JP2009084367A - Double-sided adhesive tape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a double-sided adhesive tape that comprises a polyethylene foam as a base material and exhibits excellent adhesive force in both high-temperature environment and low-temperature environment. <P>SOLUTION: The double-sided adhesive tape comprising a polyethylene foam as a base material has an adhesive layer, composed of an acrylic adhesive containing an acrylic copolymer and a tackifier resin having a different softening point in a certain ratio, and a polyethylene foam having a low shrinkage ratio even at 90°C and therefore exhibits excellent adhesive force in both low-temperature environment and high-temperature environment. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a double-sided pressure-sensitive adhesive tape that is used for applications in which the external environment changes greatly, such as in the automobile field.

  Double-sided pressure-sensitive adhesive tapes based on foam are widely used for fixing plastic molded products for automobiles, home appliances, and OA equipment. In this application, the double-sided pressure-sensitive adhesive tape is required to follow the cubic curved surface of the molded product, the uneven surface processed into an embossed shape, etc., and to exhibit a high adhesive force. In particular, fixing parts of automobiles requires that the adhesive strength be stable throughout the season from the high temperature in summer to the low temperature in winter.

  It is disclosed that a double-sided pressure-sensitive adhesive tape having a foam as a base material is provided with independent foam having an elliptical cross section extending in parallel with the length direction of the foam. However, since the foam is stretched in the length direction with a hot roll in order to obtain an elliptical foam structure, the foam greatly contracts at a high temperature of about 90 ° C., and the interlayer strength also decreases. .

  On the other hand, an acrylic foam-based adhesive tape in which glass microbubbles are dispersed is also disclosed (Patent Document 2). However, acrylic foam pressure-sensitive adhesive tapes have poor conformability to uneven surfaces at low temperatures, resulting in reduced adhesive strength.

Japanese Patent Laid-Open No. 7-90932 Japanese Patent Publication No.57-17030

  An object of the present invention is to provide a double-sided pressure-sensitive adhesive tape based on a polyethylene foam having excellent adhesive strength in both high and low temperature environments.

  In the present invention, in a double-sided pressure-sensitive adhesive tape based on a polyethylene foam, a pressure-sensitive adhesive layer comprising an acrylic pressure-sensitive adhesive containing a certain proportion of an acrylic copolymer and a tackifying resin having a different softening point; By having a polyethylene foam having a low shrinkage even underneath, it is possible to realize a double-sided adhesive tape having excellent adhesive force even in both low and high temperature environments.

  That is, the present invention is a double-sided pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer made of an acrylic pressure-sensitive adhesive containing an acrylic copolymer and a tackifier resin, and a base material made of polyethylene foam, the acrylic pressure-sensitive adhesive. The content of the tackifying resin in the resin is 10 to 25 parts by mass with respect to 100 parts by mass of the acrylic copolymer, and as the tackifying resin, a rosin resin (a) having a softening point of 80 ° C. or higher and lower than 120 ° C. And a rosin resin (b) having a softening point of 120 ° C. or higher and 200 ° C. or lower, the mass ratio (a) / (b) of the two is 1/3 to 3/1, and the base material is 90 The present invention provides a double-sided pressure-sensitive adhesive tape characterized by being a base material having a heat shrinkage area ratio of 15% or less after standing for 22 hours at a temperature of ° C.

  Since the double-sided pressure-sensitive adhesive tape of the present invention has excellent adhesive strength under both high temperature and low temperature environments, it can be suitably used for applications in which a large temperature change is assumed, for example, for fixing automobile parts.

The present invention is a double-sided pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer made of an acrylic pressure-sensitive adhesive containing an acrylic copolymer and a tackifier resin, and a base material made of polyethylene foam. The content of the tackifier resin is 10 to 25 parts by mass with respect to 100 parts by mass of the acrylic copolymer, and as the tackifier resin, a polymerized rosin ester resin (a) having a softening point of 80 ° C. or higher and lower than 120 ° C. It contains a polymerized rosin ester resin (b) having a softening point of 120 ° C. or more and 200 ° C. or less, the mass ratio (a) / (b) of the two is 1/3 to 3/1, and the substrate is 90 ° C. The double-sided pressure-sensitive adhesive tape is characterized in that the substrate has a heat shrinkage area ratio of 15% or less before and after standing at a temperature of 22 hours.

[Adhesive layer]
(Acrylic copolymer)
The pressure-sensitive adhesive layer in the double-sided pressure-sensitive adhesive tape of the present invention is a layer made of a pressure-sensitive adhesive obtained by removing a solvent from an acrylic pressure-sensitive adhesive composition containing an acrylic copolymer and a tackifier resin. The acrylic copolymer is a resin obtained by copolymerizing a vinyl monomer having a functional group that reacts with (meth) acrylate and a crosslinking agent.

  As a monomer component constituting the acrylic copolymer, (meth) acrylate generally used for an adhesive can be used, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate. , Isobutyl (meth) acrylate, t-butyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl methacrylate and the like These 1 type (s) or 2 or more types are used. Among them, (meth) acrylates having 4 to 18 carbon atoms in the alkyl group, particularly n-butyl acrylate and 2-ethylhexyl acrylate are preferable, and both the adhesive force and the cohesive force are easily in a favorable range. Is preferably used in an amount of 80 to 98% by mass, more preferably 90 to 98% by mass, in the monomer component constituting the acrylic copolymer.

  The acrylic copolymer used in the present invention may be copolymerized with a highly polar vinyl monomer. Examples of the highly polar vinyl monomer include a monomer having a hydroxyl group, a monomer having a carboxyl group, and a monomer having an amino group. It is done. Examples of the monomer having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and the monomers having a carboxyl group include acrylic acid, methacrylic acid, Itaconic acid, maleic acid, (meth) acrylic acid dimer, crotonic acid, and the like include monomers having amino groups such as N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorpholine, dimethylaminoethyl acrylate, acrylamide, N, N-dimethylacrylamide and the like. Other examples include sulfonic acid group-containing monomers such as vinyl acetate, ethylene oxide-modified succinic acid acrylate, and 2-acrylamido-2-methylpropanesulfonic acid.

  The content of the highly polar vinyl monomer is preferably 1 to 15% by mass in the monomer component constituting the acrylic copolymer, more preferably 1.5 to 10% by mass, and 2 to 8% by mass. More preferably. If the highly polar vinyl monomer component is less than 1% by mass, the cohesive strength of the pressure-sensitive adhesive is lowered, and the holding power at high temperatures is deteriorated. On the other hand, if the content exceeds 15% by mass, the adhesive property at the initial stage or at low temperatures is deteriorated.

  The vinyl monomer having a functional group that reacts with the crosslinking agent used in the production of the acrylic copolymer resin is appropriately selected from the above high-polarity vinyl monomers depending on the type of the crosslinking agent. The copolymerization ratio of the vinyl monomer having a functional group that reacts with the crosslinking agent in the acrylic pressure-sensitive adhesive composition is preferably 0.01 to 2.0% by mass. More preferably, it is 0.03-1.5 mass%, More preferably, it is 0.05-1.0 mass%. If the content is less than 0.01% by mass, the crosslinking degree may be insufficient or uneven when crosslinked with a crosslinking agent, and thus the holding power at high temperatures may deteriorate. On the other hand, if it exceeds 2.0% by mass, it is difficult to control the degree of crosslinking when crosslinking is performed with a crosslinking agent, and the degree of crosslinking may increase with time and the initial adhesive strength may be reduced.

  The acrylic copolymer can be obtained by copolymerization by a known polymerization method such as a solution polymerization method, a cage polymerization method, a suspension polymerization method, or an emulsion polymerization method. Polymerization can be initiated by peroxides such as benzoyl peroxide and lauroyl peroxide, thermal initiation using azo-based thermal polymerization initiators such as azobisisobutylnitrile, acetophenone-based, benzoin ether-based, benzyl A starting method by ultraviolet irradiation using a ketal-based, acylphosphine oxide-based, benzoin-based or benzophenone-based photopolymerization initiator, or a method by electron beam irradiation can be arbitrarily selected.

(Tackifying resin)
In the present invention, a rosin resin (a) having a softening point of 80 ° C. or more and less than 120 ° C. and a rosin resin (b) having a softening point of 120 ° C. or more and 200 ° C. or less as a tackifier resin, a) / (b) is contained in a ratio of 1/3 to 3/1, preferably 1/2 to 3/1, preferably 1/2 to 2.5 / 1. By setting it as the said range, it becomes an adhesive excellent in the balance of the adhesive force in low temperature, and the retention strength in high temperature.

  Examples of the rosin resin include rosin resins, rosin ester resins, disproportionated rosin resins, polymerized rosin resins, polymerized rosin ester resins, and rosin phenol resins. Among these, a polymerized rosin ester resin can be preferably used for both the rosin resins (a) and (b). The rosin resin has a softening point of 120 ° C. or higher and 200 ° C. or lower in order to develop excellent adhesive strength under both high temperature and low temperature environments. The total content of the polymerized rosin ester resin (b) is preferably 10 to 25 parts by mass, more preferably 12 to 23 parts by mass with respect to 100 parts by mass of the acrylic copolymer. When the content of the pressure-sensitive adhesive resin is less than 10 parts by mass with respect to 100 parts by mass of the acrylic copolymer, the adhesiveness to the polyolefin resin is insufficient, and when it exceeds 25 parts by mass, the initial adhesiveness or Adhesiveness at low temperatures decreases.

(Crosslinking agent)
In the pressure-sensitive adhesive tape of the present invention, it is preferable to add a crosslinking agent in order to improve the cohesive strength of the pressure-sensitive adhesive. As the crosslinking agent in the pressure-sensitive adhesive composition, known polyisocyanates, epoxy resins, aziridine compounds, polyvalent metal salts, metal chelates, organic peroxides, and the like can be used. In consideration of the balance of heat resistance, peel resistance, and initial and low temperature adhesiveness, a polyisocyanate crosslinking agent is preferable. Examples of the polyisocyanate-based crosslinking agent include tolylene diisocyanate, naphthylene-1,5-diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, trimethylolpropane-modified tolylene diisocyanate, and the like. Particularly preferred are trifunctional polyisocyanate compounds. Examples of the trifunctional isocyanate compound include tolylene diisocyanate, trimethylolpropane adducts thereof, and triphenylmethane isocyanate.

  As an index of the degree of cross-linking, the value of the gel fraction for measuring the insoluble content after the pressure-sensitive adhesive layer is immersed in toluene for 24 hours is used. The gel fraction is preferably 20 to 50% by mass. More preferably, it is 25-45 mass%. When it is less than 20% by mass, the cohesive force is lowered and the holding power at high temperature is deteriorated. When it exceeds 50 mass%, the adhesiveness in the initial stage and under low temperature and the resilience resistance when pasted on a curved surface part are lowered.

(Loss tangent)
The loss tangent of the dynamic viscoelastic spectrum at a frequency of 1 Hz of the pressure-sensitive adhesive layer used in the pressure-sensitive adhesive tape of the present invention is preferably 0.4 to 0.6 at 95 ° C., 0.45 to 0.00. More preferably, it is 55. By setting the loss tangent within the above range, the cohesive force of the pressure-sensitive adhesive at 90 ° C. is not significantly impaired, and a good holding force can be obtained.

  The peak temperature of the loss tangent is preferably -20 to 0 ° C. By setting it as the said range, it becomes an adhesive excellent in the balance of adhesive force and holding power under both low temperature and high temperature conditions.

  The dynamic viscoelasticity of the pressure-sensitive adhesive layer in the present invention is obtained by sandwiching a test piece between parallel disks, which are measuring parts of the tester, using a viscoelasticity tester (manufactured by Rheometrics, trade name: Ares 2KSTD). Then, the storage elastic modulus (G ′) and the loss elastic modulus (G ″) at a frequency of 1 Hz are measured, and the loss tangent is calculated by an expression represented by tan δ = (G ″) / (G ′). The test piece uses an adhesive having a thickness of 0.5 to 2.5 mm.

[Base material]
The polyethylene foam used as the base material of the double-sided pressure-sensitive adhesive tape uses a foam having a heat shrinkage area ratio of 15% or less before and after standing at a temperature of 90 ° C. for 22 hours. When the heat shrinkage area ratio exceeds 15%, the adhesive strength and holding strength at high temperatures are reduced.

  The polyethylene foam preferably has a thickness of 0.1 mm to 1.5 mm.

  Furthermore, the apparent density of the polyethylene foam is preferably 0.1 to 0.3 g / cc. More preferably, it is 0.08-0.0.19 g / cc. When the apparent density is less than 0.1 g / cc, the interlayer strength of the foam is low, and when it exceeds 0.3 g / cc, the flexibility of the foam is lowered and the followability to the uneven surface is lowered.

  Further, the cutting strength of the polyethylene foam at 90 ° C. is preferably 0.5 MPa or more, more preferably 1 to 1.5 MPa. Moreover, it is preferable that elongation at the time of cutting | disconnection under 23 degreeC is 200% or more, and it is more preferable that it is 300 to 600%. The 25% compressive strength is preferably 0.2 MPa or less, more preferably 0.1 to 0.01 MPa.

  Polyethylene foam having such characteristics can be obtained by blending a chemical foaming agent, a color pigment, etc. into a polyethylene resin and then forming a sheet with a T-die, followed by cross-linking with an electron beam, followed by heating and foaming. It is not limited. Further, the polyethylene foam is preferably subjected to a surface treatment by corona discharge in order to improve the adhesion with the acrylic pressure-sensitive adhesive.

[Double-sided adhesive tape]
The double-sided pressure-sensitive adhesive tape of the present invention has a structure in which pressure-sensitive adhesive layers are provided on both surfaces of the substrate, and at least one of the pressure-sensitive adhesive layers, preferably both are pressure-sensitive adhesive layers comprising the acrylic pressure-sensitive adhesive composition. This is a double-sided adhesive tape.

  The double-sided pressure-sensitive adhesive tape of the present invention is preferably formed in a roll shape or a sheet shape with a separator provided on at least one side. As the separator, a publicly-known and publicly-used material that has been peel-treated on at least one surface of paper or plastic film can be used. In order to form a double-sided pressure-sensitive adhesive tape, a method is used in which a pressure-sensitive adhesive is applied to the separator with a roll coater or a die coater, dried with a drier to form a pressure-sensitive adhesive layer, and then transferred to a polyethylene foam. The preferable thickness of the pressure-sensitive adhesive layer after drying is 30 to 200 μm, more preferably 40 to 100 μm.

  The double-sided pressure-sensitive adhesive tape of the present invention has a temperature of 23 ° C. and a relative humidity of 50%, and is bonded to a polypropylene plate with a 2 kg roller at a pressure bonding speed of 5 mm / s and a pressure of 1 reciprocation at 23 ° C. The 90 ° adhesive strength is preferably 30 N / 20 mm or more, and more preferably 35 N / 20 mm or more. The 90 ° adhesive strength at 90 ° C. is preferably 10 N / 20 mm or more, more preferably 20 N / 20 mm or more, and the 90 ° adhesive strength at −40 ° C. is preferably 20 N / mm, more preferably 30 N / It is 20 mm or more.

  Detailed adhesive force measurement conditions are as follows. A polycarbonate plate having a thickness of 0.5 mm is laminated on one side of the double-sided pressure-sensitive adhesive sheet and cut into a width of 20 mm. A polypropylene plate is coated with K500 manufactured by 3M as a primer, left to stand at 23 ° C. and 50% RH for 10 minutes, and dried to obtain an adherend. The double-sided pressure-sensitive adhesive sheet was pressure-bonded to the adherend by applying 2 kg roller 1 reciprocating pressure. After standing at 23 ° C. and 50% RH for 24 hours, after leaving the sample in an atmosphere of 90 ° C., 23 ° C. and 50% RH and −40 ° C. for 1 hour, double-sided tape at a speed of 300 mm / min in the 90 ° direction under the same atmosphere The adhesive strength when the film was peeled from the adherend was measured.

  Further, the 90 ° C. holding force under the following measurement conditions is preferably 15 hours or more, and more preferably 24 hours or more.

  The detailed measurement conditions of 90 ° C. holding force are as follows. After laminating a soft aluminum foil having a thickness of 50 μm on one side of the double-sided pressure-sensitive adhesive sheet, it is cut into a width of 20 mm × 70 mm. It stuck on the stainless steel plate so that the pasting area might be 20 mm × 20 mm, and it was pressure-bonded by applying a reciprocating pressure with a 2 kg roller. After leaving at 23 ° C. and 50% RH for 1 hour, a load of 500 g was applied in the shear direction in a dryer at 90 ° C., and the drop time was measured. When it did not fall for 24 hours, it was recorded as 24 hours or more and the test was terminated.

Example 1
[Preparation of adhesive solution a]
(1) 74.7 parts by mass of butyl acrylate (hereinafter “parts”), 18.7 parts of 2-ethylhexyl acrylate, and vinyl acetate in a reaction vessel equipped with a stirrer, a cold flow cooler, a thermometer, a dropping funnel and a nitrogen gas inlet. 5 parts, 2.0 parts of acrylic acid, 0.1 parts of β-hydroxyethyl acrylate, 100 parts by weight of monomer and 0.2 part of 2,2′-azobisisobutylnitrile as a polymerization initiator are dissolved in 100 parts of ethyl acetate. Then, polymerization was carried out at 80 ° C. for 8 hours to obtain an acrylic copolymer solution having a weight average molecular weight of 700,000.
(2) 10 parts of polymerized rosin ester-based resin (D-160 manufactured by Arakawa Chemical Co., Ltd.) and 10 parts of disproportionated rosin ester (A-100 manufactured by Arakawa Chemical Co., Ltd.) per 100 parts of the acrylic copolymer solid content. A pressure-sensitive adhesive solution a having a solid content of 40% was obtained.

[Preparation of double-sided PSA sheet]
1.0 part of an isocyanate-based crosslinking agent (Dai Nippon Ink Chemical Co., Ltd. Burnock NC-40, solid content 40%) was added to 100 parts by mass of the solid content of the pressure-sensitive adhesive solution a. The pressure-sensitive adhesive solution obtained by coating the obtained pressure-sensitive adhesive solution on a 75 μm-thick polyester film having been subjected to a release treatment so that the thickness after drying becomes 75 μm and drying at 100 ° C. for 2 minutes. The agent layer was corona on both sides of a polyethylene foam (Borara H05002 manufactured by Sekisui Chemical Co., Ltd.) having a thickness of 0.2 mm, an apparent density of 0.2 g / cc, and an area shrinkage of 11% after being left for 22 hours in an atmosphere at 90 ° C. After the discharge treatment, it was transferred and laminated at a pressure of 4 kgf / cm to obtain a double-sided PSA sheet. The obtained double-sided PSA sheet was used for the test after aging in an oven at 40 ° C. for 2 days. The gel fraction of the pressure-sensitive adhesive layer of the double-sided PSA sheet was 35%, the loss tangent peak temperature was -7 ° C, and the loss tangent at 90 ° C was 0.5.

(Example 2)
[Adjustment of adhesive solution b]
The adhesive solution a described in Example 1 except that 14 parts of polymerized rosin ester resin (D-160 manufactured by Arakawa Chemical Co., Ltd.) and 6 parts of disproportionated rosin ester (A-100 manufactured by Arakawa Chemical Co., Ltd.) were used. A pressure-sensitive adhesive solution b was obtained in the same manner.

[Preparation of double-sided PSA sheet]
A double-sided PSA sheet was obtained in the same manner as in Example 1 except that the PSA solution b was used. The gel fraction of the pressure-sensitive adhesive layer of the double-sided PSA sheet was 35%, the loss tangent peak temperature was -7 ° C, and the loss tangent at 90 ° C was 0.5.

(Comparative Example 1)
[Adjustment of adhesive solution c]
The adhesive solution a described in Example 1 except that 20 parts of polymerized rosin ester resin (D-160 manufactured by Arakawa Chemical Co., Ltd.) and 10 parts of disproportionated rosin ester (A-100 manufactured by Arakawa Chemical Co., Ltd.) were used. A pressure-sensitive adhesive solution c was obtained in the same manner.

[Preparation of double-sided PSA sheet]
A double-sided PSA sheet was obtained in the same manner as in Example 1 except that the PSA solution b was used. The gel fraction of the pressure-sensitive adhesive layer of the double-sided PSA sheet was 35%, the peak temperature of loss tangent was −5 ° C., and the loss tangent at 90 ° C. was 0.65.

(Comparative Example 2)
Other than using a polyethylene foam (5S002 manufactured by Toray Pef Processing Co., Ltd.) having a thickness of 0.2 mm, an apparent density of 0.2 g / cc, and an area shrinkage of 26% after standing for 22 hours in an atmosphere at 90 ° C. Obtained the double-sided adhesive sheet by the same method as Example 1.

(Comparative Example 3)
GT-7104 manufactured by 3M Company was used as an acrylic foam substrate double-sided PSA sheet.

  The following evaluation was performed about said polyethylene foam and a double-sided adhesive sheet. The obtained results are shown in Table 1.

[Foamed area shrinkage]
A polyethylene foam cut into 15 cm × 15 cm is drawn vertically and horizontally in the center and at a location 50 mm away from the center, and three lines in parallel both vertically and horizontally. The length of the 10 cm length inside the sample where the vertical and horizontal lines intersect is measured on each of the three vertical and horizontal sides. The average value of the three measured values in the vertical and horizontal directions is obtained. The area is obtained by the product of the obtained vertical and horizontal average lengths. The area is determined in the same manner after being left in a dryer at 90 ° C. for 22 hours. The area after leaving at 90 ° C. is divided by the area before leaving at 90 ° C. to determine the rate of change.

[Cut strength]
A sample cut at a width of 10 mm was placed on a tensile tester so that the distance between marked lines was 40 mm, and the cutting strength and the elongation at the time of cutting were measured at 90 ° C. at a speed of 500 mm / min.

[25% compressive strength]
The samples cut into 50 mm squares are overlaid until the thickness is 25 mm. The sample is sandwiched between plates having a larger area than the sample, and the strength is measured when the sample is compressed at a rate of 10 mm / min at 23 ° C. and compressed by 25% in the thickness direction.

[Retention force]
After laminating a soft aluminum foil having a thickness of 50 μm on one side of the double-sided pressure-sensitive adhesive sheet, it is cut into a width of 20 mm × 70 mm. It stuck on the stainless steel plate so that the pasting area might be 20 mm × 20 mm, and it was pressure-bonded by applying a reciprocating pressure with a 2 kg roller. After leaving at 23 ° C. and 50% RH for 1 hour, a load of 500 g was applied in the shear direction in drying at 90 ° C., and the dropping time was measured. When it did not fall for 24 hours, it was recorded as 24 hours or more and the test was terminated.

[Adhesive strength]
A polycarbonate plate having a thickness of 0.5 mm is laminated on one side of the double-sided pressure-sensitive adhesive sheet and cut into a width of 20 mm. A polypropylene plate is coated with K500 manufactured by 3M as a primer, left to stand at 23 ° C. and 50% RH for 10 minutes, and dried to obtain an adherend. The double-sided pressure-sensitive adhesive sheet was pressure-bonded to the adherend by applying 2 kg roller 1 reciprocating pressure. After standing at 23 ° C. and 50% RH for 24 hours, after leaving the sample in an atmosphere of 90 ° C., 23 ° C. and 50% RH and −40 ° C. for 1 hour, double-sided tape at a speed of 300 mm / min in the 90 ° direction under the same atmosphere The adhesive strength when the film was peeled from the adherend was measured.

  As is clear from the above Examples and Comparative Examples, the double-sided pressure-sensitive adhesive tape of the present invention has excellent adhesive strength and holding power under both high temperature and low temperature environments.

Claims (5)

A double-sided pressure-sensitive adhesive tape having a pressure-sensitive adhesive layer made of an acrylic pressure-sensitive adhesive containing an acrylic copolymer and a tackifying resin, and a base material made of polyethylene foam,
The content of the tackifying resin in the acrylic pressure-sensitive adhesive is 10 to 25 parts by mass with respect to 100 parts by mass of the acrylic copolymer,
The tackifying resin contains a rosin resin (a) having a softening point of 80 ° C. or more and less than 120 ° C. and a rosin resin (b) having a softening point of 120 ° C. or more and 200 ° C. or less, and the mass ratio (a ) / (B) is 1/3 to 3/1,
The double-sided pressure-sensitive adhesive tape, wherein the base material is a base material having a heat shrinkage area ratio of 15% or less before and after standing at a temperature of 90 ° C. for 22 hours. The double-sided pressure-sensitive adhesive tape according to claim 1, wherein the apparent density of the substrate is 0.06 to 0.31 g / cc. The double-sided pressure-sensitive adhesive tape according to claim 1 or 2, wherein the base material has a cutting strength at 90 ° C of 0.5 MPa or more and a 25% compressive strength at 23 ° C of 0.2 MPa or less. The double-sided pressure-sensitive adhesive tape according to any one of claims 1 to 3, wherein a drop time in a holding force test at 90 ° C is 24 hours or more. In an environment of a temperature of 23 ° C. and a relative humidity of 50%, the polypropylene plate is crimped with a 2 kg roller, with a crimping speed of 5 mm / s and a single crimping cycle.
Using a stainless steel plate for the adherend, the 90 ° peel adhesion at a peeling speed of 300 mm / min in an atmosphere at 90 ° C. is 20 to 40 N / 20 mm width,
The double-sided pressure-sensitive adhesive tape according to any one of claims 1 to 4, wherein a polypropylene plate is used as the adherend and the 90 ° peel-off adhesive strength is 30 to 50 N / mm at a peeling speed of 300 mm / min in an atmosphere of -40 ° C.