JPWO2016186045A1 - Adhesive tape and method for producing adhesive tape - Google Patents

Abstract

An object of this invention is to provide the adhesive tape which is excellent in heat resistance, and whose adhesive force does not advance easily also with time or high temperature, and the manufacturing method of this adhesive tape. The present invention is a pressure-sensitive adhesive tape having a base material layer and a pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer contains a styrene-based elastomer, and the gel fraction of the pressure-sensitive adhesive layer is 70% by weight or more. It is an adhesive tape.

Description

The present invention relates to a pressure-sensitive adhesive tape that is excellent in heat resistance and that does not easily develop an adhesive force even over time or at a high temperature, and a method for producing the pressure-sensitive adhesive tape.

Adhesive tapes are used in various industrial fields because they can be easily joined. Temporary fixing of curing sheets and bonding of interior materials in the construction field, fixing of interior parts such as seats and sensors, fixing of exterior parts such as side moldings and side visors in the automotive field, module assembly in the electrical and electronic field, Adhesive tape is used for attaching the module to the housing. For example, an adhesive tape is also used as a surface protective material for temporarily protecting the surface of a member such as an optical device, a metal plate, a painted metal plate, a resin plate, or a glass plate.

The adhesive tape is required to have various performances such as mechanical performance such as tensile strength and appropriate adhesive strength depending on the application. For example, in applications exposed to a high temperature environment, high heat resistance that does not decrease the adhesive strength even under the high temperature environment is important. Further, in the use as a surface protective material, performance (low adhesion progressing property) and the like that can be peeled without remaining adhesive without progressing adhesion even with lapse of time or at a high temperature is required.

As an adhesive tape excellent in heat resistance and low adhesive progress, an adhesive tape containing a silicone-based adhesive composition as an adhesive component is known (for example, Patent Document 1). However, conventional heat-resistant adhesive tapes are manufactured by a so-called coating method in which a solution in which an adhesive component is dissolved in an appropriate organic solvent is coated on a substrate and dried to form an adhesive layer. Was normal. The pressure-sensitive adhesive tape produced by such a coating method has a problem that the organic solvent remains in the pressure-sensitive adhesive layer and the adhesive remains.

JP 2003-96429 A

The present inventors examined using a styrene-type elastomer as an adhesive component which comprises the adhesive layer of an adhesive tape. The pressure-sensitive adhesive layer containing a styrene-based elastomer can exhibit high initial pressure-sensitive adhesive properties, and can be molded by lamination methods such as extrusion lamination and extrusion coating, and extrusion molding methods. Can be manufactured. However, the pressure-sensitive adhesive layer containing a styrene-based elastomer has poor heat resistance and has a problem that adhesion progresses over time or at high temperatures.

An object of the present invention is to provide a pressure-sensitive adhesive tape that has excellent heat resistance and does not easily develop adhesive strength even with time or at high temperatures, and a method for producing the pressure-sensitive adhesive tape.

The present invention is a pressure-sensitive adhesive tape having a base material layer and a pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer contains a styrene-based elastomer, and the gel fraction of the pressure-sensitive adhesive layer is 70% by weight or more. It is an adhesive tape.
The present invention is described in detail below.

As a result of intensive studies, the present inventors have found that the pressure-sensitive adhesive tape in which the gel fraction of the pressure-sensitive adhesive layer containing the styrene elastomer is adjusted to 70% by weight or more is excellent in heat resistance, and the pressure-sensitive adhesive strength is improved even with aging or high temperature. The present invention has been completed by finding that it has a low adhesion-enhancing property that is difficult to form.

The pressure-sensitive adhesive tape of the present invention has a base material layer and a pressure-sensitive adhesive layer.
The pressure-sensitive adhesive layer contains a styrene-based elastomer. By using a styrene-based elastomer as the adhesive component, an adhesive tape having excellent initial adhesiveness can be produced by an extrusion method that does not use an organic solvent.

In order to make the gel fraction of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive tape of the present invention 70% by weight or more, it is preferable to use a styrene-based elastomer having a polymerizable double bond as a styrene-based elastomer as a raw material. The styrenic elastomer having a polymerizable double bond is used as the styrenic elastomer, and after forming the pressure-sensitive adhesive layer by an extrusion molding method or the like, the styrene-based elastomer having a double bond is crosslinked to crosslink the gel content of the pressure-sensitive adhesive layer. The rate can be adjusted to 70% by weight or more.

The styrene-based elastomer having a polymerizable double bond is not particularly limited. For example, styrene-isoprene block copolymer (SI), styrene-isoprene-styrene block copolymer (SIS), styrene-butadiene block copolymer Copolymer (SB), styrene-butadiene-styrene block copolymer (SBS), partially hydrogenated styrene-ethylenebutylene-styrene block copolymer (partially hydrogenated SEBS), partially hydrogenated styrene-ethylenepropylene-styrene block copolymer Examples include coalescence (partially hydrogenated SEPS).

The pressure-sensitive adhesive layer may contain a resin other than the styrene-based elastomer having a polymerizable double bond as a raw material.
The other resins are not particularly limited, and are polymerizable such as hydrogenated styrene-ethylenebutylene-styrene block copolymer (hydrogenated SEBS) and hydrogenated styrene-ethylenepropylene-styrene block copolymer (hydrogenated SEPS). Styrenic elastomers that do not have double bonds, non-styrenic elastomers that have polymerizable double bonds such as syndiotactic 1,2-polybutadiene (RB), polyethylene (PE), polybutene, and ethylene-propylene copolymers And olefin resins having no polymerizable double bond such as ethylene-butene copolymer and propylene-butene copolymer.

When the said adhesive layer contains other resin, it is preferable that content of the styrene-type elastomer which has the said polymerizable double bond which occupies for the whole elastomer is 60 weight% or more. By setting the content of the styrenic elastomer having a polymerizable double bond to 60% by weight or more, the gel fraction of the pressure-sensitive adhesive layer can be easily adjusted to 70% by weight or more. The content of the styrenic elastomer having a polymerizable double bond is more preferably 70% by weight or more, and may be 100% by weight.

The pressure-sensitive adhesive layer may further contain a tackifier.
The tackifier is not particularly limited. For example, petroleum resins such as aliphatic copolymers, aromatic copolymers, aliphatic aromatic copolymers, and alicyclic copolymers, coumarone-indene resins, Examples thereof include terpene resins, terpene phenol resins, rosin resins such as polymerized rosin, (alkyl) phenol resins, xylene resins and the like.
The hydrogenation rate of the tackifier is not particularly limited, and any of non-hydrogenated products, partially hydrogenated products, fully hydrogenated products, and the like can be used.
Moreover, you may use the tackifier marketed as a mixture with polyolefin resin. These tackifiers may be used alone or in combination of two or more.

Although content of the said tackifier is not specifically limited, The preferable upper limit with respect to 100 weight part of said elastomer components is 50 weight part. When the content of the tackifier exceeds 50 parts by weight, the tackifier may bleed out from the pressure-sensitive adhesive layer. The upper limit with more preferable content of the said tackifier is 40 weight part.

The pressure-sensitive adhesive layer preferably contains a photopolymerization initiator when light irradiation is performed when the gel fraction of the pressure-sensitive adhesive layer described later is adjusted to 70% by weight or more.
The photopolymerization initiator is not particularly limited. For example, a benzophenone compound, an acetophenone compound, an acylphosphine oxide compound, a titanocene compound, an oxime ester compound, a benzoin ether compound, a thioxanthone, or the like is preferably used. it can.

The said adhesive layer may contain a mold release agent in the range which does not inhibit the effect of this invention. By including a release agent, for example, when used for a surface protective material, it is possible to further prevent adhesive residue at the time of peeling. It does not specifically limit as said mold release agent, A conventionally well-known mold release agent can be used.
When the said adhesive layer contains a mold release agent, the preferable upper limit of content of a mold release agent with respect to 100 weight part of said elastomer components is 0.5 weight part. When the content of the release agent exceeds 0.5 parts by weight, the release agent may bleed out from the pressure-sensitive adhesive layer and may contaminate the surface of the adherend.

The pressure-sensitive adhesive layer may contain conventionally known additives such as a softening agent, an antioxidant, and an adhesion progressing prevention agent, if necessary.

The pressure-sensitive adhesive layer has a gel fraction of 70% by weight or more. By setting the gel fraction of the pressure-sensitive adhesive layer to 70% by weight or more, the pressure-sensitive adhesive tape of the present invention can exhibit high heat resistance, and has low adhesion enhancing property in which the adhesive force is difficult to increase even with aging or high temperature. Can demonstrate. As for the gel fraction of the said adhesive layer, it is more preferable that it is 75 weight% or more, and it is still more preferable that it is 80 weight% or more. Although the upper limit of the gel fraction of the said adhesive layer is not specifically limited, In order to ensure favorable initial stage adhesive force, it is preferable that the gel fraction of the said adhesive layer is 98 weight% or less.
The gel fraction is measured as follows. First, only the pressure-sensitive adhesive layer is taken out from the pressure-sensitive adhesive tape, cut into a plane rectangular shape of about 50 mm × 100 mm to produce a test piece, the test piece is immersed in toluene at 23 ° C. for 24 hours, and then taken out from toluene. , And dried at 110 ° C. for 1 hour. The weight of the test piece after drying is measured, and the gel fraction is calculated using the following formula (1). In addition, the release film for protecting an adhesive layer shall not be laminated | stacked on the test piece.
Gel fraction (% by weight) = (W2 / W1) × 100 (1)
(W1: Weight of test piece before immersion, W2: Weight of test piece after immersion and drying)
When a sufficient sample amount cannot be secured, only the pressure-sensitive adhesive layer is taken out from the pressure-sensitive adhesive tape, and a test piece cut into a plane rectangular shape of about 5 mm × 10 mm may be used for the measurement of the gel fraction.

The pressure-sensitive adhesive layer preferably has a temperature of 130 ° C. or higher when the storage elastic modulus E ′ is 1.0 × 10 ⁵ Pa. Thereby, when it affixes on a to-be-adhered body, it can suppress more that adhesion progress advances with time or high temperature. The temperature at which the storage elastic modulus E ′ of the pressure-sensitive adhesive layer is 1.0 × 10 ⁵ Pa is more preferably 135 ° C. or higher.

The pressure-sensitive adhesive layer preferably has a storage elastic modulus E ′ at 150 ° C. of 6.0 × 10 ⁵ Pa or more. Thereby, when it affixes on a to-be-adhered body, it can suppress more that adhesion progress advances with time or high temperature.

In addition, the storage elastic modulus E ′ of the pressure-sensitive adhesive layer is, for example, a condition of 10 ° C./min and 10 Hz in a constant speed temperature rising tension mode using a viscoelastic spectrometer such as DVA-200 (manufactured by IT Measurement & Control Co., Ltd.). It can obtain | require by measuring the dynamic viscoelastic spectrum of the said adhesive layer.

A method of adjusting the temperature when the storage elastic modulus E ′ of the pressure-sensitive adhesive layer becomes 1.0 × 10 ⁵ Pa to 130 ° C. or more, and the storage elastic modulus E ′ at 150 ° C. of 6.0 × 10 ⁵ Pa Although it does not specifically limit as a method adjusted above, For example, the method of bridge | crosslinking an adhesive layer etc. are mentioned.

The thickness of the pressure-sensitive adhesive layer is not particularly limited as long as it is appropriately set depending on the application, but a preferable lower limit is 2 μm and a preferable upper limit is 30 μm. When the thickness of the pressure-sensitive adhesive layer is less than 2 μm, sufficient initial adhesive strength may not be exhibited. When the thickness exceeds 30 μm, the adhesive strength increases, and for applications that require peeling of surface protective materials, for example. May not be suitable. The minimum with more preferable thickness of the said adhesive layer is 3 micrometers, and a more preferable upper limit is 20 micrometers.

Although the said base material layer is not specifically limited, It is preferable to contain polyolefin resin.
The polyolefin resin is not particularly limited, and a conventionally known polyolefin resin can be used, and examples thereof include polypropylene (PP) and polyethylene (PE).
Examples of the polypropylene include homopolypropylene, random polypropylene, and block polypropylene.
Examples of the polyethylene include high pressure method low density polyethylene, linear low density polyethylene, and high density polyethylene.
Especially, when performing electron beam irradiation when adjusting the gel fraction of the adhesive layer mentioned later to 70 weight% or more, the base material layer which consists of block polypropylene and / or polyethylene is suitable. The base material layer made of block polypropylene and / or polyethylene is not easily embrittled even when irradiated with an electron beam, and can maintain a high tensile strength.

The base material layer is within the range not impairing the effects of the present invention, additives such as antistatic agents, mold release agents, antioxidants, weathering agents, crystal nucleating agents, resins such as polyolefin, polyester, polyamide, elastomer, You may contain a modifier.

Although the thickness of the said base material layer should just be suitably set with an application, it is not specifically limited, A preferable minimum is 25 micrometers and a preferable upper limit is 200 micrometers. When the thickness of the base material layer is less than 25 μm, the adhesive tape is weak and may be inferior in handleability. When the thickness exceeds 200 μm, winding may be left when the film is wound and stored. . The minimum with more preferable thickness of the said base material layer is 30 micrometers, and a more preferable upper limit is 150 micrometers.

When the pressure-sensitive adhesive tape of the present invention is adhered to the corona-treated surface of a corona-treated plastic film on the surface and left to stand at 40 ° C. for 24 hours, the adhesive tape is peeled off before and after the adhesion. It is preferable that the rate of change of the surface tension of the corona-treated surface of the plastic film is 35% or less. When the surface of the adherend is contaminated and the surface tension is reduced, when an adhesive or hard coat agent is applied to the surface of the adherend after peeling the adhesive tape, minute application unevenness occurs, When assembled into a product, brightness and color unevenness may occur. The rate of change of the surface tension can be adjusted, for example, by adjusting the amount of release agent added to the pressure-sensitive adhesive layer.

The method for producing the pressure-sensitive adhesive tape of the present invention is not particularly limited. For example, after preparing a laminate in which an unadjusted pressure-sensitive adhesive layer whose gel fraction is not adjusted is prepared on the base material layer, the unadjusted pressure-sensitive adhesive is prepared. Examples include a method of adjusting the gel fraction of the agent layer.
A method for producing a pressure-sensitive adhesive tape having a base material layer and a pressure-sensitive adhesive layer containing a styrene-based elastomer, wherein the gel fraction of the pressure-sensitive adhesive layer is 70% by weight or more, on the base material layer The process of preparing the laminated body which laminated | stacked the unadjusted adhesive layer which is not adjusting the gel fraction, and irradiating an active energy ray to the unadjusted adhesive layer which is not adjusting the gel fraction of the said laminated body In addition, a method for producing an adhesive tape having a step of setting the gel fraction of the adhesive layer to 70% by weight or more is also one aspect of the present invention.

As a method for preparing the laminate, for example, a co-extrusion molding method in which each material of the base material layer and the pressure-sensitive adhesive layer is supplied to a multilayer extruder and molded, or by T-die molding or inflation molding in advance is obtained. A method of laminating an unadjusted pressure-sensitive adhesive layer by a known laminating method such as extrusion lamination or extrusion coating on the obtained base material layer, or making each layer an independent film, The method of laminating by dry lamination is mentioned. Of these, the coextrusion method is preferred from the viewpoint of productivity.

The method for adjusting the gel fraction is not particularly limited, but when the unadjusted pressure-sensitive adhesive layer contains a styrene elastomer having the polymerizable double bond, irradiation with active energy rays such as an electron beam and light is performed. A method of crosslinking the styrenic elastomer having a polymerizable double bond is mentioned. Among them, the method of irradiating with an electron beam is preferable because it is not necessary to use a photopolymerization initiator in combination and the reaction rate is fast and the initial gel fraction can be achieved in a short time.

The method for irradiating the electron beam is not particularly limited. For example, the unadjusted pressure-sensitive adhesive layer of the laminate may be applied using a commercially available electron beam irradiation device such as an area beam type curetron R manufactured by NHV Corporation. The method of irradiating light is mentioned.
The electron beam irradiation conditions may be appropriately set depending on the type and content of the styrenic elastomer having a polymerizable double bond, but conditions of an acceleration voltage of 50 to 1000 kV and a dose of about 0.5 to 10 Mrad are preferable. It is.

Since the pressure-sensitive adhesive tape of the present invention can be easily produced by a production method that does not use an organic solvent such as an extrusion molding method, the problem of residual organic solvent can be solved. Further, by adjusting the gel fraction of the pressure-sensitive adhesive layer to 70% by weight or more, it is possible to exhibit heat resistance and low adhesion enhancement property in which the adhesive force is difficult to progress even with time or high temperature.
The adhesive tape of this invention can be used especially suitably for the use exposed to a high temperature environment. Moreover, even if it sets to comparatively high initial adhesive force, since it can peel without adhesive adhesion progressing over time or under high temperature, and it can peel without adhesive residue, it can be used suitably also as a surface protection material. For example, optical members for liquid crystal displays such as prism sheets (also referred to as brightness enhancement films) and diffusion films have a concavo-convex shape on the surface. If the pressure-sensitive adhesive tape of the present invention is used, the surface of such concavo-convex shape has a high initial value. Even if it is applied with an adhesive force, the adhesive force is unlikely to increase even with lapse of time or at a high temperature, so that it can be easily peeled without any adhesive residue.

ADVANTAGE OF THE INVENTION According to this invention, it is excellent in heat resistance, and can provide the manufacturing method of this adhesive tape and the adhesive tape which adhesive force does not advance easily with time or high temperature.

Hereinafter, embodiments of the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

Example 1
As a raw material for the pressure-sensitive adhesive layer, a tackifier (trade name “Arcon P125”, manufactured by Arakawa Chemical Industries, Ltd., fat, with respect to 100 parts by weight of the resin A shown in Table 1 which is a styrene elastomer having a polymerizable double bond. 5 parts by weight of a cyclic saturated hydrocarbon resin) and 1 part by weight of an antioxidant (trade name “IRGANOX 1010”, manufactured by BASF) were blended to obtain a pressure-sensitive adhesive composition for forming a pressure-sensitive adhesive layer.
As raw materials for the base material layer, 80 parts by weight of block polypropylene (trade name “J715M”, manufactured by Prime Polymer Co., Ltd.) and 20 parts by weight of low density polyethylene (trade name “L2340”, manufactured by Asahi Kasei Co., Ltd.) were mixed.
Co-extrusion molding was performed by a T-die method to obtain a laminate having a base material layer thickness of 55 μm and an uncrosslinked pressure-sensitive adhesive layer thickness of 5 μm.

From the uncrosslinked pressure-sensitive adhesive layer side of the obtained laminate, an electron beam was irradiated using an electron beam irradiation apparatus (trade name “Area Beam Method, Curetron R”, manufactured by NHV Corporation) under conditions of an acceleration voltage of 500 kV and a dose of 5 Mrad. Was irradiated. It was 75 weight% when the gel fraction was measured about the adhesive layer of the adhesive tape after electron beam irradiation.

Moreover, about the adhesive layer of the adhesive tape after electron beam irradiation, using a viscoelasticity spectrometer (made by IT measurement control company, DVA-200), 10 degree-C / min and 10 Hz conditions of constant-speed temperature rising tension mode. When the storage elastic modulus E ′ was determined by measuring the dynamic viscoelastic spectrum, the temperature at which the storage elastic modulus E ′ was 1.0 × 10 ⁵ Pa was 145 ° C. or higher, and the storage elastic modulus E ′ at 150 ° C. Was 8 × 10 ⁵ Pa.

(Examples 2-6, Comparative Examples 1-6, Reference Example 1)
A pressure-sensitive adhesive tape was obtained in the same manner as in Example 1 except that the raw materials for the pressure-sensitive adhesive layer and the base material layer and the electron beam irradiation conditions were as shown in Tables 1 and 2.
In addition, ethylene bis-stearic acid amide (the product name "Alflow H50F" by NOF Corporation) was used as a mold release agent.

<Evaluation>
The following evaluation was performed about the adhesive tape obtained by the Example, the comparative example, and the reference example. The results are shown in Table 2.

(1) Evaluation of initial adhesive force A prism sheet (a diffusing film whose matte surface is an acrylic film having an arithmetic average roughness Ra (JIS B 0601-1994) of 0.32 μm) was prepared as an adherend. A 25 mm wide adhesive tape was affixed to cover the mat surface of the adherend to prepare a test piece. The pasting was performed by pressing at a speed of 300 mm / min using a 2 kg pressure-bonded rubber roller in an environment of 23 ° C. and a relative humidity of 50% RH. The obtained test piece was left for 30 minutes in an environment of 23 ° C. and a relative humidity of 50% RH. After standing, the adhesive tape was peeled from the adherend in a 180 ° direction at a tensile speed of 300 mm / min in accordance with JIS Z0237, and the initial adhesive force was measured. Further, the initial adhesive strength was determined according to the following criteria.
A: 0.15 N / 25 mm or more, less than 0.3 N / 25 mm B: 0.1 N / 25 mm or more, less than 0.15 N / 25 mm, or 0.3 N / 25 mm or more, less than 0.4 N / 25 mm. Less than 1N / 25mm, or 0.4N / 25mm or more

(2) Evaluation of Adhesion Progression Rate A prism sheet (a diffusing film whose matte surface is an acrylic film having an arithmetic average roughness Ra (JIS B 0601-1994) of 0.32 μm) was prepared as an adherend. A 25 mm wide adhesive tape was affixed to cover the mat surface of the adherend to prepare a test piece. Pasting was performed by laminating at a speed of 300 mm / min using a 2 kg pressure-bonded rubber roller in an environment of 23 ° C. and a relative humidity of 50% RH. The obtained test piece was left in a temperature environment of 50 ° C. for 168 hours. After standing, the test piece was taken out to room temperature and left for another 60 minutes, and then the adhesive tape was peeled off from the adherend in a 180 ° direction at a tensile speed of 300 mm / min in accordance with JIS Z0237, and the adhesive strength with time was measured. .
Using the initial adhesive force and the temporal adhesive force obtained by the above formula (1), the rate of change from the initial adhesive force to the temporal adhesive force (adhesion progress rate) was calculated by the following equation.
Rate of change (adhesion progress rate) (%) = (adhesive force with time / initial adhesive force) × 100

Moreover, the adhesive strength with time was determined according to the following criteria.
◎: 150% or less ○: Over 150% and less than 200% ×: 200% or more

(3) Evaluation of heat resistance The produced adhesive tape was affixed on the stainless steel plate, a 200-g load was applied with respect to the adhesive surface, and 120 degreeC holding time was measured. Moreover, the heat resistance was determined according to the following criteria.
◎: More than 30 minutes ○: More than 5 minutes and less than 30 minutes ×: Less than 5 minutes

(4) Evaluation of surface tension of adherend surface after peeling The prepared adhesive tape was applied to a corona-treated polyethylene terephthalate (PET) film at room temperature of 23 ° C. and a relative humidity of 50% using a 2 kg pressure-bonded rubber roller. Affixed at a speed of 300 mm / min. In this state, it was left in an oven at 40 ° C. for 24 hours. After taking out to room temperature and leaving for 60 minutes, the adhesive tape was peeled off.
The surface tension of the surface of the PET film before and after peeling is measured based on the method specified in JIS K6768 using the wet tension test mixture, and the surface tension reduction rate is calculated by the following formula. And evaluated according to the following criteria.
Surface tension reduction rate = (1− (surface tension after peeling / surface tension before sticking)) × 100
○: Surface tension reduction rate is 35% or less ×: Surface tension reduction rate exceeds 35%

(5) Evaluation of tensile strength 10 mm of the produced adhesive tape was cut out, and the tensile strength was measured at a speed of 300 mm / min using a Tensilon universal testing machine (trade name “RTF-1210”, manufactured by A & D). . Moreover, the tensile strength was determined according to the following criteria.
A: 40 MPa or more B: 30 MPa or more, less than 40 MPa x: less than 30 MPa

ADVANTAGE OF THE INVENTION According to this invention, it is excellent in heat resistance, and can provide the manufacturing method of this adhesive tape and the adhesive tape which adhesive force does not advance easily with time or high temperature.

Claims (5)

A pressure-sensitive adhesive tape having a base material layer and a pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer contains a styrene elastomer, and the gel fraction of the pressure-sensitive adhesive layer is 70% by weight or more. Adhesive tape. The adhesive tape according to claim 1, wherein the adhesive layer has a storage elastic modulus E ′ at 150 ° C. of 6.0 × 10 ⁵ Pa or more. When an adhesive tape is stuck on the corona-treated surface of a corona-treated plastic film and the adhesive tape is peeled off after standing at 40 ° C. for 24 hours, the corona treatment of the plastic film before and after sticking The pressure-sensitive adhesive tape according to claim 1 or 2, wherein the surface tension change rate of the surface is 35% or less. The pressure-sensitive adhesive tape according to claim 1, 2 or 3, wherein the base material layer is made of block polypropylene and / or polyethylene. A method for producing a pressure-sensitive adhesive tape having a base material layer and a pressure-sensitive adhesive layer containing a styrene-based elastomer, wherein the pressure-sensitive adhesive layer has a gel fraction of 70% by weight or more,
A step of preparing a laminate in which an unadjusted pressure-sensitive adhesive layer in which the gel fraction is not adjusted is laminated on the base material layer;
Irradiating active energy rays to an unadjusted pressure-sensitive adhesive layer in which the gel fraction of the laminate is not adjusted, and having a gel fraction of the pressure-sensitive adhesive layer of 70% by weight or more Manufacturing method of adhesive tape.