JP3118151B2 - Adhesive sheet for printing, label and release agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-sensitive adhesive sheet for printing which can be used for rewinding as a wound body in which a pressure-sensitive adhesive layer is adhered to the back surface of a sheet, and which can form a pattern with a thermal transfer ink on a release treatment layer thereof. The present invention relates to a label having excellent fixability, abrasion resistance and solvent resistance of a pattern using the sheet.

[0002]

2. Description of the Related Art Conventionally, a film substrate has an adhesive layer on one side and a coating film made of a release agent on the other side, and the adhesive layer is adhered to a release coating film on the back side and wound. There has been known an adhesive sheet which can be put to practical use in the form of a body or the like, and thus does not require the adhesive layer to be covered with a separate separator. However, the pattern cannot be fixed by thermal transfer of the ink to the release coat film, and it has been difficult to use the ink for printing such as forming a label.

On the other hand, a printing sheet having an ink receiving layer comprising a mixture of a styrene / polyolefin polymer and a thermoplastic resin having a melting point of 200 ° C. or higher (Japanese Patent Laid-Open No. Sho 62-29)
No. 9391) is also known which is provided with a thermal transfer pattern made of a wax-based ink. However, even if an adhesive layer is attached to the back surface of a printing sheet having such an ink receiving layer to form an adhesive printing sheet, the adhesive layer is adhered to the ink receiving layer on the back surface and practically used in the form of a roll or the like. Is practically impossible because of difficulty in rewinding the wound body.Therefore, it is necessary to cover the pressure-sensitive adhesive layer with a separate separator for practical use. However, there is a problem that the separator covering the above becomes an unnecessary product such as dust.

[0004]

According to the present invention, the adhesive layer can be rewound and used as a wound body in which the adhesive layer is adhered to the back surface of the sheet. Therefore, a separate separator for covering the adhesive layer is not required. A pressure-sensitive adhesive sheet for printing that can fix a pattern by thermal transfer ink on the back surface of the sheet, and can be issued on an occasion by pattern formation by a thermal transfer method using the sheet, and fixability of the thermal transfer pattern,
An object is to obtain a label having excellent scratch resistance and solvent resistance.

[0005]

According to the present invention, a polyolefin having a viscosity-average molecular weight of 5,000 to 6,000,000 is formed on one side of a polyolefin having a viscosity average molecular weight of 5,000 to 6,000,000 on the other side, and a release agent is used per 100 parts by weight of the polyolefin. 0.01 to 10 parts by weight,
One or more of inorganic pigment, carbon or metal powder
A pressure-sensitive adhesive sheet for printing, characterized by having a release treatment layer for fixing a thermal transfer ink containing a colorant as a component in a state where it cannot be wiped with an organic solvent, and a viscosity of the release treatment layer in the pressure-sensitive adhesive sheet for printing. An object of the present invention is to provide a label provided with a solvent-wiping-resistant thermal transfer pattern composed of an ink containing a polyolefin having an average molecular weight of 5,000 to 300,000 and the above-mentioned coloring agent.

[0006]

[Function] By forming a release treatment layer by blending a release treatment agent with polyolefin, a conventional adhesive tape can be used as a wound body or the like in which an adhesive layer is adhered to a release treatment layer provided on the back side thereof. Similarly, it can be used for rewinding, so that a separate separator covering the adhesive layer can be dispensed with, and the ink can be thermally transferred to the release treatment layer to fix the pattern. In this case, by using an ink containing a polyolefin and a colorant as components, a heat transfer pattern having excellent fixability, abrasion resistance, and solvent resistance can be formed by good fusion bonding of the polyolefin in the release treatment layer and the ink. Can be. Therefore, even a commercially available thermal transfer printer can form a label by adding a pattern on an occasional basis.

[0007]

The printing pressure-sensitive adhesive sheet of the present invention has a pressure-sensitive adhesive layer on one side and a viscosity average molecular weight of 5,000 to
6,000,000 polyolefins are used as film-forming components, and the release agent is used in an amount of 0.01 to 10 per 100 parts by weight of the polyolefin.
Parts by weight, containing inorganic pigment, carbon or metal powder
It comprises a release treatment layer that fixes the thermal transfer ink containing one or more colorants as a component so that it cannot be wiped off with an organic solvent, and the label has a release treatment layer in the pressure-sensitive adhesive sheet for printing, It is provided with a solvent-wiping-resistant thermal transfer pattern composed of an ink containing a polyolefin having a viscosity average molecular weight of 5,000 to 300,000 and the above-mentioned coloring agent. An example of a label (adhesive sheet for printing) is shown in FIG. 1 is a pressure-sensitive adhesive sheet for printing, 11 is a release treatment layer thereof,
12 is an adhesive layer and 2 is a thermal transfer pattern. Reference numeral 3 denotes an adherend.

The pressure-sensitive adhesive sheet for printing may be in the form of a sheet in which a pressure-sensitive adhesive layer is exposed on one side and a release treatment layer containing a release treatment agent containing polyolefin as a film-forming component is exposed on the other side. It can be formed in an appropriate form. Examples thereof include a form in which an adhesive layer is provided on a sheet-shaped release processing layer as illustrated in FIG. 1, and a release processing layer 11 on one side of a reinforcing base material 13 as illustrated in FIG. And a composite form having an adhesive layer 12.

[0009] The above-mentioned composite form includes a method in which a release treatment layer and an adhesive layer are provided on a sheet-like reinforcing substrate by a heat laminating method, an extrusion coating method, or the like. Or a method of impregnating a molten release agent or the like, a method of interposing a sheet-like reinforcing substrate in the release processing layer, a method of mixing a fibrous reinforcing substrate in the release processing layer, or the like. It may be formed appropriately.

[0010] Therefore, as the above-mentioned reinforcing base material, an appropriate material such as a resin coating layer or film, fiber or cloth, paper or nonwoven fabric, metal foil, net or wire may be used. The physical properties such as heat resistance of the reinforcing substrate may be appropriately determined according to the purpose of use. For example, a reinforcing substrate made of a heat-resistant polymer such as polyester, polyimide, fluororesin, or polyamide may be used. By selecting the reinforcing base material, it is possible to easily form a pressure-sensitive adhesive sheet or label for printing, which is flexible and has good curved surface adhesion.

The release treatment layer contains polyolefin as a film-forming component. There is no particular limitation on the type of polyolefin used, and polyethylene, polypropylene, or the like is generally used. The polyolefin has a viscosity average molecular weight of 5 from the viewpoints of solvent resistance, heat melting property, and fixability as solvent wiping resistance for fixing a thermal transfer ink containing a predetermined colorant to a state where it cannot be wiped with an organic solvent. Thousand to 6
One million, especially four million or less, particularly 1.5 million or less are used.

A release treatment agent is added to the release treatment layer in order to impart releasability in addition to the thermal transfer ink fixability based on polyolefin. The addition amount is polyolefin 10
0.01 to 10 parts by weight, preferably 0.1 to 10 parts by weight per 0 parts by weight
8 parts by weight, especially 1 to 5 parts by weight. If the addition amount is less than 0.01 part by weight, the effect of exhibiting releasability is poor, and 1
If the amount exceeds 0 parts by weight, the release treatment agent is deposited on the surface of the release treatment layer, and the fixing property of the ink tends to be deteriorated. As the release agent, for example, an appropriate one such as a known release agent such as a silicone-based, long-chain alkyl-based, or fluorine-based adhesive tape can be used, and there is no particular limitation.

As described above, a fibrous or other reinforcing base material can be mixed into the release treatment layer for the purpose of compounding, and an appropriate additive such as a white pigment for coloring can be blended. The content of the additive is generally 30% by weight or less from the viewpoint of solvent resistance and the like. If necessary, measures such as improvement of contrast with the pattern to be provided may be applied to the reinforcing base material in combination with the reinforcing base material.

Further, an antioxidant can be added to the release treatment layer for the purpose of improving the heat resistance of the polyolefin. The compounding amount is 0.01 parts by weight per 100 parts by weight of the polyolefin from the viewpoint of improving heat resistance and preventing precipitation on the surface.
10 to 10 parts by weight, preferably 0.1 to 5 parts by weight, especially 0.2 to 2 parts by weight
Parts by weight are preferred. As the antioxidant, a suitable compound such as a compound known as a polyolefin such as aromatic amines, phenols, sulfur compounds, phosphorus compounds, hydrazines and oxamides can be used.

The thickness of the release treatment layer can be appropriately determined according to the purpose of use, the form of the pressure-sensitive adhesive sheet for printing, and the like. Even in the case of a composite form, the thickness of the release treatment layer is 1 μm in view of strength and solvent resistance. It is preferable that the release treatment layer has a thickness of not less than the thickness. When polyethylene is used to form the release treatment layer, electron beam irradiation is effective for improving heat resistance. The irradiation amount is 1 to 20 Mrad from the viewpoint of improving heat resistance due to an increase in crosslink density and preventing reduction in heat storage stability due to irradiation deterioration.
Particularly, 5 to 15 Mrad is preferable.

The pressure-sensitive adhesive layer provided on the pressure-sensitive adhesive sheet for printing is used for bonding to an adherend in the case of a label or the like, and is also bonded to a release treatment layer on the back surface to form a roll or the like. This eliminates the need for a separate separator that covers the adhesive layer. The pressure-sensitive adhesive sheet for printing can be formed by attaching the adhesive layer to the release layer or the side thereof, or can be formed by attaching the release layer to the adhesive layer or the side thereof. It can be formed in a manner.

For forming the adhesive layer, an appropriate adhesive substance can be used. In general, for example, a rubber-based adhesive, an acrylic-based adhesive, a silicone-based adhesive, a vinyl alkyl ether-based adhesive, and a polyvinyl alcohol-based adhesive are used. An organic agent such as an adhesive, a polyvinylpyrrolidone-based adhesive, a polyacrylamide-based adhesive, or a cellulose-based adhesive is used.

The adhesive layer is formed by a method in which an adhesive layer is provided on a separator by a suitable method such as a rolling method such as a calender roll method, a sheet forming method such as a doctor blade method or a gravure roll coater method, and transferred. Alternatively, it can be performed by adhering to a release treatment layer or the like by an appropriate method such as a method of coating on the release treatment layer. The thickness of the adhesive layer to be provided can be determined according to the purpose of use, and is generally 1 to 500 μm.
It is said.

The label of the present invention can be formed by applying a thermal transfer pattern composed of an ink containing a polyolefin and a colorant to the release treatment layer of the pressure-sensitive adhesive sheet for printing. For the ink, for example, one or two or more colorants and a polyolefin are mixed by heating with an appropriate kneading machine such as a roll mill or a three-roll mill, or if necessary, using a polyolefin-soluble solvent such as a roll mill or a pot mill. Can be prepared as a paste-like fluid by mixing with an appropriate kneader.

The type of polyolefin used for forming the ink is not particularly limited, and polyethylene, polypropylene and the like are generally used. Solvent resistance and thermal meltability, or general-purpose ink by the thermal transfer printer of the transfer bondable or a point by Lipo Li olefins such as the solvent wipeability
It is to a viscosity average molecular weight of 5,000 to 300,000 preferably 2
00,000 or less, Ru is used particularly of 6 from 1,000 to 10,000.

[0021] As the coloring agent, a non-machine-based pigments, carbon
Alternatively , one or more metal powders are used . Various carbons can be preferably used for forming the black ink.

Examples of inorganic pigments include white substances such as silica, titania, alumina, zinc white, zirconia, calcium oxide, mica, manganese oxide / alumina, chromium oxide / tin oxide, iron oxide, cadmium sulfide / sulfide. Red substance such as selenium, blue substance such as cobalt oxide, zirconia / vanadium oxide, chromium oxide / divanadium pentoxide, black substance such as chromium oxide / cobalt oxide / iron oxide / manganese oxide, chromate, permanganate , Zirconium / silicon / praseodymium, vanadium / tin, chrome /
Typical examples thereof include yellow substances such as titanium / antimony, green substances such as chromium oxide, cobalt chromium, and alumina chromium, and pink substances such as aluminum / manganese and iron / silicon / zirconium.

The proportion of the colorant and the polyolefin used in the ink is appropriately determined depending on the contrast with the pressure-sensitive adhesive sheet for printing, the heat transfer pressure-bonding property, and the like, but is generally 50 to 500 parts by weight, preferably 100 to 100 parts by weight of the polyolefin. Up to 300 parts by weight of colorant is used.

An ink sheet such as a print ribbon, which is necessary for forming a pattern by a thermal transfer method, is formed by, for example, holding an ink on a supporting substrate made of a film, cloth, or the like by an application method, an impregnation method, or the like. Can be. As the supporting substrate, polyester, polyimide,
A conventional film such as a plastic film such as a fluororesin or a cloth made of a fiber such as polyamide or polyester may be used. For improving the adhesion of the ink layer, a method of undercoating the supporting base material with wax or the like is effective.

The thickness of the ink layer in the ink sheet is as follows:
The thickness is generally 0.2 to 5 μm, and preferably 0.8 to 1.5 μm. If the thickness is less than 0.2 μm, the hiding power may be poor, and if it exceeds 5 μm, the ink layer may be sheared, failing to perform good thermal transfer, and failing to form a good pattern.

The pattern formed by the thermal transfer system using a thermal transfer printer or the like is optional. An arbitrary thermal transfer pattern such as a print pattern, a picture pattern, and a barcode pattern may be provided. When an identification label is formed, it is preferable that a good contrast or a difference in color tone is formed between the printing adhesive sheet and the ink pattern. For the purpose of fixing the applied pattern more firmly, the pattern may be subjected to a heat treatment via a heat roll or the like as necessary after thermal transfer of the pattern.

The printing pressure-sensitive adhesive sheet or label of the present invention can be used for identifying various articles such as ceramics, glass products, ceramic products, metal products, enamel products, resin products, wood products, and paper products. It can be preferably used for various purposes such as providing a mark, providing a shipping label, or providing other patterns. In particular, it can be preferably used for an adherend that needs to undergo a washing step or a wiping step using a solvent. The adherend may be in any form, such as a flat form or a container form.

[0028]

According to the present invention, the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet for printing can be adhered to the release treatment layer on the back surface and used as a wound body so that the pressure-sensitive adhesive layer can be unwound. In addition to eliminating the need for a separate separator to cover, it is also possible to thermally transfer an ink containing a predetermined colorant to the release treatment layer and fix the pattern to a solvent wiping resistance that cannot be wiped with an organic solvent. Fixation, abrasion resistance,
A thermal transfer pattern having excellent solvent resistance can be formed. Therefore, an arbitrary pattern can be provided on an occasion by a thermal transfer method using a thermal transfer printer or the like, and a necessary label can be issued at any time.

[0029]

【Example】

Example 1 A kneaded product composed of 100 parts (parts by weight, the same applies hereinafter) of polyethylene having a viscosity average molecular weight of about 300,000, 3 parts of a silicone-based release agent, and 0.4 parts of a phenolic antioxidant was applied to a thickness of about 50 μm.
Extrusion lamination on one side of glassine paper (basis weight 80 g) to form a release treatment layer having a thickness of 20 μm, and a thickness of 2 μm on the other side.
An acrylic pressure-sensitive adhesive layer having a thickness of 0 μm was formed to obtain a pressure-sensitive adhesive sheet for printing. The pressure-sensitive adhesive layer was formed by applying a toluene solution containing 100 parts of polybutyl acrylate having a viscosity average molecular weight of about 1,000,000 and 2 parts of a crosslinking agent by a doctor blade method, and drying by heating.

On the other hand, 100 parts of carbon powder was added to 100 parts of polyethylene having a viscosity average molecular weight of about
, And apply the uniform dispersion to a 6 μm-thick polyester film with a thickness of 0.8 μm using a hot-melt gravure coating machine to obtain an ink sheet. Using a printer to print by thermally transferring the ink to the release treatment layer of the pressure-sensitive adhesive sheet for printing,
Got the label.

Comparative Example 1 A kneaded product consisting of 100 parts of polyethylene having a viscosity average molecular weight of about 300,000 and 0.4 part of a phenolic antioxidant was extrusion-laminated on one side of glassine paper having a thickness of about 50 μm (basis weight: 80 g). Example 2 except that an ink receiving layer (without release agent) having a thickness of 20 μm was formed on the adhesive sheet for printing having an acrylic adhesive layer having a thickness of 20 μm on the other surface. A label was obtained according to 1.

Comparative Example 2 1 g / m ² of a silicone release agent was applied to the surface of the ink receiving layer.
In the same manner as in Comparative Example 1 except that the coating was applied at a rate of 1% to form a release treatment coat, and printing was performed on the release treatment coat.

Comparative Example 3 Example 1 except that a commercially available wax-based ink sheet was used.
Labels were obtained according to.

Evaluation Test Printability The print condition of the labels obtained in Examples and Comparative Examples was examined to determine whether or not printing was possible.

The adhesive layer of the adhesive sheet for printing obtained in Examples and Comparative Examples was adhered to the back surface to form a wound body, and it was examined whether or not it could be unwound.

Solvent Resistance The labels obtained in Examples and Comparative Examples were pressed against a glass plate via the adhesive layer of the labels, and the printed surface of the labels was wiped with a non-woven fabric impregnated with a solvent to check the remaining state of the prints. As the solvent, acetone, toluene, dimethylacetamide (DMA),
Alternatively, methylene chloride (MC) was used.

The results are shown in the following table.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of a label (adhesive sheet for printing).

FIG. 2 is a cross-sectional view of another embodiment of the pressure-sensitive adhesive sheet for printing.

[Explanation of symbols]

 1: adhesive sheet for printing 11: release treatment layer 12: adhesive layer 13: reinforcing substrate 2: pattern layer 3: adherend

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Itsuro Takeshita 1-1-2 Shimohozumi, Ibaraki-shi, Osaka Nippon Denko Corporation (72) Inventor Katsuo Kuramoto 1-1-1, Shimohozumi, Ibaraki-shi, Osaka No. 2 Nippon Denko Co., Ltd. (72) Inventor Satoshi Ito 1-1-2 Shimohozumi, Ibaraki City, Osaka Prefecture Nippon Denko Co., Ltd. (72) Inventor Zenzo Honda 1, Shimohozumi Ibaraki City, Osaka Prefecture JP-A-6-270563 (JP, A) JP-A-3-229776 (JP, A) JP-A-4-85022 (JP, A) JP-A-3-140344 (JP, A) JP-A-4-299186 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09J 7/02 C09F 3/02 C09F 3/10 B41M 5/26

Claims (4)

(57) [Claims] 1. A pressure-sensitive adhesive having a pressure-sensitive adhesive layer on one side and a polyolefin having a viscosity average molecular weight of 5,000 to 6,000,000 as a film-forming component on the other side.
0.01 to 10 parts by weight, containing an inorganic pigment, carbon or
A pressure-sensitive adhesive sheet for printing, comprising a release treatment layer for fixing a thermal transfer ink containing one or more colorants of metal powder as a component so that it cannot be wiped off with an organic solvent. 2. The pressure-sensitive adhesive sheet for printing according to claim 1, wherein the pressure-sensitive adhesive layer is made of an acrylic pressure-sensitive adhesive, and the release agent is a silicone-based release agent. 3. The polyolefin having a viscosity average molecular weight of 5,000 to 300,000 and an inorganic pigment, carbon or metal powder in the release treatment layer of the pressure-sensitive adhesive sheet for printing according to claim 1 or 2.
A label provided with a solvent-wiping-resistant thermal transfer pattern made of an ink containing one or more colorants as components. 4. An inorganic cosmetic comprising a polyolefin having a viscosity average molecular weight of 5,000 to 6,000,000 and containing a release agent in an amount of 0.01 to 10 parts by weight per 100 parts by weight of the polyolefin.
Release treatment agent, which forms a film that fixes a thermal transfer ink containing a colorant as a component comprising one or more of a colorant , a carbon or a metal powder so that the thermal transfer ink cannot be wiped with an organic solvent. .