the width direction.

  The tensile strength in the width direction of the test piece 1 was measured and averaged using a high-speed tensile tester [manufactured by Tester Sangyo Co., Ltd.] under conditions of a marked line interval of 150 mm and a tensile speed of 20 m / min.

  Five test pieces 2 were prepared by cutting the release liner into a dimension of 180 mm in the flow direction and 5 mm in the width direction.

  The tensile strength in the width direction of the test piece 2 was measured and averaged using a high-speed tensile tester [manufactured by Tester Sangyo Co., Ltd.] under conditions of a marked line interval of 150 mm and a tensile speed of 20 m / min.

[Bending softness of release liner]
The bending resistance of the release liner was measured according to JIS L 1085 standard.

  Five test pieces 3 were prepared by cutting the release liner into a dimension of 20 mm in the flow direction and 340 mm in the width direction.

  Next, using a Gurley-type bending resistance tester [manufactured by Tester Sangyo Co., Ltd., model: ST-401], five test pieces 3 were fixed with a stacked chuck.

  Next, a load of 25 g was applied at a distance of 10 cm from the fulcrum to rotate the arm at a constant speed, and the scale (RG) when the test piece 3 was separated from the pendulum was read. The measurement was performed 5 times for each of the front and back sides, and the average value was calculated. Based on the measured value, the bending resistance was calculated from the following equation.

Formula: Bending softness (mg) = (RG) × 10 × 25 × (3.4 × 3.4 ÷ 2) × 0.306
Five test pieces 4 were prepared by cutting the release liner into a dimension of 340 mm in the flow direction and 20 mm in the width direction.

  Next, using a Gurley-type bending resistance tester [manufactured by Tester Sangyo Co., Ltd., model: ST-401], five test pieces 4 were fixed with a stacked chuck.

Next, a load of 25 g was applied 10 cm away from the fulcrum to rotate the arm at a constant speed, and the scale (RG) when the test piece 4 was separated from the pendulum was read. The measurement was performed 5 times for each of the front and back sides, and the average value was calculated. Based on the measured value, the bending resistance was calculated from the following equation.
Formula: Bending softness (mg) = (RG) × 10 × 25 × (3.4 × 3.4 ÷ 2) × 0.306

[Release load of release liner 1 (801B method)]
“SK Dyne 801B” (manufactured by Soken Chemical Co., Ltd., solvent-based adhesive) is applied to the release liner so that the thickness after drying is 90 μm, and after drying, it is attached to a 75 μm thick PET film. The test piece 5 was obtained by curing for 20 hours in a 40 ° C. environment and cutting to a width of 20 mm. The release liner of the test piece 5 was grasped, and using a high-speed peel tester [manufactured by Tester Sangyo Co., Ltd.], the peel load when peeled at a speed of 5 m / min in the 180 degree direction was measured.

[Release load 2 of release liner]
A test piece 6 was obtained by cutting a double-sided adhesive tape into a width of 20 mm. Under the environment of 23 ° C. and 50% RH, the release liner of the test piece 6 was grasped, and using a high speed peel tester [manufactured by Tester Sangyo Co., Ltd.], 5 m / min and 20 m in the direction of 180 degrees from the adhesive layer. The peeling load at the time of peeling at a speed of / min was measured.

[Release load of release liner 3 (Applicability of manual release of release liner 1)]
The release liner on one side of the double-sided pressure-sensitive adhesive tape is peeled off, and bonded to an ether-based urethane foam having a thickness of 10 mm (see FIG. 1), and punched into a 60 mm long and 60 mm wide square to obtain a test piece 7 (see FIG. 2). It was.

From one corner (point A in FIG. 2) of the test piece 7 to the diagonal direction (point B direction in FIG. 2), the other release liner constituting the test piece 7 is moved at a speed of 20 m / min. The ease of peeling at the time of peeling was evaluated. Five testers carried out three times for each test piece, and the most frequent evaluation was adopted.
A: The release liner did not break and could be peeled off with a light force.
○: The release liner was not torn and it was able to be peeled off although it was somewhat heavy.
Δ: The release liner was torn once or twice.
X: The release liner was broken 3 times.

[Release load 4 of release liner (Applicability 2 for release of release liner)]
The test piece 7 (see FIGS. 1 and 2) obtained by peeling off the release liner on one side of the double-sided pressure-sensitive adhesive tape and pasting it with an ether-based urethane foam having a thickness of 10 mm was tested by punching into the shape shown in FIG. Piece 8 was obtained.

From one corner (point A in FIG. 3) of the test piece 8 to the diagonal direction (point B direction in FIG. 3), the other release liner constituting the test piece 8 is moved at a speed of 20 m / min. The ease of peeling at the time of peeling was evaluated. Five testers carried out three times for each test piece, and the most frequent evaluation was adopted.
A: The release liner did not break and could be peeled off with a light force.
○: The release liner was not torn and it was able to be peeled off although it was somewhat heavy.
Δ: The release liner was torn once or twice.
X: The release liner was broken 3 times.

[180 degree peeling adhesion to foam material]
180 degree peeling adhesion was measured according to JIS Z 0237.

  After peeling off the release liner on one side of the double-sided adhesive tape and backing with a 25 μm thick PET film, the release liner on the other side was peeled off, and a 10 mm thick ether-based urethane foam [manufactured by Inoac Corporation, The product was bonded to a product name; ECS] with a compressive load such that the thickness of the urethane foam was 5 mm. A laminate of an ether-based urethane foam and a double-sided adhesive tape was cut into a size of 20 mm in width and 100 mm in length to obtain a test piece 9.

  The test piece 9 was allowed to stand for 30 minutes in an environment of 23 ° C. and 50% RH, and then tested using a Tensilon tensile tester [manufactured by A & D Corporation, model: RTM-100] in an environment of 23 ° C. and 50% RH. The adhesive force when the double-sided pressure-sensitive adhesive tape constituting the piece 9 was peeled from the urethane foam at a speed of 300 mm / min in the direction of 180 degrees was measured. In addition, the measurement was performed 3 times and the average value was calculated.

  Further, the adhesive strength after leaving the test piece 9 in a 23 ° C., 50% RH environment for 24 hours, and the adhesion strength after leaving the test piece 9 in a 23 ° C., 50% RH environment for 72 hours. The force was measured in the same manner as above.

[Tear strength]
A 25 mm long cut is made in the center of the widthwise end of the release liner cut to a width of 50 mm and a length of 100 mm, and then a Tensilon tensile tester [manufactured by A & D Co., Ltd., model: RTM-100] is used. The strength at the time of tearing at a speed of 0.2 m / min was measured.

(Preparation Example 1)
<Preparation of emulsion>
In a container, 75 g of ion-exchanged water and Aqualon KH-1025 [Daiichi Kogyo Seiyaku Co., Ltd .; active ingredient 25% by mass] as a surfactant and Latem PD-104 [Kao Co., Ltd .; active ingredient 20% by mass] 37.5 g was added and dissolved uniformly. Thereto, 47.5 g of n-butyl acrylate, 410 g of 2-ethylhexyl acrylate, 25 g of methyl methacrylate, 12.5 g of acrylic acid, 5 g of N-vinyl-2-pyrrolidone and 0.3 g of lauryl mercaptan were added to emulsify, and emulsion 632 .8 g was obtained.

<Preparation of Acrylic Polymer Aqueous Dispersion (1)>
In a reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, a thermometer, and a dropping funnel, 287.5 g of deionized water was placed, and the temperature was raised to 55 ° C. while blowing nitrogen. While stirring, a part of the emulsion [6.33 g], 0.5 g of ammonium persulfate aqueous solution [6% by mass of active ingredient], and 0.5 g of sodium hydrogen sulfite aqueous solution [2% by mass of active ingredient] were added and maintained at 55 ° C. The polymerization was performed in 1 hour. Subsequently, the remaining emulsion 626.47 g and the azo initiator V-501 [manufactured by Wako Pure Chemical Industries, Ltd.] 20 g of aqueous solution [active ingredient 5% by mass] were used in a separate funnel. While maintaining at 55 ° C., dropwise polymerization was performed over 6 hours. After completion of dropping, the reaction vessel was stirred for 2 hours while maintaining the temperature at 60 ° C., and then the contents were cooled and adjusted with ammonia water [10% by mass of active ingredient] so that the pH was 8.0. This was filtered through a 200 mesh wire net to obtain an aqueous dispersion (1) of an acrylic polymer. The solid content concentration of the acrylic polymer aqueous dispersion (1) was 50% by mass, the average particle size of the acrylic polymer contained therein was 300 nm, and the weight average molecular weight was 520,000.

<Preparation of acrylic pressure-sensitive adhesive composition>
Acrylic polymer aqueous dispersion (1) 1000 g, Surfinol PSA-336 [Air Products Japan Co., Ltd.] 2.5 g as leveling agent, Surfynol DF-110D [Air Products] as antifoaming agent -Japan Co., Ltd.] 2.5g, Super Ester E-865NT which is an emulsion type polymerized rosin ester type tackifying resin as a tackifying resin [Arakawa Chemical Industries, Ltd., softening point 160 ° C, solid content concentration 50 mass %] 100 g, Tamanol E-200NT (made by Arakawa Chemical Industry Co., Ltd., softening point 150 ° C., solid content concentration 53 mass%) 94.34 g which is an emulsion type rosin phenol-based tackifying resin was added, and 100 mesh wire mesh was used. The acrylic pressure-sensitive adhesive composition (1) was obtained by filtration. The gel fraction of the acrylic pressure-sensitive adhesive composition (1) was 0.1% by mass.

<Preparation of acrylic adhesive>
To the total amount of the acrylic pressure-sensitive adhesive composition (1) obtained above, 1.5 g of a 10 mass% ethanol solution of Tetrad C [manufactured by Mitsubishi Gas Chemical Co., Ltd., epoxy compound] as a crosslinking agent was added with stirring. And cured for one week in a 23 ° C. environment to obtain an acrylic pressure-sensitive adhesive (1).

(Preparation Example 2)
Preparation Example 1 except that n-butyl acrylate was changed from 47.5 g to 50 g, 2-ethylhexyl acrylate was changed from 410 g to 412.5 g, and N-vinyl-2-pyrrolidone was changed from 5 g to 0 g. In the same manner, an aqueous dispersion (2) of an acrylic polymer was prepared. The solid content concentration of the aqueous dispersion (2) of the acrylic polymer was 50% by mass, the average particle size of the acrylic polymer contained therein was 310 nm, and the weight average molecular weight was 550,000.

  An acrylic pressure-sensitive adhesive composition (in the same manner as in Preparation Example 1 except that the acrylic polymer aqueous dispersion (2) was used instead of the acrylic polymer aqueous dispersion (1). 2) was prepared. The gel fraction of the said acrylic adhesive composition (2) was 0.2 mass%.

  An acrylic pressure-sensitive adhesive (2) was prepared in the same manner as in Preparation Example 1, except that the acrylic pressure-sensitive adhesive composition (2) was used instead of the acrylic pressure-sensitive adhesive composition (1).

(Preparation Example 3)
An acrylic polymer aqueous dispersion (3) was prepared in the same manner as in Preparation Example 2, except that the amount of acrylic acid used was changed from 12.5 g to 7.5 g and methacrylic acid was used in an amount of 5 g. . The solid concentration of the acrylic polymer aqueous dispersion (3) was 50% by mass, the average particle size of the acrylic polymer contained therein was 308 nm, and the weight average molecular weight was 540,000.

  An acrylic pressure-sensitive adhesive composition (in the same manner as in Preparation Example 1 except that the acrylic polymer aqueous dispersion (3) was used instead of the acrylic polymer aqueous dispersion (1). 3) was prepared. The gel fraction of the acrylic pressure-sensitive adhesive composition (3) was 0.1% by mass.

  An acrylic pressure-sensitive adhesive (3) was prepared in the same manner as in Preparation Example 1, except that the acrylic pressure-sensitive adhesive composition (3) was used instead of the acrylic pressure-sensitive adhesive composition (1).

(Preparation Example 4)
In the same manner as in Preparation Example 1, except that the amount of Superester E-865NT [Arakawa Chemical Industries, Ltd., softening point 160 ° C., solid content concentration 50 mass%] was changed from 100 g to 200 g, acrylic was used. A pressure-sensitive adhesive composition (4) was prepared. The gel fraction of the said acrylic adhesive composition (4) was 0.1 mass%.

  An acrylic pressure-sensitive adhesive (4) was prepared in the same manner as in Preparation Example 1, except that the acrylic pressure-sensitive adhesive composition (4) was used instead of the acrylic pressure-sensitive adhesive composition (1).

(Preparation Example 5)
The same method as in Preparation Example 1 except that the amount of Tamanol E-200NT [Arakawa Chemical Industries, Ltd., softening point 150 ° C., solid content concentration 53 mass%] was changed from 94.34 g to 188.68 g. Acrylic pressure-sensitive adhesive composition (5) was prepared. The gel fraction of the acrylic pressure-sensitive adhesive composition (5) was 0.1% by mass.

  A water-dispersed acrylic pressure-sensitive adhesive (5) was prepared in the same manner as in Preparation Example 1, except that the acrylic pressure-sensitive adhesive composition (5) was used instead of the acrylic pressure-sensitive adhesive composition (1). Prepared.

<Manufacture of double-sided adhesive tape>
Example 1
Thickness is obtained by extruding polyethylene at 310 ° C. with a T-die extruder on both sides of high-quality paper [Nippon Paper Co., Ltd., N / L mixed, basis weight 78 g / m ² ], and then cooling and laminating. A 20 μm polyolefin layer was formed. Addition-type silicone release agent [Toray Dow Corning Co., Ltd., trade name: SD7333] 100 parts by mass of platinum catalyst [Toray Dow Corning Co., Ltd., trade name: SRX212] 1 part by mass is added to toluene. And a coating solution having a solid content concentration of 5% by mass was prepared. This coating solution is applied to the upper surface of the polyethylene layer so that the coating amount is 0.6 g / m 2 (solid content), dried at 100 ° C. for 10 seconds and cured to form a silicone layer. Cured for 72 hours in a 40 ° C. environment to obtain a release liner (1). The obtained release liner (1) has a total basis weight of 118 g / m ² , a total thickness of 125 μm, a tensile strength in the flow direction of 52 N / 5 mm, and a tensile strength in the width direction of 40 N / 5 mm. The bending resistance in the direction was 2100 mg, the bending resistance in the width direction was 1390 mg, the tear strength in the flow direction was 0.6 N, and the peel load 1 (801B method) was 0.12 N / 20 mm.

  The release liner (1) is coated with the acrylic pressure-sensitive adhesive (1) prepared in Preparation Example 1 so that the thickness after drying is 65 μm, and dried. Two sheets having an adhesive layer thereon were prepared.

Next, both sides of a nonwoven fabric [made by Isagawa Paper Co., Ltd., trade name: DI-Tex LCN, pulp / rayon (mass ratio) = 5/5, basis weight 14 g / m ² , thickness 38 μm] which is a core base material Then, the pressure-sensitive adhesive layer of the sheet was transferred and cured at 40 ° C. for 48 hours to obtain a double-sided pressure-sensitive adhesive tape (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (1) was 36.8% by mass.

(Example 2)
A release liner (2) was prepared in the same manner as in Example 1 except that the thickness of the polyolefin layer was changed from 20 μm to 25 μm. The obtained release liner (2) has a total basis weight of 127 g / m 2, a total thickness of 135 μm, a tensile strength in the flow direction of 60 N / 5 mm, a tensile strength in the width direction of 50 N / 5 mm, and a flow direction. Was 2130 mg, the width direction bending resistance was 1410 mg, the tearing strength in the flow direction was 0.6 N, and the peel load 1 (801B method) was 0.12 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (2) was prepared in the same manner as in Example 1 except that the release liner (2) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (2) was 36.8% by mass.

(Example 3)
Instead of a coating liquid in which an addition type silicone release agent (SD7333) and a platinum type catalyst (SRX212) are mixed, an addition type silicone release agent [manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KS-847T] 100 1 part by weight of platinum catalyst [Shin-Etsu Chemical Co., Ltd., trade name: CAT-PL-50T] was added to parts by weight, and a coating solution prepared by dissolving in toluene to a solid content concentration of 5% by weight was used. Except for the above, a release liner (3) was prepared in the same manner as in Example 2. The obtained release liner (3) has a total basis weight of 127 g / m 2, a total thickness of 135 μm, a tensile strength in the flow direction of 59 N / 5 mm, a tensile strength in the width direction of 49 N / 5 mm, and a flow direction. Was 2120 mg, the bending resistance in the width direction was 1400 mg, the tear strength in the flow direction was 0.6 N, and the peel load 1 (801B method) was 0.16 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (3) was prepared in the same manner as in Example 1 except that the release liner (3) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (3) was 36.8% by mass.

Example 4
Instead of a coating liquid in which an addition type silicone release agent (SD7333) and a platinum type catalyst (SRX212) are mixed, an addition type silicone release agent [manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KS-847T] 100 5 parts by mass of heavy release additive [manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KS-3800], platinum catalyst [manufactured by Shin-Etsu Chemical Co., Ltd., trade name: CAT-PL-50T] in 1 part by mass A release liner (4) was prepared in the same manner as in Example 2, except that a coating solution prepared by adding a part and dissolving in toluene to a solid content concentration of 5% by mass was used. The obtained release liner (4) has a total basis weight of 127 g / m 2, a total thickness of 135 μm, a tensile strength in the flow direction of 60 N / 5 mm, a tensile strength in the width direction of 48 N / 5 mm, and a flow direction. The bending resistance was 2070 mg, the bending resistance in the width direction was 1390 mg, the tear strength in the flow direction was 0.6 N, and the peel load 1 (the 801B method) was 0.20 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (4) was prepared in the same manner as in Example 1 except that the release liner (4) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (4) was 36.8% by mass.

(Example 5)
100 mass of addition type silicone release agent [manufactured by Toray Dow Corning Co., Ltd., trade name: SRX345] instead of a coating liquid in which addition type silicone release agent (SD7333) and platinum catalyst (SRX212) are mixed. Except for using a coating solution prepared by adding 1 part by mass of a platinum catalyst [trade name: SRX212] manufactured by Toray Dow Corning Co., Ltd. In the same manner as in Example 2, a release liner (5) was prepared. The obtained release liner (5) has a total basis weight of 127 g / m 2, a total thickness of 135 μm, a tensile strength in the flow direction of 60 N / 5 mm, a tensile strength in the width direction of 48 N / 5 mm, and a flow direction. The bending strength of the film was 2110 mg, the bending resistance in the width direction was 1400 mg, the tear strength in the flow direction was 0.6 N, and the peel load 1 (the 801B method) was 0.28 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (5) was prepared in the same manner as in Example 1 except that the release liner (5) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (5) was 36.8% by mass.

(Example 6)
The same as in Example 4 except that high-quality paper [manufactured by Nippon Paper Industries Co., Ltd., N material / L material mixed, basis weight 81 g / m ² ] was used instead of high-quality paper (basis weight 78 g / m ² ). The release liner (6) was prepared by the method. The obtained release liner (6) has a total basis weight of 130 g / m 2, a total thickness of 135 μm, a tensile strength in the flow direction of 62 N / 5 mm, a tensile strength in the width direction of 53 N / 5 mm, and a flow direction. The bending strength was 2220 mg, the bending strength in the width direction was 1510 mg, the tear strength in the flow direction was 0.7 N, and the peel load 1 (801B method) was 0.20 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (6) was prepared in the same manner as in Example 1 except that the release liner (6) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (6) was 36.8% by mass.

(Example 7)
The same as in Example 4 except that high-quality paper [Nippon Paper Industries Co., Ltd., N / L mixed material, basis weight 110 g / m ² ] was used instead of high-quality paper (basis weight 78 g / m ² ). The release liner (7) was prepared by the method. The obtained release liner (7) has a total basis weight of 140 g / m ² , a total thickness of 150 μm, a tensile strength in the flow direction of 68 N / 5 mm, and a tensile strength in the width direction of 47 N / 5 mm. The bending resistance in the direction was 3360 mg, the bending resistance in the width direction was 2580 mg, the tear strength in the flow direction was 1.5 N, and the peel load 1 (801B method) was 0.20 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (7) was prepared in the same manner as in Example 1 except that the release liner (7) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (7) was 36.8% by mass.

(Example 8)
Instead of a coating liquid in which an addition type silicone release agent (KS-847T), a heavy release additive (KS-3800) and a platinum catalyst (CAT-PL-50T) are mixed, an addition type silicone release agent [ Toray Dow Corning Co., Ltd., trade name: SRX345] 100 parts by mass of platinum catalyst [Toray Dow Corning Co., Ltd., trade name: SRX212] 1 part by mass, dissolved in toluene, solid content concentration A release liner (8) was prepared in the same manner as in Example 7 except that the coating liquid prepared to 5% by mass was used. The obtained release liner (8) has a total basis weight of 140 g / m ² , a total thickness of 150 μm, a tensile strength in the flow direction of 69 N / 5 mm, and a tensile strength in the width direction of 48 N / 5 mm. The bending resistance in the direction was 3400 mg, the bending resistance in the width direction was 2680 mg, the tear strength in the flow direction was 1.5 N, and the peel load 1 (801B method) was 0.28 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (8) was prepared in the same manner as in Example 1 except that the release liner (8) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (8) was 36.8% by mass.

Example 9
A release liner (9) was prepared in the same manner as in Example 4 except that polypropylene was used instead of polyethylene as the polyolefin layer. The obtained release liner (9) has a total basis weight of 127 g / m ² , a total thickness of 135 μm, a tensile strength in the flow direction of 61 N / 5 mm, and a tensile strength in the width direction of 52 N / 5 mm. The bending resistance in the direction was 3540 mg, the bending resistance in the width direction was 2700 mg, the tear strength in the flow direction was 0.7 N, and the peel load 1 (801B method) was 0.20 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (9) was prepared in the same manner as in Example 1 except that the release liner (9) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (9) was 36.8% by mass.

(Example 10)
A double-sided pressure-sensitive adhesive tape (10) was prepared in the same manner as in Example 2, except that the acrylic pressure-sensitive adhesive (2) obtained in Preparation Example 2 was used instead of the acrylic pressure-sensitive adhesive (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (10) was 37.4% by mass.

(Example 11)
A double-sided pressure-sensitive adhesive tape (11) was prepared in the same manner as in Example 4 except that the acrylic pressure-sensitive adhesive (2) obtained in Preparation Example 2 was used instead of the acrylic pressure-sensitive adhesive (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (11) was 37.4% by mass.

Example 12
A double-sided pressure-sensitive adhesive tape (12) was prepared in the same manner as in Example 2, except that the acrylic pressure-sensitive adhesive (3) obtained in Preparation Example 3 was used instead of the acrylic pressure-sensitive adhesive (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (12) was 36.5% by mass.

(Example 13)
A double-sided pressure-sensitive adhesive tape (13) was prepared in the same manner as in Example 4 except that the acrylic pressure-sensitive adhesive (3) obtained in Preparation Example 3 was used instead of the acrylic pressure-sensitive adhesive (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (13) was 36.5% by mass.

(Example 14)
A double-sided pressure-sensitive adhesive tape (14) was prepared in the same manner as in Example 2 except that the acrylic pressure-sensitive adhesive (4) obtained in Preparation Example 4 was used instead of the acrylic pressure-sensitive adhesive (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (14) was 37.0% by mass.

(Example 15)
A double-sided pressure-sensitive adhesive tape (15) was prepared in the same manner as in Example 2, except that the acrylic pressure-sensitive adhesive (5) obtained in Preparation Example 5 was used instead of the acrylic pressure-sensitive adhesive (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (14) was 37.0% by mass.

(Example 16)
Instead of the non-woven fabric, a PET film having a thickness of 16 μm [manufactured by Unitika Ltd., trade name: EMBLET SG16] was used, except that the thickness after drying of the acrylic adhesive (1) was changed from 65 μm to 62 μm. Prepared a double-sided pressure-sensitive adhesive tape (16) in the same manner as in Example 2. The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (16) was 36.8% by mass.

(Comparative Example 1)
A method similar to Example 1 except that high-quality paper [Nippon Paper Industries Co., Ltd., N / L material mixed, basis weight 73 g / m ² was used instead of high-quality paper (basis weight 78 g / m ² ). A release liner (H1) was prepared. The obtained release liner (H1) has a total basis weight of 122 g / m ² , a total thickness of 125 μm, a tensile strength in the flow direction of 34 N / 5 mm, and a tensile strength in the width direction of 22 N / 5 mm. The bending resistance in the direction was 1880 mg, the bending resistance in the width direction was 1000 mg, the tear strength in the flow direction was 0.6 N, and the peel load 1 (801B method) was 0.12 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (H1) was prepared in the same manner as in Example 1 except that the release liner (H1) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (H1) was 36.8% by mass.

(Comparative Example 2)
A method similar to Example 1 except that high-quality paper [Nippon Paper Industries Co., Ltd., N material / L material mixed, basic weight 65 g / m ² was used instead of high-quality paper (basis weight 78 g / m ² ) A release liner (H2) was prepared. The obtained release liner (H2) has a total basis weight of 105 g / m ² , a total thickness of 110 μm, a tensile strength in the flow direction of 32 N / 5 mm, and a tensile strength in the width direction of 20 N / 5 mm. The bending resistance in the direction was 1070 mg, the bending resistance in the width direction was 760 mg, the tear strength in the flow direction was 0.6 N, and the peel load 1 (801B method) was 0.12 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (H2) was prepared in the same manner as in Example 1 except that the release liner (H2) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (H2) was 36.8% by mass.

(Comparative Example 3)
The same method as in Example 1 except that high-quality paper [Nippon Paper Industries Co., Ltd., N / L material hybrid, basis weight 60 g / m ² was used instead of high-quality paper (basis weight 78 g / m ² ). A release liner (H3) was prepared. The obtained release liner (H3) has a total basis weight of 100 g / m ² , a total thickness of 100 μm, a tensile strength in the flow direction of 16 N / 5 mm, and a tensile strength in the width direction of 8 N / 5 mm. The bending resistance in the direction was 910 mg, the bending resistance in the width direction was 580 mg, the tear strength in the flow direction was 0.5 N, and the peel load 1 (801B method) was 0.13 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (H3) was prepared in the same manner as in Example 1 except that the release liner (H3) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (H3) was 36.8% by mass.

(Comparative Example 4)
100 mass of addition type silicone release agent [manufactured by Toray Dow Corning Co., Ltd., trade name: SRX345] instead of a coating liquid in which addition type silicone release agent (SD7333) and platinum catalyst (SRX212) are mixed. Comparative Example, except that 1 part by weight of platinum catalyst [trade name: SRX212] manufactured by Toray Dow Corning Co., Ltd. was added to the part, and a coating solution prepared by dissolving in toluene to a solid content concentration of 5% by weight was used. In the same manner as in Example 2, a release liner (H4) was prepared. The obtained release liner (H4) has a total basis weight of 105 g / m ² , a total thickness of 110 μm, a tensile strength in the flow direction of 32 N / 5 mm, and a tensile strength in the width direction of 21 N / 5 mm. The bending resistance in the direction was 1020 mg, the bending resistance in the width direction was 840 mg, the tear strength in the flow direction was 0.6 N, and the peel load 1 (801B method) was 0.40 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (H1) was prepared in the same manner as in Example 1 except that the release liner (H4) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (H1) was 36.8% by mass.

(Comparative Example 5)
100 mass of addition type silicone release agent [manufactured by Toray Dow Corning Co., Ltd., trade name: SRX345] instead of a coating liquid in which addition type silicone release agent (SD7333) and platinum catalyst (SRX212) are mixed. Comparative Example, except that 1 part by weight of platinum catalyst [trade name: SRX212] manufactured by Toray Dow Corning Co., Ltd. was added to the part, and a coating solution prepared by dissolving in toluene to a solid content concentration of 5% by weight was used. In the same manner as in Example 3, a release liner (H5) was prepared. The obtained release liner (H5) has a total basis weight of 100 g / m ² , a total thickness of 100 μm, a tensile strength in the flow direction of 17 N / 5 mm, and a tensile strength in the width direction of 9 N / 5 mm. The bending resistance in the direction was 980 mg, the bending resistance in the width direction was 620 mg, the tear strength in the flow direction was 0.5 N, and the peel load 1 (801B method) was 0.41 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (H5) was prepared in the same manner as in Example 1 except that the release liner (H5) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (H5) was 36.8% by mass.

(Comparative Example 6)
100 mass of addition type silicone release agent [manufactured by Toray Dow Corning Co., Ltd., trade name: SRX345] instead of a coating liquid in which addition type silicone release agent (SD7333) and platinum catalyst (SRX212) are mixed. 5 parts by weight of heavy release additive [BY24-843] and 1 part by weight of a platinum catalyst [manufactured by Toray Dow Corning Co., Ltd., trade name: SRX212], and dissolved in toluene to a solid content concentration of 5% by weight A release liner (H6) was prepared in the same manner as in Comparative Example 2 except that the coating liquid prepared in 1 was used.

  A double-sided pressure-sensitive adhesive tape (H6) was prepared in the same manner as in Example 1 except that the release liner (H6) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (H6) was 36.8% by mass.

(Comparative Example 7)
Addition type silicone release agent [Shin-Etsu Chemical Co., Ltd., trade name: KS-847T] 100 parts by mass, heavy release additive [Shin-Etsu Chemical Co., Ltd., trade name: KS-3800] 5 parts by mass 1 part by mass of a platinum catalyst [manufactured by Shin-Etsu Chemical Co., Ltd., trade name: CAT-PL-50T] was added and dissolved in toluene to prepare a coating solution having a solid content concentration of 5% by mass. On both sides of glassine paper [Oji Paper Co., Ltd., N material / L material mixed, basis weight 81 g / m ² ], the coating solution of the release agent is applied in a coating amount of 0.8 g / m 2 (solid content). Then, a silicone layer was formed by drying and curing at 100 ° C. for 5 minutes and curing in a 40 ° C. environment for 72 hours to obtain a release liner (H7). The obtained release liner (H7) has a total basis weight of 90 g / m ² , a total thickness of 90 μm, a tensile strength in the flow direction of 21 N / 5 mm, and a tensile strength in the width direction of 11 N / 5 mm. The bending resistance in the direction was 1750 mg, the bending resistance in the width direction was 910 mg, the tear strength in the flow direction was 0.6 N, and the peel load 1 (801B method) was 0.20 N / 20 mm.

  A double-sided pressure-sensitive adhesive tape (H7) was prepared in the same manner as in Example 1 except that the release liner (H7) was used instead of the release liner (1). The gel fraction of the pressure-sensitive adhesive layer constituting the double-sided pressure-sensitive adhesive tape (H7) was 36.8% by mass.

  The following table shows the results of the above evaluations on the release liner used in the examples and comparative examples, and the produced double-sided pressure-sensitive adhesive tape.

  As is clear from the above table, the double-sided pressure-sensitive adhesive tapes of the present invention shown in Examples 1 to 16 are excellent in adhesiveness to foam materials, the release load of the release liner is low, and the release liner is excellent in hand peeling suitability In the double-sided pressure-sensitive adhesive tapes shown in Comparative Examples 1 to 7, the release load of the release liner was high, and the results were poor in the ability to peel off the release liner.

DESCRIPTION OF SYMBOLS 1 Ether type polyurethane foam 2 Adhesive layer 3 Middle core base material 4 Release liner 5 Adhesive tape 6 Test piece 7

Claims (10)

An adhesive tape used for fixing a foam material, wherein the adhesive tape has an adhesive layer (B) formed using an aqueous adhesive composition on both sides of a core substrate (A), A release liner (C) is laminated on one or both sides of the pressure-sensitive adhesive layer (B),
The tensile strength in the flow direction of the release liner (C) measured by a tensile test at a speed of 20 m / min is 35 N / 5 mm or more, and the tensile strength in the width direction of the release liner (C) is 35 N / The release liner (C) measured in accordance with JIS L 1085 has a bending softness (Gurley method) of 1000 mg or more and a width of the release liner (C). Acrylic polymer , tackifying resin, and cross-linking obtained by polymerizing a monomer component in which the direction bending resistance (Gurley method) is 1000 mg or more and the pressure-sensitive adhesive layer (B) contains 2-ethylhexyl acrylate It has been formed using a water-based adhesive composition comprising a material, the content of the 2-ethylhexyl acrylate, based on the total amount of the monomer component used in the preparation of the acrylic polymer 0 is the mass% to 98 mass%, the adhesive tape the content of the tackifier resin is characterized in that the 10 to 35 parts by mass of the acrylic polymer 100 parts by weight. When the adhesive layer (B) has a 180-degree peeling adhesive strength to the foam material of 1.5 N / 20 mm or more, and the release liner (C) is peeled off from the adhesive layer (B). The pressure-sensitive adhesive tape according to claim 1, wherein the peeling force is 1 N / 20 mm or less. The pressure-sensitive adhesive tape according to claim 1 or 2, wherein the core substrate (A) is a nonwoven fabric having a thickness in the range of 20 µm to 80 µm. The pressure-sensitive adhesive layer (B) contains an acrylic polymer, and the acrylic polymer is a vinyl monomer having a nitrogen atom containing N-vinylpyrrolidone and a vinyl monomer having a carboxyl group. The pressure-sensitive adhesive tape according to claim 1, wherein the pressure-sensitive adhesive tape is obtained by polymerizing a monomer component containing a (meth) acrylate having an alkyl group having 4 to 8 carbon atoms. The pressure-sensitive adhesive tape according to any one of claims 1 to 4, wherein the pressure-sensitive adhesive layer (B) contains a tackifying resin not containing an aromatic organic solvent. The pressure-sensitive adhesive tape according to any one of claims 1 to 4, wherein the pressure-sensitive adhesive layer (B) contains a tackifying resin having a softening point in a range of 140 ° C to 180 ° C. The release liner (C) has a polyolefin layer having a thickness of 15 μm to 30 μm on one side or both sides of a base paper obtained using softwood bleached sulfate pulp and hardwood bleached sulfate pulp, The pressure-sensitive adhesive tape according to any one of claims 1 to 6, which has a silicone-containing layer on both sides. The pressure-sensitive adhesive tape according to claim 1, wherein the release liner (C) has a thickness of 100 μm to 200 μm. A foam material is affixed to one surface of the core substrate (A) via an adhesive layer (B1) formed using the aqueous pressure-sensitive adhesive composition, and the core substrate (A) On the other side, the pressure-sensitive adhesive layer (B2) formed using an aqueous pressure-sensitive adhesive composition and a release liner (C) are laminated, and a tensile test at a speed of 20 m / min. The tensile strength in the flow direction of the release liner (C) measured in the above is 35 N / 5 mm or more, the tensile strength in the width direction of the release liner (C) is 35 N / 5 mm or more, and JIS L 1085 Of the release liner (C) measured in conformity with the flow direction (Gurley method) is 1000 mg or more, and the flexibility (Gurley method) in the width direction of the release liner (C) is A laminated adhesive tape characterized by being 1000 mg or more. A method for producing a member, comprising: stacking one or more of the pressure-sensitive adhesive tape according to any one of claims 1 to 8 or the laminated pressure-sensitive adhesive tape according to claim 9 and cutting them by a press punching method. .

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