Adhesive tape

Abstract

An adhesive tape in which lamination peeling is not likely to occur even if the lamination layer is thinned comprises: a substrate 1 of a longitudinal fabric, in which a weft yarn 11 is inserted into a yarn loop structure formed by a multifilament warp yarn 12; a first lamination layer 2, formed on a first side 1A in which one warp yarn is exposed on the weft yarn surface of the substrate 1; a second lamination layer 3, formed on a second side 1B in which two warp yarns are exposed on the weft yarn surface of the substrate 1; and an adhesive layer 6, formed on the first lamination layer side 2.

Description

Technical Field

[0001] The present invention relates to an adhesive tape suitable for use as a packaging material or a curing material. Background Art

[0002] High-adhesive adhesive tapes are widely used for fixing, bundling, or painting masking of materials in a wide range of fields such as agriculture, civil engineering, construction, and transportation. In addition, such adhesive tapes are required to have appropriate base material strength and hand-tearability for ease of handling.

[0003] Patent Document 1 discloses such a pressure-sensitive adhesive tape with improved hand-tearability.

[0004] Patent document 1 discloses an adhesive tape which is obtained by inserting a flat yarn made of a thermoplastic resin as a main material as a transverse yarn into a longitudinal yarn formed by independently weaving a multifilament yarn, forming a chemical or physical anchoring treatment layer on one side or the front and back sides of the woven fabric thus formed, laminating a thermoplastic resin on one side or both sides in a molten state or a dry film state on the anchoring treatment layer, and coating a pressure-sensitive adhesive on one side or both sides of the woven fabric substrate thus obtained, and the longitudinal / transverse tensile strength, longitudinal / transverse tear strength, and longitudinal elongation are specified as specific values.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2002-294189 Summary of the invention

[0008] Problems to be solved by the invention

[0009] Conventional pressure-sensitive adhesive tapes generally have a structure in which the surface of the base fabric as described above is covered with a laminate layer of a thermoplastic resin and a pressure-sensitive adhesive layer is formed via a primer layer.

[0010] When the adhesive tape is attached to an adhered object and then peeled off, sometimes the adhesive remains on the adhered object (hereinafter, this phenomenon is also referred to as "adhesive residue"), or the laminate layer peels off and remains on the adhered object together with the adhesive. The phenomenon of laminate layer peeling off is called "laminate peeling". In the case of adhesive residue, it can be removed by wiping with alcohol or the like, but in the case of laminate peeling, sometimes the adhesive is covered by the laminate layer residue, making it difficult to wipe with alcohol or the like.

[0011] In order to prevent such lamination peeling, measures such as increasing the thickness of the lamination layer are taken. However, if the lamination layer is thickened, the winding diameter and the tape weight increase at the same tape length, and the cost also increases.

[0012] Therefore, an object of the present invention is to provide an adhesive tape that is less likely to undergo laminate peeling even when the laminate layer is thinned.

[0013] Means for Solving the Problem

[0014] The present inventors have found that by specifically defining the structure on the side where the adhesive layer is formed in the base fabric, an adhesive tape less likely to undergo laminate peeling can be obtained.

[0015] That is, the present invention relates to an adhesive tape having:

[0016] A base material of a warp-knitted fabric in which a weft yarn is inserted into a loop structure formed by multifilament warp yarns;

[0017] A first laminate layer formed on a first surface where one warp yarn is exposed on the surface of the weft yarn of the base material;

[0018] A second laminate layer formed on a second surface where two warp yarns are exposed on the surface of the weft yarn of the base material; and

[0019] An adhesive layer formed on the side of the first laminate layer.

[0020] Advantages of the Invention

[0021] In the present invention, the number of warp yarns exposed on the surface of the weft yarn on the first surface of the warp-knitted fabric forming the first laminate layer is relatively small. As a result, the contact area between the weft yarn and the laminate layer increases, and laminate peeling is suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic plan view (a) of a warp-knitted fabric used in one embodiment of the present invention, and a schematic cross-sectional view (b) taken along line A-A'.

[0023] Figure 2 It is a schematic cross-sectional view showing the cross-sectional structure of an adhesive sheet according to one embodiment of the present invention.

[0024] Figure 3 It is a view for explaining the manufacturing process of an adhesive sheet according to one embodiment of the present invention.

[0025] Figure 4 It is a process cross-sectional view for explaining the manufacturing process of an adhesive sheet according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0026] An adhesive tape according to one embodiment of the present invention comprises: a substrate of a longitudinal fabric in which weft yarns are inserted into a yarn loop structure formed by warp yarns of a multifilament; a first laminate layer formed on a first side of the substrate on which one warp yarn is exposed on the weft yarn surface; a second laminate layer formed on a second side of the substrate on which two warp yarns are exposed on the weft yarn surface; and an adhesive layer formed on the side of the first laminate layer.

[0027] Hereinafter, each configuration will be described.

[0028] <Base material (vertical fabric)>

[0029] The adhesive tape according to one embodiment of the present invention uses, as a base material, a longitudinal woven fabric in which weft yarns are inserted into a loop structure formed by multifilament warp yarns. Figure 1 The schematic top view (a) and the schematic cross-sectional view (b) at the line A-A' of a longitudinal fabric 1 used in one embodiment of the present invention show a structure in which independent chain stitches 13 are formed by multifilament warp yarns 12 and weft yarns 11 are inserted transversely therein. As shown in the schematic cross-sectional view (b), in each independent chain stitch 13, the surface with one warp yarn 12 is referred to as the first surface 1A, and the surface with two warp yarns 12 is referred to as the second surface 1B.

[0030] exist Figure 1 In the figure, as a loop structure based on warp yarns, an independent chain stitch structure in which warp yarns are connected in the longitudinal direction (up and down direction on the paper surface) is shown, but it is not limited to this. For example, it can also be a single-bar warp plain weave structure as shown in Japanese Patent Publication No. 2014-210998. Other known loop structures can also be used. In any case, the loop structure formed by the warp yarns can be formed in a manner that forms a surface in which one warp yarn is exposed and a surface in which two warp yarns are exposed in each loop structure.

[0031] (Warp)

[0032] As the warp yarn, there is no particular limitation as long as it is a material used in the art, for example, polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate (PET), polyacrylic resins, polyamide resins such as nylon, etc. can be used. Multifilaments formed by these resins are used as warp yarns, but in terms of their fineness, the balance of base material strength, hand tearability, and elongation is good for those with 10 to 1000 deniers (1.11 to 111 tex), preferably 20 to 500 deniers (2.22 to 55.5 tex). The warp density of the warp yarn can be set to 10 to 40 strands / inch.

[0033] (Weft Yarn)

[0034] As the weft yarn, as long as it is a material used in the art, there is no particular limitation, and the same thermoplastic resin as the above-mentioned warp yarn can be used. It is preferred to use a flat yarn obtained by processing the film obtained by melt-extruding these thermoplastic resins from a T-die or a circular die into a narrow width. Modifiers such as anti-aging agents and antistatic agents can be added as needed. In addition, its fineness is preferably 50 to 1000 deniers (5.55 to 111 tex) from the balance between the hand-tearability in the longitudinal direction and the thermal degradation during lamination, and more preferably 100 to 500 deniers (11.1 to 55.5 tex). In addition, as the weft density of the weft yarn, it can be set to 8 to 28 strands / inch.

[0035] <Adhesive tape>

[0036] Figure 2 This is a cross-sectional view of a tape having an adhesive layer 6 formed on one side of the adhesive tape of the present invention, wherein a first laminate layer 2 is formed on the first side 1A of the longitudinal fabric 1, and a second laminate layer 3 is formed on the second side 1B, and an adhesive layer 6 is provided on the side of the first laminate layer 2. Here, although a primer layer 4 is provided between the first laminate layer 2 and the adhesive layer 6, and a back agent layer 5 is provided on the surface of the second laminate layer 3 opposite to the adhesive layer 6, these layers are arbitrary layers. When the tape is wound and formed into a roll, it can be wound with release paper or a release film interposed on the surface in contact with the adhesive layer 6, or a release layer can be formed as the back agent layer 5.

[0037] (Lamination layer)

[0038] In order to prevent lamination peeling, the lamination layer is preferably made of the same resin material as the weft yarn. The coating amount per single side can be 50 to 250 g / m2 depending on the purpose. 2 The thickness can be selected from the range of 5 to 300 μm. In the present invention, even if the laminated layer, especially the first laminated layer that is prone to laminated delamination, is formed thin, laminated delamination is not likely to occur.

[0039] use Figure 3 and Figure 4 A method for forming the laminate layer will be described.

[0040] First, a physical or chemical surface treatment (anchoring treatment) is applied to the first surface 1A of the longitudinal fabric 1 serving as the substrate. Examples of the physical treatment include corona treatment, UV treatment, sputtering treatment, and the like, and examples of the chemical treatment include coating treatment with a resin selected from organic titanium, isocyanate, polyethyleneimine, polybutadiene, and the like. Figure 37 shows the treatment method using the corona treatment device 7. Next, using the extrusion laminator 8, the resin material 14 is supplied from the extruder 9 to the first surface 1A of the longitudinal fabric 1 via the T-die 10, and the resin material 14 is pressed against the cooling roller 16 together with the longitudinal fabric 1 by the rubber pressure roller 15, and is bonded to the longitudinal fabric 1. Here, when bonding the resin material 14 to the first surface 1A, a so-called rough surface roller having a concave-convex surface is used as the cooling roller 16, so that Figure 4 As shown in (a), a first laminate layer 2 having a matte surface 2A is formed on a first surface 1A.

[0041] Next, the front and back sides are turned over, and the second side 1B of the longitudinal fabric 1 is subjected to surface treatment and lamination of the resin material 14 in the same manner as the first side 1A. As the cooling roll 16 in this case, a so-called mirrored roll having a mirror-finished surface is used, so that Figure 4 As shown in (b), a second laminate layer 3 having a smooth surface is formed.

[0042] Here, when the second surface 1B of the warp fabric 1 is pressed against the mirror-finished roller by the rubber press roller 15, the nap surface 2A in contact with the press roller 15 becomes the first laminated layer 2 having the uneven surface 2B reflecting the unevenness of the warp yarns.

[0043] In this way, by making the surface of the first lamination layer into an uneven surface, the contact area when the adhesive layer 6 is formed can be increased and adhesive residue can be effectively suppressed.

[0044] (Primer layer)

[0045] In order to improve the adhesion with the adhesive layer, a primer layer can be formed on the surface of the first laminate layer formed as described above. As the primer, various elastomers (for example, copolymers of ethylene and vinyl acetate, chlorinated polypropylene, reactants of styrene-butadiene copolymers and phenolic resins, butyl acrylate, vinyl acetate, acrylamide, reactants of natural rubber or synthetic rubber, etc.) and various primers can be cited. In addition, the surface of the first laminate layer can be modified by corona treatment, etching treatment, plasma treatment, sandblasting, etc. instead of forming the primer layer.

[0046] (Adhesive layer)

[0047] As adhesive, it is appropriate to select and use from known adhesive composition in the mode of becoming the desired adhesive force.The adhesive layer comprises the base polymer (referred to as adhesive base polymer) as adhesive component.The above-mentioned adhesive base polymer is not particularly limited, and acrylic adhesive and rubber adhesive can be used.As the above-mentioned acrylic adhesive, for example, can be enumerated: by using (meth) acrylate monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate as main component, and make (meth) acrylic acid, crotonic acid, fumaric acid, itaconic acid, maleic acid (anhydride) etc. contain the monomer of functional group, vinyl acetate, acrylonitrile, styrene, 2-hydroxyethyl (meth) acrylate, 2-hydroxymethyl ethyl acrylamide etc. and this main component to copolymerize and obtain acrylic adhesive.

[0048] Examples of the rubber adhesive include those obtained by mixing one or a combination of two or more of the elastomer components such as natural rubber, styrene-butadiene rubber, butyl rubber, isoprene rubber, butadiene rubber, and styrene-isoprene block copolymers with rosin-based resins, terpene-based resins, aliphatic petroleum resins, aromatic petroleum resins, copolymer-based petroleum resins, alicyclic petroleum resins, coumarone-indene resins, pure monomer-based resins, phenolic resins, xylene resins, and the like.

[0049] In addition to the adhesive base polymer, the adhesive layer may also contain various additives known in the art. Such additives may include one or a combination of two or more of various additives such as a crosslinking agent, a flame retardant, an antioxidant, a weathering agent, a softener, a stabilizer, a filler, an extender, and a reinforcing agent.

[0050] The thickness of the adhesive layer can be appropriately set according to the purpose and the components of the adhesive used, and can be formed, for example, in the range of 5 to 200 μm. The adhesive layer can be formed by directly coating the first laminate layer using various coating devices, or by coating the first laminate layer with the primer layer or surface treatment. Examples of coating devices include: a roll coater, a die coater, a die lip coater, a Meyer rod coater, a gravure coater, and the like.

[0051] (Back side treatment)

[0052] When the tape is wound, the second laminate layer side surface in contact with the adhesive layer is coated with various release agents as a back surface treatment. Examples of the release agent include long-chain alkyl release agents (copolymers of stearyl acrylate and acrylic acid, vinyl acetate or acrylonitrile, copolymers of stearyl acrylamide and acrylonitrile, acrylic acid, copolymers of stearyl vinyl ether and acrylic acid, maleic anhydride, acrylonitrile), addition reaction type, condensation reaction type, cationic polymerization type, free radical polymerization type silicone release agents, and the like.

[0053] These release agents can also be formed by coating using the above-mentioned various coating devices.

[0054] Example

[0055] Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to these examples.

[0056] Example 1

[0057] A 30 denier (3.3 tex) polyester multifilament yarn was used as the warp yarn, and a 300 denier (33 tex) high-density polyethylene flat yarn was used as the weft yarn, such as Figure 1 As shown, the base material is knitted into a longitudinal fabric with warp yarns forming an independent chain stitch structure.

[0058] Next, a resin layer is formed on both the front and back sides of the woven base material to produce a laminated tape. The resin layer is made of polyethylene resin. First, a transparent polyethylene resin is melt-extruded from a T-die onto the first side 1A of the base material stretched between two rubber rollers, and pressurized by a matte roller. Next, after the front and back sides are reversed, the polyethylene resin layer extruded from the T-die is similarly laminated on the second side 1B. It should be noted that a mirror roller is pressed against the second side and pressurized.

[0059] In addition, in the following description, the side where the pressure-sensitive adhesive layer is formed is referred to as the first layer, and the opposite side is referred to as the second layer.

[0060] The first layer (the first laminate layer of the present invention) was formed to have a thickness of 30 μm, and the second layer (the second laminate layer of the present invention) was formed to have a thickness of 33 μm.

[0061] Next, after forming a primer layer of ethylene-vinyl acetate copolymer on the first layer side, an acrylic adhesive was applied by a roll coater to form an adhesive layer having a thickness of 35 μm, thereby producing an adhesive tape of Example 1. The tape configuration is shown in Table 1.

[0062] Comparative Example 1

[0063] The pressure-sensitive adhesive tape of Comparative Example 1 was produced in the same manner as in Example 1, except that the first layer was formed on the second surface of the substrate and the second layer was formed on the first surface.

[0064] Comparative Example 2

[0065] Except having changed the thickness of the lamination layer as shown in Table 1, it carried out similarly to Comparative Example 1, and produced the adhesive tape.

[0066] [Table 1]

[0067] <Belt composition>

[0068]

[0069] Next, the lamination peeling of the obtained pressure-sensitive adhesive tape was evaluated. The evaluation method was carried out in accordance with the adhesive strength measurement test of JIS Z 0237. The evaluation criteria were as follows. The results are shown in Table 2.

[0070] ○: No lamination peeling

[0071] △: Lamination peeling less than 5%

[0072] ×: Lamination peeling 5% to less than 30%

[0073] ××: Lamination peeling 30% to less than 80%

[0074] ×××: Lamination peeling is more than 80%

[0075] [Table 2]

[0076]

[0077] As shown in Example 1, for the adhesive tape of the present invention in which a first lamination layer is formed on the first side of a substrate and an adhesive layer is formed thereon, lamination peeling can be effectively suppressed even if the first lamination layer is thinned. For Comparative Example 1 in which a thin lamination layer is formed on the second side of the substrate, a large amount of lamination peeling was observed. Therefore, it is necessary to form the lamination layer thickly as in Comparative Example 2.

[0078] Description of Reference Numerals

[0079] 1 Vertical fabric

[0080] 11 Weft

[0081] 12 Warp

[0082] 13 Independent Chain Stitches

[0083] 1A Page 1

[0084] 1B Side 2

[0085] 2 First lamination layer

[0086] 3 Second lamination layer

[0087] 4 Primer layer

[0088] 5 Back coating

[0089] 6 Adhesive layer

[0090] 7 Corona treatment device

[0091] 8 Extrusion Laminator

[0092] 9 Extruder

[0093] 10 T-type mold

[0094] 14. Resin material

[0095] 15. Pressing roller (rubber)

[0096] 16 Cooling roller

Claims

1. An adhesive tape comprising: A base material of a longitudinal fabric having weft yarns inserted in a loop structure formed by multifilament warp yarns; A first laminate layer formed on a first side of the base material where one warp yarn is exposed on the weft yarn surface; A second laminate layer formed on a second side of the base material where two warp yarns are exposed on the weft yarn surface; as well as an adhesive layer formed only on the first laminating layer side, The first laminate layer has a concave-convex surface reflecting the concave-convex of the warp yarns, The fineness of the weft yarn is 11.1 tex to 55.5 tex.

2. The adhesive tape according to claim 1, wherein The yarn loop structure is an independent chain stitch.

3. The adhesive tape according to claim 1 or 2, wherein The weft yarns are flat yarns.

4. The adhesive tape according to claim 3, wherein The flat yarn is a polyethylene flat yarn.

5. The adhesive tape according to claim 4, wherein The first laminate layer and the second laminate layer include polyethylene.

6. The adhesive tape according to claim 1 or 2, wherein The warp yarn is a multifilament made of polyester.

7. The adhesive tape according to claim 1 or 2, wherein A primer layer is provided between the adhesive layer and the first laminating layer.

8. The adhesive tape according to claim 1 or 2, wherein The second laminating layer has a back surface agent layer on its surface, and the pressure-sensitive adhesive tape is held in a roll form with the back surface agent layer facing outward.

9. The adhesive tape according to claim 1 or 2, wherein The thickness of the first lamination layer is in the range of 5 μm to 30 μm.

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