JPH08100159A - Adhesive sheet for printing, label and release agent - Google Patents

Abstract

(57) [Summary] [Purpose] The adhesive layer can be rewound and used as a wound body that is adhered to the back surface of the sheet, and therefore a separate separator that covers the adhesive layer is not required, and the back surface of the sheet is A pressure-sensitive adhesive sheet for printing that can fix a pattern with a thermal transfer ink, and a label that can be issued on occasion with pattern formation by a thermal transfer method using the sheet and has excellent fixability, scratch resistance, and solvent resistance of the thermal transfer pattern. To get. A pressure-sensitive adhesive sheet for printing, comprising a pressure-sensitive adhesive layer (12) on one surface, and a heat-transfer ink-fixable release processing layer (11) on the other surface, containing a release processing agent containing polyolefin as a film forming component. A label comprising the release treatment layer (11) of the pressure-sensitive adhesive sheet for printing and a thermal transfer pattern (2) made of an ink containing a polyolefin and a colorant as components.

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 rewound and used as a wound body having an adhesive layer adhered to the back surface of a sheet, and which can form a pattern by a thermal transfer ink on its release treatment layer. The present invention relates to a label having excellent fixability, scratch resistance, and solvent resistance of a pattern formed using the sheet.

[0002]

2. Description of the Related Art Conventionally, a film base material has an adhesive layer on one side and a coating film with a release agent on the other side, and the adhesive layer is adhered to a release coating film on the back surface and wound. There has been known a pressure-sensitive adhesive sheet which can be put to practical use in the form of a body or the like and therefore does not require the pressure-sensitive adhesive layer to be covered with a separate separator. However, the pattern cannot be fixed by thermally transferring the ink to the releasable coat film, and it is difficult to use it for printing such as label formation.

On the other hand, a printing sheet having an ink receiving layer composed of a mixture of a styrene / polyolefin polymer and a thermoplastic resin having a melting point of 200 ° C. or more (JP-A-62-29).
No. 9391), a label provided with a thermal transfer pattern made of a wax-based ink is also known. However, even if an adhesive layer is attached to the back side of a printing sheet having such an ink receiving layer to form an adhesive type printing sheet, the adhesive layer is adhered to the ink receiving layer on the back side for practical use in the form of a roll or the like. It is substantially impossible to rewind the wound body, therefore it is necessary to cover the pressure-sensitive adhesive layer with a separate separator for practical use, and the pressure-sensitive adhesive layer for practical use as a label. There was a problem that the separator that covered the above became an unnecessary item such as dust.

[0004]

According to the present invention, the pressure-sensitive adhesive layer can be rewound and used as a wound body or the like which is adhered to the back surface of the sheet. Therefore, a separate separator covering the pressure-sensitive adhesive layer is unnecessary, and A printing pressure-sensitive adhesive sheet that can fix a pattern of thermal transfer ink on the back surface of the sheet, and can be issued on the occasion of pattern formation by the thermal transfer method using the sheet, and the fixability of the thermal transfer pattern,
It is an object to obtain a label having excellent scratch resistance and solvent resistance.

[0005]

SUMMARY OF THE INVENTION According to the present invention, there is provided a pressure-sensitive adhesive layer on one surface and a heat-transferable ink-fixing release processing layer containing a release processing agent containing polyolefin as a film forming component on the other surface. The present invention provides a label comprising a pressure-sensitive adhesive sheet for printing, and a release treatment layer in the pressure-sensitive adhesive sheet for printing, which is provided with a thermal transfer pattern made of an ink containing a polyolefin and a colorant as components. .

[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 the adhesive layer is adhered to the release treatment layer provided on the back side thereof. Similarly, rewinding can be used, so that a separate separator covering the adhesive layer can be eliminated, and the ink can be thermally transferred to the release treatment layer to fix the pattern. In that case, by using an ink containing a polyolefin and a colorant as a component, a thermal transfer pattern having excellent fixability, scratch resistance, and solvent resistance can be formed by good melt pressure bonding of the polyolefin in the release treatment layer and the ink. You can Therefore, a label can be formed by applying a pattern on a commercial thermal transfer printer.

[0007]

Examples of constituent elements of the invention: The pressure-sensitive adhesive sheet for printing of the present invention has a pressure-sensitive adhesive layer on one side and contains a release treatment agent with polyolefin as a film forming component on the other side, and release treatment for fixing heat transfer ink. The label has a layer, and the label has a release treatment layer in the pressure-sensitive adhesive sheet for printing, on which a thermal transfer pattern made of an ink containing a polyolefin and a colorant is provided. Example of label (adhesive sheet for printing)
It was shown to. Reference numeral 1 is a pressure-sensitive adhesive sheet for printing, 11 is a release treatment layer thereof, 12 is a pressure-sensitive adhesive layer, and 2 is a thermal transfer pattern. In addition, 3 is an adherend.

The pressure-sensitive adhesive sheet for printing may be in the form of a sheet in which the pressure-sensitive adhesive layer is exposed on one side and the 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. As an example thereof, as shown in FIG. 1, a sheet-like release treatment layer is provided with an adhesive layer, and as shown in FIG. 2, the reinforcing base material 13 has the release treatment layer 11 on one surface and the other surface. Examples thereof include a composite form having an adhesive layer 12.

The above-mentioned composite form is not limited to a method in which a release treatment layer or an adhesive layer is provided on a sheet-shaped reinforcing base material by a thermal laminating method or an extrusion coating method. Or a method of impregnating a molten release treatment agent, a method of interposing a sheet-like reinforcing base material in the release treatment layer, a method of mixing a fibrous reinforcing base material in the release treatment layer, etc. It may be formed appropriately.

Therefore, as the reinforcing base material, an appropriate material such as a resin coating layer or film, fiber or cloth, paper or non-woven cloth, metal foil, net or wire may be used. The physical properties such as heat resistance of the reinforcing base material may be appropriately determined according to the purpose of use, and for example, a reinforcing base material made of a heat resistant polymer such as polyester, polyimide, fluororesin or polyamide may also 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. The type of polyolefin used is not particularly limited, and generally polyethylene or polypropylene is used. A polyolefin that can be preferably used in terms of solvent resistance, heat melting property, and fixing property of a thermal transfer ink has a viscosity average molecular weight of 5,000 to 6,000,000, especially 4,000,000 or less, particularly 1.5,000,000 or less.

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 amount of addition is 10
0.01 to 10 parts by weight, especially 0.1 to 0 parts by weight
8 parts by weight, particularly 1 to 5 parts by weight is preferred. If the amount added is less than 0.01 parts by weight, the effect of developing releasability is poor and 1
If the amount is more than 0 parts by weight, the release treatment agent is deposited on the surface of the release treatment layer, and the fixability of the ink is likely to be lowered. As the release treatment agent, an appropriate release agent such as a known release agent for adhesive tapes of silicone type, long chain alkyl type, fluorine type, etc. can be used, and there is no particular limitation.

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

An antioxidant may be added to the release treatment layer for the purpose of improving the heat resistance of the polyolefin. The blending amount is 0.01 parts by weight per 100 parts by weight of the polyolefin from the viewpoint of the effect of improving heat resistance and prevention of precipitation on the surface.
-10 parts by weight, especially 0.1-5 parts by weight, especially 0.2-2
Parts by weight are preferred. As the antioxidant, suitable compounds such as aromatic amines, phenols, sulfur compounds, phosphorus compounds, hydrazines, oxamides, and other known compounds for polyolefins can be used.

The thickness of the release treatment layer can be set to an appropriate thickness according to the purpose of use and the form of the pressure-sensitive adhesive sheet for printing. Even in the case of a composite form, the thickness is 1 μm from the viewpoint of strength and solvent resistance. It is preferable that the release treatment layer has a thickness of at least one. When polyethylene is used for forming the release treatment layer, electron beam irradiation treatment is effective for improving heat resistance. The irradiation amount is 1 to 20 Mrad from the viewpoint of improving the heat resistance by increasing the crosslink density and preventing the deterioration of heat resistant storage stability due to irradiation deterioration.
Especially, 5 to 15 Mrad is preferable.

The pressure-sensitive adhesive layer provided on the pressure-sensitive adhesive sheet for printing is for adhering to an adherend when it is used as a label or the like, and is also adhered to the release treatment layer on the back surface to form a roll or the like. Therefore, a separate separator for covering the adhesive layer is unnecessary. The pressure-sensitive adhesive sheet for printing can be formed by attaching the pressure-sensitive adhesive layer to the release treatment layer or its side, or can be formed by attaching the release treatment layer to the pressure-sensitive adhesive layer or its side. Can be formed by a method.

For forming the adhesive layer, an appropriate adhesive substance can be used. Generally, for example, a rubber adhesive, an acrylic adhesive, a silicone adhesive, a vinyl alkyl ether adhesive, a polyvinyl alcohol adhesive. Organic agents such as adhesives, polyvinylpyrrolidone-based adhesives, polyacrylamide-based adhesives, and cellulose-based adhesives are used.

The adhesive layer is formed by forming an adhesive layer on the separator and transferring it by an appropriate method such as a rolling method such as a calendar roll method or a sheet forming method such as a doctor blade method or a gravure roll coater method. Alternatively, it can be performed by adhering to the 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 kind or two or more kinds of colorants and polyolefin are heated and mixed by an appropriate kneader such as a roll mill or a three roll mill, or if necessary, a solvent capable of dissolving polyolefin is used, for example, a roll mill or a pot mill. Can be mixed with an appropriate kneader to prepare a paste-like fluid.

The type of polyolefin used to form the ink is not particularly limited, and generally polyethylene or polypropylene is used. Polyolefins that can be preferably used in terms of solvent resistance, heat melting property, and transfer pressure bonding property of ink by a general-purpose heat transfer printer are
The viscosity average molecular weight is 5,000 to 300,000, preferably 200,000 or less, and particularly 6,000 to 10,000.

As the colorant, for example, an organic or inorganic pigment, carbon, metal powder or the like may be used. Various carbons can be preferably used for forming the black ink. Examples of the organic pigments include azo pigments, phthalocyanine pigments, triphenylmethane pigments, metal complex pigments, vat dye pigments, quinacridone pigments, and isoindolinone pigments.

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

The use ratio of the colorant and the polyolefin in the ink is appropriately determined depending on the contrast with the pressure-sensitive adhesive sheet for printing, the thermal transfer pressure-bonding property, etc., but is generally 50 to 500 parts by weight, preferably 100 parts by weight per 100 parts by weight of the polyolefin. ~ 300 parts by weight of colorant are used.

An ink sheet such as a printing ribbon necessary for forming a pattern by the thermal transfer method is formed by holding the ink on a supporting base material such as a film or a cloth by a coating method, an impregnation method, or the like. You can As the supporting substrate, polyester, polyimide,
A usual film such as a plastic film made of fluororesin or a cloth made of fibers such as polyamide or polyester may be used. To improve the adhesion of the ink layer, it is effective to undercoat the supporting substrate with wax or the like.

The thickness of the ink layer in the ink sheet is
0.2 to 5 μm is general, and 0.8 to 1.5 μm is preferable. 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 and good thermal transfer may not be performed, and a good pattern may not be formed.

The pattern formed by the thermal transfer method by a thermal transfer printer or the like is arbitrary. An arbitrary heat transfer pattern such as a print pattern, a picture pattern, a bar code pattern may be provided. When forming an identification label, it is preferable that a good contrast or difference in color tone be formed between the printing pressure-sensitive adhesive sheet and the ink pattern. Note that, for the purpose of more firmly fixing the applied pattern, it is also possible to perform a heat treatment via a heat roll or the like after the thermal transfer of the pattern, if necessary.

The pressure-sensitive adhesive sheet or label for printing of the present invention comprises identification such as bar codes for 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 mark application, shipping label application, and other pattern application. In particular, it can be preferably used for an adherend that needs to undergo a cleaning step and a wiping step with 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 printing pressure-sensitive adhesive sheet can be rewound and used as a wound body by adhering the pressure-sensitive adhesive layer to the release treatment layer on the back surface. A separate separator to cover can be eliminated, and the pattern can be fixed by thermally transferring the ink to the release treatment layer, forming a thermal transfer pattern with excellent fixability, scratch resistance, and solvent resistance. can do. Therefore, an arbitrary pattern can be arbitrarily applied by a thermal transfer system such as a thermal transfer printer, and a necessary label can be issued at any time.

[0029]

【Example】

Example 1 A kneaded product composed of 100 parts of polyethylene having a viscosity average molecular weight of about 300,000 (parts by weight, the same applies hereinafter), 3 parts of a silicone-based release agent, and 0.4 parts of a phenol-based antioxidant has a thickness of about 50 μm.
Extrusion-laminated on one side of m (grammage 80 g) glassine paper to form a 20 μm thick release treatment layer, and the other side has a thickness of 2
A 0 μm acrylic pressure-sensitive adhesive layer was formed to obtain a pressure-sensitive adhesive sheet for printing. The 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 cross-linking agent by a doctor blade method and heating and drying.

On the other hand, 100 parts of carbon powder was added to 100 parts of polyethylene having a viscosity average molecular weight of about 8,000 to obtain a temperature of about 200.degree.
To obtain an ink sheet by applying the uniform dispersion to a 6 μm-thick polyester film with a thickness of 0.8 μm using a hot-melt gravure coater to obtain an ink sheet and commercially available thermal transfer. A printer is used to thermally transfer and print the ink on the release treatment layer of the pressure-sensitive adhesive sheet for printing,
Got the label.

Comparative Example 1 A kneaded product comprising 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 onto one side of glassine paper having a thickness of about 50 μm (basis weight of 80 g). Example in which an ink-receiving layer having a thickness of 20 μm (without a release agent) was formed on the other surface, and an acrylic adhesive layer having a thickness of 20 μm was provided on the other surface of the ink-receiving layer for printing. 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.
A label was obtained in the same manner as in Comparative Example 1 except that the release treatment coat was formed by coating at a ratio of 1. 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.
A label was obtained according to.

Evaluation Test Printability The printing states of the labels obtained in the examples and comparative examples were examined to see if printing was possible.

Rewinding Property The pressure-sensitive adhesive layers of the printing pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples were adhered to the back surface thereof to form a wound body, and it was examined whether or not the film could be unwound.

Solvent resistance The label obtained in Examples and Comparative Examples was pressure-bonded to a glass plate through an adhesive layer, and the non-woven fabric impregnated with a solvent was wiped to wipe the printed surface of the label to examine the residual state of printing. As the solvent, acetone, toluene, dimethylacetamide (DMA),
Alternatively, methylene chloride (MC) was used.

The above results are shown in the following table.

[Brief description of drawings]

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

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

[Explanation of symbols]

 1: Adhesive sheet for printing 11: Release treatment layer 12: Adhesive layer 13: Reinforcing base material 2: Pattern layer 3: Adherend

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical display location C09J 7/02 JKV G09F 3/02 T 3/10 J (72) Inventor Izuro Takenoshita Ibaraki City, Osaka Prefecture Shimohozumi 1-2, Nitto Denko Corporation (72) Inventor Yasuo Kuramoto Ibaraki, Osaka Prefecture Shihohozumi 1-2-2 Nitto Denko Corporation (72) Inventor Satoshi Ito Ibaraki, Osaka Prefecture Shimohozumi 1-2, Nitto Denko Corporation (72) Inventor Zenzo Honda 1-2-1, Shimohozumi, Ibaraki City, Osaka Prefecture Nitto Denko Corporation

Claims (5)

[Claims] 1. A pressure-sensitive adhesive sheet for printing, comprising a pressure-sensitive adhesive layer on one surface and a heat-transfer ink-fixable release processing layer containing a mold-releasing agent containing polyolefin as a film forming component on the other surface. . 2. The pressure-sensitive adhesive layer comprises an acrylic pressure-sensitive adhesive, and the polyolefin forming the release treatment layer has a viscosity average molecular weight of 5
The pressure-sensitive adhesive sheet for printing according to claim 1, wherein the release treatment agent is a silicone-based release agent and the content thereof is 0.01 to 10 parts by weight per 100 parts by weight of the polyolefin. 3. A label, wherein the release treatment layer of the pressure-sensitive adhesive sheet for printing according to claim 1 or 2 is provided with a thermal transfer pattern made of an ink containing polyolefin and a colorant as components. 4. The label according to claim 3, wherein the polyolefin forming the ink has a viscosity average molecular weight of 5,000 to 300,000. 5. A mold release treatment agent comprising a polyolefin containing a mold release treatment agent and forming a film capable of fixing thermal transfer ink.