阅读说明：本技术 压敏粘接带 (Pressure-sensitive adhesive tape ) 是由 泽村周 山本修平 于 2021-06-02 设计创作，主要内容包括：双面压敏粘接带(1)具备无纺布基材(2)和在无纺布基材(2)的厚度方向的一侧配置的第1压敏粘接剂层(3)。使无纺布基材(2)中含有着色剂、使第1压敏粘接剂层(3)中不含有着色剂。进而,将无纺布基材(2)的单位面积重量调整为10g/m～(2)以上且30g/m～(2)以下、并且将无纺布基材(2)的厚度调整为20μm以上且50μm以下。(The double-sided pressure-sensitive adhesive tape (1) comprises a nonwoven fabric base material (2) and a 1 st pressure-sensitive adhesive layer (3) arranged on one side of the nonwoven fabric base material (2) in the thickness direction. The nonwoven fabric base material (2) contains a colorant, and the 1 st pressure-sensitive adhesive layer (3) does not contain a colorant. Further, the basis weight of the nonwoven fabric base material (2) was adjusted to 10g/m 2 Above and 30g/m 2 The thickness of the nonwoven fabric base material (2) is adjusted to 20 μm or more and 50 μm or less.)

1. A pressure-sensitive adhesive tape is characterized by comprising:

a nonwoven fabric base material, and

a pressure-sensitive adhesive layer disposed on one side of the nonwoven fabric substrate in the thickness direction,

the non-woven fabric base material comprises a coloring agent,

the weight per unit area of the non-woven fabric base material is 10g/m²Above and 30g/m²In the following, the following description is given,

the thickness of the nonwoven fabric substrate is 20-50 μm,

the pressure-sensitive adhesive layer does not contain a colorant.

2. The pressure-sensitive adhesive tape according to claim 1, wherein the pressure-sensitive adhesive layer contains a water-dispersed pressure-sensitive adhesive composition.

3. The pressure-sensitive adhesive tape according to claim 1 or 2, which is used for fixing a wiring harness.

Technical Field

The present invention relates to a pressure-sensitive adhesive tape.

Background

Pressure-sensitive adhesive tapes are used in various industrial fields to fix an object to an adherend. For example, in the manufacture of various industrial products such as automobiles, a plurality of objects are adhered to an adherend by a plurality of pressure-sensitive adhesive tapes. However, when the pressure-sensitive adhesive tape is left behind, the object may fall off from the adherend, and the reliability of the product may be lowered. Therefore, it is desired to improve the visual recognition of the pressure-sensitive adhesive tape.

As such a pressure-sensitive adhesive tape, for example, there has been proposed a pressure-sensitive adhesive sheet including a nonwoven fabric and a pressure-sensitive adhesive layer disposed on the nonwoven fabric, the pressure-sensitive adhesive layer containing a colorant (see, for example, patent document 1).

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2015-40218

Disclosure of Invention

Problems to be solved by the invention

However, when an object is adhered to an adherend, the pressure-sensitive adhesive tape may adhere to a curved surface of the adherend. However, if the pressure-sensitive adhesive sheet described in patent document 1 is adhered to a curved surface, the pressure-sensitive adhesive sheet may be peeled off from the curved surface of an adherend due to the elasticity of the nonwoven fabric.

The invention provides a pressure-sensitive adhesive tape which can improve visual recognizability and can inhibit stripping from an adherend.

Means for solving the problems

The invention [1]Comprises a pressure-sensitive adhesive tape comprising a nonwoven fabric base material and a pressure-sensitive adhesive layer disposed on one side of the nonwoven fabric base material in the thickness direction, wherein the nonwoven fabric base material contains a colorant, and the basis weight of the nonwoven fabric base material is 10g/m²Above and 30g/m²The nonwoven fabric base material has a thickness of 20 to 50 μm, and the pressure-sensitive adhesive layer does not contain a colorant.

The invention [2] comprises the pressure-sensitive adhesive tape according to [1], wherein the pressure-sensitive adhesive layer contains a water-dispersed pressure-sensitive adhesive composition.

The invention [3] comprises the pressure-sensitive adhesive tape according to the above [1] or [2], which is used for fixing a wire harness.

ADVANTAGEOUS EFFECTS OF INVENTION

In the pressure-sensitive adhesive tape of the present invention, the pressure-sensitive adhesive layer does not contain a colorant, and the nonwoven fabric base material contains a colorant. Further, since the basis weight of the nonwoven fabric base material is not less than the lower limit and the thickness of the nonwoven fabric base material is not less than the lower limit, the visibility of the pressure-sensitive adhesive tape can be improved. Further, since the basis weight of the nonwoven fabric base material is not more than the upper limit and the thickness of the nonwoven fabric base material is not more than the upper limit, the elastic force of the nonwoven fabric base material can be reduced, and the pressure-sensitive adhesive tape can be inhibited from peeling from the adherend.

Drawings

Fig. 1 shows a schematic configuration of a double-sided pressure-sensitive adhesive tape as one embodiment of the pressure-sensitive adhesive tape of the present invention.

Description of the reference numerals

1 double-sided pressure-sensitive adhesive tape

2 non-woven fabric base material

3 st pressure-sensitive adhesive layer

4 nd 2 nd pressure-sensitive adhesive layer

5 st Release liner

6 nd 2 nd release liner

Detailed Description

1. Double-sided pressure-sensitive adhesive tape

A double-sided pressure-sensitive adhesive tape 1 as one embodiment of the pressure-sensitive adhesive tape of the present invention will be described with reference to fig. 1.

The double-sided pressure-sensitive adhesive tape 1 includes: a nonwoven fabric substrate 2, a 1 st pressure-sensitive adhesive layer 3, a 2 nd pressure-sensitive adhesive layer 4, a 1 st release liner 5, and a 2 nd release liner 6.

The nonwoven fabric base material 2 is formed by winding fibers instead of weaving. Examples of the fibers of the nonwoven fabric substrate 2 include natural fibers (e.g., plant fibers such as wood pulp, manila hemp, and cotton, and animal fibers such as wool and silk), synthetic fibers (e.g., cellulose fibers such as acetate fibers and rayon fibers, polyester fibers, polyamide fibers, and polyvinyl alcohol fibers (vinylon fibers)), and inorganic fibers (e.g., glass fibers and carbon fibers). The fibers may be used singly or in combination of 2 or more.

The fibers preferably include natural fibers and/or synthetic fibers, more preferably include at least one selected from the group consisting of plant fibers, polyvinyl alcohol fibers, and cellulose fibers, and further preferably include at least one selected from the group consisting of wood pulp, rayon fibers, and polyvinyl alcohol fibers.

The nonwoven fabric substrate 2 contains a colorant. In other words, the nonwoven fabric substrate 2 contains fibers and a colorant.

Examples of the colorant include inorganic pigments (e.g., black pigments such as carbon black, red pigments such as red lead and iron oxide red, yellow pigments such as chrome yellow and zinc yellow, blue pigments such as ultramarine blue, prussian blue and YInMn blue, white pigments such as zinc white, lead white, lithopone, titanium dioxide and barite powder), organic pigments, polycyclic pigments, azo pigments, lake pigments, fluorescent pigments, direct dyes (e.g., black dyes, red dyes, yellow dyes and blue dyes), reactive dyes, sulfur dyes, basic dyes, acid dyes, gold-containing acid dyes, indigo dyes, vat dyes, disperse dyes and cationic dyes. Examples of the direct dye include azo dyes and anthraquinone dyes. The coloring agent may be used singly or in combination of 2 or more.

The colorant is appropriately selected depending on the color of the adherend. The colorant preferably has a different color from the adherend. For example, when the adherend is a ceiling material of a vehicle and has a light color such as white, the colorant preferably has black.

The colorant preferably contains an inorganic pigment, more preferably contains a black pigment, and further preferably contains carbon black. The colorant is preferably formed of an inorganic pigment.

When the colorant contains an inorganic pigment, the colorant can be inhibited from moving from the nonwoven fabric base material 2 to the 1 st pressure-sensitive adhesive layer 3 and/or the 2 nd pressure-sensitive adhesive layer 4, and the colorant can be inhibited from contaminating manufacturing equipment (e.g., a roller or the like) of the double-sided pressure-sensitive adhesive tape 1.

The content of the colorant is, for example, 0.05 parts by mass or more, preferably 0.5 parts by mass or more, and is, for example, 2.0 parts by mass or less, preferably 1.5 parts by mass or less, per 100 parts by mass of the fibers (the nonwoven fabric substrate before the colorant is added).

When the content ratio of the colorant is not less than the lower limit, the visibility of the double-sided pressure-sensitive adhesive tape 1 can be reliably improved.

The nonwoven fabric base material 2 had a basis weight of 10g/m²Above, preferably 14g/m²Above and 30g/m²Below, preferably 20g/m²The following.

When the basis weight of the nonwoven fabric base material 2 is not less than the lower limit, the visibility of the double-sided pressure-sensitive adhesive tape 1 can be improved. When the basis weight of the nonwoven fabric base material 2 is not more than the upper limit, the elastic force of the nonwoven fabric base material 2 can be reduced, and the adhesiveness of the double-sided pressure-sensitive adhesive tape 1 to a curved surface can be improved. Therefore, the double-sided pressure-sensitive adhesive tape 1 can be inhibited from peeling from the curved surface.

The thickness of the nonwoven fabric substrate 2 is 20 μm or more, preferably 25 μm or more, more preferably 32 μm or more, and 50 μm or less, preferably 45 μm or less.

When the thickness of the nonwoven fabric base material 2 is not less than the lower limit, the visibility of the double-sided pressure-sensitive adhesive tape 1 can be reliably improved. When the thickness of the nonwoven fabric base material 2 is equal to or less than the upper limit, the elastic force of the nonwoven fabric base material 2 can be reliably reduced, and the adhesiveness of the double-sided pressure-sensitive adhesive tape 1 to a curved surface can be reliably improved. Therefore, the peeling of the double-sided pressure-sensitive adhesive tape 1 from the curved surface can be stably suppressed.

The air permeability of the nonwoven fabric substrate 2 is, for example, 0.10s or more, preferably 0.15s or more, and is, for example, 1.00s or less, preferably 0.80s or less, more preferably 0.50s or less. The time for which air having an air permeability of 100cc passes through a sample in which 4 nonwoven fabric substrates are laminated may be determined in accordance with JIS P8177: 2009 (same applies hereinafter).

The total light transmittance of the nonwoven fabric substrate 2 is, for example, 5% or more and 30% or less. The total light transmittance can be measured according to the method described in JIS K7136 (the same applies hereinafter).

In the production of such a nonwoven fabric substrate 2, for example, a nonwoven fabric substrate not containing a colorant is immersed in a colorant-containing liquid containing a colorant, and then dried. Alternatively, the nonwoven fabric substrate 2 may be formed of fibers colored with a colorant.

The 1 st pressure-sensitive adhesive layer 3 is disposed on one side in the thickness direction of the nonwoven fabric base material 2. Specifically, the 1 st pressure-sensitive adhesive layer 3 is disposed on one surface of the nonwoven fabric base material 2 in the thickness direction. The 1 st pressure-sensitive adhesive layer 3 has a flat plate shape (sheet shape). The thickness of the 1 st pressure-sensitive adhesive layer 3 is, for example, 40 μm or more and 80 μm or less.

The 1 st pressure-sensitive adhesive layer 3 does not contain the above colorant. Therefore, the pressure-sensitive adhesive force of the 1 st pressure-sensitive adhesive layer 3 can be improved as compared with the case where the 1 st pressure-sensitive adhesive layer 3 contains a colorant.

The 1 st pressure-sensitive adhesive layer 3 contains a pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition is not particularly limited as long as it does not contain a colorant. As the pressure-sensitive adhesive composition, a water-dispersible pressure-sensitive adhesive composition can be preferably cited from the viewpoint of environmental load. In other words, the 1 st pressure-sensitive adhesive layer 3 contains, preferably is formed of, an aqueous dispersion type pressure-sensitive adhesive composition.

Examples of the water-dispersible pressure-sensitive adhesive composition include the water-dispersible pressure-sensitive adhesive composition described in japanese patent application laid-open publication No. 2011-16943.

The water-dispersed pressure-sensitive adhesive composition contains at least a (meth) acrylic polymer. It is noted that (meth) acrylic acid is synonymous with methacrylic acid and/or acrylic acid.

The (meth) acrylic polymer is prepared, for example, by adding an emulsion containing a (meth) acrylic monomer, an emulsifier and water to an initiator solution (described later) containing a polymerization initiator and emulsion-polymerizing the (meth) acrylic monomer.

The (meth) acrylic monomer contains an alkyl (meth) acrylate as a main component.

Examples of the alkyl (meth) acrylate include alkyl (meth) acrylates having an alkyl group having 1 to 3 carbon atoms (e.g., methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, etc.), and alkyl (meth) acrylates having an alkyl group having 4 to 12 carbon atoms (e.g., butyl (meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, pentyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, etc.).

The alkyl (meth) acrylate may be used singly or in combination of 2 or more.

The alkyl (meth) acrylate includes at least an alkyl (meth) acrylate having an alkyl group with 4 to 12 carbon atoms, and preferably includes an alkyl (meth) acrylate having an alkyl group with 4 to 12 carbon atoms and an alkyl (meth) acrylate having an alkyl group with 1 to 3 carbon atoms.

The content ratio of the alkyl (meth) acrylate having an alkyl group having 4 to 12 carbon atoms is, for example, 60 mass% or more, preferably 80 mass% or more, and for example, 100 mass% or less, preferably 90 mass% or less, with respect to 100 mass% of the (meth) acrylic monomer.

The content ratio of the alkyl (meth) acrylate having an alkyl group with 1 to 3 carbon atoms is, for example, 0 mass% or more, preferably 5 mass% or more, and for example, 35 mass% or less, preferably 15 mass% or less, relative to 100 mass% of the (meth) acrylic monomer.

The content ratio of the alkyl (meth) acrylate is, for example, 60 mass% or more, preferably 85 mass% or more, and is, for example, 100 mass% or less, preferably 98 mass% or less, with respect to 100 mass% of the (meth) acrylic monomer.

The (meth) acrylic monomer preferably further contains (meth) acrylic acid and a (meth) acryloyl group-containing alkoxysilane compound.

The content ratio of (meth) acrylic acid is, for example, 0 mass% or more, preferably 1 mass% or more, and is, for example, 5 mass% or less, preferably 3 mass% or less, with respect to 100 mass% of the (meth) acrylic monomer.

The (meth) acryloyl group-containing alkoxysilane compound contains a (meth) acryloyl group and an alkoxysilyl group.

Examples of the (meth) acryloyl group-containing alkoxysilane compound include 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 3- (meth) acryloyloxypropylmethyldimethoxysilane, and 3- (meth) acryloyloxypropylmethyldiethoxysilane.

The (meth) acryloyl group-containing alkoxysilane compound may be used alone or in combination of 2 or more.

The (meth) acryloyl group-containing alkoxysilane compound preferably contains 3- (meth) acryloyloxypropyltriethoxysilane, and more preferably is formed from 3- (meth) acryloyloxypropyltriethoxysilane.

The content ratio of the (meth) acryloyl group-containing alkoxysilane compound is, for example, 0 mass% or more, preferably 0.001 mass% or more, and, for example, 0.1 mass% or less, preferably 0.05 mass% or less, relative to 100 mass% of the (meth) acrylic monomer.

The content of the (meth) acrylic monomer in the emulsion is, for example, 60 mass% or more, preferably 70 mass% or more, and is, for example, 90 mass% or less, preferably 80 mass% or less.

Examples of the emulsifier include anionic emulsifiers (for example, sodium lauryl sulfate, ammonium lauryl sulfate, sodium dodecylbenzenesulfonate, sodium polyoxyethylene alkyl ether sulfate, ammonium polyoxyethylene alkylphenyl ether sulfate, sodium polyoxyethylene alkylphenyl ether sulfate and the like), nonionic emulsifiers (for example, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether and the like), and the like.

As the emulsifier, a radical polymerizable emulsifier obtained by introducing a radical polymerizable group (for example, an acryl group or the like) into the anionic emulsifier or the nonionic emulsifier may be used.

The emulsifiers may be used alone or in combination of 2 or more.

The emulsifier preferably comprises an anionic emulsifier, preferably sodium polyoxyethylene alkyl ether sulphate. The emulsifier is preferably formed from an anionic emulsifier.

The content of the emulsifier in the emulsion is, for example, 0.01% by mass or more, preferably 0.5% by mass or more, and is, for example, 5.0% by mass or less, preferably 3.0% by mass or less.

The content of the emulsifier is, for example, 0.5 parts by mass or more, preferably 1.0 parts by mass or more, and is, for example, 5.0 parts by mass or less, preferably 3.0 parts by mass or less, relative to 100 parts by mass of the (meth) acrylic monomer.

The content of water in the emulsion is, for example, 5 mass% or more, preferably 10 mass% or more, and is, for example, 35 mass% or less, preferably 25 mass% or less.

The content of water is, for example, 10 parts by mass or more, preferably 20 parts by mass or more, and is, for example, 50 parts by mass or less, preferably 40 parts by mass or less, relative to 100 parts by mass of the (meth) acrylic monomer.

Further, the emulsion preferably further contains a chain transfer agent.

Examples of the chain transfer agent include mercaptans such as dodecanethiol (dodecyl mercaptan), glycidyl mercaptan, and 2-mercaptoethanol.

The chain transfer agent may be used alone or in combination of 2 or more.

The chain transfer agent preferably comprises, more preferably is formed from, dodecyl mercaptan.

The content of the chain transfer agent in the emulsion is, for example, 0 mass% or more and 0.5 mass% or less.

The content ratio of the chain transfer agent is, for example, 0 part by mass or more, preferably 0.01 part by mass or more, and is, for example, 0.5 part by mass or less, preferably 0.05 part by mass or less, relative to 100 parts by mass of the (meth) acrylic monomer.

Examples of the polymerization initiator include azo initiators, peroxide initiators, and redox initiators comprising a combination of a peroxide and a reducing agent.

Examples of the azo initiator include 2,2 ' -azobis [ N- (2-carboxyethyl) -2-methylpropionamidine ] hydrate, 2 ' -azobisisobutyronitrile, 2 ' -azobis (2-methylpropionamidine) disulfate, 2 ' -azobis (2-amidinopropane) dihydrochloride, 2 ' -azobis [2- (5-methyl-2-imidazolin-2-yl) propane ] dihydrochloride, and 2,2 ' -azobis (N, N ' -dimethyleneisobutylamidine) dihydrochloride.

Examples of the peroxide initiator include peroxosulfates (e.g., potassium persulfate, ammonium persulfate, etc.), benzoyl peroxide, t-butyl hydroperoxide, and hydrogen peroxide.

Examples of the redox initiator include a combination of peroxosulfate and sodium hydrogen sulfite, and a combination of hydrogen peroxide and sodium ascorbate.

The polymerization initiators may be used alone or in combination of 2 or more.

The polymerization initiator is preferably a combination of an azo initiator and a redox initiator.

When an azo initiator and a redox initiator are used in combination, the emulsion is first added to an initiator solution containing an azo initiator to emulsion-polymerize a (meth) acrylic monomer.

The mixing ratio of the azo initiator is, for example, 0.01 parts by mass or more, preferably 0.05 parts by mass or more, and is, for example, 0.5 parts by mass or less, preferably 0.2 parts by mass or less, relative to 100 parts by mass of the (meth) acrylic monomer.

The polymerization temperature in the presence of the azo initiator is, for example, 20 ℃ or more, preferably 40 ℃ or more, and is, for example, 100 ℃ or less, preferably 80 ℃ or less.

Then, a peroxide of a redox initiator is added to the reaction liquid of the emulsion polymerization. The mixing ratio of the peroxide is, for example, 0.03 parts by mass or more, preferably 0.05 parts by mass or more, and is, for example, 0.2 parts by mass or less, preferably 0.1 parts by mass or less, relative to 100 parts by mass of the (meth) acrylic monomer.

Then, a reducing agent of a redox initiator is added to the reaction solution to which the peroxide is added, and a redox treatment is performed. The mixing ratio of the reducing agent is, for example, 0.1 part by mass or more, preferably 0.2 part by mass or more, and is, for example, 1.0 part by mass or less, preferably 0.8 part by mass or less, relative to 100 parts by mass of the (meth) acrylic monomer.

The temperature range of the redox treatment is, for example, the same as the polymerization temperature range in the presence of an azo initiator.

Thereby, a (meth) acrylic polymer as a polymer of a (meth) acrylic monomer is produced, and a (meth) acrylic polymer emulsion containing the (meth) acrylic polymer and water is prepared.

Further, the 1 st pressure-sensitive adhesive layer 3 containing the pressure-sensitive adhesive composition was prepared from the (meth) acrylic polymer emulsion.

The acrylic polymer emulsion may be cooled to room temperature (25 ℃ C.) as required. Further, a pH adjuster (e.g., ammonia water) may be added to the acrylic polymer emulsion as needed. Thereby, the pH of the acrylic polymer emulsion is adjusted to, for example, 5.0 or more and 8.0 or less.

The acrylic polymer emulsion has a solid content concentration (NV) of, for example, 30 mass% or more, preferably 40 mass% or more, and, for example, 70 mass% or less, preferably 60 mass% or less.

The average particle diameter of the emulsion in the acrylic polymer emulsion is, for example, 100nm or more and 300nm or less.

Then, the (meth) acrylic polymer emulsion is applied to, for example, the nonwoven fabric substrate 2 or the 1 st release liner 5, and then dried as necessary.

In the above manner, the 1 st pressure-sensitive adhesive layer 3 containing the water dispersion type pressure-sensitive adhesive composition was prepared.

The aqueous dispersion pressure-sensitive adhesive composition preferably contains a tackifier in addition to the (meth) acrylic polymer. In this case, a tackifier is added to the (meth) acrylic polymer emulsion.

Examples of the tackifier include rosin resins, rosin derivative resins, petroleum resins, terpene resins, phenol resins, and ketone resins.

The tackifier may be used alone or in combination of 2 or more.

Among the tackifiers, rosin-based resins are preferably used.

The content of the tackifier is, for example, 5 parts by mass or more, preferably 10 parts by mass or more, and is, for example, 40 parts by mass or less, preferably 30 parts by mass or less, relative to 100 parts by mass of the (meth) acrylic polymer.

The aqueous dispersion type pressure-sensitive adhesive composition may contain known additives such as a viscosity modifier, a leveling agent, a plasticizer, a filler, a stabilizer, an antiseptic agent, and an antioxidant in an appropriate ratio as required.

The 2 nd pressure-sensitive adhesive layer 4 is disposed on the other side in the thickness direction of the nonwoven fabric base material 2. Specifically, the 2 nd pressure-sensitive adhesive layer 4 is disposed on the other surface in the thickness direction of the nonwoven fabric base material 2. The description of the 2 nd pressure-sensitive adhesive layer 4 is the same as that of the 1 st pressure-sensitive adhesive layer 3. Therefore, the description of the 2 nd pressure-sensitive adhesive layer 4 is omitted.

The 1 st release liner 5 is located on the opposite side of the nonwoven fabric base material 2 from the 1 st pressure-sensitive adhesive layer 3. The 1 st release liner 5 is releasably adhered to one surface in the thickness direction of the 1 st pressure-sensitive adhesive layer 3 in order to protect the 1 st pressure-sensitive adhesive layer 3 before use of the double-sided pressure-sensitive adhesive tape 1. The 1 st release liner 5 has a flat plate shape (sheet shape). The 1 st release liner 5 is formed of a flexible resin film. Examples of the resin film include a fluorine-based film such as polytetrafluoroethylene, a polyolefin film such as polyethylene or polypropylene, and a polyester film such as polyethylene terephthalate.

The bonding surface of the 1 st release liner 5 is subjected to surface treatment with a release treatment agent as needed. Examples of the release treatment agent include silicone release treatment agents, long-chain alkyl release treatment agents, fluorine release treatment agents, molybdenum sulfide release treatment agents, and the like. The release treatment agent may be used alone or in combination of 2 or more.

The 1 st release liner 5 is peeled from the 1 st pressure-sensitive adhesive layer 3 at the time of use of the double-sided pressure-sensitive adhesive tape 1. Then, the exposed 1 st pressure-sensitive adhesive layer 3 is pressure-sensitive bonded to an adherend or object.

The 2 nd release liner 6 is located on the opposite side of the nonwoven fabric base material 2 from the 2 nd pressure-sensitive adhesive layer 4. The 2 nd pressure-sensitive adhesive layer 4 is releasably adhered to the other surface in the thickness direction of the 2 nd pressure-sensitive adhesive layer 4 in order to protect the 2 nd pressure-sensitive adhesive layer 4 before use of the double-sided pressure-sensitive adhesive tape 1. The description of the 2 nd release liner 6 is the same as the 1 st release liner 5. Therefore, the description of the 2 nd release liner 6 is omitted. The 2 nd release liner 6 is peeled from the 2 nd pressure-sensitive adhesive layer 4 at the time of use of the double-sided pressure-sensitive adhesive tape 1. Then, the exposed 2 nd pressure-sensitive adhesive layer 4 is pressure-sensitive bonded to an adherend or an object.

In the production of such a double-sided pressure-sensitive adhesive tape 1, for example, the (meth) acrylic polymer emulsion is applied to the 1 st release liner 5 by a known coating method. Thereafter, the coating film of the (meth) acrylic polymer emulsion is dried as necessary, thereby forming the 1 st pressure-sensitive adhesive layer 3.

Next, the 1 st pressure-sensitive adhesive layer 3 on the 1 st release liner 5 is pressure-bonded to the one surface in the thickness direction of the nonwoven fabric substrate 2 so that the 1 st pressure-sensitive adhesive layer 3 is in direct contact with the one surface in the thickness direction of the nonwoven fabric substrate 2.

Then, the (meth) acrylic polymer emulsion is directly applied to the other surface of the nonwoven fabric substrate 2 in the thickness direction by a known application method. Thereafter, the coating film is dried as necessary to form the 2 nd pressure-sensitive adhesive layer 4.

Then, the 2 nd release liner 6 is pressure-bonded to the 2 nd pressure-sensitive adhesive layer 4 on the opposite side of the nonwoven fabric base material 2.

In the above operation, the double-sided adhesive tape 1 is manufactured.

The double-sided adhesive tape 1 includes a 2 nd release liner 6, a 2 nd pressure-sensitive adhesive layer 4, a nonwoven fabric base material 2, a 1 st pressure-sensitive adhesive layer 3, and a 1 st release liner 5 in this order in the thickness direction of the nonwoven fabric base material 2.

Such a double-sided pressure-sensitive adhesive tape 1 is used for manufacturing various industrial products, for example, and is preferably used for manufacturing automobiles. More specifically, the double-sided pressure-sensitive adhesive tape 1 is suitably used when an automobile component (e.g., a wire harness) is fixed to a vehicle body frame having a curved surface. In other words, the double-sided adhesive tape 1 is used for fixing automobile parts (wire harnesses).

When the double-sided pressure-sensitive adhesive tape 1 is used, as described above, the 1 st release liner 5 is peeled from the 1 st pressure-sensitive adhesive layer 3, and the 2 nd release liner 6 is peeled from the 2 nd pressure-sensitive adhesive layer 4. Therefore, in the use state of the double-sided adhesive tape 1, the tape main body 1A including the nonwoven fabric base material 2, the 1 st pressure-sensitive adhesive layer 3, and the 2 nd pressure-sensitive adhesive layer 4 and not including the 1 st release liner 5 and the 2 nd release liner 6 is bonded to the adherend.

In the double-sided pressure-sensitive adhesive tape 1, the 1 st pressure-sensitive adhesive layer 3 and the 2 nd pressure-sensitive adhesive layer 4 do not contain a colorant, and the nonwoven fabric base material 2 contains a colorant. The weight per unit area of the nonwoven fabric base material 2 is not less than the lower limit, and the thickness of the nonwoven fabric base material 2 is not less than the lower limit. Therefore, the double-sided adhesive tape 1 (specifically, the tape main body 1A) can be attached to the curved surface of the adherend with the visibility of the tape main body 1A improved. Further, since the basis weight of the nonwoven fabric base material 2 is not more than the upper limit and the thickness of the nonwoven fabric base material 2 is not more than the upper limit, even when the double-sided adhesive tape 1 (specifically, the tape main body 1A) is bonded to a curved surface of an adherend, the elastic force of the nonwoven fabric base material 2 can be reduced, and the tape main body 1A can be inhibited from peeling from the adherend.

3. Modification example

As shown in fig. 1, the double-sided pressure-sensitive adhesive tape 1 includes a nonwoven fabric base material 2, a 1 st pressure-sensitive adhesive layer 3, a 2 nd pressure-sensitive adhesive layer 4, a 1 st release liner 5, and a 2 nd release liner 6, but the pressure-sensitive adhesive tape of the present invention is not particularly limited as long as it includes the nonwoven fabric base material 2 and the 1 st pressure-sensitive adhesive layer 3.

The pressure-sensitive adhesive tape may be composed of a nonwoven fabric base material 2 and a 1 st pressure-sensitive adhesive layer 3. The pressure-sensitive adhesive tape may be composed of a nonwoven fabric substrate 2, a 1 st pressure-sensitive adhesive layer 3 and a 1 st release liner 5. The pressure-sensitive adhesive tape may be composed of a nonwoven fabric base material 2, a 1 st pressure-sensitive adhesive layer 3 and a 2 nd pressure-sensitive adhesive layer 4. The pressure-sensitive adhesive tape may be composed of a nonwoven fabric base material 2, a 1 st pressure-sensitive adhesive layer 3, a 2 nd pressure-sensitive adhesive layer 4 and a 1 st release liner 5.

According to such a modification, the same effects as those of the above embodiment can be exhibited.

Examples

The present invention will be described more specifically below with reference to preparation examples, examples and comparative examples. The present invention is not limited to the preparation examples, examples and comparative examples. In addition, specific numerical values such as the blending ratio (content ratio), the physical property value, and the parameter used in the following description may be replaced with the upper limit (numerical value defined as "lower" or "insufficient") or the lower limit (numerical value defined as "upper" or "higher" of the above-mentioned description such as the blending ratio (content ratio), the physical property value, and the parameter corresponding thereto, described in the above-mentioned "embodiment".

< preparation of nonwoven Fabric substrate >

< preparation example 1 >

Relative to the nonwoven fabric A (material: pulp/rayon/vinylon binder, trade name: synthetic fiber paper black 14.0g/m²NIPPON PAPER PAPYLIA co., ltd., manufactured) 100 parts by mass, 1 part by mass of a black pigment (carbon black) was added, and the nonwoven fabric was dyed. Thus, a nonwoven fabric substrate was obtained. The air permeability of the nonwoven fabric base material, the basis weight of the nonwoven fabric base material, and the thickness of the nonwoven fabric base material are shown in table 1.

< preparation example 2 >

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²NIPPON PAPER PAPYLIA co., ltd.)) was changed to nonwoven fabric B (material: pulp, trade name: no.4134, manufactured by shifu paper products), a nonwoven fabric base was obtained in the same manner as in preparation example 1.

< preparation example 3 >

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²NIPPON PAPER PAPYLIA co., ltd.)) was changed to nonwoven fabric C (material: pulp, trade name: a nonwoven fabric substrate was obtained in the same manner as in preparation example 1, except for the use of NTO-16P-BLACK, manufactured by yofu paper corporation).

< preparation example 4 >

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²NIPPON PAPER PAPYLIA co., ltd.)) was changed to a nonwoven fabric D (material: pulp/rayon/vinylon binder, trade name: combination of Chinese herbsBlack fiber forming paper 30.0g/m²And NIPPON PAPER PAPYLIA co., ltd), a nonwoven fabric base was obtained in the same manner as in preparation example 1.

< preparation example 5 >

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²NIPPON PAPER PAPYLIA co., ltd.)) was changed to a nonwoven fabric E (material: a nonwoven fabric base was obtained in the same manner as in preparation example 1, except for pulp and Fujico co.

< preparation example 6 >

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²And NIPPON PAPER PAPYLIA co., ltd.)) was changed to a nonwoven fabric F, and a nonwoven fabric base was obtained in the same manner as in preparation example 1.

< preparation example 7 >

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²NIPPON PAPER PAPYLIA co., ltd.)) was changed to a nonwoven fabric G (material: polyester, trade name: PET paper 30g/m²And NIPPON PAPER PAPYLIA co., ltd), a nonwoven fabric base was obtained in the same manner as in preparation example 1.

< preparation example 8 >)

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²NIPPON PAPER PAPYLIA co., ltd.)) was changed to a nonwoven fabric H (material: pulp, trade name: a nonwoven fabric base was obtained in the same manner as in preparation example 1, except for F-18 processed paper and NIPPON PAPER PAPYLIA co.

< preparation example 9 >)

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²NIPPON PAPER PAPYLIA co., ltd.)) was changed to a nonwoven fabric I (material: pulp, trade name: MM base paper, manufactured by sanmu specialty paper co., ltd), a nonwoven fabric base was obtained in the same manner as in preparation example 1.

< preparation example 10 >)

Nonwoven fabric A (trade name: synthetic fiber paper black 14.0 g/m)²、NIPPON PAPER PAPYLIA co., ltd, manufactured)) was changed to a nonwoven fabric J (material: pulp, trade name: a nonwoven fabric substrate was obtained in the same manner as in preparation example 1, except for the use of NTO-16P-BLACK, manufactured by yofu paper corporation).

< examples 1 to 5 and comparative examples 1 to 4 >

60 parts by mass of distilled water and 0.1 part by mass of an emulsifier (sodium polyoxyethylene alkyl ether sulfate, trade name: LATEMUL E-118B, manufactured by Kao corporation) were charged into a reaction vessel. The reaction vessel was equipped with a vessel main body, a stirrer, a thermometer, a reflux condenser, a dropping device, and a nitrogen gas inlet tube.

Then, 0.1 part by mass of a polymerization initiator (2, 2' -azobis [ N- (2-carboxyethyl) -2-methylpropionamidine ] hydrate, trade name: VA-057, manufactured by Wako pure chemical industries, Ltd.) was added to the reaction vessel.

Further, 85 parts by mass of 2-ethylhexyl acrylate, 13 parts by mass of methyl acrylate, 1.5 parts by mass of acrylic acid, 0.5 part by mass of methacrylic acid, 0.02 part by mass of 3-methacryloxypropyltrimethoxysilane (trade name: KBM-503, manufactured by shin-Etsu chemical Co., Ltd.), 0.033 part by mass of a chain transfer agent (dodecylmercaptan), 1.9 parts by mass of the above emulsifier, and 28.6 parts by mass of distilled water were mixed and emulsified to prepare an emulsion.

Then, the temperature of the emulsion was adjusted to 60 ℃. Thereafter, the emulsion was slowly dropped into the above reaction vessel over 4 hours to carry out emulsion polymerization. Thereafter, the reaction solution was stirred at 60 ℃ for 3 hours, and the heating of the reaction solution was stopped.

Then, 0.75 part by mass of 10% by mass hydrogen peroxide water was added to the reaction solution. Thereafter, the reaction solution was stirred for 5 minutes. Subsequently, 0.5 part by mass of sodium ascorbate was added to the reaction solution to conduct redox treatment. Thereafter, the reaction solution was cooled to room temperature (25 ℃ C.). To the cooled reaction solution, 10 mass% ammonia water was added to adjust the pH of the reaction solution to 6.5.

Thus, a (meth) acrylic polymer emulsion was obtained. The solid content concentration (NV) of the (meth) acrylic polymer emulsion was about 51 mass%. The average particle size of the emulsion was about 200 nm.

Next, 10 parts by mass (in terms of solid content) of 1 st water-dispersible rosin resin (trade name: Super ester KE-802, manufactured by Mitsuwa chemical industries, Ltd.) and 10 parts by mass of 2 nd water-dispersible rosin resin (trade name: Super ester NS-100H, manufactured by Mitsuwa chemical industries, Ltd.) were added to the (meth) acrylic polymer emulsion.

Thereafter, a pH adjuster (10 mass% aqueous ammonia) and a thickener (polyacrylic acid) were added to the (meth) acrylic polymer emulsion. The pH of the (meth) acrylic polymer emulsion was 7.2. The viscosity of the (meth) acrylic polymer emulsion was 8 pas.

Next, the (meth) acrylic polymer emulsion was coated on the surface of a No. 1 release liner (trade name: SLB-80WD (V2), Kaito Chemical Industry Co., Ltd.). The front and back surfaces of the 1 st release liner were treated with a silicone release agent.

Thereafter, the coating film of the (meth) acrylic polymer emulsion was dried at 100 ℃ for 2 minutes. Thereby, a 1 st pressure-sensitive adhesive layer formed of the water-dispersed acrylic pressure-sensitive adhesive composition was formed. The thickness of the 1 st pressure-sensitive adhesive layer was about 60 μm.

Next, the 1 st pressure-sensitive adhesive layer on the 1 st release liner was disposed on the nonwoven fabric so that the 1 st pressure-sensitive adhesive layer was in direct contact with the surface of the nonwoven fabric of each preparation example. Thus, the nonwoven fabric, the 1 st pressure-sensitive adhesive layer, and the 1 st release liner are laminated in this order in the thickness direction of the nonwoven fabric.

Subsequently, a (meth) acrylic polymer emulsion to which a water-dispersible rosin resin, a pH adjuster, and a thickener are added is directly applied to the back surface of the nonwoven fabric. Thereafter, the coating film of the (meth) acrylic polymer emulsion was dried at 100 ℃ for 2 minutes. Thereby, a 2 nd pressure-sensitive adhesive layer formed of the water dispersion type acrylic pressure-sensitive adhesive composition was formed. The thickness of the 2 nd pressure-sensitive adhesive layer was about 60 μm.

Thereafter, a 2 nd release liner was attached to the 2 nd pressure-sensitive adhesive layer on the opposite side of the nonwoven fabric substrate. Thus, a laminate was obtained. The laminate comprises a 1 st release liner, a 2 nd pressure-sensitive adhesive layer, a nonwoven fabric, a 1 st pressure-sensitive adhesive layer and a 1 st release liner in this order in the thickness direction of the nonwoven fabric. Thereafter, the laminate was held in an oven at 50 ℃ for 24 hours.

Thereby, a double-sided pressure-sensitive adhesive tape was obtained.

< comparative example 5 >

A double-sided pressure-sensitive adhesive tape was obtained in the same manner as in example 1, except that the water-dispersed acrylic pressure-sensitive adhesive composition contained a black pigment and the nonwoven fabric substrate a of preparation example 1 was changed to the nonwoven fabric substrate C of preparation example 3. The black pigment is added to the (meth) acrylic polymer emulsion. The black pigment was added in an amount of 10 parts by mass per 100 parts by mass of the (meth) acrylic monomer.

Evaluation of

(visibility)

The double-sided pressure-sensitive adhesive tapes of the examples and comparative examples were cut into a size of 10cm × 10 cm. Then, the 1 st release liner was peeled off from the 1 st pressure-sensitive adhesive layer. Next, the 1 st pressure-sensitive adhesive layer was attached to a white polystyrene film. The white polystyrene film has L^＊：88.85、a^＊：0.45、b^＊: a hue of 5.76.

Then, the 2 nd release liner is peeled off from the 2 nd pressure-sensitive adhesive layer. Next, the color tone of the double-sided pressure-sensitive adhesive tape (tape main body) was measured from the opposite side of the nonwoven fabric base material with respect to the 2 nd pressure-sensitive adhesive layer. The color tone was measured by a multi-angle spectrophotometer (MA68II, manufactured by X-rite Co.). The measurement angle was 45 °.

Then, the color tone of the double-sided pressure-sensitive adhesive tape was evaluated according to the following criteria. The results are shown in table 1.

〇：L^＊Is 40 or less.

×：L^＊Over 40.

(sealing Property (rebound resistance))

The adhesiveness (repulsion resistance) of the double-sided pressure-sensitive adhesive tapes of the examples and comparative examples was evaluated by the repulsion resistance test (foam repulsion resistance test) described in Japanese patent laid-open No. 2015-218283.

In detail, in the double-sided pressure-sensitive adhesive tapes of the examples and comparative examples, the 1 st release liner was peeled from the 1 st pressure-sensitive adhesive layer. Then, a flexible urethane foam (trade name: ECS (gray)) was attached to the 1 st pressure-sensitive adhesive layer. Thereafter, a 1kg roller was brought into contact with the flexible urethane foam from the opposite side of the 1 st pressure-sensitive adhesive layer, and the 1kg roller was reciprocated once.

Thus, a laminate was obtained. The laminate comprises a 2 nd release liner, a 2 nd pressure-sensitive adhesive layer, a nonwoven fabric base material, a 1 st pressure-sensitive adhesive layer and a flexible urethane foam in this order.

Subsequently, the laminate was held at 23 ℃ for 24 hours. Then, the laminate was cut into a size of 10mm in width by 50mm in length. Thus, a sample was obtained.

Then, for the sample, the 2 nd release liner was peeled off from the 2 nd pressure-sensitive adhesive layer. Next, an ABS sheet was attached to the 1 st portion of the 2 nd pressure-sensitive adhesive layer up to 10mm in the longitudinal direction of the sample. Thereafter, a 2kg roller was brought into contact with the ABS sheet from the opposite side of the 2 nd pressure-sensitive adhesive layer, and the 2kg roller was reciprocated once.

Next, the sample was folded, and the 2 nd part except the 1 st part in the 2 nd pressure-sensitive adhesive layer was attached to the back surface of the ABS panel. Thereafter, the sample attached to the ABS plate was left to stand at 23 ℃ and 50% RH for 24 hours.

After that, the adhesiveness (repulsion resistance) of the double-sided pressure-sensitive adhesive tape was evaluated by whether or not the 1 st part of the 2 nd pressure-sensitive adhesive layer was peeled off from the ABS sheet. When the 1 st part of the 2 nd pressure-sensitive adhesive layer was peeled from the ABS sheet, the adhesiveness (repulsion resistance) of the double-sided pressure-sensitive adhesive tape was evaluated as ×. In the case where the 1 st part of the 2 nd pressure-sensitive adhesive layer was not peeled from the ABS sheet, the adhesiveness (repulsion resistance) of the double-sided pressure-sensitive adhesive tape was evaluated to be good. The results are shown in table 1.

[ Table 1]

TABLE 1

The present invention is provided as an exemplary embodiment of the present invention, but this is merely an example and is not to be construed as limiting. Variations of the invention that are obvious to those skilled in the art are intended to be included within the scope of the foregoing claims.