JPH11301150A - Pressure sensitive pseudo adhesive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a stable adhesive force by providing various information by using an electron beam curable ink on a recording sheet having a pressure sensitive pseudo adhesive performance, thereby eliminating a decrease in the adhesive force by a fixing treatment or the like of the ink by illuminating an electron beam. SOLUTION: Various information is provided in an information layer 4 of a sheet having a pseudo adhesive layer 2 containing an acrylic resin emulsion including an acrylic ester and a water-soluble resin emulsion as main components as a pressure sensitive adhesive by using an electron beam curable ink, and the ink is dried by illuminating an electron beam. Since the electron beam illumination generates small heat, an influence of the heat to a thermosensitive pseudo adhesive sheet is small. In comparison with the case of illuminating an ultraviolet ray, it can be remarkably accelerated, and hence an influence to a pressure sensitive adhesive composition is also small. Accordingly, the pressure sensitive pseudo adhesive sheet printed by this type is satisfactorily print-finished. Further, occurrence of a dirt at the time of printing is eliminated, a deterioration of an adhesive force by illuminating an electron beam is obviated, and a stable adhesive force is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to information recording of a sheet provided with a coating layer having a pseudo-adhesive property which does not adhere under normal conditions but adheres under given conditions and can be easily peeled off when necessary. A pressure-sensitive pseudo-adhesive sheet which is used as a confidential postcard sheet, a superimposed sheet, or a superimposed form paper such as a delivery slip paper, etc. by providing various kinds of information or concealment information using an electron beam curable ink on the surface. It is.

[0002]

2. Description of the Related Art Conventionally, non-peelable adhesives such as natural rubber, synthetic rubber, and acrylic adhesives which do not adhere under normal conditions but adhere under certain conditions and can be easily peeled off when necessary. After printing or printing various information or concealment information on the information recording surface of a sheet provided with a pressure-sensitive adhesive coating layer having a pseudo-adhesive performance based on an adhesive, the coating layers are opposed to each other and a predetermined pressure is applied. , A pressure-sensitive pseudo-adhesive sheet that can be removably adhered has been practically used and used mainly as confidential postcard paper, superimposed sheet, or superimposed form paper such as delivery slip paper. .

[0003] In printing on a pressure-sensitive pseudo-adhesive sheet, when a conventionally used oxidation polymerization type ink is used, the ink is formed by printing on a coating layer of a pressure-sensitive adhesive composition. The ink does not penetrate into the material, and the printing speed is high, which results in poor drying of the ink, blocking of the printed sheet, ink set-off,
The printed surface suffers from adverse effects such as stains and cannot be actually used. Further, when the pressure-sensitive pseudo-adhesive sheets are bonded together at a predetermined pressure, the printed ink is transferred to the opposite surface due to poor drying of the ink, so that the printed information cannot be read.

At present, as a countermeasure, when printing on a pressure-sensitive pseudo-adhesive sheet, an ultraviolet curable ink is used. When printing with UV-curable ink, the sheet is irradiated with UV light from an ultraviolet irradiation device to cure and dry the ink.
There is no adverse effect such as stains on the printing surface, or the problem that the printed ink is transferred to the opposite surface when the pressure-sensitive pseudo-adhesive sheet is bonded at a predetermined pressure.

However, a coating layer of a conventional pressure-sensitive pseudo-adhesive based on a natural rubber, a synthetic rubber, or a non-peelable adhesive such as an acrylic pressure-sensitive adhesive is susceptible to oxidation deterioration by an ultraviolet lamp or the like. . When the adhesive component is deteriorated in this way, the viscoelasticity of the adhesive component becomes poor, and a problem arises in that the adhesive component does not exhibit the required self-adhesiveness or tackiness.

Therefore, when designing the adhesive force of the pressure-sensitive pseudo-adhesive composition, the adhesive force is adjusted in advance so as to express a high adhesive force in consideration of the above-mentioned deterioration of the adhesive force due to ultraviolet rays or the like. However, when these pressure-sensitive pseudo-adhesive sheets are used, the form of use or processing conditions generally varies depending on the user. That is, even if the pressure-sensitive pseudo adhesive sheet is adjusted to the same adhesive strength,
When used only for printing with an offset printing machine, when used only for printing with a non-impact printer, etc., or when used for printing combining both, the degree of adhesive strength deterioration differs depending on each case. Therefore, the adhesive force of the pressure-sensitive pseudo-adhesive sheet during use differs. Therefore, when these pressure-sensitive pseudo-adhesive sheets are pseudo-adhered under the same conditions, the pressure-sensitive pseudo-adhesive sheet is not peeled off due to too low adhesive force or spontaneous peeling during transportation, or the adhesive force is too high to be re-peeled. There were drawbacks such as the occurrence of accidents such as tearing.

When printing these pressure-sensitive pseudo-adhesive sheets, the printing conditions, printing speed, output of ultraviolet lamps, types of ultraviolet lamps, number of ultraviolet lamps, and the like vary from user to user. General. That is, even if the pressure-sensitive pseudo-adhesive sheet is adjusted to the same adhesive force, the degree of deterioration of the adhesive force varies depending on printing conditions, so that the adhesive force of the pressure-sensitive pseudo-adhesive sheet during use differs. come. Therefore, similarly to the above case, when these pressure-sensitive pseudo-adhesive sheets are pseudo-adhered under the same conditions,
There were drawbacks such as spontaneous peeling during transportation due to too low adhesive strength, or accidental breakage of the pressure-sensitive pseudo adhesive sheet without re-peeling due to too high adhesive strength.

Therefore, by providing a protective layer on the coating layer of the pressure-sensitive pseudo-adhesive to adjust the adhesive force and prevent blocking, etc., a removable pressure-sensitive pseudo-adhesive sheet with little deterioration can be obtained. A method has been proposed.

However, the method of providing a protective layer for adjusting the adhesive force of the pressure-sensitive pseudo-adhesive sheet and preventing blocking or the like has disadvantages in that the manufacturing process is complicated and the economy is low.

[0010] Further, when devising a method of folding one sheet, or processing into several superimposed sheets or delivery slips, it is necessary to perform post-processing such as providing a protective layer for each sheet. is there.

Further, when a self-adhesive pressure-sensitive adhesive is used, there is a problem that a material to be bonded must be selected.

[0012]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide various kinds of information and the like using an electron beam-curable ink on the surface of a pressure-sensitive pseudo-adhesive sheet, and to bond the ink by a fixing process or the like by electron beam irradiation. A record that has a stable adhesive force without a drop in force, does not cause blocking after printing, has good printability, has excellent printability, and has a removable pressure-sensitive pseudo-adhesive performance that can be applied to any material. To provide a sheet for use.

[0013]

The inventors of the present invention have conducted intensive studies and as a result, have found that the above-mentioned objects are to provide an acrylic resin emulsion containing an acrylate ester and a water-soluble resin emulsion as main components and a hydrophilic fine particle. Pressure-sensitive adhesive composition characterized by containing as a basic component, and a recording sheet having a pressure-sensitive pseudo-adhesion performance obtained by applying the same, using an electron beam-curable ink to obtain various types of information. Have been found to be achieved by providing

That is, the present invention relates to an information recording surface of a sheet provided with a coating layer having a pseudo-adhesive property which does not adhere in a normal state but adheres under a given condition and can be easily peeled off when necessary. , A pressure-sensitive pseudo-adhesive sheet provided with various information or concealment information using an electron beam-curable ink.

In the present invention, an acrylic resin emulsion containing an acrylic acid ester and a water-soluble resin emulsion as main components is used as the pressure-sensitive adhesive because the water-soluble resin emulsion is dispersed in the acrylic resin ester to form a pressure-sensitive adhesive. In the drying step of the adhesive composition coating layer, the water and the water-soluble resin in the pressure-sensitive adhesive composition move to the surface of the coating layer in accordance with the evaporation, so that the layer containing a large amount of the water-soluble resin component becomes sensitive. Since the pressure-sensitive pseudo-adhesive sheet coated with the pressure-sensitive adhesive composition of the present invention is formed on the surface of the pressure-sensitive adhesive composition coating layer, the pressure-sensitive adhesive sheet prevents blocking or the like, or the pressure-sensitive adhesive coating layer This is for preventing the surface from sticking or preventing the adhesive component from being deteriorated due to the irradiation of the electron beam during printing.

In the present invention, by adding hydrophilic fine particles to the coating layer of the pressure-sensitive adhesive composition, pseudo-adhesive performance capable of re-peeling can be more effectively exhibited.

The adhesion mechanism in this case is not clear, but an adhesion mechanism such as self-diffusion of polymer resin, dipole force, hydrogen bonding, or physical entanglement of polymer resin with paper fiber or the like is used.

The fine particles used in the present invention are preferably hydrophilic and have an average particle diameter in the range of 0.1 to 20 μm. When the average particle size is less than 0.1 μm, fine particles may easily fall off the pressure-sensitive adhesive applied layer, and when the average particle size is 20 μm or more, sufficient adhesive strength may not be exhibited. More preferably, fine particles having an average particle diameter in the range of 1 to 15 μm are preferably used.

The mixing ratio of the water-soluble resin emulsion dispersed in the acrylic resin ester used in the present invention is as follows:
It is preferable that the water-soluble resin emulsion is dispersed in 5 to 200 parts by weight based on 100 parts by weight of the acrylate. If the compounding ratio is less than 5 parts by weight or 200 parts by weight or more, there is a possibility of causing problems such as occurrence of blocking or insufficient development of adhesive strength. Therefore, in the present invention, it is preferable to disperse at least 5 to 200 parts by weight of the water-soluble resin emulsion in the acrylic resin ester. Preferably, an acrylic resin emulsion having a glass transition point in the range of −90 to 50 ° C. is used as an adhesive component in order to develop a suitable adhesive force.

The compounding ratio of the pressure-sensitive adhesive composition used in the present invention is preferably such that 5-200 parts by weight of fine particles are contained with respect to 100 parts by weight of the acrylic resin emulsion. When the compounding ratio is less than 5 parts by weight, the printing or printing suitability is insufficient, or when the compounding ratio is 200 parts by weight or more, the fine particles easily fall off the coated layer of the pressure-sensitive adhesive or the sufficient adhesive force is obtained. There is a risk of adverse effects such as not being expressed. Therefore, in the present invention, it is preferable to use at least 5 to 200 parts by weight of fine particles in the pressure-sensitive adhesive composition. In the present invention, the amount of the pressure-sensitive adhesive composition applied to the substrate is
Normally, ^{2 to 20} g / m ^{2 in} order to develop proper adhesive strength
It is preferable to apply to the extent.

The fine particles used in the pressure-sensitive adhesive composition of the present invention include silica, charcoal, kaolin, clay, talc, aluminum hydroxide, titanium oxide, zinc oxide, activated clay, starch particles, cellulose particles, and styrene. It can be appropriately selected and used from known inorganic or organic fine particles such as resin particles, acrylic resin particles, urea resin particles, microcapsules, oil capsules, polyethylene, and vinyl chloride. These fine particles may be used alone or in combination of two or more.
In the present invention, it is preferred that hydrophilic, more preferably non-thermoplastic, fine particles be contained in the pressure-sensitive adhesive composition.

The water-soluble resin emulsion dispersed in the acrylate ester used in the acrylic resin emulsion used in the pressure-sensitive adhesive composition of the present invention includes polyvinyl alcohol, carboxymethyl cellulose, polyvinyl pyrrolidone, polyacrylic acid, polyacrylamide,
Appropriately selected from known water-soluble polymers such as ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, methyl vinyl ether-maleic anhydride copolymer, and isobutylene-maleic anhydride copolymer. Can be used. These resins may be used alone or in combination of two or more. In the present invention, it is preferable to use a protective colloidized styrene-maleic anhydride copolymer excellent in UV resistance, printability, blocking resistance and the like.

The pressure-sensitive adhesive composition may further contain, if necessary, a surfactant, an antifoaming agent, a thickener, a water-proofing agent, a dispersant,
UV absorbers, antioxidants, antistatic agents, ink fixing agents, dye fixing agents, fluorescent dyes, colored dyes, lubricants, deodorants,
Auxiliary agents such as deodorants and antibacterial agents can be added.

As the base material used in the present invention, for example, high quality paper, medium quality paper, recycled paper, art paper, coated paper, lightly coated paper, synthetic paper, film, laminated paper, metallized paper and the like are used. I can do it.

The application of the pressure-sensitive adhesive composition to the substrate in the present invention can be performed by using a known coating machine such as a blade coater, an air knife coater, a bar coater, a roll coater, a gravure printing machine, a screen printing machine or the like. It can be provided using a machine.

The information to be concealed or various information in the present invention is provided by using an electron beam-curable ink and curing the ink by irradiation with an electron beam.

The electron beam-curable ink comprises a pigment, an oligomer (a prepolymer, a photopolymerizable low polymer), a monomer (a reactive diluent, a photopolymerizable monomer), and other additives. The drying of the ink is performed by polymerizing the ink vehicle by irradiating an electron beam with an electron beam irradiation device incorporated in a printing machine. Further, compared to ultraviolet irradiation, since heat is less generated during electron beam irradiation, the influence of the heat on the pressure-sensitive pseudo-adhesive sheet is also small. In addition, since the speed can be greatly increased as compared with the case of ultraviolet irradiation, the influence on the pressure-sensitive adhesive composition is small.

By printing the pressure-sensitive pseudo-adhesive sheet by this method, the completed pressure-sensitive pseudo-adhesive sheet has a good print quality, does not generate stains at the time of printing, and has a low adhesive strength due to electron beam irradiation. It is possible to obtain a pressure-sensitive pseudo-adhesive sheet having stable adhesive strength without deterioration. Because the pressure-sensitive adhesive coating layer surface is less sticky, it does not cause blocking, etc., and is also excellent in printability. The width increases and the range of application expands. Furthermore, the pressure-sensitive pseudo-adhesive sheet of the present invention can be used for thermal paper, ink-jet paper, thermal transfer paper, or in combination with these papers, or can be coated with an adhesive or the like on the back surface, and can be used for various substrates. It is suitable for use in combination with.

Further, in this printing method, the drying of the ink is accelerated by increasing the irradiation of the electron beam. Therefore, the adhesive force is not deteriorated by the electron beam as compared with the conventional pressure-sensitive pseudo adhesive sheet. Can be many. As a result, the printing speed can be greatly increased, so that printing workability and economic efficiency are excellent.

[0030]

[Embodiment 1] Acrylic ester 100 parts (dry weight), styrene-maleic anhydride copolymer 80 parts (dry weight), and average particle size 7 μm as an adhesive base material
m of synthetic silica (Carplex 80D: manufactured by Shionogi & Co., Ltd.) were mixed to obtain the desired pressure-sensitive adhesive composition. Next, 127.9 g of this pressure-sensitive adhesive composition was used.
/ M ² of high quality paper so that the coating amount was 10 g / m ² (dry weight) to obtain a pressure-sensitive pseudo-adhesive sheet. Printing was performed on the adhesive layer using an electron beam curable ink (Dicure: manufactured by Dainippon Ink and Chemicals, Inc.) using an offset printing machine. Drying of the ink was performed by irradiation with an electron beam from an electron beam irradiation device attached to the printing press. The printing speed was 100 m / min. After 5,000 sheets of sheets subjected to foam processing with this printing machine are left in that state for 24 hours, using a pressure-sensitive pseudo-adhesive sheet provided with this print layer, the adhesive strength, the finish of printing, the blocking property, Table 1 shows the results of evaluating the transfer of the ink after bonding.

Adhesive force: A sample before printing by an offset printing machine was left in an environment of 20 ° C. and 50% RH for 12 hours or more, and then, using a mail sealer (MS-9100: manufactured by Dai Nippon Printing Co., Ltd.) Roll gap 14 (140 μm)
, And a T-type peel test was performed 5 minutes later.

Deterioration test: An electron beam irradiator of an offset printing machine was used to irradiate the sample with an electron beam. The sample was left in an environment of 20 ° C. and 50% RH for 24 hours or more, and the same as the adhesive strength Was evaluated.

Finish of printing: Evaluation was made visually. -Good print finish-Good-Poor print finish-Poor Blocking property: The blocking of the ink was evaluated by peeling the foam paper by hand.・ No blocking → ○ ・ Blocking occurred and stains were observed on the printed surface → × Ink transfer: Transfer the sample to a mail sealer (MS-910).
0: manufactured by Dai Nippon Printing Co., Ltd.)
(140μm), then 20 ° C, 65% R
After leaving for 12 hours under the H condition, the ink was peeled off by hand and the transfer of the ink was visually evaluated. -No ink transfer->-Ink transfer-> Example 2 Acrylic ester 100 as adhesive base material
Parts (dry weight), 40 parts (dry weight) of a styrene-maleic anhydride copolymer, and a synthetic silica having an average particle diameter of 7 μm (Carplex 80D: manufactured by Shionogi & Co., Ltd.)
50 parts were mixed to obtain a target pressure-sensitive pseudo-adhesive composition. The obtained pressure-sensitive adhesive composition was applied to high quality paper in exactly the same manner as in Example 1 to obtain a pressure-sensitive pseudo-adhesive sheet provided with a printing layer using an offset printing machine. Table 1 shows the results of the evaluation of the obtained sheet with respect to adhesive strength, printed finish, blocking property, and transfer of ink after lamination.

Comparative Example 1 100 parts (dry weight) of modified natural rubber latex (Frutite: manufactured by Mitsui Fuller Co., Ltd.) as an adhesive, and synthetic silica 5 having an average particle diameter of 8 μm
0 parts and 50 parts of corn starch were mixed to obtain a desired pressure-sensitive adhesive composition. The obtained pressure-sensitive adhesive composition was applied to high quality paper in exactly the same manner as in Example 1 to obtain a pressure-sensitive pseudo-adhesive sheet provided with a printing layer using an offset printing machine. Table 1 shows the results of the evaluation of the obtained sheet with respect to adhesive strength, printed finish, blocking property, and transfer of ink after lamination.

Comparative Example 2 A pressure-sensitive pseudo-adhesive sheet was obtained in the same manner as in Comparative Example 1 except that the ink was replaced with an oxidation polymerization type ink and printing was performed without performing electron beam irradiation. Table 1 shows the results of the evaluation of the obtained sheet with respect to adhesive strength, printed finish, blocking property, and transfer of ink after lamination.

[0036]

[Table 1]

[0037]

According to the present invention, a sheet provided with a coating layer having a pseudo-adhesive property, which does not adhere under normal conditions but adheres under given conditions and can be easily peeled off when necessary, is made of an electron beam-curable ink. By printing and drying the ink by irradiating with an electron beam, there is no deterioration of the adhesive force, good printing, no blocking or dirt of the ink after printing, A sheet suitable for a pressure-sensitive pseudo-adhesive sheet provided with an information recording surface without causing ink transfer was obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of a pressure-sensitive pseudo-adhesive postcard provided with information using an electron beam-curable ink according to one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA ′ of FIG.

FIG. 3 is a perspective view of an information recording surface of a pseudo pressure-sensitive adhesive sheet before bonding.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Pseudo-adhesive layer, 3 ... Adhesive, 4 ... Information layer.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 31, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0003

[Correction method] Change

[Correction contents]

[0003] When printing on a pressure-sensitive pseudo-adhesive sheet is performed using a conventionally used oxidation polymerization type ink, printing is performed on a coating layer of a pressure-sensitive adhesive composition. good is, the ink does not penetrate the base material, also, because of the fast printing speed, poor drying occurs of the ink, the sheet or cause blocking after printing, you can move back ink,
The printed surface suffers from adverse effects such as stains and cannot be actually used. Further, when the pressure-sensitive pseudo-adhesive sheets are bonded together at a predetermined pressure, the printed ink is transferred to the opposite surface due to poor drying of the ink, so that the printed information cannot be read.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS That is, the present invention relates to a sheet provided with a coating layer having a pseudo-adhesive property which does not adhere under normal conditions but adheres under certain conditions and can be easily peeled off when necessary. A pressure-sensitive pseudo-adhesive sheet in which various information or concealment information is provided on the information recording surface using an electron beam-curable ink.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0030

[Correction method] Change

[Correction contents]

[0030]

[Embodiment 1] Acrylic ester 100 parts (dry weight), styrene-maleic anhydride copolymer 80 parts (dry weight), and average particle size 7 μm as an adhesive base material
m of synthetic silica (Carplex 80D: manufactured by Shionogi & Co., Ltd.) were mixed to obtain the desired pressure-sensitive adhesive composition. Next, 127.9 g of this pressure-sensitive adhesive composition was used.
/ M ² high-quality paper with an application amount of 10 g / m ² (dry weight)
To obtain a pressure-sensitive pseudo-adhesive sheet. Printing was performed on the adhesive layer using an electron beam curable ink (Dicure: manufactured by Dainippon Ink and Chemicals, Inc.) using an offset printing machine. Drying of the ink was performed by irradiation with an electron beam from an electron beam irradiation device attached to the printing press. The printing speed was 100 m / min. After 5,000 sheets of sheets subjected to foam processing with this printing machine are left in that state for 24 hours, using a pressure-sensitive pseudo-adhesive sheet provided with this print layer, the adhesive strength, the finish of printing, the blocking property, Table 1 shows the results of evaluating the transfer of the ink after bonding.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction contents]

Adhesive force: A sample before printing by an offset printing machine was left in an environment of 20 ° C. and 50% RH for 12 hours or more, and then, using a mail sealer (MS - 9100: manufactured by Dai Nippon Printing Co., Ltd.) Roll gap 14 (140 μm)
, And a T-type peel test was performed 5 minutes later.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction contents]

[0036]

[Table 1]

Claims (1)

[Claims] An acrylic resin emulsion containing an acrylic ester and a water-soluble resin emulsion as main components,
A pressure-sensitive pseudo-adhesive sheet comprising a coated layer or a printed layer of the pressure-sensitive adhesive composition, which comprises fine particles as a basic component, provided on a necessary portion or on one or both surfaces of a substrate. A pressure-sensitive pseudo-adhesive sheet characterized in that various information is provided on a necessary portion, one side or the entire surface of the pseudo-adhesive sheet using an electron beam curable ink.