Adhesive sheet, method for manufacturing adhesive sheet, and printed matter

Abstract

To provide an adhesive sheet excellent in weather resistance and printability due to an inkjet method, a manufacturing method of an adhesive sheet capable of suitably manufacturing the adhesive sheet, and a printed matter excellent in weather resistance and having a printed portion less in bleeding and excellent in printing quality.SOLUTION: An adhesive sheet of the present invention is an adhesive sheet that is used for printing by an inkjet method, and has a base material and an adhesive layer provided in contact with the base material, and the base material is composed of a material containing polyvinyl chloride and a leveling agent. The leveling agent is preferably at least one selected from the group consisting of silicone leveling agents, acrylic leveling agents and fluorine leveling agents.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a pressure-sensitive adhesive sheet, a method for producing a pressure-sensitive adhesive sheet, and a printed matter. [Background technology]

[0002] BACKGROUND ART Polyvinyl chloride sheets have been widely used as decorative pressure-sensitive adhesive sheets for advertisements, signs, and the like because of their excellent weather resistance and ability to conform to curved or uneven surfaces.

[0003] In applications such as advertising and signboards, replacement is often required at relatively short intervals, and small-lot production is often required.

[0004] On the other hand, printing by the inkjet method has the characteristics of being excellent in on-demand printing and being suitable for producing a large number of printed items in small quantities.

[0005] The inkjet method is also increasingly being applied to printing on decorative adhesive sheets.

[0006] However, when printing is performed on conventional polyvinyl chloride by the inkjet method, there is a problem that the print by the inkjet method tends to become unclear due to bleeding.

[0007] In order to solve the above-mentioned problems that occur when printing by the inkjet method, a sheet material provided with an ink-receiving layer made of a predetermined material has been proposed (see, for example, Patent Document 1).

[0008] However, even such sheet materials have not been able to provide sufficiently excellent printability by the ink-jet method. Furthermore, as mentioned above, decorative adhesive sheets for advertisements, signs, etc., are required to be able to conform to curved or uneven surfaces, and therefore the substrate needs to be flexible and extensible. The sheet material of Patent Document 1 had insufficient flexibility and extensibility. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Patent No. 3745993 Summary of the Invention [Problem to be solved by the invention]

[0010] The object of the present invention is to provide an adhesive sheet that has excellent weather resistance and other properties and is excellent in suitability for printing by the inkjet method, to provide a method for manufacturing an adhesive sheet that can suitably manufacture the adhesive sheet, and to provide a printed matter that has excellent weather resistance and other properties and has a printed part with excellent printing quality that causes little bleeding by the inkjet method. [Means for solving the problem]

[0011] Such objectives are as follows: (1) 7 This is achieved by the present invention described in (1) An adhesive sheet used for printing by the inkjet method, A substrate and a pressure-sensitive adhesive layer provided in contact with the substrate, The substrate is made of polyvinyl chloride , plasticizer and a material containing a leveling agent. And, The average degree of polymerization of the polyvinyl chloride is 1000 or more and 2000 or less, the content of the plasticizer in the base material is 25 parts by mass or more and 40 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride, the content of the leveling agent in the base material is 0.5 parts by mass or more and 20.0 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride; The thickness of the substrate is 5 μm or more and 200 μm or less. A pressure-sensitive adhesive sheet characterized by:

[0012] (2) The pressure-sensitive adhesive sheet according to (1) above, wherein the leveling agent is at least one selected from the group consisting of silicone-based leveling agents, acrylic-based leveling agents, and fluorine-based leveling agents.

[0013] (3) The pressure-sensitive adhesive sheet according to (1) or (2) above, wherein the substrate is formed by applying a liquid composition containing the polyvinyl chloride and the leveling agent to the surface of a support that has not been subjected to a release treatment, followed by drying.

[0014] (4) The pressure-sensitive adhesive sheet according to any one of (1) to (3) above, wherein the surface of the pressure-sensitive adhesive layer opposite to the surface that comes into contact with the substrate is covered with a release liner.

[0018] ( 5 ) Polyvinyl chloride , plasticizer and a coating step of coating a liquid composition containing the leveling agent on a support that has not been subjected to a release treatment; a solidification step of solidifying the composition coated on the support to form a substrate; and forming a pressure-sensitive adhesive layer on the surface of the base material formed on the support. death, The average degree of polymerization of the polyvinyl chloride is 1000 or more and 2000 or less, the content of the plasticizer in the base material is 25 parts by mass or more and 40 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride, the content of the leveling agent in the base material is 0.5 parts by mass or more and 20.0 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride; The thickness of the substrate is 5 μm or more and 200 μm or less. A method for producing a pressure-sensitive adhesive sheet, comprising:

[0019] ( 6 The composition further contains an organic solvent in addition to the polyvinyl chloride and the leveling agent. 5 ) A method for producing a pressure-sensitive adhesive sheet according to the above.

[0020] ( 7 ) (1) above or ( 4 10. A printed matter comprising a printed portion formed by an inkjet method on the substrate of the pressure-sensitive adhesive sheet according to any one of claims 1 to 9. [Effects of the Invention]

[0021] According to the present invention, it is possible to provide an adhesive sheet that has excellent weather resistance and other properties and is excellent in suitability for printing by the inkjet method, to provide a method for manufacturing an adhesive sheet that can suitably manufacture the adhesive sheet, and to provide a printed matter that has excellent weather resistance and other properties and has a printed part with excellent printing quality that causes little bleeding by the inkjet method. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a schematic longitudinal sectional view showing a preferred embodiment of the pressure-sensitive adhesive sheet of the present invention. [Figure 2] 1 is a schematic longitudinal sectional view showing a preferred embodiment of the method for producing a pressure-sensitive adhesive sheet of the present invention. [Figure 3] 1 is a schematic longitudinal sectional view showing a preferred embodiment of a printed matter of the present invention. [Figure 4] FIG. 1 is a schematic longitudinal cross-sectional view showing an example of a state in which a printed matter of the present invention is covered with a laminate sheet. DETAILED DESCRIPTION OF THE INVENTION

[0023] Preferred embodiments of the present invention will be described in detail below. [1] Adhesive sheet First, the pressure-sensitive adhesive sheet of the present invention will be described.

[0024] FIG. 1 is a schematic longitudinal sectional view showing a preferred embodiment of the pressure-sensitive adhesive sheet of the present invention. The adhesive sheet 10 is used for printing by the inkjet method and includes a substrate 11 and an adhesive layer 12 provided in contact with the substrate 11. The substrate 11 is made of a material containing polyvinyl chloride and a leveling agent.

[0025] This makes it possible to provide a pressure-sensitive adhesive sheet 10 that is excellent in weather resistance and printability by an inkjet method. Furthermore, the adhesion between the substrate 11 and the pressure-sensitive adhesive layer 12 can be particularly excellent. Furthermore, properties such as film-forming ability and flexibility can also be excellent. Furthermore, as will be described in detail later, during the production of the pressure-sensitive adhesive sheet 10, the substrate 11 formed on the support 300 can be suitably peeled off, and unintended roughening of the surface of the substrate 11 (the surface that was in contact with the support 300) and unintended stretching of the substrate 11 can be effectively prevented, thereby making it possible to provide the pressure-sensitive adhesive sheet 10 with excellent reliability and yield.

[0026] On the other hand, if the above-mentioned configuration is not satisfied, such excellent effects cannot be obtained.

[0027] For example, if the substrate is made of a material that does not contain polyvinyl chloride, it becomes difficult to achieve sufficiently excellent weather resistance, conformability to curved or uneven surfaces, film-forming properties, flexibility, etc. for the entire pressure-sensitive adhesive sheet.

[0028] Furthermore, if the substrate is made of a material that does not contain a leveling agent, it becomes difficult to achieve sufficiently excellent printability by the inkjet method. More specifically, when applied to inkjet printing, the ink spreads too much, causing the image to bleed, making it difficult to form a clear image. Furthermore, when manufacturing a pressure-sensitive adhesive sheet, if the substrate is formed by applying a liquid composition to a support and drying it, it becomes difficult to properly peel the formed substrate from the support, which tends to cause undesired roughness on the surface of the substrate (the surface that was in contact with the support) or undesired stretching of the substrate. Furthermore, the yield of the pressure-sensitive adhesive sheet also decreases significantly.

[0029] [1-1] Base material The substrate 11 is made of a material containing polyvinyl chloride and a leveling agent, and is the portion to be printed by the inkjet method.

[0030] [1-1-1] Polyvinyl chloride Polyvinyl chloride has excellent weather resistance. When used in combination with a plasticizer, which will be described later, it has the characteristics of being excellent in flexibility and shape conformability.

[0031] Polyvinyl chloride is a polymer containing vinyl chloride as a monomer component. Polyvinyl chloride may contain other monomer components in addition to vinyl chloride, but the content of monomer components other than vinyl chloride in polyvinyl chloride is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 0% by mass. This makes the above-mentioned effects more pronounced.

[0032] The average degree of polymerization of the polyvinyl chloride contained in the substrate 11 is preferably 500 or more and 5,000 or less, more preferably 700 or more and 3,000 or less, and even more preferably 1,000 or more and 2,000 or less.

[0033] This can improve the weather resistance, flexibility, shape conformability, etc. of the entire pressure-sensitive adhesive sheet 10. In addition, the affinity and compatibility between polyvinyl chloride and the leveling agent can be improved, and the effects obtained by having polyvinyl chloride and a leveling agent coexist as described above can be more significantly exhibited.

[0034] The average degree of polymerization can be measured, for example, by a method in accordance with JIS K 6720-2:1999. The content of polyvinyl chloride in the substrate 11 is preferably 50% by mass or more.

[0035] [1-1-2] Leveling agent The leveling agent primarily functions to improve the printability of the pressure-sensitive adhesive sheet 10 by an inkjet method. Furthermore, when the pressure-sensitive adhesive sheet 10 is manufactured by a method described in detail below, the leveling agent also functions to improve the ease of peeling the substrate 11 from the support 300. This effectively prevents undesired roughness on the surface of the substrate 11 (the surface that was in contact with the support 300) and undesired stretching of the substrate 11, thereby improving the reliability and yield of the pressure-sensitive adhesive sheet 10. This effect can be achieved even when a support 300 that has not been subjected to a release treatment is used. By using a support 300 that has not been subjected to a release treatment in this way, it is possible to prevent problems such as the release agent transferring to the substrate 11 that has been in contact with the support 300.

[0036] Examples of leveling agents include silicone-based leveling agents, acrylic-based leveling agents, fluorine-based leveling agents, vinyl-based leveling agents, and acetylene glycol-based leveling agents. It is preferable to use at least one selected from the group consisting of silicone-based leveling agents, acrylic-based leveling agents, and fluorine-based leveling agents. This makes the above-mentioned effects more pronounced.

[0037] Examples of silicone leveling agents include BYK-300, BYK-302, BYK-306, BYK-310, BYK-315, BYK-320, BYK-322, BYK-323, BYK-325, BYK-330, BYK-331, BYK-333, BYK-337, BYK-344, BYK-370, BYK-375, BYK-377, BYK-UV3500, BYK-UV3510, and BYK-UV3570 (all of which are listed in BIC). Examples of solid contents include those of commercially available products such as 1711, 1751N, 1761, LS-001, and LS-050 (all manufactured by Kusumoto Chemicals, DISPARLON series), Granol 100, Granol 115, Granol 200, Granol 400, Granol 410, Granol 440, Granol 435, Granol 450, Granol 482, Granol B-1484, and Polyflow ATF-2 (all manufactured by TEGO).

[0038] Examples of acrylic leveling agents include BYK-350, BYK-352, BYK-354, BYK-355, BYK-358N, BYK-361N, and BYK-392 (all manufactured by BYK Japan), OX-880EF, OX-881, OX-883, OX-883HF, OX-70, OX-77EF, OX-60, OX-710, OX-720, OX-720EF, OX-750HF, LAP-10, LAP-20, LAP-30, 1970, 230, LF-1980, LF-1982, LF-1983, LF-1984, LF-1985, LHP-95, and LHP-96 (all manufactured by Kusumoto Chemicals Co., Ltd.). Examples of the solid content include the solid content of commercially available products such as Polyflow No. 3, Polyflow No. 7, Polyflow No. 50E, Polyflow No. 50EHF, Polyflow No. 54N, Polyflow No. 55, Polyflow No. 64, Polyflow No. 75, Polyflow No. 77, Polyflow No. 85, Polyflow No. 85HF, Polyflow No. S, Polyflow No. 90, Polyflow No. 90D-50, Polyflow No. 95, Polyflow No. 300, Polyflow No. 460, Polyflow WS, Polyflow WS-30, and Polyflow WS-314 (all manufactured by Kyoeisha Chemical Co., Ltd.).

[0039] Examples of fluorine-based leveling agents include the solid content of commercially available fluorine-modified polymers such as BYK-340 and BYK-3441 (all manufactured by BYK Japan), S-242, S-243, S-420, and S-431 (all manufactured by AGC Seimi Chemical Co., Ltd.).

[0040] Examples of vinyl leveling agents include the solid content of commercially available products such as LHP-90 and LHP-91 (both manufactured by Kusumoto Chemicals Co., Ltd., DISPARLON series).

[0041] The content of the leveling agent in the substrate 11 relative to 100 parts by mass of polyvinyl chloride is preferably 0.5 parts by mass or more and 20.0 parts by mass or less, more preferably 1.0 parts by mass or more and 18.0 parts by mass or less, and even more preferably 2.5 parts by mass or more and 15.0 parts by mass or less.

[0042] This not only makes the above-mentioned effects more pronounced, but also more effectively prevents ink from being repelled when printing is performed by the inkjet method. In this way, ink bleeding and repelling are prevented to a higher degree, resulting in better quality printing by the inkjet method.

[0043] [1-1-3] Plasticizers The substrate 11 contains a plasticizer in addition to the polyvinyl chloride and leveling agent described above. A plasticizer is usually used to impart flexibility.

[0044] Examples of the plasticizer include phthalate ester-based plasticizers such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, di-n-octyl phthalate, and dicyclohexyl phthalate; trimellitate ester-based plasticizers such as trioctyl trimellitate, triisononyl trimellitate, and triisodecyl trimellitate; adipic acid-based plasticizers such as dioctyl adipate, diisononyl adipate, and diisodecyl adipate; polyester-based plasticizers such as phthalic acid-based polyesters; phosphate ester-based plasticizers such as tricresyl phosphate, trioctyl phosphate, and triphenyl phosphate; and epoxy-based plasticizers such as epoxidized linseed oil and epoxidized butyl stearate.

[0045] The weight average molecular weight of the polyester plasticizer is preferably 2,000 or more and 6,000 or less.

[0046] The content of the plasticizer is preferably 25 parts by mass or more and 40 parts by mass or less, and more preferably 27 parts by mass or more and 35 parts by mass or less, relative to 100 parts by mass of polyvinyl chloride.

[0047] [1-1-4] Colorants The substrate 11 may contain a colorant.

[0048] As the colorant, for example, various pigments and various dyes can be used, but from the viewpoint of light resistance and the like, pigments are preferred.

[0049] When the substrate 11 is white, for example, titanium oxide can be suitably used as the colorant (pigment).

[0050] [1-1-5] Other ingredients The substrate 11 may contain components other than those described above. Examples of such components include resin materials other than polyvinyl chloride, cellulose, cellulose derivatives, various fillers, dispersants, ultraviolet absorbers, antistatic agents, antioxidants, pH adjusters, preservatives, rust inhibitors, deodorizers, antibacterial agents, antifungal agents, antiviral agents, disinfectants, crosslinking agents, polymerization initiators, fixing agents, and flocculants.

[0051] However, the content of components other than polyvinyl chloride, leveling agent, plasticizer, and colorant in the base material 11 is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less, per 100 parts by mass of polyvinyl chloride.

[0052] [1-1-6] Other conditions of the substrate The substrate 11 may have a substantially uniform composition throughout, or may have portions with different compositions, as long as the entire substrate has sufficient flexibility and curve-conforming ability. For example, the substrate 11 may be made of a gradient material whose composition changes gradually in the thickness direction, or may be a laminate having multiple layers. Furthermore, different portions within the plane of the substrate 11 may have different compositions.

[0053] The thickness of the substrate 11 is preferably 5 μm or more and 200 μm or less, and more preferably 20 μm or more and 100 μm or less.

[0054] This allows the adhesive sheet 10 to achieve both flexibility and durability at a higher level. It also makes the adhesive sheet 10 easier to handle when adhering to an adherend. Furthermore, when the adhesive sheet 10 is manufactured by a method described in detail below, the substrate 11 can be more suitably peeled from the support 300.

[0055] The substrate 11 may be formed by any method, but can be suitably formed, for example, by a casting method using a liquid composition containing the above-mentioned components. Forming the substrate by a casting method can prevent undesired thermal shrinkage after application.

[0056] In particular, it is preferable that the substrate 11 is formed by applying a liquid composition containing polyvinyl chloride and a leveling agent to the surface of a support 300 that has not been subjected to a release treatment, drying the composition, and then peeling off the support 300.

[0057] This prevents the release agent from transferring to the substrate 11 that has been in contact with the support 300, and more effectively prevents ink from being repelled when forming the printed portion 30 by an inkjet method, thereby improving the print quality of the printed portion 30.

[0058] The method for forming the substrate 11 and the method for manufacturing the adhesive sheet 10 will be described in detail later.

[0059] [1-2] Adhesive layer The adhesive layer 12 is made of a material containing an adhesive, and is the part that comes into contact with the adherend when the sheet is stuck to the adherend.

[0060] [1-2-1] Adhesive The adhesive constituting the adhesive layer 12 is not particularly limited, and examples thereof include acrylic adhesives, rubber adhesives, silicone adhesives, polyurethane adhesives, and polyester adhesives.

[0061] Among these, acrylic pressure-sensitive adhesives are preferred. Acrylic pressure-sensitive adhesives are generally prepared by crosslinking a copolymer of a (meth)acrylic acid alkyl ester monomer, which provides adhesiveness, and a monomer containing a functional group with a crosslinking agent.

[0062] Examples of the (meth)acrylic acid alkyl ester monomer that provides adhesiveness include butyl acrylate and 2-ethylhexyl acrylate.

[0063] Examples of the monomer containing a functional group include 2-hydroxyethyl (meth)acrylate and (meth)acrylic acid.

[0064] Examples of the crosslinking agent include an isocyanate compound, an epoxy compound, and a metal chelate compound.

[0065] [1-2-2] Other ingredients The pressure-sensitive adhesive layer 12 may contain components other than the above-mentioned pressure-sensitive adhesives, such as tackifiers, plasticizers, colorants such as pigments and dyes, various fillers, surfactants, dispersants, UV absorbers, antistatic agents, leveling agents, antioxidants, pH adjusters, preservatives, antirust agents, deodorizers, antibacterial agents, antifungal agents, antiviral agents, disinfectants, crosslinking agents, and polymerization initiators.

[0066] Examples of tackifiers that can be used include rosin-based resins such as rosin, rosin phenolic resins, and their ester compounds, hydrogenated rosin esters, terpene resins such as terpene oligomers, terpene phenolic resins, and aromatic-modified terpene resins, C5 petroleum resins, and C9 petroleum resins. More preferably, hydrogenated rosin esters and / or aromatic-modified terpene resins can be used.

[0067] However, the content of components other than the adhesive in the adhesive layer 12 is preferably 15% by mass or less.

[0068] [1-2-3] Other conditions for the adhesive layer The pressure-sensitive adhesive layer 12 may have a substantially uniform composition throughout, or may have portions with different compositions. For example, the pressure-sensitive adhesive layer 12 may be made of a gradient material whose composition changes gradually in the thickness direction, or may be a laminate having multiple layers. Furthermore, different portions within the plane of the pressure-sensitive adhesive layer 12 may have different compositions.

[0069] The thickness of the pressure-sensitive adhesive layer 12 is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or more and 60 μm or less.

[0070] [1-3] Overall structure of adhesive sheet The thickness of the adhesive sheet 10 is preferably 10 μm or more and 300 μm or less, and more preferably 40 μm or more and 160 μm or less.

[0071] This allows for a higher level of both flexibility and durability of the pressure-sensitive adhesive sheet 10. Furthermore, the pressure-sensitive adhesive sheet 10 can be made easier to handle when adhering to an adherend.

[0072] [1-4] Release liner The surface of the adhesive layer 12 of an unused adhesive sheet 10, i.e., the surface of the adhesive layer 12 opposite to the surface that contacts the substrate 11, is preferably covered with a release liner 20, as shown in FIG. 1.

[0073] This makes it easier to handle unused pressure-sensitive adhesive sheet 10 and also provides suitable protection for pressure-sensitive adhesive layer 12 before it is attached to an adherend.

[0074] The release liner 20 may be, for example, a sheet made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene, polyarylate, etc., or a base material made of various paper materials such as polyethylene-laminated paper, polypropylene-laminated paper, clay-coated paper, resin-coated paper, glassine paper, or high-quality paper, with a release treatment applied, if necessary, to the surface of the base material that comes into contact with the adhesive layer 12.

[0075] Examples of the release treatment include forming a release agent layer made of a release agent such as a silicone resin, a long-chain alkyl resin, or a fluorine-based resin.

[0076] [2] Manufacturing method of adhesive sheet Next, a method for producing the pressure-sensitive adhesive sheet of the present invention will be described.

[0077] FIG. 2 is a schematic longitudinal sectional view showing a preferred embodiment of the method for producing a pressure-sensitive adhesive sheet of the present invention.

[0078] The manufacturing method of the embodiment shown in FIG. 2 includes a coating step (1a) of coating a liquid composition containing polyvinyl chloride and a leveling agent onto a support 300 that has not been subjected to a release treatment, a solidification step (1b) of solidifying the composition coated on the support 300 to form a substrate 11, and an adhesive layer formation step (1c) of forming an adhesive layer 12 on the surface of the substrate 11 formed on the support 300.

[0079] This makes it possible to provide a method for manufacturing a pressure-sensitive adhesive sheet 10 that can suitably manufacture a pressure-sensitive adhesive sheet 10 that has excellent weather resistance and excellent printability by an inkjet method. Furthermore, the adhesion between the substrate 11 and the pressure-sensitive adhesive layer 12 can be made particularly excellent. Furthermore, properties such as film-forming ability and flexibility can also be made excellent. Furthermore, the substrate 11 formed on the support 300 can be suitably peeled off, and unintended roughening of the surface of the substrate 11 (the surface that was in contact with the support 300) and unintended stretching of the substrate 11 can be effectively prevented, thereby making it possible to improve the reliability and yield of the pressure-sensitive adhesive sheet 10.

[0080] [2-1] Coating process In the coating step, a liquid composition 11' containing polyvinyl chloride and a leveling agent is coated onto a support 300 that has not been subjected to a release treatment (see (1a) in FIG. 2).

[0081] The composition 11' may contain at least polyvinyl chloride and a leveling agent, but preferably further contains a plasticizer and an organic solvent in addition to these.

[0082] This allows composition 11' to have more suitable fluidity and the coating process to be carried out more efficiently. In particular, in the coating process, sufficient fluidity can be ensured without excessive heating of composition 11', and unintended denaturation, deterioration, etc. of the components of composition 11' can be more effectively prevented, resulting in more reliable PSA sheet 10 that is produced, which is also preferred from the standpoint of energy conservation, etc.

[0083] Examples of organic solvents that can be used in the composition 11' include methyl isobutyl ketone, methyl ethyl ketone, butyl acetate, ethylene glycol monobutyl ether, tetrahydrofuran, benzene, toluene, xylene, paraffinic hydrocarbons, and naphthenic hydrocarbons. One or more of these can be used in combination. Commercially available mixed solvents made from petroleum fractions can also be used.

[0084] When composition 11' contains an organic solvent, the content of the organic solvent in composition 11' is not particularly limited, but is preferably 10% by mass or more and 90% by mass or less, more preferably 15% by mass or more and 85% by mass or less, and even more preferably 20% by mass or more and 80% by mass or less.

[0085] Any material may be used as the support 300, but a film made of a resin material such as polyethylene terephthalate is preferably used.

[0086] In particular, it is preferable that the support 300 is not subjected to a release treatment using a release agent.

[0087] This prevents the occurrence of problems such as uneven transfer of the release agent to the substrate 11 that has been in contact with the support 300, and more effectively prevents ink from being repelled when forming the printed portion 30 by an inkjet method on the manufactured pressure-sensitive adhesive sheet 10. As a result, the printing quality of the printed portion 30 can be improved.

[0088] [2-2] Solidification process In the solidification step, the composition 11' applied onto the support 300 is solidified to form the substrate 11 (see (1b) in FIG. 2).

[0089] When composition 11' contains an organic solvent, this step can be carried out by, for example, volatilizing the organic solvent from composition 11' coated on support 300 by heating, reducing pressure, or the like, and then heating and melting vinyl chloride to gel it. The heating and melting temperature is preferably 170°C or higher and 220°C or lower, and more preferably 180°C or higher and 200°C or lower.

[0090] Furthermore, when the composition 11' does not contain an organic solvent and the coating step is carried out in a molten state of the composition 11', this step (solidification step) can be carried out by cooling.

[0091] [2-3] Adhesive layer formation process In the adhesive layer forming step, an adhesive layer 12 is formed on the surface of a substrate 11 formed on a support 300 (see (1c) in FIG. 2).

[0092] The adhesive layer 12 may be formed, for example, by applying a liquid adhesive composition to the surface of the substrate 11 (the surface opposite to the surface in contact with the support 300) and drying the dilution solvent, or by applying a liquid adhesive composition onto a release liner 20 and drying the dilution solvent, and then transferring the composition to the surface of the substrate 11 (the surface opposite to the surface in contact with the support 300).

[0093] By this step, adhesive sheet 10, which is a laminate of substrate 11 and adhesive layer 12, is formed on support 300.

[0094] [2-4] Peeling process This embodiment further includes a peeling step of peeling the formed laminate of the substrate 11, the pressure-sensitive adhesive layer 12, and the release liner 20 from the support 300 (see (1d) in FIG. 2). This peeling step may be performed at any time after the pressure-sensitive adhesive layer forming step and before printing.

[0095] This results in a laminate in which adhesive layer 12 of adhesive sheet 10, which is a laminate of substrate 11 and adhesive layer 12, is protected by release liner 20.

[0096] In this way, by peeling the adhesive layer 12 of the adhesive sheet 10 from the support 300 while it is protected by the release liner 20, it is possible to effectively prevent the adhesive layer 12 from being unintentionally soiled or the adhesive sheet 10 from adhering to unintended locations during the peeling process or subsequent processing.

[0097] [3] Printed matter Next, the printed matter of the present invention will be described.

[0098] Fig. 3 is a schematic vertical cross-sectional view showing a preferred embodiment of the printed matter of the present invention. Fig. 4 is a schematic vertical cross-sectional view showing an example of the printed matter of the present invention covered with a laminate sheet.

[0099] The printed matter 100 is characterized in that a printed portion 30 is formed on a substrate 11 of an adhesive sheet 10 by an inkjet method.

[0100] This makes it possible to provide a printed matter having excellent weather resistance and other properties, as well as having a printed portion of excellent print quality with little bleeding due to the inkjet method.

[0101] The ink used to form the printed portion 30 is not particularly limited, and examples thereof include oil-based ink (solvent-based ink), water-based ink, latex ink, photocurable ink (ultraviolet-curable ink, electron beam-curable ink), etc. Among these, oil-based ink (solvent-based ink) is more preferable.

[0102] Conventionally, when such inks are used to form printed portions by inkjet printing, the problems described above are particularly likely to occur, but according to the present invention, the occurrence of the problems described above can be effectively prevented even when such inks are used. In other words, when the inks described above are used to form printed portion 30, the effects of the present invention are more pronounced.

[0103] Furthermore, the printed portion 30 may be formed using a combination of two or more types of ink. In the illustrated configuration, the printed portion 30 is provided on the entire surface of the substrate 11, but the printed portion 30 may be provided on only a part of the surface of the substrate 11.

[0104] The printed portion 30 may be formed before the adhesive sheet 10 is stuck to the adherend, or may be formed after the adhesive sheet 10 is stuck to the adherend. The content displayed by the printing unit 30 is not particularly limited.

[0105] The printed matter 100 may be used as is by adhering it to an adherend, or, for example, as shown in Figure 4, it may be used with the surface on which the printed portion 30 is provided covered with a laminate sheet 200.

[0106] The configuration of the laminate sheet 200 is not particularly limited, but in the configuration shown in the figure, it has a laminate sheet substrate 50 and an adhesive layer 60 .

[0107] The laminate sheet substrate 50 may be made of any material, but is usually made primarily of a resin material.

[0108] Examples of resin materials that can be used to form the laminate sheet substrate 50 include polyvinyl chloride, acrylic resins, and fluorine-based resins.

[0109] The thickness of the laminate sheet substrate 50 is preferably 10 μm or more and 100 μm or less, and more preferably 20 μm or more and 80 μm or less.

[0110] The adhesive layer 60 is made of a material containing an adhesive, and is the portion that comes into contact with the surface of the printed matter 100 on which the printed portion 30 is provided.

[0111] The adhesive that constitutes the adhesive layer 60 is not particularly limited, and examples thereof include acrylic adhesives, rubber adhesives, silicone adhesives, polyurethane adhesives, and polyester adhesives.

[0112] The thickness of the adhesive layer 60 is preferably 5 μm or more and 100 μm or less, and more preferably 10 μm or more and 60 μm or less.

[0113] When the printed matter 100 is covered with the laminate sheet 200, the covering of the laminate sheet 200 onto the printed matter 100 may be performed before the printed matter 100 is attached to the substrate, or may be performed after the printed matter 100 is attached to the substrate.

[0114] The printed matter of the present invention can be used for various public relations, advertisements, signboards, etc. These include, for example, wrapping of vehicle bodies, attachment to wall surfaces, etc.

[0115] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these.

[0116] For example, in the illustrated configuration, the printed portion is provided on the substrate, but a portion of the printed portion may penetrate into the substrate.

[0117] In the above-described embodiment, a peeling step of peeling the substrate from the support is performed after forming a pressure-sensitive adhesive layer on the surface of the substrate, but the peeling step may be performed before forming a pressure-sensitive adhesive layer on the surface of the substrate, and a pressure-sensitive adhesive layer may be formed on the substrate peeled from the support. In this case, it is preferable that the pressure-sensitive adhesive layer is provided on the surface of the substrate opposite to the surface that was in contact with the support.

[0118] Furthermore, in the above-described embodiment, the case where a substrate is manufactured using a support that has not been subjected to a release treatment has been mainly described, but a support that has been subjected to a release treatment may also be used to manufacture the substrate. [Example]

[0119] The present invention will be described in detail below based on specific examples, but the present invention is not limited thereto. In the following examples, treatments and measurements for which no temperature conditions are specified were carried out at 25°C.

[0120] [4] Manufacturing of adhesive sheets Example 1 A liquid composition was obtained by dispersing 100 parts by weight of polyvinyl chloride (Tosoh Corporation, Ryuron Paste 860) with an average degree of polymerization of 1600, 30 parts by weight of an adipic acid-based polyester plasticizer (ADEKA Corporation, P-200), and 2.5 parts by weight of an acrylic copolymer leveling agent (BYK Japan, BYK-392) (all solids ratios) in ethylene glycol monobutyl ether as an organic solvent. The organic solvent content in the resulting composition was 30% by weight.

[0121] The composition thus obtained was applied to a support made of polyethylene terephthalate film (not subjected to a release treatment) by a casting method and dried to prepare a substrate having a thickness of 50 μm.

[0122] On the other hand, the pressure-sensitive adhesive composition was coated onto the release agent-treated surface of the release liner using a roll knife coater so that the coating thickness after drying would be 25 μm, and dried at 90° C. for 1 minute. An acrylic adhesive was used as the adhesive composition.

[0123] Next, this dried adhesive composition (adhesive layer) was brought into contact with the substrate produced as described above, and then the support was peeled off and removed to obtain an adhesive sheet in which the adhesive layer was protected by a release liner.

[0124] Example 2 An adhesive sheet was produced in the same manner as in Example 1, except that a polyether-modified polymethylalkylsiloxane leveling agent (BYK-320, manufactured by BYK Japan) was used instead of the acrylic copolymer leveling agent.

[0125] Example 3 Instead of acrylic copolymer leveling agents, C6F 13A pressure-sensitive adhesive sheet was produced in the same manner as in Example 1, except that a fluorotelomer-containing acrylic copolymer leveling agent (BYK-3441, manufactured by BYK Japan) was used.

[0126] Examples 4 to 9 A pressure-sensitive adhesive sheet was produced in the same manner as in Example 1 above, except that the type and amount of leveling agent used were changed so that the base material had the structure shown in Table 1.

[0127] (Comparative Example 1) The adhesive sheet was manufactured in the same manner as in Example 1, except that the composition used to form the substrate did not contain a leveling agent; more specifically, a composition obtained by dispersing 100 parts by mass of polyvinyl chloride (Tosoh Corporation, Ryuron Paste 860) with an average degree of polymerization of 1600 and 30 parts by mass of adipic acid-based polyester plasticizer (ADEKA Corporation, P-200) (all solids ratios) in ethylene glycol monobutyl ether as an organic solvent was used.

[0128] (Comparative Example 2) A pressure-sensitive adhesive sheet was produced in the same manner as in Comparative Example 1, except that a polyethylene terephthalate film that had been subjected to a release treatment with silicone was used as the support.

[0129] The configurations of the pressure-sensitive adhesive sheets of the examples and comparative examples are summarized in Table 1. In Table 1, the solid content of polyvinyl chloride (Ryuron Paste 860, manufactured by Tosoh Corporation) is designated "PVC1," the solid content of adipic acid polyester plasticizer (P-200, manufactured by ADEKA Corporation) is designated "P1," the solid content of an acrylic copolymer leveling agent (BYK-392, manufactured by BYK Japan) is designated "LA1," the solid content of a polyether-modified polymethylalkylsiloxane leveling agent (BYK-320, manufactured by BYK Japan) is designated "LA2," and the solid content of a CF 13 The solid content of the fluorotelomer-containing acrylic copolymer leveling agent (BYK-3441, manufactured by BYK Japan) is indicated as "LA3."

[0130] [Table 1]

[0131] [5] Production of printed materials A printed portion was formed by printing the identification number N1 (portrait) of a high-definition color digital standard image defined in JIS X 9201:2001 on the substrate side surface of the pressure-sensitive adhesive sheet of each of the Examples and Comparative Examples by an inkjet method using an inkjet printer (JV33-130, manufactured by Mimaki Engineering Co., Ltd.), thereby obtaining a printed matter.

[0132] In this case, the ink used was SS21 ink (manufactured by Mimaki Engineering Co., Ltd.), which is a solvent-based ink (oil-based ink).

[0133] [6] Evaluation The printed matter of each of the examples and comparative examples was evaluated as follows.

[0134] [6-1] Bleeding evaluation The printed surface of each of the examples and comparative examples was visually observed and evaluated according to the following criteria.

[0135] A: A very clear appearance with no bleeding observed. B: The image has a sufficiently clear appearance with almost no bleeding. C: Although slight bleeding is observed, the image appears relatively clear. D: Blurring is clearly observed and clarity is insufficient. E: Significant bleeding is observed, resulting in an unclear appearance.

[0136] [6-2] Playing evaluation The printed surface of each of the examples and comparative examples was visually observed and evaluated according to the following criteria.

[0137] A: A very clear appearance with no ink repellency whatsoever. B: The appearance is sufficiently clear with almost no ink repellency observed. C: A slight ink repellency is observed, but the appearance is relatively clear. D: Ink repellency is clearly observed and clarity is insufficient. E: Ink repellency is evident, and the appearance is unclear.

[0138] [6-3] Weather resistance evaluation The pressure-sensitive adhesive sheets of the above-mentioned Examples and Comparative Examples were attached to an acrylic coated plate and subjected to a 2000-hour accelerated weather resistance test using a sunshine weather meter, and were evaluated according to the following criteria.

[0139] A: No cracks or yellowing are observed. B: Slight cracking or yellowing is observed. C: Cracks and yellowing are clearly observed. These results are summarized in Table 2.

[0140] [Table 2]

[0141] As is clear from Table 2, the pressure-sensitive adhesive sheets of the above Examples achieved excellent results. In contrast, the pressure-sensitive adhesive sheets of the above Comparative Examples did not achieve satisfactory results. In particular, in Comparative Example 1, roughness of the substrate surface occurred when the substrate was peeled from the support, and undesired stretching of the substrate was observed. Furthermore, in Comparative Example 2, in which the support was subjected to a release treatment, significant ink repellency occurred. This is thought to be due to the release agent used in the release treatment of the support migrating to the substrate. Furthermore, pressure-sensitive adhesive sheets were produced in the same manner as in the above Examples and Comparative Examples, except that the average degree of polymerization of polyvinyl chloride was variously changed within the range of 1000 to 2000 and the thickness of the substrate was variously changed within the range of 5 μm to 200 μm. These were then evaluated in the same manner as above, and the same results were obtained. [Explanation of symbols]

[0142] 10...Adhesive sheet 11...Base material 11'...composition 12...Adhesive layer 20...Release liner 30…Printing department 50...Laminate sheet base material 60...Adhesive layer 100…Printed material 200...Laminate sheet 300...Support

Claims

1. An adhesive sheet used for printing by an inkjet method, A substrate and a pressure-sensitive adhesive layer provided in contact with the substrate, the substrate is made of a material containing polyvinyl chloride, a plasticizer, and a leveling agent; The average degree of polymerization of the polyvinyl chloride is 1000 or more and 2000 or less, the content of the plasticizer in the base material is 25 parts by mass or more and 40 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride, the content of the leveling agent in the base material is 0.5 parts by mass or more and 20.0 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride, A pressure-sensitive adhesive sheet characterized in that the thickness of the substrate is 5 μm or more and 200 μm or less.

2. 2. The pressure-sensitive adhesive sheet according to claim 1, wherein the leveling agent is at least one selected from the group consisting of a silicone-based leveling agent, an acrylic-based leveling agent, and a fluorine-based leveling agent.

3. The adhesive sheet according to claim 1 or 2, wherein the substrate is formed by applying and drying a liquid composition containing the polyvinyl chloride and the leveling agent to the surface of a support that has not been subjected to a release treatment.

4. 4. The pressure-sensitive adhesive sheet according to claim 1, wherein the surface of the pressure-sensitive adhesive layer opposite to the surface that comes into contact with the substrate is covered with a release liner.

5. a coating step of coating a liquid composition containing polyvinyl chloride, a plasticizer, and a leveling agent onto a support that has not been subjected to a release treatment; a solidification step of solidifying the composition coated on the support to form a substrate; a pressure-sensitive adhesive layer forming step of forming a pressure-sensitive adhesive layer on the surface of the base material formed on the support, The average degree of polymerization of the polyvinyl chloride is 1000 or more and 2000 or less, the content of the plasticizer in the base material is 25 parts by mass or more and 40 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride, the content of the leveling agent in the base material is 0.5 parts by mass or more and 20.0 parts by mass or less relative to 100 parts by mass of the polyvinyl chloride, A method for producing a pressure-sensitive adhesive sheet, wherein the thickness of the substrate is 5 μm or more and 200 μm or less.

6. The method for producing a pressure-sensitive adhesive sheet according to claim 5 , wherein the composition further contains an organic solvent in addition to the polyvinyl chloride and the leveling agent.

7. A printed matter, comprising the adhesive sheet according to claim 1 , and a printed portion formed by an inkjet method on the substrate of the adhesive sheet.

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