JPH05272099A - Pressure-sensitive adhesive sheet for re-releasable post card - Google Patents

Abstract

PURPOSE:To provide the pressure-sensitive sheet capable of reading the information on the adhered surface by again releasing a release layer therefrom, not causing troubles such as blockings, etc., and used for re-releasable pressure- sensitive post cards. CONSTITUTION:In the pressure-sensitive sheet produced by disposing an adhesive agent layer on a support and giving a re-releasable pressure-sensitive post card by pressing the sheet on a non-adhesive post card sheet, the pressure-sensitive sheet for the re-releasable post card is characterized by disposing the first adhesive agent layer on the whole surface of the support by a coating method and subsequently disposing the second adhesive agent layer on a part of the first adhesive agent layer by a printing method.

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 re-peelable pressure-sensitive adhesive postcards, in which information on the joint surface can be seen by peeling again.

[0002]

2. Description of the Related Art Confidential postcards of the type in which an adhesive label is attached to a portion on which personal information is placed and the information at that portion is concealed are in increasing demand due to the merit of being able to mail confidential information at a postcard fee. For this type of postcard,
Several types have already been put on the market, but none of them are still sufficient in terms of performance or cost. For example, the one described in Japanese Utility Model Publication No. 63-6870,
It is designed so that peeling occurs from the non-adhesive resin layer other than the adhesive layer that is the bonding surface, and once the label is peeled from the postcard, it cannot be easily re-bonded, and the label peeling is extremely stable. However, since the adhesive label used has a multi-layered structure, many steps are required for its manufacture, resulting in extremely high manufacturing cost and a small cost merit due to the low shipping fee. ing.

The inventors of the present invention previously filed Japanese Patent Application No. 1-27.
No. 0849 and No. 1-339995, the T-type peeling force is 10 g / 25 mm when the adhesive layers of the pressure-sensitive adhesive sheet are superposed facing each other and bonded by applying a pressure of 1 kg / cm ^2.
Using a pressure-sensitive adhesive sheet that satisfies the condition that the T-type peeling force is 50 g / 25 mm or more when bonded under a pressure of 300 kg / cm ² and pressure-treated with a non-adhesive sheet. Releasable postcards that can be joined together and that can read the information on the joined surface again by peeling off the joined surface are available in terms of manufacturing cost.
It was revealed that it was superior to the postcard of No. 0.

However, as a result of detailed examination, it has been found that such postcards also have points for further improvement. That is, when the conventional pressure-sensitive adhesive sheet is Z-folded and stored, the adhesive layers are likely to be in a so-called blocking state in which the adhesive layers are adhered to each other in the perforated portion of the sheet, near the marginal area, near the edge of the sheet, etc. , When trying to join the postcard sheet using the sheet in this state,
Problems such as misfeeds and paper jams are likely to occur.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a pressure-sensitive adhesive sheet for use in a removable pressure-sensitive adhesive postcard which does not cause the above-mentioned troubles.

[0006]

Means for Solving the Problems The inventors of the present invention have diligently studied the adhesive layer of a pressure-sensitive adhesive sheet, and as a result, use a pressure-sensitive adhesive sheet obtained by a specific process. As a result, they have found that stable pressure treatment can be performed, and have completed the present invention.

The present invention relates to a pressure-sensitive adhesive sheet, which comprises a support and an adhesive layer, and is joined to a non-adhesive postcard sheet under high pressure to form a removable pressure-sensitive adhesive postcard. For a releasable postcard, which is obtained by applying a first adhesive layer on the entire surface of a support by coating, and then providing a second adhesive layer on a part of the first adhesive layer by printing. It is a pressure-sensitive adhesive sheet.

[0008]

According to the present invention, blocking is not a problem even if the entire surface of the support is processed into a Z-folded shape, and the joined portion does not rise when joined to a postcard sheet under high pressure. The first adhesive layer having the bonding strength of 1) is provided, and then the second adhesive layer is printed on the first adhesive layer except for the perforations and other portions where blocking is likely to occur. It is a pressure-sensitive adhesive sheet that compensates for the shortage.

The adhesive used for forming the first adhesive layer and the second adhesive layer is, for example, ethylene-vinyl acetate resin, acrylic resin, vinyl chloride resin, vinylidene chloride resin, synthetic rubber resin. , Natural rubber resins, and the like, and those having a glass transition point of −100 to 0 ° C. are preferable.

A pigment for improving blocking resistance is usually added to the adhesive layer, and specifically, silica, kaolin, clay, calcium carbonate, aluminum hydroxide, zinc oxide, titanium oxide, melamine resin particles, Examples thereof include benzoguanamine resin particles, starch particles, pulp powder and the like. Incidentally, the pigment is usually 10 to 5 with respect to the adhesive.
Used in the range of 00% by weight.

Further, if necessary, the adhesive layer may be further dissolved in water such as casein, agar, gum arabic, sodium alginate, starch, oxidized starch, esterified starch, carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid and the like. Polymer, styrene-butadiene latex, latex such as acrylonitrile-butadiene latex, rosin resin and its derivatives, terpene resin, coumarone indene resin, xylene resin, alkylphenol resin, C
_{5 to} C ₉ petroleum resin and other tackifiers, various paraffin waxes, fatty acids and their derivatives, higher alcohols,
Release agents such as metal soaps and silicones, adhesive-containing capsules and oil capsules to improve adhesiveness, antistatic agents, thickeners, dispersants, preservatives, antioxidants, antifoaming agents, etc. Agents may be added.

The coating liquid used to form the adhesive layer is
Although any of an aqueous system, an organic solvent system and a solventless system (hot melt, ionizing radiation) can be used, an aqueous coating solution in which the above adhesive is an emulsion is usually used.

For the first adhesive layer, the coating liquid containing the above components is usually dried at a weight of 1 to 10 g / m using a coating machine such as an air knife coater, a blade coater or a bar coater.
It is formed by coating the entire surface of the support so as to be ² . The second adhesive layer has a dry weight of usually 0.3 to 1 using a printing machine such as gravure printing, screen printing, flexographic printing, letterpress printing, offset printing, etc.
It is formed by partial printing on the first adhesive layer so as to be 0 g / m ² . The printing of the second adhesive layer is preferable because it can be performed in the same steps as normal information printing, perforation processing, marginal processing, and the like.

Among the adhesive layers provided in this way, the adhesive layer set so that the adhesive force of the second adhesive layer is higher than that of the first adhesive layer has the most preferable balance between blocking and adhesive force. The adhesive strength can be controlled by appropriately selecting and using the above-mentioned adhesive, pigment or the like, or adjusting the coating amount.

The support used for forming the pressure-sensitive adhesive sheet includes, for example, high-quality paper, coated paper for printing (lightly coated paper, coated paper, art paper, cast coated paper, etc.), synthetic paper, and impregnated paper. Examples of the paper include paper, laminated paper, and metal vapor-deposited paper. Among them, high-quality paper and coated paper for printing are particularly preferable because they can be reused as waste paper. The method of making paper used for these is not particularly limited, and recycled paper recycled pulp may be contained. In addition, a sheet obtained by printing a tint block or the like on the above sheet may be used.

The pressure-sensitive adhesive sheet thus obtained is, if necessary, printed on the front surface and / or the back surface of the sheet (printing of information, printing of an adhesion-suppressing layer), perforation, marginal and punching. Is appropriately selected and applied to form a label, which is then Z-folded.

Examples of postcard sheets include high-quality paper,
Synthetic paper, impregnated paper, laminated paper, metallized paper, coated paper for printing (lightly coated paper, coated paper, art paper, cast coated paper, etc.), coated paper for recording (heat-sensitive recording paper, pressure-sensitive copying) Paper, electrostatic recording paper, thermal transfer image receiving paper, photographic paper, ink jet recording paper, etc.) are used. The method of making paper used for these is not particularly limited, and recycled paper recycled pulp may be contained.

This postcard sheet is appropriately subjected to a base printing such as an address column, an amount column, advertisement, printing of peeling stabilizing ink, and processing such as perforation and marginal as required, and is usually Z. Is folded. Subsequently, the personal information is recorded on a recording device such as a line printer.

Subsequently, the postcard sheet and the pressure-sensitive adhesive sheet are guided and processed in a pressure sealing device while the recording surface of the postcard sheet and the adhesive surface of the pressure-sensitive adhesive sheet are overlapped. As the pressure sealing device, a machine which is usually of a type that guides a sheet through a marginal hole, and which is appropriately equipped with a portion capable of performing processing such as slitting, cutting, folding and pressing of the sheet is used. Note that the postcard sheet and the pressure-sensitive adhesive sheet are not necessarily limited to those handled as continuous sheets, and may be handled as individual sheets.

The pressure treatment is usually carried out by using a pressure roll.
It is carried out under a pressure of ˜1000 kg / cm ² . At that time, it is more preferable that the sheet is equipped with a heating device because the adhesive force is stabilized by preheating the sheet to 30 to 60 ° C. The recording apparatus used in the present invention is a wet or dry electrophotographic method, thermal transfer recording method, thermal recording method, electrostatic recording method, electrolytic recording method, impact method, ink jet method, silver salt photography method, or the like. Is used.

[0021]

EXAMPLES Examples of the present invention will be described below, but it goes without saying that the present invention is not limited to these examples. In the examples, "parts" means "parts by weight" and "%" means "% by weight" unless otherwise specified.

Example 1 (Preparation of pressure-sensitive adhesive sheet) Acrylic acid was used as an adhesive.
Steal emulsion (product of Nippon Synthetic Rubber Co., Ltd., product
Name: AE-923) 80 parts (dry weight), synthetic pigment
Rika (Mizawa Chemical Co., Ltd., trade name: Mizukasil P-8)
32) and 80 parts of pulp powder and 40 parts of pulp powder are mixed to obtain a solid content.
The first adhesive coating liquid obtained by adjusting the concentration to 30% is 80 g /
m²4g / m dry weight on the base paper surface of the impregnated paper²Will be
The whole surface was smeared with sea urchin air knife coater. Then,
Change the solid content of acrylic ester emulsion AE-923
The second adhesive coating liquid obtained by adjusting to 30% was applied to the above-mentioned sheet
1g / m dry weight on 1 adhesive layer ²Letterpress to be
Partial printing (shaded area in Fig. 3) with a printing machine, and
Put the perforation and marginal after printing the underside on the back side
It was Z-folded to obtain a pressure-sensitive adhesive sheet.

(Preparation of postcard sheet) Undercoating is printed on the front and back surfaces of 145 g / m ² coated paper, and then perforations and margins are added, and the address, name, data, etc. are individually printed by an electrophotographic line printer. The information was output to obtain a Z-fold of the postcard continuous sheet (the sheet of FIG. 1 was Z-folded with two postcards as one unit).

(Preparation of Removable Postcard) After introducing the pressure-sensitive adhesive sheet onto the postcard sheet into the pressure-sealing device while superposing the sheet as shown in FIG. 4, first pre-bonding and then marginal Cut perforation and further 500kg / cm ²
Removable postcard by pressurizing with pressure (Fig. 5: plan view, Fig. 6:
A cross-sectional view) was obtained. (Evaluation) The Z-folded pressure-sensitive adhesive sheet had no blocking tendency and the pressure treatment was extremely stable. or,
The re-peeling postcard obtained had good adhesiveness and the peeling was stable.

Comparative Example 1 (Preparation of pressure-sensitive adhesive sheet) 100 parts (dry weight) of acrylic acid ester emulsion AE-923, Mizukasil P
-832 (60 parts) and pulp powder (40 parts) were mixed, and the solid content concentration was adjusted to 30% to obtain an adhesive coating liquid of 80 g / m ^2.
The base paper surface of the impregnated paper of 1 was smeared with an air knife coater so that the dry weight was 9 g / m ² . Then, after performing underprinting on the front surface and the back surface of the sheet, Z-fold was performed with perforations and marginal to obtain a pressure-sensitive adhesive sheet.

(Preparation of Removable Postcard) The above pressure-sensitive adhesive sheet was formed on the postcard sheet obtained in the same manner as in Example 1.
After introducing into the pressure sealing device while superimposing like
First, pre-bonding was performed, then marginal and perforations were cut, and further pressure was applied at a pressure of 500 kg / cm ² to obtain a removable postcard (FIG. 5: plan view, FIG. 6: sectional view). (Evaluation) The Z-folded pressure-sensitive adhesive sheet had a strong blocking tendency, and pressure treatment could not be stably performed. However, the re-peeling postcard obtained had good adhesiveness and the peeling was stable.

Comparative Example 2 (Preparation of pressure-sensitive adhesive sheet) 80 parts (dry weight) of acrylic ester emulsion AE-923, Mizukasil P-83
2 80 parts of a mixture of pulp powder 40 parts of dry weight is 4g / m ² of an adhesive coating solution obtained by adjusting the solid concentration to 30% to the original paper of impregnated paper 80 g / m ² So that the entire surface was smeared with an air knife coater. Then, after performing underprinting on the front surface and the back surface of the sheet, Z-fold was performed with perforations and marginal to obtain a pressure-sensitive adhesive sheet.

(Preparation of Removable Postcard) The above-mentioned pressure-sensitive adhesive sheet was formed on the postcard sheet obtained in the same manner as in Example 1.
After introducing into the pressure sealing device while superimposing like
First, pre-bonding was performed, then marginal and perforations were cut, and further pressure was applied at a pressure of 500 kg / cm ² to obtain a removable postcard (FIG. 5: plan view, FIG. 6: sectional view). (Evaluation) The Z-folded pressure-sensitive adhesive sheet had no blocking tendency and the pressure treatment was extremely stable. However, it was found that the removable postcard obtained had poor adhesiveness and was not practical.

[0029]

EFFECTS OF THE INVENTION The pressure-sensitive adhesive sheet for removable postcards of the present invention has no blocking tendency and can be pressure-treated extremely stably. The re-peelable postcard obtained also had good adhesiveness and the peeling for obtaining information was stable.

[Brief description of drawings]

FIG. 1 is a plan view showing an example of a non-adhesive postcard sheet.

FIG. 2 is a plan view showing an example of a pressure-sensitive adhesive sheet.

FIG. 3 is a plan view from the back surface (bonding surface) of FIG.

FIG. 4 shows a state in which the pressure-sensitive adhesive sheet of FIG. 2 is superposed on the postcard sheet of FIG.

FIG. 5 is an example of a removable postcard of the present invention, which is obtained by guiding the stacked sheets of FIG. 4 into a general-purpose pressure sealing device, cutting marginal and perforated lines, and then applying pressure. ..

6 is a sectional view taken along line AA of the removable postcard of FIG.

[Explanation of symbols]

 1: Postcard sheet 2: Perforation 3: Marginal hole 4: Personal information (address / name) 5: Personal information (data) 6: Pressure-sensitive adhesive sheet 7: Second adhesive coating liquid printing area 8: Re Peelable postcard 9: Postcard 10: Label 11: Support 12: First adhesive layer 13: Second adhesive layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B42D 15/08 D 7008-2C G09F 3/10 B 7028-5G

Claims (2)

[Claims] 1. A pressure-sensitive adhesive sheet, which comprises a support and an adhesive layer, and is bonded onto a non-adhesive postcard sheet under high pressure to form a removable pressure-sensitive adhesive postcard. A pressure-sensitive adhesive sheet for removable postcards, which is obtained by applying a first adhesive layer on the entire upper surface by coating, and then providing a second adhesive layer on a part of the first adhesive layer by printing. Adhesive sheet. 2. The pressure-sensitive adhesive sheet for a removable postcard according to claim 1, wherein the second adhesive layer has stronger adhesiveness than the first adhesive layer.