Self-adhesive tape

Abstract

To provide an autohesion tape high in adhesive strength, capable of being unwound easily, and having water resistance and writing ability.SOLUTION: In an autohesion tape in which an anchor agent layer 2 and an autohesion agent layer 3 are laminated on one side of a substrate 1 in this order, the autohesion force between the autohesion agent layers 3 is 1.2 N / 6 mm or more, and the adhesive force between the autohesion agent layer 3 and the substrate 1 is 0.4 N / 15 mm or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a self-adhesive tape that adheres by overlapping and pressing adhesive-coated surfaces together.

Background Art

[0002] Conventionally, self-adhesive tapes used for tying bundles such as fruits and fresh flowers or for tagging with information about articles have been known (see, for example, Patent Documents 1 and 2). The self-adhesive tape has a configuration in which a self-adhesive that adheres under a light pressure is applied to one side of a long base material, and by overlapping and pressing the adhesive-coated surfaces together, it has a function of adhering only the pressed portion.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] The self-adhesive tape is made into a coil-shaped product. The user unwinds the self-adhesive tape and cuts it to a length suitable for use, and for example, winds it around the stem of a bouquet of fresh flowers and adheres it by overlapping and pressing the adhesive-coated surfaces at both ends of the self-adhesive tape together.

[0005] In such a self-adhesive tape, it is important not only to be able to firmly adhere the self-adhesive tapes together, but also to be able to easily unwind the self-adhesive tape. In addition, since a bouquet of flowers is placed in water, it is required to have water resistance, and furthermore, since necessary items may be written with a writing instrument such as a pencil, writing property is also required.

[0006] Therefore, the present invention aims to provide a self-adhesive tape that has high adhesive strength, can be easily unrolled, and is also water-resistant and writable. [Means for solving the problem]

[0007] The present invention relates to a self-adhesive tape in which an anchoring agent layer and a self-adhesive layer are laminated in that order on one side of a substrate, wherein the self-adhesive force between the self-adhesive layers is 1.2 N / 6 mm or more, and the adhesive force between the self-adhesive layers and the substrate is 0.4 N / 15 mm or less.

[0008] In the present invention, it is preferable that the anchoring agent is a polyolefin resin obtained by mixing a polyether urethane with a polyolefin resin in a weight ratio of 75 / 25 to 80 / 20.

[0009] Furthermore, the self-adhesive agent consists of a natural rubber latex concentrate and a modified styrene-butadiene copolymer as a binder, and amorphous silica as a filler, with a filler / binder ratio of preferably 0.044 to 0.066.

[0010] Furthermore, it is desirable that the self-adhesive agent contains 5 to 10 parts of modified styrene-butadiene copolymer per 100 parts by weight of natural rubber latex stock.

[0011] The base material is preferably synthetic paper, and more preferably made primarily from polypropylene resin and having numerous fine pores. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a self-adhesive tape that has high self-adhesion strength, can be easily unwound, and is also water-resistant and writable. [Brief explanation of the drawing]

[0013] [Figure 1] This is a cross-sectional view showing a self-adhesive tape according to an embodiment of the present invention. [Figure 2]This is a photograph showing an adhesion test in an embodiment of the present invention. [Modes for carrying out the invention]

[0014] More preferred embodiments of the present invention will be described in detail below. Figure 1 is a cross-sectional view of the self-adhesive tape according to the embodiment. As shown in Figure 1, the self-adhesive sheet laminate is constructed by providing an anchoring agent layer 2 on one side of a base material 1, and providing a self-adhesive layer 3 on the anchoring agent layer 2.

[0015] The base material 1 is made of synthetic paper. As for the synthetic paper, an unstretched type can be used, which is made by mixing synthetic resin with additives such as fillers, melt-kneading it in an extruder, and then extruding it through a die slit to form a film, or a biaxially oriented type that is subsequently subjected to biaxial stretching. In the biaxially oriented type, fine pores can be formed inside.

[0016] Furthermore, synthetic paper is not limited to the film-like materials described above, but also includes paper made from synthetic fibers. Suitable synthetic fibers include polyester fibers such as polyamide fibers and polyethylene terephthalate fibers (hereinafter also referred to as PET or PET fibers), polyolefin fibers such as acrylic fibers, polyethylene fibers, and polypropylene fibers, aramid fibers, polyethylene naphthalate fibers, polybutylene terephthalate fibers, polyphenylene sulfide fibers (hereinafter also referred to as PPS fibers), polyacetal fibers, liquid crystal polymer fibers, and polyimide fibers. These synthetic fibers can be used individually, but two or more types can also be used in combination. Additionally, synthetic paper can also be made by laminating a resin film onto both sides of conventional paper. The film has numerous pores.

[0017] As an anchoring agent, a mixture of polyolefin resin and polyether urethane in a weight ratio of 75 / 25 to 80 / 20 is preferably used. Here, examples of polyolefins include homopolymers or copolymers of olefins selected from ethylene, propylene, butene, 3-methyl-1-butene, 3-methyl-1-heptene, etc., and copolymers of said olefins with vinyl acetate, butadiene, acrylic acid esters, methacrylic acid esters, etc. Specifically, chlorinated polyethylene, chlorinated polypropylene, chlorinated ethylene-propylene copolymer, chlorinated ethylene-vinyl acetate copolymer, etc. are preferred.

[0018] Polyether urethanes are combinations of isocyanates and polyols. The isocyanates include aliphatic diisocyanate compounds such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, dimer acid diisocyanate, and lysine diisocyanate, and alicyclic diisocyanate compounds such as isophorone diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), methylcyclohexane-2,4-(or-2,6-)diisocyanate, 1,3-(or 1,4-)di(isocyanatomethyl)cyclohexane, 1,4-cyclohexane diisocyanate, 1,3-cyclopentane diisocyanate, and 1,2-cyclohexane diisocyanate. Examples include aromatic diisocyanate compounds such as xylylene diisocyanate, metaxylylene diisocyanate, tetramethylxylylene diisocyanate, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, 1,4-naphthalene diisocyanate, 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether isocyanate, (m- or p-)phenylene diisocyanate, 4,4'-biphenylene diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, bis(4-isocyanatophenyl)sulfone, and isopropylidenebis(4-phenylisocyanate).

[0019] Examples of the polyol include polyether polyols such as polyethylene glycol, polypropylene glycol, polyethylene-propylene (block or random) glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol, and polyoctamethylene ether glycol.

[0020] The self-adhesive layer 3 is selected from self-adhesives that hardly adhere to most substances in a normal state and adhere to each other under pressure. For example, the main agents of the self-adhesive include vinyl chloride resins, vinylidene chloride resins, synthetic rubber resins, natural rubber latex stock solutions, natural rubber latex systems, acrylic resins, and the like. Considering the balance between performance and cost, a natural rubber latex stock solution is preferred.

[0021] The binder in the self-adhesive layer 3 contributes to preventing the filler from falling off and improving the adhesion to the substrate. Examples include acrylic copolymers, acrylonitrile-butadiene rubber (NBR), styrene-butadiene rubber (SBR), chloroprene rubber, and modified styrene-butadiene copolymers. Among them, modified styrene-butadiene copolymers are preferred.

[0022] As the filler in the self-adhesive layer 3, inorganic fillers such as talc, silica, calcium carbonate, and aluminum hydroxide, and organic fillers such as wheat starch, corn starch, and coconut starch are used. As the filler, amorphous silica is preferred. Here, the filler / binder ratio is preferably 4.2 / 95.8 to 6.2 / 93.8.

[0023] If necessary, additives such as preservatives, deodorants, defoamers, ultraviolet absorbers, antioxidants, surfactants, curing agents, antistatic agents, dispersants, thickeners, mold release agents, fluorescent dyes, colored dyes, dye fixatives, and ink fixatives may be added to the self-adhesive layer 3.

[0024] The self-adhesive tape with the above configuration has a self-adhesive force of 1.2 N / 6 mm or more between the self-adhesive layers and an adhesive force of 0.4 N / 15 mm or less between the self-adhesive layer and the base material, thus providing high self-adhesive strength while being easy to unwind. Furthermore, by using synthetic paper as the base material, it is water-resistant, and by providing fine pores in the base material, it can be written on. [Examples]

[0025] The configuration and effects of the present invention will be specifically described below with reference to examples, but the present invention is not limited in any way to these examples.

[0026] 1. Making self-adhesive tape <Example 1> Basis weight 66.4g / m 2 The base material is synthetic paper, and on one side of this base material, an anchoring agent, which is a mixture of polyolefin resin and polyether urethane in a weight ratio of 75 / 25 to 80 / 20, is applied by reverse roll coater with a drying amount of 1.5 g / m². 2 The coating was applied in this manner. Next, the self-adhesive coating paint described below was applied to the anchoring agent layer using a reverse roll coater, with a dry coating amount of 8g / m². 2 The tape was applied in this manner to create a self-adhesive tape.

[0027] Self-adhesive coating Natural rubber latex concentrate, 100 parts by weight Modified styrene-butadiene copolymer 7.5 parts by weight Amorphous silica 6 parts by weight

[0028] <Example 2> A self-adhesive tape according to Example 2 of the present invention was prepared in the same manner as in Example 1, except that the coating for the self-adhesive layer was changed to the one described below. Self-adhesive coating Natural rubber latex concentrate, 100 parts by weight Modified styrene-butadiene copolymer 5 parts by weight Amorphous silica 6 parts by weight

[0029] <Example 3> An example of the present invention, specifically Example 3, was prepared in the same manner as in Example 1, except that the coating for the self-adhesive layer was changed to the one described below. Self-adhesive coating Natural rubber latex concentrate, 100 parts by weight Modified styrene-butadiene copolymer 10 parts by weight Amorphous silica 6 parts by weight

[0030] <Comparative Example 1> Comparative Example 1 was prepared in the same manner as in Example 1, except that the paint for the anchoring agent layer was changed to chlorinated polyolefin (Superclon 390S, manufactured by Nippon Paper Industries).

[0031] <Comparative Example 2> A self-adhesive tape for Comparative Example 2 was prepared in the same manner as in Example 1, except that it did not have an anchoring agent layer.

[0032] <Comparative Example 3> A self-adhesive tape for Comparative Example 3 was prepared in the same manner as in Example 1, except that the base material was changed to polyethylene terephthalate (PET) resin.

[0033] <Comparative Example 4> Base material with a basis weight of 70 g / m² 2 A self-adhesive tape for Comparative Example 4 was prepared in the same manner as in Example 1, except that it was changed to bleached kraft paper.

[0034] <Comparative Example 5> A self-adhesive tape of Comparative Example 5 of the present invention was prepared in the same manner as in Example 1, except that the coating for the self-adhesive layer was changed to the one described below. Self-adhesive coating Natural rubber latex concentrate, 100 parts by weight Modified styrene-butadiene copolymer 7.5 parts by weight Amorphous silica 1 part by weight

[0035] <Comparative Example 6> A self-adhesive tape of Comparative Example 5 of the present invention was prepared in the same manner as in Example 1, except that the coating for the self-adhesive layer was changed to the one described below. Self-adhesive coating Natural rubber latex concentrate, 100 parts by weight Modified styrene-butadiene copolymer 7.5 parts by weight Amorphous silica 10 parts by weight

[0036] 2. Evaluation Method The self-adhesive tapes of the examples and comparative examples prepared as described above were evaluated according to the following method: adhesive strength between self-adhesive layers, adhesion, pencil writing properties on the opposite side of the self-adhesive layer, water resistance, and adhesive strength between the self-adhesive layer and its opposite side. The results of these evaluations are shown in Table 1.

[0037] <Adhesion between self-adhering layers> The self-adhesive layers were stacked facing each other, and then compressed by passing a 350g load roll back and forth once. The adhesive strength (N / 6mm) was measured by T-shaped peeling using a tensile testing machine (product name: Tensilon RTG-1210, manufactured by A&D Co., Ltd.) at a tensile speed of 300mm / min.

[0038] <Adhesion> The self-adhesive tape was cut to a width of 15 mm and a length of 200 mm. The tip of the self-adhesive tape was folded inward by about 10 mm along its length, and the adhesive layer was overlapped with the tape. The center of a cylinder with a diameter of 15 mm, a length of 150 mm, and a weight of about 20 g was wrapped with the self-adhesive tape, and the adhesive layers at both ends of the tape were overlapped. The cylinder was rotated three times in the direction in which the adhesive layers were overlapped, and then the cylinder was rotated back in the opposite direction. The state was checked when the tape was quickly peeled off by grasping both ends with hands. ○: As shown in Figure 2(A), peeling occurs at the interface between the self-adhesive layers. ×: As shown in Figure 2(B), the self-adhesive layer adheres to the cylinder, or the self-adhesive layer is taken by the self-adhesive layer of the other object.

[0039] <Pencil writability on the opposite side of the self-adhering layer> The ability to write by hand on the opposite side of the self-adhering layer was confirmed. A Uni 0.5-201HB mechanical pencil lead (manufactured by Mitsubishi Pencil) was used for writing. ○: The writing area is clearly identifiable. ×: Writing is practically impossible

[0040] <water resistance> After soaking the self-adhesive tape in water for one hour, we checked whether the tape would break when gently pulled with both hands. ○: No cutting ×: A cut is made. Or it is completely cut.

[0041] <Adhesion strength between the self-adhesive layer and the opposite surface> The self-adhesive layer and its opposite side (substrate) are laminated facing each other, at 500 g / cm². 2 The samples were pressed together under pressure and left in a 50°C environment for 96 hours. Then, the adhesive strength (N / 15mm) was measured by T-shaped peeling using a tensile testing machine (product name: Tensilon RTG-1210, manufactured by A&D Co., Ltd.) at a tensile speed of 300 mm / min.

[0042] [Table 1]

[0043] As shown in Table 1, in Examples 1 to 3, the self-adhesion force between the self-adhesive layers 3 was 1.2 N / 6 mm or more, and the adhesive force between the self-adhesive layer and its opposite surface (substrate) was 0.4 N / 15 mm or less, resulting in high self-adhesion while still being easily unrolled. Furthermore, in Examples 1 to 3, satisfactory results were obtained in terms of adhesion, writability, and water resistance.

[0044] In contrast, in Comparative Example 1, because the anchoring agent was a chlorinated polyolefin, the adhesion between the anchoring agent layer and the self-adhesive layer was weak, and as a result, the self-adhesive layer adhered to the cylinder, as shown in Figure 2(B).

[0045] In Comparative Example 2, because there was no anchoring layer, the adhesive strength between the substrate and the self-adhesive layer was weak, and as a result, the self-adhesive layer adhered to the cylinder, as shown in Figure 2. Furthermore, in Comparative Example 2, the adhesive strength between the self-adhesive layer and the opposite surface exceeded 0.4 N / 15 mm, making it difficult to unroll.

[0046] In Comparative Example 3, writing was not possible because the substrate was PET resin.

[0047] In Comparative Example 4, the self-adhesive tape broke because the base material was bleached kraft paper.

[0048] In Comparative Example 5, the filler / binder ratio was 0.009, which was lower than 0.044, indicating a higher binder ratio. As a result, the adhesive strength between the self-adhesive layer and the opposite surface exceeded 0.40 N / 15 mm, making it difficult to unravel.

[0049] In Comparative Example 6, the filler / binder ratio was 0.093, which was higher than the filler ratio of 0.066. As a result, the adhesive strength between the self-adhesive layer and the opposite surface was significantly lower than 0.40 N / 15 mm, and consequently, the self-adhesive strength was lower than 1.2 N / 6 mm. [Industrial applicability]

[0050] This invention can be used in the field of self-adhesive tapes used for bundling fruits and vegetables, fresh flowers, and other items, as well as for tagging items with information about them. [Explanation of Symbols]

[0051] 1...Base material, 2...Anchor layer, 3...Self-adhesive layer.

Claims

1. In a self-adhesive tape in which an anchoring agent layer and a self-adhesive agent layer are laminated in that order on one side of the base material, The aforementioned substrate is a synthetic paper having fine pores, The anchoring agent in the aforementioned anchoring agent layer is a mixture of polyolefin resin and polyether urethane in a weight ratio of 75 / 25 to 80 / 20. The self-adhesive layer consists of a natural rubber latex concentrate as the main component, a modified styrene-butadiene copolymer as the binder, and amorphous silica as the filler, with a weight ratio of filler to main component and binder of 0.044 to 0.

066. A self-adhesive tape having a self-adhesive force of 1.2 N / 6 mm or more between the self-adhesive layers, and an adhesive force of 0.4 N / 15 mm or less between the self-adhesive layer and the substrate.

2. The self-adhesive tape according to claim 1, wherein the self-adhesive agent contains 5 to 10 parts by weight of a modified styrene-butadiene copolymer per 100 parts by weight of a natural rubber latex stock solution.

3. The self-adhesive tape according to claim 1 or 2, wherein the base material is synthetic paper having a large number of fine pores and made primarily from polypropylene resin.

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