JP3476388B2 - Cold seal adhesive - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold seal adhesive which can be adhered by applying a certain pressure or more, but the adhesion can be released by an appropriate force. After coating and drying on the printed surface, information is printed and ink-jet recorded, or after information is printed on the printed surface of the paper, coated and dried, ink-jet recorded, and then those recorded surfaces are recorded. Cold seal adhesive for press-bonding with the coated surface to make it removable again. In addition to inkjet recording using black ink, inks of various colors such as red, blue and green are used. The present invention relates to a cold seal adhesive that can be used for color (or full color) ink jet recording.

[0002]

2. Description of the Related Art In recent years, banks, credit companies, insurance companies, government agencies, etc. have addressed individual individuals to their savings status, balance information,
A so-called confidential postcard is used as a means of notifying specific information such as insurance contract status and pension information. The paper used for such confidential postcards is usually coated beforehand with an adhesive called cold seal adhesive before recording the information. Next, after printing the common information about the confidential postcards by using a method such as offset printing or gravure printing, specific individual information such as each personal information is recorded. The order of printing and coating may be mixed. Furthermore, the information-printed surface of the confidential postcard can be adhered by superimposing it on the other coated surface and applying a predetermined pressure or more. The adhesion of the cold seal adhesive can be released by peeling it off with an appropriate force, that is, the cold seal adhesive is configured to exhibit remarkable removability. It is said that if the pressure applied is low at the time of bonding with the cold seal adhesive, the bonding cannot be performed and thus the confidentiality is maintained.

Such a cold seal adhesive and its removability are disclosed, for example, in JP-A-5-295335. Here, in this specification, "printing"
The term means to write common information, a pattern, etc. by using any general printing method such as offset printing or gravure printing. The term “recording or inkjet recording” means using a so-called inkjet printer. Printing of information, patterns, and the like means, for example, writing individual information and the like.

Further, the "ink jet recording" includes various chromatic colors such as red, blue, yellow and green in addition to ink jet recording using achromatic inks such as black and gray having various lightness. Inkjet recording using ink is also included. The chromatic color includes colors having various hues, lightnesses, and saturations. In addition, in "ink jet recording",
For example, metallic colors such as gold, silver and chrome are also included. Therefore, in this specification, "color (or full color)" refers to all of these colors, that is, achromatic color, chromatic color, and metallic color.

Conventionally, a laser beam type printer has been mainly used as a method for recording specific information such as personal information on the confidential postcard. On the other hand, in recent years, inkjet printers that use water-soluble dyes have come to be used because of high processing speed and the ability to handle recording in small lots. However, if a cold seal adhesive compatible with a conventional laser beam printer (hereinafter referred to as "conventional cold seal adhesive") is used as it is in an inkjet printer, a problem may occur in print quality. I understand. That is, when water adheres to the printing portion, the water-soluble dye (hereinafter, referred to as “aqueous dye”) of the inkjet printer is eluted in water,
With the problem of water resistance that information is difficult to read,
When the information surface is peeled off after the printing surface is pressure-bonded, there arises a transferability problem that the printing is transferred to the opposite surface.

The above-mentioned problems result from the difficulty of fixing the printed water-based dye to the conventional cold seal adhesive. Usually, an aqueous dye has a salt of a sulfo group and / or a carboxyl group in its dye molecule, and is made water-soluble by the salt. Therefore, the dye of the aqueous dye contains anionic molecules that are negatively charged. On the other hand, the conventional cold seal adhesive is also an anionic dispersion system, and its adhesive component is negatively charged. For example, natural rubber, modified natural rubber, synthetic rubber, etc. can be illustrated. Therefore, since the water-based dye and the adhesive component of the conventional cold seal adhesive are both negatively charged and do not attract electrically, it is considered that the water-based dye is difficult to be fixed to the conventional cold seal adhesive.

By the way, as a printing paper for an ink jet printer, a special paper is used to impart water resistance to the water-based dye. That is, the positively charged cationic polymer is introduced into the ink receiving layer of the printing paper. In this method, a dye molecule having a negative charge is captured by the positive charge of the cationic polymer, and the dye molecule is fixed to the ink receiving layer by Coulomb force by evaporation of water. Examples of the cationic polymer introduced into the ink receiving layer include quaternized polyvinyl pyridine, polyethylene imine, quaternized polyethylene imine,
Polyallyl sulfone, dicyandiamide condensate, polyethylene polyamine-based polymer, polyallylamine, polydiallylamine, alkylamine / epichlorohydrin condensate, polyamine / epichlorohydrin-based polymer,
Polyalkylene polyureas, polyamide polyureas, dimethylallylammonium chloride, cationic vinyl copolymers and the like are disclosed (see JP-A-7-315632 and JP-A-8-51487).

Therefore, it was expected that a cold seal adhesive suitable for ink jet recording could be obtained based on the idea that water resistance and non-transferability can be similarly imparted to an aqueous dye. For example, Japanese Patent Laid-Open No. 10-
Japanese Patent No. 52985 discloses a method for obtaining a cold seal adhesive suitable for ink jet recording by adding a cationic polymer, which is usually used in recording paper for ink jet printers, to a conventional cold seal adhesive. ing. However, it is described that although the water resistance and non-transferability of the water-based dye are improved, the viscosity of the cold seal adhesive is largely thixotropic and the characteristics are not always stable. Further, this method also has a problem of offset printing suitability that stains the offset plate during offset printing because the cationic polymer has high water solubility.

Further, Japanese Patent Laid-Open No. 9-71758 discloses a weak cationic polymer capable of maintaining relatively good system stability even when added to a modified natural rubber which is an adhesive component of a conventional cold seal adhesive. Discloses a method of obtaining a cold seal adhesive suitable for ink jet recording by adding it to a conventional cold seal adhesive. However, in this method, since the polymer to be added has a weak cationic property, if the addition amount is small, it is not possible to impart sufficient water resistance and non-transferability to the aqueous dye. Therefore, if the addition amount of the weak cationic polymer is increased, the problem that the adhesive strength is lowered occurs. Therefore, with this method, it is difficult to easily obtain a cold seal adhesive suitable for ink jet recording having a good balance of characteristics.

In fact, the present inventors have also confirmed that when a cationic polymer is added to a conventional cold seal adhesive, the dispersion system of the cold seal adhesive becomes unstable. In addition, increasing the amount of cationic polymer added to conventional cold seal adhesives to improve the water resistance and non-transferability of water-based dyes increases viscosity immediately, or during storage, agglomerates formation and It was also confirmed that gelation or the like occurred and it became impossible to use as a cold seal adhesive.

Therefore, simply by blending a conventional cold seal adhesive with a conventionally used cationic polymer, the water resistance of the water-based dye is improved and the transferability of the print at the time of re-peeling is improved. It can be said that it is difficult to obtain a cold-seal adhesive suitable for inkjet recording, which has a lowering property and a good offset printing suitability.

Further, in recent years, information can be diversified, information can be increased, images are beautiful and easy to see, and full-color fixed format printing, which was conventionally performed by offset printing, is printed by a single machine together with variable information. For reasons such as possible, inkjet recording
In addition to recording using achromatic colors such as black, color inkjet recording using chromatic colors such as red, blue, green and yellow has come to be widely used. However, in the above-mentioned conventional cold seal adhesive, there is no report on the cold seal adhesive used for color ink jet recording. Therefore, there is a demand for a cold seal adhesive suitable for inkjet recording of a color, in which at least one of water resistance and non-transferability of a color water-based dye for inkjet recording is improved, and offset printing suitability is good.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to use a color ink jet printer on a previously coated cold seal adhesive. After recording, even if water adheres to the print part, the water resistance problem that the color water-based dye of the color ink jet printer is eluted in water and when the print surface is pressure-bonded and then peeled off, the print is transferred to the opposite surface. At least one of the problems of transferability of the dye is alleviated, preferably substantially eliminated, and further, the offset printability is good, and these properties can be easily adjusted appropriately. It is to provide a cold seal adhesive having high performance.

Another object of the present invention is to apply a color ink jet method after coating and drying information on a printing surface of a sheet or after printing information on a printing surface of a sheet and coating and drying. After recording with a printer, even if water adheres to the printing part, the water resistance problem that the color water-based dye of the color inkjet printer dissolves in water, and when the printed surface is peeled off after pressure bonding, the opposite surface is printed. At least one of the problems of transferability of the water-based dye to be transferred to is mitigated, preferably substantially eliminated, and further offset printability is good, and these characteristics can be easily adjusted appropriately. To provide a cold seal adhesive with high overall performance.

[0015]

According to one aspect of the invention, a new adhesive is provided, which comprises at least one selected from natural rubber latex, modified natural rubber latex and synthetic rubber latex. A cold seal adhesive comprising (A) an adhesive component consisting of (B) and (B) an amphoteric polymer, wherein (B) the amphoteric polymer is (C) a polymerizable anionic monomer: 2-30 % By weight, and (D)
Cold ink for color ink jet recording, characterized in that it is a copolymer of a monomer mixture containing 50 to 98% by weight of dimethylaminoethylbenzyl methacrylic acid (meth) acrylate as a polymerizable cationic monomer. It is a seal adhesive. This is especially because after the adhesive is applied to the printed surface of the paper or the surface of the non-printed paper and dried, information etc. is recorded, and this recorded surface is integrated with other coated surfaces. It is suitable as a cold seal adhesive for color ink jet recording which is pressure-bonded to be removable. In the description of the present specification, unless otherwise specified, a solvent-free (dry) state is used as a reference for parts by weight and% by weight.

Further, according to one aspect of the present invention, the new adhesive is applied to the printing surface (that is, the surface to be printed) of the paper, and the information is printed after drying. It is suitable for a cold seal adhesive for forming a removable paper by press-bonding the surface after color ink jet recording integrally with the surface after other coating. The paper may be printed and / or recorded before coating. In addition, according to another aspect of the present invention, a new adhesive is provided, which particularly applies the adhesive after printing the information on the printing side (ie, the side to be printed) of the paper. It is suitable for a cold seal adhesive for drying and drying, and the surface after color ink jet recording is pressed integrally with the surface after other coating to form a removable paper.

In the present invention, the term "other surface after coating" means any other surface (usually the surface of paper) on which the cold seal adhesive of the present invention has been applied and dried. Also, for example, such a surface may be printed before coating, or may be printed after coating, and may be recorded before coating, or after coating. It may be recorded. Specifically, it refers to coating → printing → recording, coating → recording, coating → printing, printing → coating → recording, printing → coating, or a surface treated only by coating. This "other coated surface" may be a part of the paper coated with the adhesive or may be another paper coated with the adhesive.

The "compression bonding" is similar to the processing conventionally used for cold sealing, and two surfaces coated with an adhesive are overlapped with each other so that they are in contact with each other, and pressure and, if necessary, heat are applied to the two surfaces. This refers to bonding the surfaces together. As a result, the information that is temporarily adhered and recorded can be hidden. The pressure used may be that normally used, and specifically, for example, a linear pressure of 100 kg / cm may be used. Further, "removable" means that the two surfaces, which are integrally adhered to each other to conceal information as described above, can be easily separated by hand so that the recorded information or the like can be identified. What enables such pressure bonding and re-peeling is called a cold seal adhesive.

In the present invention, "(A) adhesive component" means
A component which is a main component of the adhesive force and which has at least one selected from natural rubber latex, modified natural rubber latex and synthetic rubber latex, has self-adhesiveness, and is a conventional cold seal adhesive as (A). What is used as the adhesive component of the agent can be used.
Specific examples of such (A) adhesive component include those disclosed in JP-A-5-295335, JP-A-5-186640, JP-A-9-310055, and the like. Select appropriately according to the characteristics to be
It can be used as (A) of the present invention. Note that the contents of these specifications are the contents of the present specification by this citation.

The term "natural rubber latex" as used herein means an emulsion of naturally occurring rubber. Further, the "modified natural rubber latex" is a natural rubber latex obtained by copolymerizing a natural rubber latex with a polymerizable monomer to modify its characteristics, for example, a natural rubber latex,
Examples thereof include natural rubber latex modified by copolymerization with various unsaturated monomers such as (meth) acrylic acid alkyl esters and styrene. Specifically, (meth) acrylic acid alkyl ester is copolymerized. The natural rubber latex modified with acrylic acid can be exemplified (see JP-A-5-295335). (In the present specification, acrylic acid and methacrylic acid are collectively referred to as “(meth) acrylic acid”.) The modified natural rubber latex has a desired property.
The type of monomer to be copolymerized and the amount to be copolymerized can be appropriately selected.

Furthermore, "synthetic rubber latex" refers to an emulsion of synthetic rubber, for example, styrene-butadiene rubber (SBR) latex, nitrile-butadiene rubber (NBR) latex, methyl methacrylate-butadiene rubber (MBR) latex. , Synthetic rubber latex such as neoprene latex can be exemplified (see JP-A-5-186640). When the cold seal adhesive of the present invention comprises (A) a modified natural rubber latex and a synthetic rubber latex as an adhesive component, the modified natural rubber latex is added to 100 parts by weight of the modified natural rubber latex.
The synthetic rubber latex is preferably contained in an amount of 5 to 30 parts by weight, more preferably 10 to 25 parts by weight.

In the present invention, "(B) amphoteric polymer"
Is an anion group and an anion group in one polymer
At least one functional group array selected from the functional groups to be obtained
Dimethylaminoethyl benzyl (meth) acrylate
Loride [(CH₂= C (CH₃) COOCH₂CH₂N
(CH₃)₂-CH₂C₆H_Five)⁺Cl^-] Derived from
2- (N, N-dimethyl-N-benzylan)
Monium) ethyl group [-CH₂CH₂-N⁺(CH₃)₂−
CH₂C₆H_Five], Which is a polymer comprising (C) polymerization
Anionic monomer and (D) polymerizable cationic monomer
Dimethylaminoethyl acrylate (meth) acrylate
Copolymerize a monomer mixture containing benzyl chloride
Can be obtained by In the present invention,
Is dimethylaminoethylbenzyl (meth) acrylate
Chloride of chloride^-)instead of
In addition, acetate (acetate: CH₃COO^-), Bromai
De (bromide: Br^-) And iodide:
I ^-) Can be used.

The term "(C) polymerizable anionic monomer" as used herein includes at least one functional group selected from an anion group and a functional group capable of forming an anion group, and a polymerizable functional group. The "functional group capable of forming an anion group" refers to a functional group that reacts with a base or the like to form an anion group, and examples thereof include a carboxyl group, a sulfo group, a phosphoric acid group, and the like. "Group" means, for example,
Examples thereof include carboxylates, sulfonates and phosphates. The "compound comprising at least one functional group selected from an anion group and a functional group capable of forming an anion group and a polymerizable functional group" is, for example, (C1) acrylic acid, methacrylic acid, itaconic acid, fumar Monomers having carboxyl group and ethylenic double bond such as acid, maleic acid and maleic acid half ester and salts thereof: (C2) Monomer having sulfo group such as styrenesulfonic acid and ethylenic double bond Body and salts thereof: (C3) (meth) acrylic acid oxyethylamide phosphate and the like can be exemplified. The counter cation of the salts is preferably ammonium ion, alkali metal ion or the like, particularly preferably ammonium ion, potassium ion or sodium ion. In particular, acrylic acid and methacrylic acid are preferable as the (C) polymerizable anionic monomer. These anionic monomers can be appropriately used alone or in combination depending on the characteristics of the target amphoteric polymer.

The monomer mixture for obtaining the (B) amphoteric polymer by copolymerization preferably contains 2 to 30% by weight, and preferably 2 to 15% by weight, of the (C) polymerizable anionic monomer. Is more preferable. Further, the monomer mixture preferably contains (D) dimethylaminoethylbenzyl chloride (meth) acrylate, which is a polymerizable cationic monomer, in an amount of 50 to 98% by weight, and preferably 70 to 98% by weight. More preferable.

The anionic group of the polymerizable anionic monomer (C) contained in the monomer mixture and the functional group capable of forming the anionic group, and (D) the polymerizable cationic monomer (meth) acryl. The molar ratio of the cation groups of the acid dimethylaminoethylbenzyl chloride (anion group and functional groups capable of forming anion groups / cation groups) is 10/90 to 30.
/ 70 is preferable.

Further, the monomer mixture preferably contains (E) a water-soluble and nonionic polymerizable monomer. Here, the term “(E) water-soluble and nonionic polymerizable monomer” means (B) to improve the water dispersibility of the amphoteric polymer.
A monomer capable of imparting hydrophilicity to, and having substantially no ionic property, for example, (E1) (meth) acrylamide, methylol (meth)
(Meth) acrylic acid amides such as acrylamide: (E2) hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, etc. (meth) acrylic acid hydroxyalkyl esters: (E3) polyoxyalkylene (meth ) Acrylates and the like can be exemplified. (E) can be used alone or in combination.

The monomer mixture for obtaining the (B) amphoteric polymer by copolymerization preferably contains 1 to 20% by weight of the (E) water-soluble and nonionic polymerizable monomer, and 3-1.
It is more preferable to contain 0% by weight. By using (E), the water dispersibility of the (B) amphoteric polymer can be improved, so that (B) can be more stably compounded in the cold seal adhesive.

Further, in the present invention, the monomer mixture may contain other polymerizable monomers. Here, "other polymerizable monomers" are (C) polymerizable cationic monomers and (D) polymerizable anionic monomers (meth) acrylic acid dimethylaminoethyl benzyl chloride. A compound comprising a functional group copolymerizable with
(E) refers to monomers excluding water-soluble and nonionic polymerizable monomers, and examples thereof include (M1) methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and (meth) ) Butyl acrylate, hexyl (meth) acrylate, (meth)
(Meth) acrylic acid alkyl esters such as octyl acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, and dodecyl (meth) acrylate: (M2) Epoxy groups such as glycidyl (meth) acrylate (Meth) acrylic acid esters having: (M3) Aromatic ethylenic monomers such as styrene and vinyltoluene: (M4) Diene such as ethylene, butadiene and isoprene: (M5) Vinyl acetate, propionic acid Vinyl monomers such as vinyl: (M6) Chlorinated vinyl monomers such as vinyl chloride and vinylene chloride: (M7) Ethylenic monomers having a cyano group such as acrylonitrile. . These other polymerizable monomers can be used alone or in combination.

The amphoteric polymer (B) can be produced by copolymerizing the above-mentioned monomer mixture using a usual polymerization method and an appropriate catalyst. The polymerization reaction may be carried out in an aqueous solvent, or the solvent may be converted to an aqueous solvent after the copolymerization is carried out in an organic solvent. The conditions of the polymerization reaction such as reaction temperature, reaction time, type of solvent, type and concentration of monomer mixture, stirring speed, type and concentration of catalyst can be appropriately selected depending on the characteristics of the target amphoteric polymer and the like. It is a thing.

Here, the "catalyst" is a compound capable of causing a polymerization reaction of a monomer mixture by addition in a small amount, and preferably a compound which can be used in an aqueous solvent and an organic solvent. For example, ammonium persulfate,
Sodium persulfate, potassium persulfate, t-butyl hydroperoxide, t-butyl peroxybenzoate,
2,2-azobisisobutyronitrile (AIBN),
2,2-azobis (2-diaminopropane) hydrochloride, 2,2-azobis (2,4-dimethylvaleronitrile) and the like can be exemplified, and particularly 2,2-azobisisobutyronitrile (AIBN). ), 2,2-azobis (2-diaminopropane) hydrochloride are preferred.

In the present invention, the "aqueous solvent" means
Although it is mainly water such as distilled water and ion-exchanged water, a water-soluble organic solvent such as acetone or lower alcohol may be appropriately added to water for use. Further, in the present invention, the "organic solvent" is not particularly limited as long as it does not substantially adversely affect the polymerization reaction and the properties as an adhesive, and for example, methanol, ethanol, propanol, butanol, ethyl acetate, etc. And combinations thereof can be exemplified.

(B) The molecular weight of the amphoteric polymer is 1,000 or less when the weight average molecular weight is 5000 or less.
When the polymer has a high molecular weight of 000 or more, it is not preferable because of its properties as an adhesive. Furthermore, in the present invention, (B)
The electrical characteristics of the above, that is, the strength of positive and negative charges, the total charge, etc., can be easily adjusted by appropriately selecting the composition of the monomer mixture for polymerization reaction into a preferable combination. It is easy to adjust the water resistance and non-transfer property according to the type, and it is possible to easily provide a cold seal adhesive that appropriately corresponds to the type of color water-based dye.

The cold seal adhesive of the present invention preferably comprises 10 to 120 parts by weight of the (B) amphoteric polymer with respect to 100 parts by weight of the adhesive component (A),
More preferably, it comprises 20 to 100 parts by weight, 30
It is particularly preferred that it comprises ˜90 parts by weight.

The cold seal adhesive of the present invention has an average particle size of 10 microns or less and an oil absorption of 100 ml / 100.
It can comprise more than g of (F) amorphous silica. Here, the “(F) amorphous silica” has a function capable of imparting the property of taking ink into the adhesive layer formed by the cold seal adhesive. (F)
Preferably has an average particle size of 10 microns or less. Furthermore,
The oil absorption of (F) is preferably 100 ml / 100 g or more, more preferably 200 ml / 100 g or more. These (F) amorphous silicas can be used alone or in combination. The cold seal adhesive of the present invention is
It is preferable that 40 to 200 parts by weight of (F) amorphous silica is contained with respect to 100 parts by weight of the adhesive component (A).
More preferably, it comprises from 5 to 175 parts by weight, and from 90 to
It is particularly preferred that it comprises 130 parts by weight.

The cold seal adhesive of the present invention may comprise a particulate filler. Here, the "fine particle filler" is a fine particle filler usually used in cold seal adhesives, and includes, for example, mica, calcium carbonate, kaolin, talc, diatomaceous earth, urea resin, styrene beads, calcined clay. , Grain starch, modified starch, and the like. Further, the fine particle filler is usually particles,
It is preferably spherical, and its size (diameter in the case of spherical shape) is not particularly limited as long as the intended performance of the present invention is exhibited. These fine particle fillers may be used alone or in combination and appropriately selected and used according to the required characteristics. Adhesiveness, blocking resistance, printability, abrasion resistance required as a cold seal adhesive. The properties such as adhesion to paper can be easily and suitably adjusted.

Further, the cold seal adhesive of the present invention may comprise an auxiliary agent. Here, the "auxiliary agent" is an auxiliary agent that is usually used in cold seal adhesives, and it imparts blocking resistance, printability, abrasion resistance, adhesion to paper, etc. Examples thereof include water-soluble resins such as polyvinyl alcohol (PVA), starch, polystyrene maleic acid, and carboxymethyl cellulose, synthetic rubbers such as SBR and NBR, acrylic emulsions, and polyolefin emulsions.

The cold seal adhesive of the present invention is in the form of an aqueous emulsion, in which modified natural rubber latex and synthetic rubber latex of the adhesive component and amphoteric polymer are dispersed in an aqueous medium. is doing. In order to maintain this form and develop appropriate adhesive properties,
It can be produced by adding an aqueous solvent as appropriate, stored, and used.

Furthermore, the cold seal adhesive of the present invention may comprise a cationic polymer. In the cold seal adhesive of the present invention, the aqueous dye is provided with water resistance and non-transferability by blending the amphoteric polymer as described above. By adding a small amount of a cationic polymer to the cold seal adhesive for inkjet recording, the water resistance and non-transfer strength of the water-based dye can be easily adjusted. We can make every effort to ensure sex.

The term "cationic polymer" as used herein means a polymer having a positive charge, as long as the addition of a small amount thereof does not adversely affect the adhesive properties of the cold seal adhesive. The cationic strength is not particularly limited, and examples thereof include polydimethylamine ammonia epichlorohydrin, polydimethylamine ethylenediamine epichlorohydrin and the like (see JP-A-10-52985), diallyldimethylammonium chloride, polyamide / epoxy resin, Polyamide / urea resin, aldehyde resin, melanin resin, etc. (JP-A-9-7175)
No. 8) can be exemplified. In particular, polydimethylamine ammonia epichlorohydrin, diallyl dimethyl ammonia chloride and the like can be preferably used. These cationic polymers can be used alone or in combination.

Various additives may be added to the cold seal adhesive of the present invention. Here, the "additive" is an additive that is usually used in a cold seal adhesive if necessary, and examples thereof include a lubricant, a printability improver, an antioxidant, an ultraviolet absorber, a conductive agent, a fluorescent paint, and a coloring agent. Examples thereof include dyes, stabilizers, defoamers, antifungal agents, antibacterial agents, thickeners and moisturizers. Furthermore, in the present invention, in order to enhance the blocking resistance of the cold seal adhesive, a polyethylene dispersion liquid as an additive and / or a tackifier such as a rosin can be added in order to impart adhesive properties. . These additives may be used alone or in combination and appropriately selected and used according to the required properties, and it is possible to provide a cold seal adhesive having excellent printability, stability, mold resistance and the like. .

The cold seal adhesive according to the present invention can be suitably used especially for a confidential postcard, but in addition to this, a confidential envelope,
The information hiding paper, the folding adhesive paper, the overlay adhesive paper, and the like having confidentiality can also be preferably used.

[0042]

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples. However, these examples and comparative examples are merely one aspect of the present invention, and the present invention is not limited by these examples. It is not something that will be done. In the description of the examples, unless otherwise specified, the state of not containing a solvent is used as a reference for parts by weight and% by weight.

(A) to (F) used to prepare the cold seal adhesives of Examples and Comparative Examples are shown below.
(A1) and (a2) are (A) adhesive components,
(A1) is a methyl methacrylate-modified natural rubber latex obtained by copolymerizing natural rubber latex with methyl methacrylate. (A2) is SBR latex.
(B1) to (b6) are (B) an amphoteric polymer,
(B1) to (b6) are all amphoteric polymers obtained by copolymerizing a monomer mixture containing (d1) dimethylaminoethyl methacrylic acid benzyl chloride as a polymerizable cationic monomer. (B1) to (b6) will be described in detail in Examples. (C1) is (C) acrylic acid which is a polymerizable anionic monomer. (D1) is (D) a polymerizable cationic monomer, which is dimethylaminoethyl benzyl methacrylate. (E1) is
(E) Water-soluble and nonionic polymerizable monomer acrylamide. (F1) to (f3) are (F) having an average particle size of 10 microns or less and an oil absorption of 100 ml / 100 g.
The above amorphous silica (f1) has an average particle size of 2.0 to 2.5 microns and an oil absorption of 250 ml / 10.
It is an amorphous silica having a specific surface area of 0 g or more and a specific surface area of 300 m ² / g. (F2) has an average particle size of 0.7 to 2.0 microns, an oil absorption of 130 ml / 100 g or more, and a specific surface area of 25.
It is 0 m ² / g of amorphous silica. (F3) has an average particle size of 5.0 to 10.0 microns and an oil absorption of 240 ml
/ 100 g or more and a specific surface area of 190 m ² / g, which is an amorphous silica.

Example 14 (c1) acrylic acid by weight,
96 parts by weight of (d1) dimethylaminoethyl methacrylic acid benzyl chloride [(CH ₂ ═C (CH ₃ ) COOC
_{H 2 CH 2 N (CH 3} ) 2 -CH 2 C 6 H 5) + Cl -] 90
Add 0 parts by weight of distilled water and stir 1 parts by weight of 2,2
After adding -azobis (2-diaminopropane) hydrochloride, the mixture was heated to 80 ° C and reacted for 3 hours (b
1) An amphoteric polymer was synthesized.

On the other hand, 15 parts by weight of (a2) SBR latex, relative to 100 parts by weight of (a1) methyl methacrylate-modified natural rubber latex obtained by copolymerizing natural rubber latex with methyl methacrylate by a conventional method, 6
0 part by weight of the above-mentioned (b1) amphoteric polymer, 100 parts by weight of (f1) amorphous silica (average particle size 2.0 to 2.5 microns, oil absorption 250 ml / 100 g, specific surface area 3
00 m ² / g), 30 parts by weight of a fine particle filler composed of starch, and 30 parts by weight of an auxiliary agent were mixed to obtain a cold seal adhesive of Example 1.

The dispersion stability of this cold seal adhesive is determined by the grit value of the adhesive (whether or not aggregates are generated when the cold seal adhesive is compounded), the change in viscosity of the cold seal adhesive, and the cold seal adhesive. Was evaluated by visual observation. The viscosity was measured using a B-type viscometer (30 ° C.). The occurrence of grit was not observed, there was substantially no increase in viscosity, and the aggregate could not be visually observed. ○, the occurrence of grit was not observed, and even if the aggregate could not be visually observed, the viscosity was The increased amount was evaluated as Δ, and the occurrence of grit was recognized, and the increased viscosity and gelation were evaluated as x. The results are shown in Table 1.

Evaluation Method of Cold Seal Adhesive (1) Preparation of Test Paper The cold seal adhesive was coated on one side of a support sheet made of high quality paper (130 g / m ² ) with a coating amount of 10 g after drying.
It was coated so as to be / m ² and dried to obtain an adhesive agent-coated sheet. This adhesive coated sheet was printed with a black ink, red ink, blue ink and green ink manufactured by Cytex Co., using an inkjet printer to obtain a test paper.

(2) Evaluation of Water Resistance of Aqueous Dye The water resistance of the aqueous dye was evaluated 5 minutes after printing on the coated sheet, and the printed portion of the test paper was dipped in water for 3 minutes, and then printed. It was carried out by visually observing the presence or absence of bleeding and elution of the aqueous dye in water and the overall appearance of printing after the test paper was taken out of the water. The case where the printing on the test paper did not change at all as compared with that before immersion in water was evaluated as ◯, the case where it was slightly changed but not noticeable was evaluated as Δ, and the case where even a slight noticeable change was caused was evaluated as x. The results are shown in Table 1. In all of the examples and comparative examples, there was no difference in the results due to the difference in color type.

(3) Evaluation of Non-Transferability of Aqueous Dye The non-transferability of the aqueous dye was evaluated by testing the test paper 5 minutes after printing on the coating sheet at 100 kg / at a temperature of 20 ° C. and a humidity of 60%. It was carried out by visually observing the presence or absence of the transfer of the aqueous dye when pressing with a linear pressure of cm and repeeling after 30 minutes. When the test paper was not printed at all, it was marked with ◯, when it was slightly transferred but not noticeable, it was marked with Δ, and when even a little noticeable transfer was generated, it was marked with x. The results are shown in Table 1. In all of the examples and comparative examples, there was no difference in the results due to the difference in color type.

(4) Evaluation of Blocking Resistance Regarding the evaluation of blocking resistance, the coated surfaces of the coated sheet were brought into close contact with each other, a pressure of 10 kg / cm ² was applied, and then the temperature was 20 ° C. and the humidity was 60%. It was evaluated by visually observing the state after standing for 24 hours. Those that were not adhered at all were evaluated as ◯, those that were slightly adhered were evaluated as Δ, and those that were adhered were evaluated as x. The results are shown in Table 1.
In all of the examples and comparative examples, there was no difference in the results due to the difference in color type.

Example 2 Instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethylbenzyl methacrylic acid chloride in Example 1, 8 parts by weight of (c1) were used.
And 92 parts by weight of (d1) were used to obtain (b2) an amphoteric polymer, and (b1) was used in place of the (b2) amphoteric polymer. A cold seal adhesive was obtained. In the same manner as in the method described in Example 1, the dispersion stability of the cold seal adhesive of Example 2 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 1.

Example 3 In place of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethylbenzyl methacrylic acid chloride in Example 1, 12 parts by weight of (c1) were used.
Example 1 was repeated in the same manner as in Example 1 except that 1) and 88 parts by weight of (d1) were used to obtain (b3) an amphoteric polymer, and (b1) was replaced with (b3). A cold seal adhesive of 3 was obtained. The dispersion stability of the cold seal adhesive of Example 3 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 4 Instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylate chloride in Example 1, 7 parts by weight of (c1) was used.
1), 92 parts by weight of (d1) and 1 part by weight of (e1) acrylamide to obtain (b4) an amphoteric polymer,
1) A cold seal adhesive of Example 4 was obtained in the same manner as in Example 1 except that (b4) was used instead of the amphoteric polymer. The dispersion stability of the cold seal adhesive of Example 4 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 5 Instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylic acid chloride in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) an amphoteric polymer,
1) A cold seal adhesive of Example 5 was obtained in the same manner as in Example 1 except that (b5) was used instead of the amphoteric polymer. The dispersion stability of the cold seal adhesive of Example 5 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 6 Instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylic acid chloride in Example 1, 7 parts by weight of (c1) was used.
1), 86 parts by weight of (d1) and 7 parts by weight of (e1) acrylamide were used to obtain (b6) an amphoteric polymer, (b6)
1) A cold seal adhesive of Example 6 was obtained in the same manner as in Example 1 except that (b6) was used instead of the amphoteric polymer. Similarly to the method described in Example 1, the dispersion stability of the cold seal adhesive of Example 6 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 1.

Example 7 Instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylate (d1) in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) amphoteric polymer, and instead of 60 parts by weight of (b1) amphoteric polymer, 20 parts by weight of (b).
Example 7 was carried out in the same manner as in Example 1 except that 5) was used.
To obtain a cold seal adhesive. The dispersion stability of the cold seal adhesive of Example 7 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 8 Instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylic acid chloride in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) amphoteric polymer, and instead of 60 parts by weight of (b1) amphoteric polymer, 40 parts by weight of (b1).
Example 8 was conducted in the same manner as in Example 1 except that 5) was used.
To obtain a cold seal adhesive. Similar to the method described in Example 1, the dispersion stability of the cold seal adhesive of Example 8 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 1.

[0058]

[Table 1]

Example 9 In place of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylate, in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) an amphoteric polymer,
1) (b5) was used instead of the amphoteric polymer, and further 100
A cold seal adhesive of Example 9 was obtained in the same manner as in Example 1, except that 150 parts by weight of (f1) was used in place of the parts by weight of (f1) amorphous silica. Similarly to the method described in Example 1, the dispersion stability of the cold seal adhesive of Example 9 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 2.

Example 10 Instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylic acid chloride in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) an amphoteric polymer,
1) (b5) was used instead of the amphoteric polymer, and further 100
A cold seal adhesive of Example 10 was obtained in the same manner as in Example 1, except that 50 parts by weight of (f1) was used instead of 50 parts by weight of (f1) amorphous silica. The dispersion stability of the cold seal adhesive of Example 10 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated in the same manner as in Example 1. The results are shown in Table 2.

Example 11 In place of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethylbenzyl methacrylic acid methacrylate in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) an amphoteric polymer,
1) (b5) was used instead of the amphoteric polymer, and further 100
Instead of 50 parts by weight of (f1) amorphous silica, 50 parts by weight of (f1) and 50 parts by weight of (f2) amorphous silica (average particle size 0.7-2.0 microns, oil absorption 130 ml)
/ 100 g, specific surface area of 250 m ² / g) was obtained in the same manner as in Example 1 to obtain a cold seal adhesive of Example 11. Dispersion stability of the cold seal adhesive of Example 11, as in the method described in Example 1,
The water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 2.

Example 12 Instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylate chloride in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) an amphoteric polymer,
1) (b5) was used instead of the amphoteric polymer, and further 100
Instead of 50 parts by weight of (f1) amorphous silica, 50 parts by weight of (f2) amorphous silica and 50 parts by weight of (f3) amorphous silica (having an average particle size of 5.0 to 10.0 microns, Oil absorption 240ml / 100g, specific surface area 190m ² /
Example 1 was repeated in the same manner as in Example 1 except that g) was used.
A cold seal adhesive of 2 was obtained. Similarly to the method described in Example 1, the dispersion stability of the cold seal adhesive of Example 12 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 2.

Example 13 In Example 1, instead of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethylbenzyl methacrylic acid chloride, 7 parts by weight of (c1)
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) an amphoteric polymer,
1) Use (b5) instead of the amphoteric polymer, and
1) A cold seal adhesive of Example 13 was obtained in the same manner as in Example 1 except that (f2) amorphous silica was used instead of amorphous silica. Similarly to the method described in Example 1, the dispersion stability of the cold seal adhesive of Example 13 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 2.

Example 14 In place of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethylbenzyl methacrylic acid chloride in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) an amphoteric polymer,
1) Use (b5) instead of the amphoteric polymer, and (a)
2) A cold seal adhesive of Example 14 was obtained in the same manner as in Example 1 except that SBR latex was not used at all. The dispersion stability of the cold seal adhesive of Example 14 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated in the same manner as in Example 1. The results are shown in Table 2.

Example 15 In place of 4 parts by weight of (c1) acrylic acid and 96 parts by weight of (d1) dimethylaminoethyl benzyl methacrylic acid chloride in Example 1, 7 parts by weight of (c1) was used.
1), 88 parts by weight of (d1) and 5 parts by weight of (e1) acrylamide were used to obtain (b5) an amphoteric polymer,
1) In the same manner as in Example 1 except that (b5) was used in place of the amphoteric polymer, and 30 parts by weight of (a2) was used in place of 15 parts by weight of (a2) SBR latex.
The cold seal adhesive of Example 15 was obtained. Similarly to the method described in Example 1, the dispersion stability of the cold seal adhesive of Example 15 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 2.

[0066]

[Table 2]

Comparative Example 1 A cold seal adhesive of Comparative Example 1 was obtained in the same manner as in Example 1 except that (b1) the amphoteric polymer was not used at all. Similarly to the method described in Example 1, the dispersion stability of the cold seal adhesive of Comparative Example 1 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated. The results are shown in Table 3.

Comparative Example 2 In Example 1, 10 parts by weight of a cationic polymer (polydimethylamine ammonia epichlorohydrin) was used in place of 60 parts by weight of (b1) amphoteric polymer, and further 100 parts by weight of (f1). 50 instead of amorphous silica
A cold seal adhesive of Comparative Example 2 was obtained in the same manner as in Example 1 except that (f1) in parts by weight was used. Example 1
The dispersion stability of the cold seal adhesive of Comparative Example 2 and the water resistance, non-transferability and blocking resistance of the aqueous dye were evaluated in the same manner as described in 1. The results are shown in Table 3.

[0069]

[Table 3] a) -indicates that the evaluation was impossible.

[0070]

According to the present invention, at least one of the problems of water resistance and non-transferability of a color water-based dye for a color ink jet printer is alleviated, preferably substantially eliminated, and further, the offset printability is excellent, and the dispersion is excellent. It is possible to provide a cold seal adhesive having good stability.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C09J 115/00 C09J 133/02 133/02 133/06 133/06 133/16 133/16 133/26 133/26 141/00 141/00 143/02 143/02 B41J 3/04 101Y (58) Fields investigated (Int.Cl. ⁷ , DB name) C09J 101/00-201/10 B41J 2/01 B41M 5/00 B42D 15/02 501

Claims (8)

(57) [Claims] 1. A comprise natural rubber latex, comprising at least one member selected from modified natural rubber latex and synthetic rubber latex (A) an adhesive component, and the (B) an amphoteric polymer, (B) an amphoteric Polymer is (C) polymerizable anionic monomer: 2 to 30% by weight, and (D) polymerizable cationic monomer (meth) acrylic acid dimethylaminoethylbenzyl chloride: 50 to
It is a copolymer of a monomer mixture comprising 98% by weight.
Adhesion of cold seal for color inkjet recording
Te, (F) amorphous silica (average particle diameter of 10 microns or less,
An oil absorption amount of 100 ml / 100 g or more)
-Cold seal adhesive for inkjet recording. 2. In order to enable re-peeling by printing the information on the printed surface of the paper, printing the information, inkjet recording, and then press-bonding the recorded surface integrally with another coated surface. The cold seal adhesive according to claim 1. 3. To print the information on the printing surface of the paper, coat it and dry it, and after ink jet recording, press the recorded surface integrally with another coated surface to enable re-peeling. The cold seal adhesive according to claim 1. 4. (A) A modified natural rubber latex and a synthetic rubber latex are contained as an adhesive component, and 5 to 30 parts by weight of the synthetic rubber latex is contained with respect to 100 parts by weight of the modified natural rubber latex. The cold seal adhesive according to any one of claims 1 to 3. 5. The cold seal adhesive according to any one of claims 1 to 4, wherein the modified natural rubber latex is a natural rubber latex modified by polymerizing an alkyl (meth) acrylate ester. Agent. 6. The monomer mixture is (E) a water-soluble and nonionic polymerizable monomer: 1 to 20.
%, Further comprising% by weight.
The cold seal adhesive according to any one of 5 above. 7. (A) 100 parts by weight of the adhesive component,
The cold seal adhesive according to any one of claims 1 to 6, which comprises 10 to 120 parts by weight of (B) an amphoteric polymer. 8. (A) 100 parts by weight of the adhesive component,
The cold seal adhesive according to any one of claims 1 to 7, which comprises (F) 40 to 200 parts by weight of amorphous silica.