JPH0437594A - Confidental postcard - Google Patents

Abstract

PURPOSE:To obtain a superior confidental postcard using one kind of adhesive by a method wherein the edge part of the bonding part of the postcard is folded to be all or partially bonded with each other through two adhesive layers, and the non-edge part is folded to be bonded with each other through one adhesive layer. CONSTITUTION:An address and data (e) are written on a sheet provided with one kind of adhesive (h) on a substrate. The sheet is folded at a folding perforation line (f), and the surfaces are opposed to each other and bonded under pressure. In the obtained postcard, the non-edge part of the bonding part is bonded through one adhesive layer with a low adhesion power. On the other hand, the edge part is bonded through two adhesive layers with a high adhesion power. In this manner, only by providing one kind of adhesive layer on the substrate, the parts having two kinds of adhesive properties can be formed on the postcard. Therefore, the postcard can be formed by using a general-purpose printing press. It is especially preferable that the high-adhesion part is unreleasable because a superior information security can be obtained. As the adhesive, an ethylene-vinyl acetate resin and an acrylic resin can be exemplified, but the glass transition point thereof is preferably -100 - 0 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a postcard that can protect the confidentiality of information, and more particularly to a confidential postcard that can be produced using a general-purpose printing machine.

[Conventional technology]

After recording information using a line printer or the like on the joint side of a sheet made of a combination of pressure-sensitive adhesive sheets or a combination of a pressure-sensitive adhesive sheet and a non-adhesive sheet,
A method of bonding these surfaces under strong pressure to make a confidential postcard is described in Japanese Patent Application No. 1-270849, No. 1-339995, Japanese Utility Model Application No. 1-145470, No. 1145472, No. 1145473, etc. It is expected to become popular due to the economic advantage of being able to send confidential information by mail for the price of a postcard.

However, Japanese Patent Application Nos. 1-270849 and 1-33
For confidential postcards such as No. 9995, which are set so that the entire joint surface has the same strength of removability, if the adhesive strength is set to be weak so that the recipient can easily peel it off, it will be difficult to handle it during shipping etc. There is a risk that unintended discrepancies may occur and confidential information may be leaked.

On the other hand, if the adhesive strength is set to be strong enough to prevent such unintended peeling at all, when the recipient peels off the paper to obtain the information, the paper is likely to tear and there is a risk that the information will become unreadable. etc., it is difficult to maintain a balance between adhesiveness and releasability.

On the other hand, Utility Model Application No. 1-145470, No. 1-145472
No. 1-145473, adhesive layers with different adhesion strengths are provided on a support to make the edge part of the joint of the postcard non-peelable and the non-edge part set to be re-peelable. Postcards do not have the risk of unintentional peeling or paper tearing when peeled off, but in order to obtain such sheets, it is necessary to print with two types of ink with different adhesion strengths, which requires hot air or infrared rays. It is necessary to have at least two drying devices such as the above, and it has the disadvantage that it can only be produced using an extremely large and special printing machine.

[Problem to be solved by the invention]

The object of the present invention is to use a general-purpose printing machine to obtain a confidential postcard that exhibits strong adhesiveness in all or a portion of the edge portion of the joint, and in which the non-edge portion exhibits weak adhesiveness.

[Means to solve the problem]

As a result of studies, the present inventors discovered that a postcard with excellent confidentiality can be obtained with a single type of adhesive by selectively using the joints between the adhesive layers and the joints between the adhesive layer and the non-adhesive sheet. Ta.

The present invention provides a confidential postcard in which sheets having an adhesive layer on at least a portion of the base material are bonded together under pressure, in which the entire or part of the edge portion of the joint of the postcard is bonded to each other by the adhesive layer, and This is a confidential postcard characterized in that the edge portions are joined by a layer of adhesive.

[Effect]

The present invention will be explained using the drawings.

Figures 1, 4, and 7 show conventional confidential postcards. In order to reduce the risk of unintentional peeling, these sheets are coated with an adhesive layer (C) that exhibits strong adhesion and an adhesive layer (d) that exhibits weak adhesion on a support.
An example is one obtained by writing 1, then bending at the bending perforation if) so that the surfaces face each other, and then joining under pressure.

The confidentiality postcard of the present invention, as shown in FIGS. 2 and 3,
A type of adhesive layer (address, data fe) is written on a sheet provided with hl on a support, and then it is bent at the folding perforation (f) so that the surfaces face each other, and then pressure bonded. This is a postcard with the same functions as Figure 1.

The thus obtained postcard exhibits weak adhesive properties because the non-edge portions of the joints are bonded by one adhesive layer, while the edge portions are bonded by two adhesive layers and exhibit strong adhesive properties. As described above, the postcard of the present invention can form areas exhibiting two types of adhesive properties simply by providing one type of adhesive layer on the support, and therefore can be produced using a general-purpose printing machine.

Among these, it is particularly preferable that the strongly adhesive portion is non-peelable because the security of information is excellent.

Another embodiment of the present invention is shown in FIGS. 5 and 6. As shown in the figure, a kind of adhesive layer (hl) is provided on the support, and an address and data tel are written on a sheet with a window (1) punched out of the support, and then a folding sewing machine (100) is used. F) is bent and pressure bonded with the faces facing each other to form a functional postcard similar to that shown in Fig. 4.

Further embodiments of the present invention are shown in FIGS. 8, 9, and 10.
Examples include those shown in the figure. As shown in the figure, a type of adhesive layer (address, data fe) is written on a sheet with HL, and then it is bent at the bending perforation (f) so that the surfaces are facing each other, and then pressure bonded. It becomes a postcard with the same function as in Figure 7.

Incidentally, the confidential postcard of the present invention has no risk of peeling off at an unintended time. To obtain information, simply cut off the edge part with scissors or the like and open the weakly adhesive non-edge part. Further, perforations (ig) for cutting may be provided in advance.

Adhesives used for forming the adhesive layer of the present invention include:
Examples include ethylene-vinyl acetate resins, acrylic resins, vinyl chloride resins, vinylidene chloride resins, synthetic rubber resins, natural rubber resins, etc. Among them, those having a glass transition point of -100''C to O℃ Preferably.

Pigments such as silica, kaolin, clay, calcium carbonate, aluminum hydroxide, zinc oxide, titanium oxide, melamine resin particles, benzoguanamine resin particles, and starch particles are usually added to the above adhesives to improve blocking resistance. Ru. The blending ratio of pigment to adhesive is 10 to 50
It is used in a range of about 0% by weight.

Furthermore, if necessary, casein, agar, gum arabic,
Sodium alginate, starch, oxidized starch, etherified starch,
Esterified starch, carboxymethylcellulose, hydroxyethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, water-soluble polymers such as polyacrylic acid, latex such as styrene-butadiene latex, acrylonitrile-butadiene latex, rosin resin and its derivatives, terpene resin, Tackifiers such as coumaron indene resin, xylene resin, alkylphenol resin, C6-C8 petroleum resin, release agents such as various paraffins, waxes, fatty acids and their derivatives, high alkaline earth metal soaps, silicones, etc., and adhesives. Auxiliary agents such as adhesive-containing capsules or oil capsules, antistatic agents, thickeners, dispersants, preservatives, antioxidants, antifoaming agents, etc. may be added to enhance the agent strength.

On the other hand, as the base material for the postcard, for example, high-quality paper, impregnated paper, synthetic paper, coated paper, laminated paper, gold-i deposited paper, etc. are used. In addition, the sheet contains casein, polyvinyl alcohol, ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, ethyl cellulose, ethyl hydroxyethyl cellulose, acetyl cellulose, cellulose acetate propionate, cellulose acetate butyrate, nitrocellulose. A sheet provided with a layer mainly composed of a resin such as , polyvinyl butyral, polyvinyl chloride, or polystyrene is preferable in order to obtain stable releasability over time. Although the sheets of the base material may be separated from each other, it is more practical and preferable to have them connected.

The amount of adhesive coating liquid applied to Murakami is usually 4 to 4 times.
20 g/m, screen printing, flexo printing,
It is provided by conventionally known printing methods such as offset printing and letterpress printing.

Among the adhesive layers provided in this way, when the surfaces of the adhesive layers are stacked facing each other and bonded by applying a pressure of 1 kg/cd, the weight is 10 g/25 tl as measured based on JIS K 6833-1980. Indicates the following T-type peel force,
In addition, 300 kg/
Particularly preferred is one that exhibits a T-peel force of 50 g/25 Tsuru or more when bonded under a pressure of - because it has an extremely good balance between adhesiveness and peelability.

In the present invention, in addition to applying the above-mentioned adhesive coating, the sheets before being pressure bonded are subjected to base printing or perforations or marginal processing by letterpress printing, offset printing, flexo printing, etc. as necessary. After personal data is printed using an impact or non-impact line printer, etc., it is printed using a sealer or the like with a pressure roll for 50 minutes.
~1000kg/cJ! The paper is processed under pressure to form a postcard.

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

Example 1 (Creation of confidentiality postcard shown in Figure 8) 100 parts of acrylic acid ester emulsion (manufactured by Japan Synthetic Rubber ■, trade name: AE-923) was used as an adhesive.
Dry weight), 100 parts of synthetic silica (manufactured by Mizusawa Kagaku Kogyo ■, trade name: MIZUKASIL P-832) as a pigment, and 10 parts of starch particles were mixed to adjust the solid content concentration to 40%, and the coating liquid was mixed at 130 g/rri. dry weight 8 on one side of high-quality paper.
g/m as shown in Figure 8, and then perform base printing, perforation and marginal processing, address and data printing using a line printer, and then fold the sheet using a sealer with a pressure roll. A confidential postcard as shown in Figure 8 was created by joining the two together.

The resulting postcard did not peel off during handling, and by cutting the perforations and peeling it off, it was possible to see the record of the joint.

〔effect〕

The confidential postcard of the present invention uses a type of coating liquid as a coating liquid for adhesion to form a postcard having a copolymer adhesive part and a weakly adhesive part, and has an extremely low risk of peeling off unexpectedly. there were.

[Brief explanation of the drawing]

FIGS. 1, 4, and 7 are plan views showing postcards formed by the conventional method before and after pressure treatment, and FIGS. 2, 3, 5, 6, FIG. 8, FIG. 9, and FIG. 10 are plan views showing postcards according to the present invention. Figures 2 and 3 are the first
The postcards have the same functions as in the figure, and the postcards in FIGS. 5 and 6 have the same functions as in FIG. 4, and the ones in FIGS. 8, 9, and 10 have the same functions as in FIG. 7. a... Sheet before joining b... Confidentiality postcard C... Strong adhesive layer area d... Weak adhesive layer area e... Information f... Folding sewing machine Eye g...perforation for cutting h...adhesive layer area i...window j...non-joint part k...joint part

Claims (4)

[Claims] (1) In a confidential postcard in which sheets having an adhesive layer on at least a portion of the base material are bonded together under pressure, the entire or part of the edge portion of the bonded portion of the postcard is bonded to each other by the adhesive layer, and the non-edge A confidential postcard characterized in that the parts are joined by a layer of adhesive. (2) The confidential postcard according to claim (1), wherein the entire or part of the edge portion of the joint of the postcard is non-peelable. (3) Claim in which the sheet is paper with a resin layer provided on the surface (
Confidentiality postcard described in 1) or (2). (4) Claim (1) in which the sheets to be joined are connected to each other
) to (3) confidentiality postcard.