JP2000328018A - Pressure-sensitive adhesive label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure-sensitive adhesive label in which the layer of a release agent having excellent adhesion and wear resistance can have been formed and hence the use of a releasing paper can be omitted and which label can keep excellent releasability and various performances such as tackiness and pressure-sensitive adhesive strength. SOLUTION: A pressure-sensitive adhesive label has a substrate having at least one side printed thereon, on one side of which substrate the layer of a release agent based on an addition reaction type of silicone is formed by way of an intermediate layer comprising at least one kind of a resin selected from the group consisting of an acrylic resin, a urethane resin and a polyol resin, and on the other side of which substrate the layer of a pressure-sensitive adhesive is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive label which does not require release paper.

[0002]

2. Description of the Related Art Conventionally, pressure-sensitive adhesive labels on which decorations, indications, and the like are printed have been widely used. Such adhesive labels are roughly classified into the following two types.

[0003] One type of pressure-sensitive adhesive label is based on a substantially transparent thermoplastic synthetic resin-based film, and is printed on the surface of the substrate on which the pressure-sensitive adhesive layer is to be formed, ie, printed on the reverse side (mirror image of an actual display). ), A pressure-sensitive adhesive layer is formed on the printed surface, and release paper (release paper) is laminated for covering and protecting the pressure-sensitive adhesive layer. The pressure-sensitive adhesive label has a substantially opaque thermoplastic resin-based film as a base material, and performs printing, that is, surface printing (the same image as an actual display) on a surface of the base material on which the pressure-sensitive adhesive layer is not formed,
If necessary, a protective coat layer is provided on the printed surface, an adhesive layer is formed on the non-printed surface of the substrate, and then a release paper is laminated for covering and protecting the adhesive layer. It is.

Since the above-mentioned conventional adhesive label uses release paper, it is necessary to peel off the release paper before attaching the adhesive label, and the peeled release paper becomes waste. When the release paper is peeled by hand, it takes much time and workability deteriorates, and when the release paper is peeled by machine, it is necessary to use a device for peeling or winding the peeled release paper. There is a problem that a collecting and collecting device and the like are required, and the amount of capital investment is increased.

[0005] In order to cope with the above-mentioned problems caused by using release paper, a release agent layer is provided on the surface (back surface) of the pressure-sensitive adhesive label on which the pressure-sensitive adhesive layer is not formed, and the adhesive label is laminated in a sheet shape. It is also conceivable that the pressure-sensitive adhesive layer is covered or protected by using a roll shape without using release paper.

However, in the case of the addition reaction type silicone, which is most commonly used as a release agent, since a platinum-based catalyst is used, it is used in a base material, a printing ink, a protective coating layer of a printing ink, and the like. In addition, if a metal salt compound, a nitrogen-containing compound, a sulfur-containing compound, a phosphorus-containing compound, etc. are contained, the platinum-based catalyst is poisoned by these compounds, and the crosslinking of the addition reaction type silicone becomes insufficient. In addition, there is a problem in that poor quality such as poor release (peeling failure) due to the release of the release agent and poor adhesion due to migration of unreacted addition-reaction silicone into the pressure-sensitive adhesive layer are liable to occur.

On the other hand, if a condensation reaction type silicone or a polymer having a long-chain alkyl group is used as a release agent, quality deterioration due to the poisoning action of the above-mentioned catalyst does not occur, but productivity and releasability (peelability) are low. There is a problem that it is insufficient and it is difficult to obtain an adhesive label having high commercial value.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention can form a release agent layer having excellent adhesion and abrasion resistance. An object of the present invention is to provide an adhesive label capable of maintaining various properties such as moldability and tack and adhesive strength.

[0009]

The pressure-sensitive adhesive label according to the present invention is selected from the group consisting of an acrylic resin, a urethane resin, and a polyol resin on at least one side of a substrate having printing on one side. Characterized in that an addition reaction type silicone release agent layer is formed via an intermediate layer made of at least one resin, and an adhesive layer is formed on the other surface of the base material. And

In the pressure-sensitive adhesive label according to the present invention, at least one selected from the group consisting of an acrylic resin, a urethane resin and a polyol resin is provided on the surface on which the substrate is printed (printed surface). A method (surface printing method) in which an addition-reaction-type silicone-based release agent layer is formed via an intermediate layer made of and a pressure-sensitive adhesive layer is formed on the other surface (non-printing surface) of the substrate. When the substrate is substantially transparent, an additional reaction type silicone release agent layer is formed on the non-printing surface of the substrate via the intermediate layer, and an adhesive is formed on the printing surface of the substrate. Layer formation method (back side printing method)
May be taken.

When a transparent substrate such as a thermoplastic synthetic resin film is used as the substrate, a front surface printing method or a back surface printing method may be employed. It is preferable to adopt a backside printing method which is excellent in durability since it is not performed.

When an opaque substrate such as kraft paper is used as the substrate, a surface printing method must be used.

The base material of the pressure-sensitive adhesive label according to the present invention includes:
Although not particularly limited, for example, adhesion of a thermoplastic synthetic resin film, cellophane, high-quality paper, kraft paper, glassine paper, coated paper, cast-coated paper, resin-impregnated paper, metal foil laminated film or metal-deposited film, etc. Various types of base materials generally used as a base material for a label are exemplified, and are preferably used.

The thermoplastic synthetic resin film that can be used as the base material is not particularly limited. For example, polyolefin resin films such as polypropylene and polyethylene, and polyester resin films such as polyethylene terephthalate and polybutylene terephthalate can be used. , Nylon 6, nylon 66, polyamide resin film, vinyl chloride resin film, various thermoplastic synthetic resin films such as styrene resin film,
It is preferably used. These thermoplastic synthetic resin films may be unstretched films or uniaxially or biaxially stretched films.

The substrate may be composed of a single layer, or may be composed of a plurality of laminated layers.

The thickness of the substrate is not particularly limited, but is preferably 300 μm or less.
More preferably, it is 10 to 100 μm.

The substrate used in the present invention may contain, as necessary, a tackifier, a filler, a softener, a plasticizer, a coloring agent, a stabilizer, and the like, as long as the object of the present invention is not hindered.
One or more of various additives such as an antioxidant, an ultraviolet absorber, an antistatic agent, a lubricant (slip agent), and a flame retardant may be contained.

On one or both sides of the base material, a surface oxidation treatment such as a corona discharge treatment is used to improve the adhesion (anchor property) with a printing ink, an intermediate layer, a pressure-sensitive adhesive layer and the like described later. Or a surface treatment such as primer coating.

In the present invention, the printing ink used for printing for decoration and display on at least one side of the substrate is not particularly limited, and any of various printing inks generally used can be used. And the printing method may be any of the commonly used gravure printing method and flexographic printing method. Further, a protective coat layer for protecting the printing ink may be provided on the printing surface.

In the pressure-sensitive adhesive label according to the present invention, an acrylic resin, a urethane resin and a polyol resin are interposed between one surface of the base material and an addition-reaction type silicone release agent layer formed on the surface. It is necessary that an intermediate layer made of at least one resin selected from the group consisting of

By providing the above-mentioned intermediate layer between the surface of the substrate and the addition-reaction type silicone release agent layer, the above-mentioned metal salt compound or the like can be formed in the substrate, in the printing ink or in the protective coating layer of the printing ink. Even when a nitrogen-containing compound, a sulfur-containing compound, a phosphorus-containing compound, etc. are contained, the platinum-based catalyst contained in the addition-reaction type silicone-based release agent layer is toxic by these compounds. It can be effectively prevented. As a result, the cross-linking of the addition-reaction type silicone progresses sufficiently, so that poor quality such as poor release due to the release of the release agent layer and poor adhesion due to migration of the unreacted addition-reaction silicone into the pressure-sensitive adhesive layer. Can be effectively suppressed.

The acrylic resin that can be used as the intermediate layer is not particularly limited.
Homopolymers or copolymers of alkyl (meth) acrylates such as methyl (meth) acrylate and ethyl (meth) acrylate, in which some or all of the hydrogens in the alkyl group are hydroxyl, carboxyl, amino, etc. Homopolymers or copolymers of substituted alkyl (meth) acrylates substituted by functional groups, alkyl (meth) acrylates and / or substituted alkyl (meth) acrylates, and styrene copolymerizable therewith , Α
-Methyl styrene, vinyl acetate, α, β-monoethylenically unsaturated carboxylic acid, copolymer with a vinyl monomer having an unsaturated bond such as vinyl toluene, or a mixture thereof. Species or two or more species are suitably used. Here, (meth) acryl means acryl or methacryl.

The urethane resin which can be used as the intermediate layer is not particularly limited. For example, polyisocyanate compounds such as hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate and tolylene diisocyanate; Reaction products with polyol compounds such as polyester diols, polyester diols, polycarbonate diols, and lactone polyester polyols.
Species or two or more species are suitably used.

The polyol-based resin that can be used as the intermediate layer is not particularly limited.
Examples thereof include polyether diol, polyester diol, polycarbonate diol, and lactone polyester polyol, and one or more of these are preferably used.

The acrylic resin, urethane resin and polyol resin may be used alone or in combination of two or three.

The intermediate layer made of at least one resin selected from the group consisting of the above-mentioned acrylic resin, urethane resin and polyol resin is provided with a cohesive force to improve abrasion resistance. It is preferable to include a polyisocyanate compound as a crosslinking agent.

The polyisocyanate compound which can be used as the crosslinking agent is not particularly limited, but includes, for example, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate,
Examples thereof include tolylene diisocyanate and the like, or adducts thereof with a polyol such as trimethylolpropane, and one or more of these are suitably used.

In the composition for the intermediate layer forming the intermediate layer,
At least one selected from the group consisting of acrylic resins, urethane resins and polyol resins as main components
Seed resins and polyisocyanate compounds as a crosslinking agent, as required, within a range that does not hinder achievement of the object of the present invention, tackifying resins, coupling agents, fillers, softeners, plasticizers, coloring agents One or more of various additives such as a stabilizer, an antioxidant, an ultraviolet absorber, an antistatic agent, and a flame retardant may be contained.

The form of the composition for the intermediate layer is not particularly limited, and may be a solvent type composition, a non-aqueous dispersion type composition, an emulsion type composition, a dispersion type composition, a hot melt type composition. The composition may be in any form such as a photocurable composition, but when the polyisocyanate compound is contained in the composition for the intermediate layer, the dispersibility, stability, etc. are taken into consideration, and the solvent type is most preferred. preferable.

The method of applying the composition for the intermediate layer to the substrate surface is not particularly limited, and may be a general method such as a bar coater, a gravure roll coater, an air knife coater, a flow coater, a spray coater, and a hot melt coater. After applying using a typical coating facility, the intermediate layer may be formed by performing drying, cooling, light irradiation and the like as necessary.

The coating amount of the composition for the intermediate layer is not particularly limited, but is preferably 0.1 to 5 g / m ² in solid content. The coating amount of the intermediate layer composition is 0.1
If it is less than g / m ² , coating unevenness is likely to occur, and the above-mentioned effect of providing the intermediate layer may not be sufficiently obtained. Conversely, if it exceeds 5 g / m ² , the above-mentioned effect will no longer be obtained. Not only will it not improve anymore, but it will also be economically disadvantageous.

In the pressure-sensitive adhesive label according to the present invention, it is necessary that an addition reaction type silicone release agent layer is formed on the intermediate layer provided on the base material.

By using an addition-reaction silicone as a release agent, higher productivity and releasability can be obtained as compared with the case where, for example, a condensation-reaction silicone or a polymer having a long-chain alkyl group is used as a release agent. Can be obtained.

The above-mentioned addition reaction type silicone is a releasable silicone obtained by crosslinking a high molecular siloxane having two or more vinyl groups at the molecular chain terminals with an organohydrogenpolysiloxane using a platinum-based catalyst. This is a high-molecular silicone capable of forming an elastic film rich in oil, and has been generally used for release paper.

In the present invention, one or more of the addition reaction type silicones conventionally used for the release paper are preferably used.

The form of the release agent composition is not particularly limited, but is preferably a solvent dilution type or a non-solvent type.

The method for applying the release agent composition onto the intermediate layer is not particularly limited, and the same general coating equipment as used for applying the intermediate layer composition is used. After application, the composition may be dried, if necessary, and then heated to promote crosslinking to form a release agent layer.

The coating amount of the release agent composition is not particularly limited, but is preferably 0.1 to 5 g / m ² in solid content.

The coating amount of the release agent composition is 0.1 g / m
^If it is less than ² , it may be difficult to secure coating accuracy, and sufficient release properties may not be obtained.
^If it exceeds ² , not only does the releasability no longer improve, but it is also disadvantageous economically.

The pressure-sensitive adhesive used for the pressure-sensitive adhesive label according to the present invention is not particularly limited.
Various types of pressure-sensitive adhesives commonly used for pressure-sensitive adhesive labels and pressure-sensitive adhesive tapes, such as natural rubber-based pressure-sensitive adhesives, synthetic rubber-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, and silicone-based pressure-sensitive adhesives, are listed. It is preferably used.

The form of the above-mentioned pressure-sensitive adhesive is not particularly limited, and may be a solvent-type pressure-sensitive adhesive, a non-aqueous dispersion-type pressure-sensitive adhesive, an emulsion-type pressure-sensitive adhesive, a dispersion-type pressure-sensitive adhesive, a hot-melt-type pressure-sensitive adhesive, or a light-curable pressure-sensitive adhesive. Any form such as a mold adhesive may be used.

The method of applying the above-mentioned pressure-sensitive adhesive to the substrate surface is not particularly limited, and may be applied by using a general coating machine such as a roll coater, a comma coater, a die coater or a hot melt coater. After directly applying to the specified surface of the material,
If necessary, drying, cooling, performing light irradiation or the like to form an adhesive layer, a so-called direct coating method may be employed, or coating on a separator, if necessary, drying, After performing cooling, light irradiation, etc. to form an adhesive layer,
A so-called transfer method in which the image is transferred onto a predetermined surface of the base material may be employed.

The coating amount of the pressure-sensitive adhesive is not particularly limited, but is preferably 5 to 100 g / m ² in solid content.

If the coating amount of the pressure-sensitive adhesive is less than 5 g / m ² , sufficient tackiness and adhesive strength may not be obtained,
Conversely, if it exceeds 100 g / m ² , the holding power and the creep resistance may decrease.

In the above coating, a predetermined surface of the substrate is subjected to a surface oxidation treatment such as corona discharge or the like in order to further improve the adhesion (anchor property) between the substrate and the pressure-sensitive adhesive. An undercoat layer (primer layer) such as a modified natural rubber or synthetic rubber may be provided.

The adhesive label of the present invention thus obtained is cut (perforated) in order to improve usability.
May be provided. The method of providing the cuts (perforations) is not particularly limited, and may be provided in advance on the base material or may be provided in the final step of the production of the pressure-sensitive adhesive label.

In the pressure-sensitive adhesive label according to the present invention, an intermediate layer made of a specific resin is provided between the base material and the addition-reaction type silicone release agent layer. The platinum-based catalyst contained in the product does not suffer from the poisoning effect of the silicone crosslinking inhibitor contained in the printing ink or the substrate. Therefore, since the crosslinking of the addition-reaction type silicone proceeds sufficiently, poor quality such as poor release due to the release of the release agent layer and poor adhesion due to migration of the unreacted addition-reaction type silicone into the pressure-sensitive adhesive layer are caused. Does not happen.

Further, since the addition-reaction type silicone is used as the release agent, the productivity and the releasability are improved as compared with the case where the condensation-reaction type silicone or the polymer having a long-chain alkyl group is used as the release agent. Excellent.

Furthermore, since it is not necessary to use release paper, all problems such as generation of waste, deterioration of workability, and increase in equipment investment caused by use of release paper are solved.

[0050]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(Example 1)

(1) Preparation of Adhesive Label A biaxially oriented polypropylene film (thickness: 60 μm) having both surfaces subjected to corona discharge treatment was used as a base material, and a polyurethane-based red ink (trade name “Ramiol Mark II”) was applied to one surface of the base material.
I / Red Red 370 ", manufactured by Sakata Inx Co., Ltd.). An acrylic resin (trade name: GR-5331, manufactured by Mitsubishi Rayon Co., Ltd.) is coated on the other surface (non-printing surface) of the base material so that the coating amount is 1 g / m ^{2 in} solid content. Thus, an intermediate layer was formed. Next, an addition reaction type silicone (trade name “SD7223”, manufactured by Toray Dow Corning Silicone Co., Ltd.) was applied on the intermediate layer at a coating amount of 0.6 g in solid content.
/ M ² and dried and cured at 130 ° C. for 10 seconds to form a release agent layer. Then, an acrylic pressure-sensitive adhesive (trade name "Olivein BP")
S-3233D ", manufactured by Toyo Ink Mfg. Co., Ltd.) so as to have a coating amount of 25 g / m < ² > in solid content, and dried.
It was wound up to produce an adhesive label (back side printing type).

(2) Evaluation The performance of the pressure-sensitive adhesive label obtained above (adhesion of release agent,
The abrasion resistance, ball tack, and adhesion of the release agent were evaluated by the following methods. The results were as shown in Table 1.

Adhesiveness of the release agent: The coated surface of the release agent was strongly rubbed ten times with a finger, and the presence or absence of the release agent was visually observed, and the adhesion of the release agent was evaluated according to the following criteria. did. [Judgment criteria] ○ ‥‥ No release agent release was observed × ‥‥ Release agent release was observed and it could not be used

Abrasion resistance of release agent: The coated surface of the release agent was strongly rubbed 10 times with gauze, and the degree of damage to the coated surface of the release agent was visually observed. Abrasion was evaluated. [Judgment Criteria] ○ ‥‥ No damage was observed on the coating surface of the release agent △ 若干 Some damage was recognized on the coating surface of the release agent, but it was usable × ‥‥ Release agent Severe damage to the coated surface of the

Ball tack: JIS Z-0237
The ball tack (ball No.) of the pressure-sensitive adhesive label was measured in accordance with "Testing method of pressure-sensitive adhesive tape / pressure-sensitive adhesive sheet".

Adhesive force: The adhesive force (N / 25 mm) of an adhesive label was measured according to JIS Z-0237.

(Example 2) As a resin for the intermediate layer, an acrylic resin "GR-5331" / a urethane resin (trade name "Samprene IB-450", manufactured by Sanyo Chemical Industries, Ltd.) /
Polyol-based resin (trade name “Acrydick 48-44”
3 ", manufactured by Dainippon Ink and Chemicals, Inc.) = 50/17/33
An adhesive label (back side printing type) was produced in the same manner as in Example 1 except that the mixed resin (weight ratio of solid content) was used.

(Example 3) As a composition for the intermediate layer, a polyisocyanate compound (trade name "Coronate L", manufactured by Nippon Polyurethane Industry Co., Ltd.) was used as a crosslinking agent with respect to 100 parts by weight of the mixed resin used in Example 2. Was prepared in the same manner as in Example 1 except that a resin composition containing 5 parts by weight of was added as a solid content.

(Example 4) In the same manner as in Example 3 except that printing was performed on the substrate surface on the side of the intermediate layer and the release agent layer, and an adhesive layer was provided on the non-printing surface, An adhesive label (surface printing type) was obtained.

Example 5 bleached kraft paper (basis weight 75 g /
m ² ) is based on polyethylene-laminated kraft paper in which low-density polyethylene having a thickness of 20 μm is laminated on one side, and a polyurethane-based red ink “Ramiol Mark III / Red Red 370” is applied to the polyethylene-laminated surface of the base material.
Printing was performed using. Next, an acrylic resin “GR-5331” was applied on the surface on which the printing was performed so that the coating amount was 1 g / m ^{2 in} solid content, to form an intermediate layer.
Next, an addition-reaction silicone (trade name “SRX357”, manufactured by Toray Dow Corning Silicone Co., Ltd.) was applied on the intermediate layer so that the coating amount was 0.6 g / m ^{2 in} solid content, and 130 ° C. For 10 seconds to form a release agent layer. An acrylic pressure-sensitive adhesive “Olivine BPS-3233D” was applied on the other surface (non-printing surface) of the base material so that the coating amount was 25 g / m ^{2 in} solid content, and then dried. And wound up to produce an adhesive label (surface printing type).

(Example 6) An adhesive label (surface printing type) was produced in the same manner as in Example 5 except that the mixed resin used in Example 2 was used as the resin for the intermediate layer.

Example 7 Example 5 was repeated except that the resin composition used in Example 3 was used as the composition for the intermediate layer.
In the same manner as in the above case, an adhesive label (surface printing type) was produced.

(Comparative Example 1) An adhesive label (back side printing type) was produced in the same manner as in Example 1 except that the intermediate layer was not provided.

(Comparative Example 2) An adhesive label (surface printing type) was produced in the same manner as in Example 5 except that the intermediate layer was not provided.

The performance of the eight types of pressure-sensitive adhesive labels obtained in Examples 2 to 7 and Comparative Examples 1 and 2 was evaluated in the same manner as in Example 1. The results were as shown in Table 1.

[0067]

[Table 1]

As is clear from Table 1, the pressure-sensitive adhesive labels of Examples 1 to 7 according to the present invention had excellent adhesiveness of the release agent and good or excellent abrasion resistance.

On the other hand, the pressure-sensitive adhesive labels of Comparative Examples 1 and 2 in which the intermediate layer was not provided had poor adhesion and abrasion resistance of the release agent. In addition, these pressure-sensitive adhesive labels were inferior in ball tack and pressure-sensitive adhesive strength.

This is considered to be because the intermediate layer constituting the present invention effectively shields the crosslinking inhibitor of the addition-reaction type silicone contained in the printing ink or the base material from the silicone crosslinking catalyst.

[0071]

As described above, the pressure-sensitive adhesive label according to the present invention exhibits excellent releasability and various properties such as tackiness and adhesive strength, and is therefore preferably used mainly as a decorative or display pressure-sensitive adhesive label. Can be Further, since the release paper is not used, various problems such as generation of waste, deterioration of workability, and increase in equipment investment caused by use of the release paper are not caused.

Claims (1)

[Claims] 1. An intermediate layer comprising at least one resin selected from the group consisting of an acrylic resin, a urethane resin and a polyol resin, on one surface of a substrate on which at least one surface is printed. An adhesive label, wherein an addition reaction type silicone-based release agent layer is formed through the base material, and an adhesive layer is formed on the other surface of the base material.