JP2003027023A - Cold seal adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cold seal adhesive improved in at least one of water resistance of ink jet-recorded printed letters, transferring properties and wear resistance of an adhesive layer. SOLUTION: The cold seal adhesive comprises a component (A): at least one selected among natural latices, modified natural latices and synthetic latices, and a component (B): at least one selected from amphoteric polymers, where a specific viscosity (ηsp ), which is represented by the equation (1): ηsp =(η-η<0> )/η<0> , [where η<0> is a viscosity of a 1N NaCl aqueous solution at 30 deg.C; and η is a viscosity of a 10 wt.% aqueous solution of the component (B) in a 1N NaCl aqueous solution as a solvent at 30 deg.C], of a 10 wt.% solution of the component (Bw) in the 1N NaCl aqueous solution as the solvent is 0.5-4.0.

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, that is, an adhesive which, in a normal state, does not cause tack on a coating surface coated with the adhesive. It is an adhesive that does not cause adhesion and blocking even if it is laminated so that the other coated surface and the adhesive layer of both are in contact with each other. The present invention relates to an adhesive that forms a layer of an adhesive that can be adhered to each other by addition and that can be peeled off again after adhesion.

[0002]

2. Description of the Related Art In recent years, various information such as (1) personal information, print information, or confidentiality of print information,
Information that requires confidentiality or concealment, or (2) information that does not necessarily require confidentiality, such as advertisements or advertisements (hereinafter, the information in (1) and (2) is also simply referred to as "information"). The information carrier containing such information is becoming widespread by printing the above.

Here, the term "information carrier" means continuous (for example,
The above "various information" is added to the base sheet of continuous paper wound on a roll) or single sheet (for example, stacked sheets).
Is, for example, a medium of information included by being handwritten or printed, and the medium is, for example, a postcard, an envelope, a business form, a delivery slip, a communication card, a folding card, an overlay sheet, or An information medium in the form of an information concealment sheet or the like. still,
Envelopes and the like are not necessarily printed with information, and should be referred to as information containers for containing information media, but in the present specification, they are included in the above information carrier.

Among such information carriers, a postcard in which a base sheet on which necessary information is recorded is folded with the surface on which the information is recorded inside to give confidentiality (so-called postcard) is a typical one. is there. In the present specification, the “base sheet” refers to a sheet-shaped base material that is usually used for information carriers, and examples of the base sheet include ordinary paper, cloth, and synthetic paper, polyester-based resin, and diester resin. Films of acetate resin, triacetate resin, acrylic resin, polycarbonate resin, polyvinyl chloride resin, polyimide resin, cellophane, celluloid and the like can be used. Further, the "base sheet" includes coated paper or cast coated paper on which a coat layer is provided in advance, and laminated paper in which a resin film is attached to the surface of paper or processed with a molten resin.

The base sheet of such a confidential postcard includes:
Prior to recording information, an adhesive, commonly referred to as a cold seal adhesive, is typically pre-applied. Next, common information about the confidential postcard is printed on the coated surface using a printing method such as offset printing and gravure printing. The order of printing and coating may be mixed. After that, specific individual information such as each personal information is recorded. Further, the printed surface on which the information is printed is overlapped with the other surface coated with the cold seal adhesive so that the adhesive layers on both surfaces are in contact with each other, and a pressure of a certain level or more is applied to bond them. As a result, it is possible to form a laminate in which the confidential information is hidden (not visible from the outside), that is, a confidential postcard. This secret information can be read by peeling off the adhered surface again, but the peeled surface does not adhere unless pressure is applied again more than a certain level, so the secret information is hidden before lamination. Does not return to physical condition. As a result, the confidential postcard can be kept confidential.

By the way, in this specification, "printing" means writing common information and patterns, for example, by using any general printing method such as offset printing and gravure printing. “Inkjet recording” is printing of information and patterns using a so-called inkjet printer, and means, for example, writing information that is not common to each individual. Furthermore, in the present specification, the “adhesive layer” refers to a layer of an adhesive in a solvent-free (dry) state.

The following basic properties are required for such a cold seal adhesive: Under normal conditions, no tack occurs on the coated surface on which the adhesive is applied; under normal conditions, the adhesive is Adhesion and blocking do not occur even if the adhesive layers on the two coated surfaces are laminated so that the adhesive layers contact each other; a certain pressure or more is applied to the overlap between the two layers. Both can be adhered by adding; the adhered surfaces can be peeled again; once peeled, the adhered surfaces are not adhered (in a normal state) unless a certain pressure is applied again.

In the present specification, the "normal state" means that no special operation such as pressurization is applied to a base sheet coated with an adhesive, for example, a cold seal adhesive is used as a base. When the coated surfaces coated on the sheets are stacked and left or stored, when the stacked base sheets are strongly pressed by hand, or when the information is printed on the coated surfaces, a low pressure (about 7, 840 N / m ²
When the following pressure) is applied, etc.

Such cold seal adhesives are additionally required to have the following additional properties: on a layer of adhesive formed by coating the substrate sheet with the adhesive,
Being able to print (hereinafter also referred to as "pre-coating") or capable of forming an adhesive layer by applying an adhesive on the printing of the base sheet (hereinafter also referred to as "post-coating"); It is possible to record specific information such as personal information on the agent layer; adhesion is usually achieved by peeling the base sheets at the adhered parts with a force that is pulled by a person so that they are separated from each other. It is possible to release the information; that is, the information on the surface from which the adhesion has been released can be completely read, that is, the base sheet does not break when the adhesion is released (hereinafter also referred to as "removable").

Conventionally, laser beam printers have been mainly used as a method of recording specific information such as personal information on such confidential postcards. 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 ink jet printer, the quality of ink jet recorded prints will be improved. I've found that a problem occurs. That is, (i) if water adheres to the print part,
Water-soluble dye for inkjet printers (hereinafter,
It is called "water-based dye." ) Elutes in water, making it difficult to read information, and the problem of water resistance in printing.
i) When the ink-jet recorded surface is pressure-bonded and then peeled off, a print transfer problem occurs in that the ink-jet recorded print is transferred to the opposite surface.
In the present specification, "recording, inkjet recording, or recording using an inkjet printer" includes red, blue, green, in addition to recording using an achromatic color such as black.
Full-color recording using chromatic colors such as yellow is also included.

The above problems are caused by the difficulty of fixing the water-based dye contained in the print to the conventional cold seal adhesive. Usually, an aqueous dye has a salt of a sulfonic acid group and / or a carboxyl group in its dye molecule, and is made water-soluble by the salt. Therefore, the aqueous dye is
It 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. Examples of such an adhesive component include natural rubber, modified natural rubber, and synthetic rubber. Therefore, since the water-based dye and the adhesive component of the conventional cold seal adhesive are both negatively charged and do not electrically attract each other, it is considered that the water-based dye is difficult to be fixed to the conventional cold seal adhesive.

By the way, as printing paper for ink jet printers, special paper is used for imparting water resistance to ink jet recorded prints. 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 polymer, polyallyl amine, poly Diallylamine, alkylamine / epichlorohydrin condensates, polyamine / epichlorohydrin-based polymers, polyalkylene polyureas, polyamide polyureas, dimethylallyl ammonium chloride, cationic vinyl copolymers and the like are disclosed (JP-A-7-315632 and See Japanese Patent Laid-Open No. 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 imparted to ink jet recorded prints in the same manner.
For example, Japanese Laid-Open Patent Publication No. 10-52985 discloses a cold seal adhesive suitable for ink jet recording by adding a cationic polymer, which is usually used for recording paper for ink jet printers, to a conventional cold seal adhesive. Is disclosed. However, although the water resistance and non-transferability of the ink jet recorded print are improved,
It is described that the viscosity of the cold seal adhesive has a large thixotropic property and the characteristics are not always stable. further,
In this method, since the cationic polymer has high water solubility,
There is also the problem of offset printing suitability that the offset plate is soiled during offset printing.

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 amount added is small, it is not possible to impart sufficient water resistance and non-transferability to ink-jet recorded printing. 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. Furthermore, in order to improve the water resistance and non-transferability of ink jet recorded prints, increasing the amount of the cationic polymer added to the conventional cold seal adhesive increases the cold seal adhesive immediately or during storage. It was also confirmed that the viscosity increase, the generation of agglomerates and / or gelation occurred, which made it impossible to use as a cold seal adhesive.

Therefore, simply by blending the conventional cold seal adhesive with the conventionally used cationic polymer, the water resistance of the ink-jet recorded print is improved and 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 ink jet recording, which has low transferability and good offset printing suitability.

In addition, in order to improve the color developability and the water resistance of ink jet recorded prints,
Many studies have been conducted on the inclusion of fillers in cold seal adhesives. However, if the amount of filler added is large,
When offset printing is performed on paper coated with a cold seal adhesive, the strength of the adhesive layer formed by the cold seal adhesive is temporarily reduced by so-called fountain solution used for printing. As a result, there is the problem that a portion of the cold seal adhesive layer containing the filler may peel off the surface of the coated paper and contaminate the printing plate. Further, for the same reason, there is a problem that a layer of the cold seal adhesive applied and formed on the base sheet may be powdered by abrasion and may contaminate the printing plate in the turn bar of the printing / foaming line. .

[0020]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem. The problem is to apply a cold seal adhesive to the surface of a base sheet to be printed and dry it. After printing and recording using an inkjet printer, or after printing information on the surface of the substrate sheet to be printed, apply a cold seal adhesive and dry, then use an inkjet printer. After recording, if water adheres to the print part, the water-based dye of the inkjet printer will bleed into water or dissolve in water, which is a problem of water resistance of the print, and the print will be pressed when the inkjet-recorded surface is pressed and then peeled off. Transferability problem of printing that transfers to other surface, wear that the layer of cold seal adhesive applied and formed on the base sheet falls off due to wear At least one of the above problems is alleviated, preferably substantially eliminated, and further, offset printing suitability is good, and these characteristics can be easily adjusted appropriately, and the cold performance is high. It is to provide a seal adhesive.

[0021]

According to the first aspect of the present invention, a new cold seal adhesive is provided, which comprises component (A): natural rubber latex, modified natural rubber latex, and synthetic rubber latex. A cold seal adhesive comprising at least one selected from the following, and component (B): at least one selected from amphoteric polymers, wherein a 1N NaCl aqueous solution represented by the following formula (1) is used as a solvent. And
The specific viscosity (η _sp ) of a 10 wt% solution of the component (B) (hereinafter, also referred to as “specific viscosity of the component (B)”) is 0.5 to
It is a cold seal adhesive that is 4.0.

Formula (1): η _sp = (η-η ⁰ ) / η ⁰ [In the formula (1), η ⁰ represents the viscosity of a 1N NaCl aqueous solution at 30 ° C., and η is 1N Na
The viscosity at 30 ° C. of a 10% by weight solution of component (B) in an aqueous Cl solution is shown. ]

In one embodiment of the cold seal adhesive of the first aspect, the component (B) has 1 to 1 parts derived from at least one selected from a chain transfer agent and an allyl compound based on the component (B). A cold seal adhesive of the first aspect containing 10% by weight is provided.

According to the second aspect of the present invention, there is also provided a new cold seal adhesive, which is a cold seal adhesive comprising the component (A) and the component (B) and is amphoteric. The polymer is obtained by copolymerizing a monomer mixture containing a cationic monomer and an anionic monomer as essential components, and the cationic monomer has an amino group and an ethylenic double bond. At least selected from a monomer, a monomer having a pyridyl group and an ethylenic double bond, a monomer having an ammonium base and an ethylenic double bond, and a monomer having a pyridinium base and an ethylenic double bond. The anionic monomer includes a monomer having a carboxyl group and an ethylenic double bond, a monomer having a carboxylate group and an ethylenic double bond, a sulfonic acid group and an anionic monomer. A monomer having a lenic double bond, a monomer having a sulfonate group and an ethylenic double bond, a monomer having a phosphate group and an ethylenic double bond, and a phosphate group and an ethylenic double bond In a cold seal adhesive comprising at least one selected from the monomers having 1 to 10% by weight of at least one selected from a chain transfer agent and an allyl compound.
It is a cold seal adhesive containing.

As one embodiment of the cold seal adhesive of the second aspect, the specific viscosity of the component (B) is 0.5 to.
A cold seal adhesive according to the second aspect above, which is 4.0.

Further, the present invention provides a cold seal adhesive in which the allyl compound is methallyl sulfonate as one embodiment of the above-mentioned first and second cold seal adhesives. The present invention also provides a cold seal adhesive in which the chain transfer agent is a thiol compound, as another aspect of the cold seal adhesive described above. Furthermore,
The present invention provides a cold seal adhesive in which the component (B) contains a quaternary ammonium salt group as another aspect of the above cold seal adhesive. Furthermore, the present invention provides, as one preferred embodiment of the cold seal adhesive described above,
The cation group / anion group (molar ratio) of the component (B) is 7
A cold seal adhesive that is 0/30 to 90/10 is provided.

The present invention also provides a cold seal adhesive which further comprises amorphous silica as another preferred embodiment of the above cold seal adhesive. Furthermore, the present invention provides a cold seal adhesive further comprising a cationic polymer as another preferred embodiment of the cold seal adhesive described above. All of the cold seal adhesives mentioned above are particularly suitable for inkjet recording. In the following description of the present specification, unless otherwise specified, the part where the solvent is not taken into consideration is based on parts by weight and% by weight.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION In the present specification, "component (A)"
Is a so-called "adhesive component",
A component which has a self-adhesive property as a main component of adhesive strength, and may be a combination of these, as long as at least one selected from natural rubber latex, modified natural rubber latex and synthetic rubber latex is included. Ingredient (A)
As the above, it is possible to use the one used as the adhesive component of the conventional cold seal adhesive. As such an adhesive component (A), specifically, JP-A-5-295 can be used.
335, JP-A-5-186640, JP-A-9-310055 and the like are included, which are appropriately selected according to the desired characteristics and used as the component (A) of the present invention. Can be used. 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 refers to an emulsion of naturally occurring rubber, which is usually called "natural rubber latex", to obtain the intended cold seal adhesive of the present invention. As long as it is possible, it is not particularly limited.

The "modified natural rubber latex" refers to a natural rubber latex obtained by addition-polymerizing (or radical-polymerizing) a natural rubber latex with a compound having an ethylenic carbon-carbon double bond, and modifying its characteristics. It is usually called "modified natural rubber latex" and is not particularly limited as long as the intended cold seal adhesive of the present invention can be obtained.

As the modified natural rubber latex, for example,
Examples of the natural rubber latex modified by addition-polymerizing the natural rubber latex with (meth) acrylic acid alkyl esters and a compound having various ethylenic carbon-carbon double bonds such as styrene. Specifically, an acrylic-modified natural rubber latex modified by copolymerizing alkyl (meth) acrylates 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 is a type and a compound of addition polymerization depending on desired properties. The amount of polymerization can be appropriately selected.
The modified natural rubber latex can be produced by a known method, but a commercially available product may be used. The modified natural rubber latex can be used alone or in combination.

The term "synthetic rubber latex" means an emulsion of synthetic rubber and is not particularly limited as long as the intended cold seal adhesive of the present invention can be obtained. Examples of synthetic rubber latex include styrene-butadiene rubber (SBR) latex and nitrile-
Butadiene rubber (NBR) latex, methylmethacrylate-butadiene rubber (MBR) latex, neoprene latex and the like can be exemplified (JP-A-5-186).
640). The synthetic rubber latex can be produced by a known method, but a commercially available product may be used.
The synthetic rubber latex can be used alone or in combination. Such various natural rubber latex, modified natural rubber latex, and synthetic rubber latex can be used alone or in combination as the component (A).

In the present specification, the "component (B)" may include at least one selected from amphoteric macromolecules, and various amphoteric macromolecules described below may be used alone or in combination as the component (B). Can be used. In the present specification, the "amphoteric polymer" is a monomer mixture containing "anionic monomer (D)" and "cationic monomer (E)" as essential components, and "other polymerization" Possible monomer (F) ”, which means an amphoteric polymer obtained by copolymerization (addition polymerization or radical polymerization) of a monomer mixture which may include an anionic group and a cationic group. Refers to a molecule.

Here, the "anionic monomer (D)" means
A compound having at least one anion group and at least one double bond between ethylenic carbon atoms, which provides an anionic group to a target amphoteric polymer through a polymerization reaction (addition polymerization or radical polymerization). Refers to the compound.

[0034] An "anionic group" as used herein, functional groups (e.g., having a negative charge, -COO ^- and -SO ₃ ^-
Etc.) (negative charges are electrically neutralized by a counter cation functional groups (e.g., -COO ^- Na ⁺ and -SO ₃ ^- K ⁺
Etc.) and a functional group capable of releasing a hydrogen ion in water to form a functional group having a negative charge (for example, —COOH).
And —SO ₃ H etc.). These "functional group having a negative charge" and "functional group capable of releasing a hydrogen ion in water to form a functional group having a negative charge" are those capable of changing the condition around each functional group, for example, pH. It goes without saying that they can be easily converted to each other. Regarding the "anionic group" in the present invention, these functional groups can be used alone or in combination depending on the characteristics of the amphoteric polymer.

Here, as the “functional group having a negative charge (including a functional group in which a negative charge is electrically neutralized by a counter cation)”, for example, a carboxylate group (—COO ⁻ and —COOM ¹ ), sulfonate (-SO ₃ ^- and -S
O ₃ M ^2), and phosphate groups _{^{(-PO 4 H -, -PO 4}} 2- , and -PO ^₄ M ³ M ₄₎ or the like can be exemplified [where, M ^1, M ^2,
M ³ and M ⁴ are alkali metal, alkaline earth metal or ammonium (it is to be noted that either one of M ³ and M ⁴ may be hydrogen)]. Furthermore, as the “functional group capable of releasing a hydrogen ion in water to form a functional group having a negative charge”, for example, a carboxyl group (—COOH), a sulfonic acid group (or a sulfo group) (—SO ₃ H), and can be exemplified a phosphate group (-PO ₄ H _2).

In the present specification, “between ethylenic carbon atoms
The “double bond” means a polymerization reaction (addition polymerization or radical polymerization).
Double bond between possible carbon atoms. Such a
Examples of functional groups containing double bonds between carbon atoms
For example, vinyl group (CH₂= CH-), (meth) allyl group
(CH₂= CH-CH₂-And CH₂= C (CH₃) -CH
₂-), (Meth) acryloyloxy group (CH₂= CH-
COO- and CH₂= C (CH₃) -COO-), and-
COO-CH = CH-COO- etc. can be illustrated.

Examples of such "anionic monomer (D)" include the following compounds: (D1) Half-esters of acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid and maleic acid. Compounds having a carboxyl group and an ethylenic carbon atom double bond, such as, and carboxylate groups and compounds having an ethylenic carbon atom double bond; (D2) Sulfonic acid groups such as styrenesulfonic acid and an ethylenic carbon atom A compound having an intercarbon double bond, and a compound having a sulfonate group and an ethylenic carbon atom double bond; (D3) a phosphoric acid group such as (meth) acrylic acid oxyethylamide phosphate and an ethylenic carbon atom diamine Compounds having a heavy bond, and compounds having a phosphate group and an ethylenic double bond between carbon atoms.

The counter cations of the carboxylate group, sulfonate group and phosphate group are preferably ammonium ions and alkali metal ions, and more preferably ammonium ions, potassium ions and sodium ions. In particular, acrylic acid and methacrylic acid are preferable as the anionic monomer (D). These anionic monomers (D) may be used alone or in combination depending on the characteristics of the target amphoteric polymer.

Further, the "cationic monomer (E)" is a compound having at least one cationic group and at least one double bond between ethylenic carbon atoms, which is polymerized to a desired amphoteric polymer. By a reaction (addition polymerization or radical polymerization) is meant a compound that will provide a cationic group.

In the present specification, the term "cationic group" means positive
A charged functional group (eg, -N ⁺(CH₃)₃And-
C_FiveH_FourN⁺-CH₃Etc.) (electrically medium by counter anion
Functional groups that are hydrated (eg, -N⁺(CH₃)₃Cl^-Over
And -C_FiveH_FourN⁺-CH₃Br^-Etc.), including underwater
To form a positively charged functional group by accepting hydrogen ions at
Functional group to be obtained (for example, -N (CH₃)₂And -C_FiveH_FourN
Etc.) are included. These "functional groups having a positive charge" and
"The functional group that accepts hydrogen ions in water and has a positive charge
The “functional group that can be formed” means the state around each functional group, for example,
For example, it can be easily converted to each other by changing pH etc.
It goes without saying that it is Noh. In the present invention,
The “on group” depends on the characteristics of the target amphoteric polymer.
Then, these functional groups are used alone or in combination.
be able to.

Here, as the "functional group having a positive charge",
For example, ammonium base ((-NR³R^FourR^Five)⁺as well as
(-NR³R^FourR^Five)⁺X^-) And pyridinium base ((-
C_FiveH_FourN-R⁶)⁺And (-C_FiveH_FourN-R⁶)⁺X^-) Example
Can be shown [however, R³, R^Four, R^Five, And R⁶Is hydrogen,
Chill group, ethyl group, benzyl group, phenyl group, or
A methylphenyl group, X^-Is chlorine ion and bromine
Halogen ion such as ion, acetate ion (CH₃CO
O^-), Sulfate ion (SO_Four ^2-), Nitrate ion (N
O₃ ^-), Perchlorate ion (ClO_Four ^-), Methylsulfate
(CH₃SO_Four ^-), Ethyl sulfate ion (C₂H_FiveS
O_Four ^-), And p-toluenesulfonate ion (CH₃
C₆H_FourSO₃ ^-) Etc.].

Further, as "a functional group capable of receiving a hydrogen ion in water to form a functional group having a positive charge", for example,
Amino group (-NR ⁷ R ⁸ ) [wherein R ⁷ and R ⁸ are hydrogen,
A methyl group, an ethyl group, a benzyl group, a phenyl group, or a methylphenyl group] and a pyridyl group (-C ₅ H ₄
N) can be illustrated. "Double bond between ethylenic carbon atoms"
Is the same as the content described in the description of "anionic monomer (D)".

Examples of such "cationic monomer (E)" include the following compounds: (E1) Compound having primary amino group and ethylenic carbon-carbon double bond, and primary A compound having an ammonium base and an ethylenic carbon atom double bond; (E2) a compound having a secondary amino group and an ethylenic carbon atom double bond, and a secondary ammonium base and an ethylenic carbon atom double bond A compound having (E3) a compound having a tertiary amino group and an ethylenic carbon-carbon double bond, and a compound having a tertiary ammonium base and an ethylenic carbon-carbon double bond; (E4) a quaternary ammonium base and ethylene A compound having an organic carbon-carbon double bond; (E5) a compound having a pyridyl group and an ethylenic carbon-carbon double bond, Compound having a double bond between pyridinium bases and ethylenic carbon atoms.

As the "cationic monomer (E)", the following compounds are more preferable: As (E1), for example,
(Meth) acrylic acid ester having a primary amino group, and (meth) acrylic acid ester in the form of a salt thereof having a primary ammonium group; (E2), for example, (meth) ) Acrylic acid ester having a secondary amino group, and (meth) acrylic acid ester in the form of a salt thereof having a secondary ammonium group; (E3), for example, (meth) acryl Acid 2- (N, N-dimethylamino) ethyl, (meth) acrylic acid 2- (N, N-)
Diethylamino) ethyl, (meth) acrylic acid 2-
(N, N-dibutylamino) ethyl, 3- (N, N-dimethylamino) propyl (meth) acrylate, (meth)
2- (N, N-methylethylamino) ethyl acrylate, 2- (N, N-ethylbutylamino) ethyl (meth) acrylate, and 2- (N, N- (meth) acrylic acid
(Meth) acrylic acid ester such as ethylbenzylamino) ethyl having a tertiary amino group, and (meth) acrylic acid ester in the form of a salt thereof having a tertiary ammonium group, and 3-
(Meth) acrylamides such as (N, N-dimethylamino) propyl (meth) acrylamide having a tertiary amino group, and salts thereof in the form of (meth)
A compound having acrylamide and a tertiary ammonium salt group; (E4), for example, (meth) acrylic acid 2- (N, N-dimethylamino) ethylmethyl chloride salt, (meth) acrylic acid 2- (N, N) -Dimethylamino) ethylbenzyl chloride salt, and (meth) acrylic acid ester such as 3- (N, N-dimethylamino) propyl epichlorohydrin hydrochloride (meth) acrylate, which has a quaternary ammonium salt group; and 3 −
(N, N-dimethylamino) propyl (meth) acrylamide epichlorohydrin hydrochloride and other (meth) acrylamide compounds having a quaternary ammonium salt group;
Examples of (E5) include (meth) acrylic acid 2- (4
-Pyridyl) ethyl, 3- (4-pyridyl) propyl (meth) acrylate, and 4- (4- (meth) acrylic acid
A compound having a pyridyl group, which is a (meth) acrylic acid ester such as pyridyl) butyl, further 2- (N-methylpyridinium) ethyl chloride (meth) acrylate,
2- (N-ethylpyridinium) ethyl bromide (meth) acrylic acid, 2- (N-butylpyridinium) ethyl chloride (meth) acrylic acid, 3- (meth) acrylic acid
(N-methylpyridinium) propyl chloride and 2- (N-benzylpyridinium) (meth) acrylate
(Meth) acrylic acid esters such as ethyl chloride having a pyridinium base, further compounds having a vinyl group and a pyridyl group such as vinylpyridine, N-methylvinylpyridinium chloride, N-ethylvinylpyridinium chloride, and A compound having a vinyl group such as N-phenylvinylpyridinium chloride and a pyridinium base.

Examples of the counter anions of the above-mentioned ammonium base and pyridinium base include halogen ions such as chloride ion and bromine ion, acetate ion, sulfate ion, nitrate ion, and perchlorate ion. These cationic monomers can be appropriately used alone or in combination depending on the characteristics of the target amphoteric polymer.

Further, among the above-mentioned cationic monomers, when the base sheet coated with the cold seal adhesive of the present invention to form an adhesive layer is used for an ink jet printer, it is used as an ink jet aqueous dye. In order to impart sufficient water resistance, “(E3) and (E
At least one selected from 4) is preferably contained in the above cationic monomer in an amount of 10 to 100% by weight, more preferably 50 to 100% by weight, and 8
It is particularly preferable that the content is 0 to 100% by weight.

When used in this ink jet printer, the following compounds are more preferable as at least one selected from the above (E3) and (E4):
A (meth) acrylic acid ester such as 2- (N, N-dimethylamino) ethyl (meth) acrylate or 2- (N, N-diethylamino) ethyl (meth) acrylate, which is 3
Compounds having a secondary amino group; (meth) acrylic acid 2-
(N, N-dimethylamino) ethylmethyl chloride salt,
(Meth) acrylic acid 2- (N, N-dimethylamino) ethylbenzyl chloride salt, and (meth) acrylic acid 3-
(N, N-dimethylamino) propyl epichlorohydrin hydrochloride and other (meth) acrylic acid esters having a quaternary ammonium salt group; and 3- (N, N)
-(Meth) acrylamides such as dimethylamino) propyl (meth) acrylamide epichlorohydrin hydrochloride, which have a quaternary ammonium salt group.

When used in an ink jet printer, at least one selected from the above (E3) and (E4) is, in particular, (meth) acrylic acid 2-
(N, N-dimethylamino) ethylmethyl chloride salt,
(Meth) acrylic acid 2- (N, N-dimethylamino) ethylbenzyl chloride salt, (meth) acrylic acid 3-
(N, N-Dimethylamino) propyl epichlorohydrin hydrochloride, 3- (N, N-dimethylamino) propyl (meth) acrylamido epichlorohydrin hydrochloride, and (meth) acrylic acid 2- (N, N-diethylamino)
Ethyl and the like are preferred. The "cationic monomer" preferably includes a monomer having a quaternary ammonium salt group.

The monomer mixture for obtaining the amphoteric polymer is
It is preferable that the anionic monomer (D) is contained in an amount of 2 to 30% by weight and the cationic monomer (E) is included in an amount of 50 to 98% by weight,
It is more preferable to contain the anionic monomer (D) in an amount of 2 to 15% by weight and the cationic monomer (E) in an amount of 70 to 98% by weight.

The molar ratio of the cation groups of the "cationic monomer (E)" to the anion groups of the "anionic monomer (D)" contained in the monomer mixture (cation group / anion group) is It is preferably 70/30 to 90/10.

Further, the monomer mixture may contain another polymerizable monomer (F). Here, the "other polymerizable monomer (F)" means the above-mentioned anionic monomer (D).
And an ethylenic carbon atom which is a compound other than the cationic monomer (E) and can be copolymerized (addition polymerization or radical polymerization) with the anionic monomer (D) and the cationic monomer (E). A compound having an inter-double bond. The “double bond between ethylenic carbon atoms” has the same meaning as described in the description of “anionic monomer (D)”.

Examples of such "other polymerizable monomer (F)" include the following compounds: (F1) methyl (meth) acrylate, ethyl (meth) acrylate, (meth) Propyl acrylate, butyl (meth) 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; (F2) Epoxy such as glycidyl (meth) acrylate (Meth) acrylic acid ester having a group; (F3) styrene such as styrene and vinyltoluene; and derivatives of styrene; (F4) alkene such as ethylene; and butadiene,
Dienes such as isoprene; (F5) Vinyl ester compounds such as vinyl acetate and vinyl propionate; (F6) Chlorinated vinyl compounds such as vinyl chloride and vinylene chloride; (F7) Having a cyano group such as acrylonitrile Compounds having an ethylenic carbon-carbon double bond; (F8) Compounds having a polyoxyalkylene group such as polyoxyethylene (meth) acrylate and polyoxypropylene (meth) acrylate and an ethylenic carbon-carbon double bond. These other polymerizable monomers (F) are
They can be used alone or in combination.

In the present specification, the "amphoteric polymer" can be obtained by copolymerizing a monomer mixture containing a cationic monomer and an anionic monomer as essential components. Is a monomer having an amino group and an ethylenic double bond, a monomer having a pyridyl group and an ethylenic double bond, a monomer having an ammonium base and an ethylenic double bond, and a pyridinium base and an ethylenic di bond. Containing at least one selected from monomers having a heavy bond, the anionic monomer has a monomer having a carboxyl group and an ethylenic double bond, a carboxylate group and an ethylenic double bond Monomer, monomer having sulfonic acid group and ethylenic double bond, monomer having sulfonate group and ethylenic double bond, monomer having phosphoric acid group and ethylenic double bond Preferably comprises at least one selected from a monomer having a body and a phosphate group and an ethylenic double bond.

Further, the above-mentioned monomer mixture may contain a chain transfer agent. The "chain transfer agent" is a compound capable of controlling the molecular weight of the target amphoteric polymer by addition in a small amount, and is preferably a compound which can be used in an aqueous solvent and an organic solvent. Examples of such a “chain transfer agent” include 2-mercaptoethanol and n.
Examples thereof include thiol compounds such as octyl mercaptan, disulfides such as tetramethylthiuram disulfide, and halogen compounds such as chloroform. Particularly, thiol compounds such as 2-mercaptoethanol and n-octylmercaptan are preferable.

The amphoteric polymer can be produced by polymerizing the monomer mixture (addition polymerization or radical polymerization) by using an ordinary polymerization method, and optionally using a catalyst or the like. The polymerization reaction may be carried out in an aqueous solvent,
After polymerizing in an organic solvent, the solvent may be converted to an aqueous solvent. The conditions of the polymerization reaction such as reaction temperature, reaction time, type of solvent, type and concentration of monomer mixture, stirring speed, and type and concentration of catalyst are appropriately selected depending on the characteristics of the target amphoteric polymer and the like. I will get it.

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-diamidinopropane) dihydrochloride, 2,2-azobis (2,4-dimethylvaleronitrile) and the like can be exemplified, and particularly 2,2
-Azobisisobutyronitrile (AIBN) and 2,2
-Azobis (2-diamidinopropane) dihydrochloride is preferred.

In the present specification, the "aqueous solvent" is mainly so-called water such as distilled water, ion-exchanged water, and pure water, but a water-soluble organic solvent such as acetone and lower alcohol is used. It can be included as appropriate. Further, in the present specification, 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, for example, methanol, ethanol,
Examples include propanol, butanol, ethyl acetate, and the like, and combinations thereof.

Regarding the cold seal adhesive according to the first aspect of the present invention, the specific viscosity of the component (B) represented by the following formula (1) is 0.5 to 4.0.

Formula (1): η _sp = (η-η ⁰ ) / η ⁰ [In the formula (1), η ⁰ represents the viscosity of a 1N NaCl aqueous solution at 30 ° C., and η is 1N Na
The viscosity at 30 ° C. of a 10% by weight solution of component (B) in an aqueous Cl solution is shown. ] In the case of the cold seal adhesive of the first summary, the component (B)
The specific viscosity is preferably 0.5 to 2.0, and the specific viscosity of 0.
Particularly preferably, it is 5 to 1.0.

The equation (1) can be transformed into the following equation (2).

Equation (2): η _sp = (η-η ⁰ ) / η ⁰ = η / η ⁰ −1 = t / t ⁰ −1 [where, in the formula (2), t ⁰ is 1N Flow time of the aqueous NaCl solution at 30 ° C., t is 10% by weight of the amphoteric polymer in a 1N aqueous NaCl solution as a solvent.
Flow time of the solution at 30 ° C. (Here, the flow down time represents the time required for the solution to flow down through the capillary of the Ubbelohde viscometer.)]

Therefore, the specific viscosity of the component (B) is specifically 1N N at 30 ° C. using an Ubbelohde viscometer.
The flowing-down time (t ⁰ ) of the aCl aqueous solution and the flowing-down time (t) of the 10 wt% solution of the component (B) using the 1N NaCl aqueous solution as a solvent are measured, and are calculated using the formula (2).

In the case of the cold seal adhesive according to the first aspect described above, the component (B) includes a portion derived from at least one selected from a chain transfer agent and an allyl compound, based on the component (B). It is preferable to contain 10% by weight. In the case of the cold seal adhesive according to the first aspect, the component (B) contains 0.1 to 2.0 parts derived from the chain transfer agent.
It is more preferable that the content is 0.5% by weight, particularly preferably 0.5 to 1.0% by weight. More preferably, the portion derived from the allyl compound is contained in an amount of 1.0 to 10% by weight, and 5.0 to 1
It is particularly preferable to contain 0% by weight. As mentioned above,
The weight% of the component (B) is based on the part of the component (B) not considering the solvent.

In the case of the cold seal adhesive of the first aspect, the component (B) is an amphoteric compound obtained by polymerizing a monomer mixture containing at least one selected from a chain transfer agent and an allyl compound. It can be obtained by using a polymer. The monomer mixture contains 1 to 10% by weight of at least one selected from a chain transfer agent and an allyl compound.
It is preferable to include. The monomer mixture contained a chain transfer agent of 0.
It is more preferable to contain 1 to 2.0% by weight, and 0.5 to 1.
It is particularly preferable to contain 0% by weight. More preferably, the monomer mixture contains 1.0 to 10% by weight of the allyl compound,
It is particularly preferable to contain 5.0 to 10% by weight.

In the present specification, the "chain transfer agent" is the above-mentioned chain transfer agent, preferably a thiol compound. The chain transfer agent is used as a part of the monomer mixture when producing the amphoteric polymer as described above, and becomes a part constituting the amphoteric polymer. The "allyl compound" in the present specification, "an allyl group _{(CH 2 = CH-CH 2} -) and / or methallyl group _{(CH 2 = C (CH 3} ) -CH
₂₋ ) ”, and similar to a chain transfer agent,
It is used in the production of an amphoteric polymer for the purpose of controlling the molecular weight of the amphoteric polymer, and is copolymerized to become a part constituting the amphoteric polymer.

Therefore, since the "allyl compound" is a compound having an ethylenic carbon-carbon double bond, more specifically, the above-mentioned "cationic monomer" and "anionic monomer". And "other polymerizable monomers" correspond to compounds in which the functional group having an ethylenic carbon-carbon double bond is an allyl group or a methallyl group.

Examples of the "allyl compound" which also corresponds to the "cationic monomer" include allyl compounds having an amino group such as N, N-dimethylallylamine, N, N-diethylallylamine and allylamine. It can be illustrated. Examples of the "allyl compound" that also corresponds to the "anionic monomer" include, for example, allyl compounds having a sulfonic acid group such as allylsulfonic acid and methallylsulfonic acid, sodium allylsulfonate, and potassium allylsulfonate. And allyl sulfonates, and methallyl sulfonates such as sodium methallyl sulfonate and potassium methallyl sulfonate (both allyl sulfonate and methallyl sulfonate are combined as “allyl compound having sulfonate group”). "Also referred to as") and the like. Examples of compounds that are “allyl compounds” and also correspond to “other polymerizable monomers” include, for example, allyl alcohol, allyl glycidyl ether, 4-penten-2-ol, allyl acetate, allylbenzene, n-butyric acid. Examples include allyl and allyl n-caprate. The allyl compounds can be used alone or in combination.

On the other hand, in the cold seal adhesive according to the second aspect of the present invention, the monomer mixture contains 1 to 10% by weight of a portion derived from at least one selected from a chain transfer agent and an allyl compound. In the case of the cold seal adhesive of the second aspect, the monomer mixture comprises a chain transfer agent of 0.
It is more preferable to contain 1 to 2.0% by weight, and 0.5 to 1.
It is particularly preferable to contain 0% by weight. Furthermore, the monomer mixture is
More preferably, the allyl compound is contained in an amount of 1.0 to 10% by weight, particularly preferably 5.0 to 10% by weight. The “chain transfer agent” and the “allyl compound” are as described above.

In the cold seal adhesive of the second aspect of the present invention, the component (B) has a specific viscosity of 0.5 to 4.0 represented by the formula (1). Is preferred.

Formula (1): η _sp = (η-η ⁰ ) / η ⁰ [In the formula (1), η ⁰ represents the viscosity of a 1N NaCl aqueous solution at 30 ° C., and η is 1N Na
The viscosity at 30 ° C. of a 10% by weight solution of component (B) in an aqueous Cl solution is shown. ] In the case of the cold seal adhesive of the second aspect, the specific viscosity of the component (B) is 0.5 to
2.0 is more preferable, and 0.5 to 1.0 is particularly preferable. In addition, a modification of the formula (1) and a component (B)
The specific measuring method of the specific viscosity of is the same as that described for the cold seal adhesive of the first summary.

In the present invention, the electrical characteristics of the component (B), that is, the strength of the positive and negative charges, the total charge, etc., can be easily adjusted by appropriately selecting the composition of the monomer mixture into a preferable combination. be able to. Therefore, since it is easy to adjust the water resistance and non-transferability of the print according to the type of the aqueous dye, it is possible to easily provide the cold seal adhesive that appropriately corresponds to the type of the aqueous dye.

In the present invention, by controlling the molecular weight of the component (B) within a specific range, it becomes easier to control the water resistance and non-transferability of the printing of the aqueous dye. Therefore, in the cold seal adhesive according to the first aspect of the present invention, the specific viscosity of the component (B) is controlled to a specific value (0.5 to 4.0), and the cold seal adhesive according to the present invention is also used. In the cold seal adhesive of the second aspect, an amphoteric polymer obtained by polymerizing a monomer mixture containing a specific amount of at least one selected from an allyl compound and a chain transfer agent is used as the component (B).

For the above-mentioned object of the present invention, it is of course necessary that the molecular weight of the component (B) can be directly measured, but the component (B) is a gel widely used as an ordinary molecular weight measuring method. It is difficult to detect the molecular weight normally by using the permeation chromatography method. It is considered that this is because, since the component (B) is charged, it is difficult to desorb the component (B) once it is adsorbed on the gel in the column. Therefore, for the purpose of controlling the molecular weight of the component (B), the specific viscosity having a correlation with the molecular weight is controlled. Further, for the purpose of controlling the molecular weight of the component (B), a specific amount of at least one selected from an allyl compound and a chain transfer agent which are compounds capable of controlling the molecular weight is used in the production of the component (B). That is what I did. still,
When the specific viscosity is high, the molecular weight is also high, and when the specific viscosity is low, the molecular weight is low.

Regarding the cold seal adhesive according to the present invention, when the specific viscosity of a 10% by weight solution of the component (B) in a 1N NaCl aqueous solution as a solvent is 0.5 to 4.0. It is preferable since the water resistance of ink jet recording on the layer of the cold seal adhesive and the offset printability of the layer of the cold seal adhesive are improved. The improvement in water resistance of inkjet printing is due to the fact that the component (B) has an appropriate water solubility when the specific viscosity is 4.0 or less, which facilitates the ionic interaction with the dye in the inkjet ink. Conceivable. Further, it is considered that the offset printing suitability is improved because the component (B) is less likely to be eluted in the fountain solution during the offset printing when the specific viscosity is 0.5 or more.
For these reasons, the cold seal adhesive according to the present invention is not limited at all.

The cold seal adhesive according to the present invention includes, as the component (B), for example, a (meth) acrylic acid ester compound having a quaternary ammonium salt group, a carboxyl group and an ethylenic carbon-carbon double bond. An amphoteric polymer obtained by addition-polymerizing a combination of a compound having a sulfonic acid group and an allyl compound having a sulfonic acid group, a compound having a quaternary ammonium base which is a (meth) acrylic acid ester, a carboxyl group and an ethylenic carbon atom An amphoteric polymer obtained by addition-polymerizing a combination of a compound having a heavy bond and a thiol compound, and a (meth) acrylic acid ester compound having a tertiary amino group, a carboxyl group and an ethylenic carbon-carbon double bond A high amphoteric compound obtained by addition polymerization of a combination of a compound having a bond and a thiol compound. It can be exemplified the child.

The cold seal adhesive according to the present invention includes, as the component (B), more specifically, for example, 2- (N, N-dimethylamino) ethyl methyl chloride methacrylate, acrylic acid and methallyl sulfonic acid. Of amphoteric polymers obtained by addition polymerization of a combination of
Amphoteric polymer obtained by addition polymerization of a combination of (N, N-dimethylamino) ethylbenzyl chloride salt, methacrylic acid and 2-mercaptoethanol, and 2- (N, N-dimethylamino) ethyl methacrylate, acrylic acid The amphoteric polymer obtained by addition-polymerizing the combination of and n-dodecyl mercaptan can be illustrated.

The "allyl compound" according to the present invention is preferably a methallyl sulfonate. Furthermore, the “chain transfer agent” according to the present invention is preferably a thiol compound. Further, the component (B) preferably contains a quaternary ammonium salt group. Furthermore, the cationic group of component (B) /
The anion group (molar ratio) is preferably 70/30 to 90/10.

In the cold seal adhesive of the present invention, 10 parts of the component (B) are added per 100 parts by weight of the component (A).
To 120 parts by weight, preferably 20 to 100 parts by weight, more preferably 30 to 90 parts by weight. As described above, the parts by weight of the component (A) and the component (B) are based on the part not considering the solvent of the component (A) and the component (B).

The cold seal adhesive according to the present invention preferably contains at least one kind selected from the below-mentioned fine particle filler as a "fine particle filler". The "fine particle filler" according to the present invention is a fine particle filler that is usually used for cold seal adhesives, and is not particularly limited as long as it does not adversely affect the cold seal adhesive of the present invention. is not. As such a fine particle filler, for example, amorphous silica, mica, calcium carbonate, kaolin, talc, diatomaceous earth, urea resin,
Examples thereof include styrene beads, calcined clay, grain starch, and modified starch.

Further, the fine particle filler is usually a particle, preferably spherical, and its size (diameter in the case of spherical shape) is
There is no particular limitation as long as the desired performance of the present invention is exhibited. These various fine particle fillers can be used alone or in combination and appropriately selected and used according to the required characteristics. By using a fine particle filler, properties such as adhesion, blocking resistance, printability, abrasion resistance, and adhesion to paper required for a cold seal adhesive can be easily and suitably adjusted. .

When a base sheet coated with the cold seal adhesive of the present invention to form an adhesive layer is used for recording in an ink jet printer, amorphous silica is used as a fine particle filler. Is preferred. In this case, the cold seal adhesive of the present invention comprises the component (A) 10
It is preferable to include 50 to 150 parts by weight of amorphous silica per 0 part by weight. Amorphous silica is excellent in the property of incorporating ink into the adhesive layer formed by the cold seal adhesive, and as a result, improves the color development of the ink and the amphoteric properties that may exist in the ink and the adhesive. It is considered to be effective in the expression of ionic interactions with macromolecules.

Further, the cold seal adhesive of the present invention comprises
10 to 1 parts of the component (B) per 100 parts by weight of the component (A)
20 parts by weight, preferably 50 to 150 parts by weight of amorphous silica, more preferably 20 to 100 parts by weight of component (B), and more preferably 50 to 150 parts by weight of amorphous silica. As described above, the parts by weight of the components (A) and (B) are based on the parts not considering the solvent of the components (A) and (B).

Further, the cold seal adhesive of the present invention comprises
It may include an auxiliary agent. Here, the “auxiliary agent” is an auxiliary agent that is usually used in a cold seal adhesive and is not particularly limited as long as it does not adversely affect the cold seal adhesive of the present invention. Normal,
The "auxiliary agent" refers to an agent that imparts blocking resistance, printability, abrasion resistance, adhesion to paper, and the like. Examples of the auxiliary agent include water-soluble resins such as polyvinyl alcohol (PVOH), starch, casein, polystyrene maleic acid and carboxymethyl cellulose, synthetic rubbers, acrylic emulsions, and polyolefin emulsions. The auxiliaries can be used alone or in combination.

The cold seal adhesive of the present invention is in the form of an aqueous emulsion and comprises component (A) and component (B).
Etc. have a form in which they are dispersed in an aqueous solvent. 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.

Further, the cold seal adhesive of the present invention comprises
It may comprise at least one selected from cationic polymers. In the cold seal adhesive of the present invention, further according to need and desired properties,
Additionally, a small amount of cationic polymer can be incorporated into the cold seal adhesive. Accordingly, when the base sheet having the adhesive layer formed by applying the cold seal adhesive of the present invention is used in an inkjet printer, the water resistance and non-transfer strength of the water-based dye can be easily adjusted. Can be adjusted to ensure the water resistance and non-transferability of printing.

The term "cationic polymer" as used herein means a polymer having a positive charge, and a cation as long as it does not adversely affect the adhesive properties of the cold seal adhesive when added in a small amount. The strength of the sex is not particularly limited. Examples of the cationic polymer include polydimethylamine ammonia epichlorohydrin, polydimethylamine ethylenediamine epichlorohydrin, etc.
No. 52985), diallyldimethylammonium chloride, polyamide / epoxy resin, polyamide / urea resin, aldehyde resin, melanin resin and the like (see JP-A-9-71758). 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 can be blended in the cold seal adhesive of the present invention. Here, as the “additive”, an additive which is usually used in a cold seal adhesive can be used if necessary. As additives, for example, lubricants, printability improvers, antioxidants, ultraviolet absorbers, conductive agents, fluorescent paints, coloring dyes, stabilizers, defoamers, fungicides, antibacterial agents, thickeners, and A moisturizer etc. can be illustrated. 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 to provide a cold seal adhesive having excellent printability, stability, and mold resistance. You can

The cold-seal adhesive of the present invention is suitable as a cold-seal adhesive in which a base sheet is coated with an adhesive to form an adhesive layer and adhesive is applied in order to obtain an information carrier. is there. Accordingly, the present invention provides a substrate sheet having an adhesive layer formed by applying the cold seal adhesive described above.

The present invention further provides an adhesive site in which a layer of adhesive is formed by applying the cold seal adhesive described above to a substrate sheet to obtain an information carrier. Here, the “adhesion site” refers to a site where a cold seal adhesive is applied to form an adhesive layer, but which is not adhered by applying pressure. Therefore, the present invention further provides an information carrier having the above-mentioned adhesion site. As such an information carrier, a confidential postcard is particularly preferable.

After the cold seal adhesive of the present invention is applied to a base sheet (for example, high-quality paper) to form an adhesive layer,
When the base sheet is further processed to form, for example, a confidential postcard as an information carrier, various forms of the confidential postcard can be appropriately selected depending on the information contained in the confidential postcard and the intended use. The form is not limited. As a form of such a confidential postcard, for example,
The adhesive layer is formed only on one side of the base sheet, and the two-sided spread postcard is formed by folding the base sheet in two and superposing it, and the adhesive layer is formed on only one side of the base sheet. , A so-called Z-fold is used to fold the base sheet into three, and a set of six-sided postcards in which a pair of facing two surfaces are pressure bonded, and an adhesive layer is formed on both sides of the base sheet,
An example is a hexagonal postcard in which the base sheet is folded in three by folding and two sets of two opposite faces are pressure-bonded.

As a method for applying the cold seal adhesive of the present invention, a method which is generally used as a method for applying a cold seal adhesive can be used.
The coating method is not particularly limited as long as the cold seal adhesive of the present invention can be coated. Examples of such coating methods include roll coaters, bar coaters, blade coaters, air knife coaters, rod blade coaters, and gravure roll coaters.

Further, in the present specification, "compression bonding" is a method conventionally used for bonding a cold seal adhesive, and a cold seal adhesive is applied to form an adhesive layer 2. It means to bond two surfaces together by stacking them so that they are in contact with each other and applying pressure and heat if necessary. Therefore, "compression bonding" also refers to applying pressure to the bonding site of the base sheet to bond the base sheet together.

[0090]

EXAMPLES The present invention will be described specifically and in detail below with reference to Examples and Comparative Examples, but these Examples are merely one aspect of the present invention, and the present invention is in no way limited by these Examples. is not. In the description of the examples, unless otherwise stated, the parts that do not take the solvent into consideration are based on parts by weight and% by weight.

(1) Production of amphoteric polymer and 1N NaC
Measurement of specific viscosity of a 10 wt% solution of an amphoteric polymer in an aqueous solution as a solvent (i) Production of amphoteric polymer B1 7 parts by weight of acrylic acid (A
A), 85 parts by weight of dimethylaminoethyl methacrylic acid benzyl chloride salt as a cationic monomer [(CH
_{2 = C (CH 3) COOCH} 2 CH 2 N (CH 3) 2 CH 2
C ₆ H ₅ ) ⁺ Cl ⁻ ] (DML), 10 parts by weight of polyethylene glycol monomethacrylate (PE350),
10 parts by weight of sodium methallylsulfonate [CH ₂ ═C (C
_{H 3) CH 2 SO 3 Na} ] was added to distilled water 900 parts by weight, stirring the catalyst 1 part by weight of the while 2,2-azobis (2-di-amidinopropane) dihydrochloride (V5
0) was added, the mixture was heated to 80 ° C. and reacted for 3 hours to obtain an amphoteric polymer B1 in the form of an aqueous solution.

(Ii) Measurement of specific viscosity of a 10% by weight solution of amphoteric polymer B1 in a 1N aqueous solution of NaCl as a solvent The above amphoteric polymer B1 was dried at 105 ° C. for 3 hours to substantially remove the solvent. After that, a 10 wt% solution of the amphoteric polymer B1 was prepared using a 1N NaCl aqueous solution as a solvent. 1
The specific viscosity of a 10 wt% solution of an amphoteric polymer in a N aqueous solution of NaCl as a solvent (hereinafter, also referred to as “specific viscosity of amphoteric polymer”) is represented by the formula (1) as described above.

Formula (1): η _sp = (η-η ⁰ ) / η ⁰ [In the formula (1), η ⁰ represents the viscosity of a 1N NaCl aqueous solution at 30 ° C., and η is 1N Na
The viscosity at 30 ° C. of a 10 wt% solution of an amphoteric polymer in a Cl aqueous solution as a solvent is shown. ]

The equation (1) can be further transformed into the equation (2).

Equation (2): η _sp = (η-η ⁰ ) / η ⁰ = η / η ⁰ −1 = t / t ⁰ −1 [where, in the formula (2), t ⁰ is 1N It represents the flow-down time of the NaCl aqueous solution, and t 2 represents the flow-down time of a 10 wt% solution of an amphoteric polymer in a 1N NaCl aqueous solution as a solvent. (Here, the "flow time" means the time required for the solution to flow down at 30 ° C in the capillary of the Ubbelohde viscometer.) Therefore, using an Ubbelohde viscometer, at 30 ° C, 1N
Of NaCl aqueous solution (t ⁰ ) and 1N NaCl
The flow time (t) of a 10 wt% solution of the amphoteric polymer B1 in an aqueous solution of 1 was measured, and a value of 0.7 was obtained as the specific viscosity of the amphoteric polymer B1 using the formula (2).

(Iii) Production of amphoteric polymers B2 to B7 and specific viscosity of amphoteric polymers B2 to B7 Amphoteric polymers B2 to B7
7 was produced by using the same method as the above-mentioned method for producing the amphoteric polymer B1 and using the amounts of the compounds shown in Table 1 shown in Table 1, and the amphoteric polymers B2 to B7 were all prepared in an aqueous solution. It was obtained in the form of In the production of amphoteric polymers B2 to B7, when 2-mercaptoethanol is used as a chain transfer agent, 2-mercaptoethanol reacts with 2,2-azobis (2-diamidinopropane) dihydrochloride before the reaction. Added to the container. Obtained amphoteric polymer B2
The specific viscosities of B7 to B7 were measured by the same method as the method described in the measurement of the specific viscosity of the amphoteric polymer B1 described above.
The results are shown in Table 1. The specific viscosity of commercially available cationic polymers was measured by the same method, and the results are shown in Table 1.

[0095]

[Table 1] a) The unit of the amount of the compound used is part by weight. b) dimethylaminoethyl methacrylate benzyl chloride salt _{[CH 2 = C (CH 3} ) -COO-CH 2 CH
^{_{2 N + (CH 3) 2}} -CH 2 C 6 H 5 · Cl -] c) dimethylaminoethyl methacrylate methyl chloride salt _{[CH 2 = C (CH 3} ) -COO-CH 2 CH 2
N ⁺ (CH ₃ ) ₃ · Cl ⁻ ] d) Acrylic acid [CH ₂ ═CH—COOH] e) Polyoxyethylene methacrylate (polyoxyethylene addition mole number n≈8) [CH ₂ ═CH (CH ₃ ) —
_{COO- (CH 2 CH 2 O)} n -H] f) 2,2- azobis (2-di-amidinopropane) dihydrochloride g) cationic polymer is a commercially available product.

(2) Manufacture of cold seal adhesive (i) Manufacture of cold seal adhesive of Example 1 Methyl methacrylate modified natural rubber latex obtained by copolymerizing natural rubber latex with methyl methacrylate by a conventional method. (Hereinafter "MMA modified natural rubber latex")
Also referred to as 100 parts by weight, 10 parts by weight of styrene-butadiene rubber (SBR) latex, 60 parts by weight of the above amphoteric polymer B1, 100 parts by weight of amorphous silica,
20 parts by weight of other fine particle fillers (such as starch) (total fine particle filler is 120 parts by weight), and 10 parts by weight of POVAL (PVOH: GoseiFimer Z210 (trade name) manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) Thus, the cold seal adhesive of Example 1 was obtained. The composition of the cold seal adhesive of Example 1 is shown in Table 2.

(Ii) Production of cold seal adhesives of Examples 2 to 9 and Comparative Examples 1 to 3 MMA-modified natural rubber latex, styrene-butadiene rubber (SBR) latex, amphoteric polymer described in Tables 2 and 3. Amorphous silica, other fine particle fillers (starch and the like), and components such as Poval were mixed in the parts by weight shown in Tables 2 and 3, and cold seal adhesion of Examples 2 to 9 and Comparative Examples 1 to 3 was performed. I got an agent.

(2) Evaluation of Cold Seal Adhesive (i) Stability of Cold Seal Adhesive Blending The stability of the cold seal adhesive blend was determined by the grit value of the adhesive (aggregation when the cold seal adhesive was blended). (The presence or absence of a product), the change with time of the viscosity of the cold seal adhesive, and the visual observation of the cold seal adhesive. The viscosity was measured using a B-type viscometer (30 ° C.).
Generation of grit was not observed, and viscosity was not substantially increased. ◎, Viscosity was increased even if generation of grit was not observed, but there was practically no problem ○, generation of grit was recognized. Although not observed, the one with a large increase in viscosity was marked with Δ, and the one in which the generation of grit was recognized or the gel with increased viscosity was marked with x. The results are shown in Tables 2 and 3.

(Ii) Preparation of water resistance and non-transferability test sheet for ink jet recorded printing Cold seal adhesive was coated on one side of a base sheet made of high quality paper (130 g / m ² ) after drying. Is 10 g /
A base sheet (hereinafter also referred to as an "adhesive-coated sheet") having an adhesive layer formed thereon was obtained by coating and drying so as to give m ² . After printing on the adhesive layer of this adhesive coating sheet using a black ink, red ink, blue ink and green ink manufactured by Cytex, using an inkjet printer, An adhesive coated sheet (hereinafter referred to as "test sheet") was obtained by drying in a dryer for 1 minute.

Evaluation of Water Resistance (Bleeding) of Inkjet-Recorded Printing The water resistance (bleeding) of an inkjet-recorded printing was evaluated by dropping water droplets on the printed portion of the test sheet and visually checking the printing state after air drying. It was done by observing. ◎ A test sheet with almost no bleeding on the print, ◯ a little bleeding but practically no problem, ○ a clear bleeding △, and bleeding that is difficult to read characters × And The results are shown in Tables 2 and 3. still,
In all of the examples and comparative examples, there was no difference in the results due to the difference in color type.

Evaluation of Water Resistance (Elution) of Inkjet-Recorded Print To evaluate the water resistance (elution) of ink-jet recorded print, visually observe the dissolution of the ink after the test sheet was immersed in water for 3 minutes. Went by. Ink is almost free of ink elution, Ink is slightly dissolved but is not a problem in practical use, Ink is clearly admitted Δ, ink is badly eluted and it is difficult to read characters. The case was marked as x. The results are shown in Tables 2 and 3.
In all of the examples and comparative examples, there was no difference in the results due to the difference in color type.

Evaluation of Non-Transferability of Inkjet-Recorded Print In order to evaluate the non-transferability of ink-jet-recorded print, the test sheet was folded back in half and pressed at a temperature of 20 ° C. and a humidity of 60% to be pressure-bonded. When re-peeling after a lapse of minutes, it was performed by visually observing the presence or absence of print transfer. As the pressing pressure, the pressure immediately before the test sheet was at least partially broken (material destruction) at the time of re-peeling was used. When the printing on the pressure test sheet was not transferred at all, it was marked with ⊚, when it was slightly transferred but there was no practical problem, it was marked with ◯, when there was some transfer, it was marked with Δ, and when transfer was bad, it was marked with x. The results are shown in Tables 2 and 3.

(Iii) Evaluation of Abrasion Resistance of Adhesive Layer The abrasion resistance (dry) was evaluated by using a Gakushin type abrasion resistance fastness tester, using a weight of 1000 g, and an adhesive coated sheet. After the surface was abraded 200 times, the state of the surface of the adhesive coating sheet was visually observed. The case where the surface of the adhesive-coated sheet is not scraped at all ⊚, the case where slight surface scraping is recognized is marked ○, the scrap is generated, and the scrap is less than 10%, the △ is marked. The case where a large amount was generated and the surface abrasion was 10% or more was marked with x. The results are shown in Tables 2 and 3.

[0104]

[Table 2] a) The unit of each component is parts by weight.

[0105]

[Table 3] a) The unit of each component is parts by weight.

[0106]

The cold seal adhesive according to the first aspect of the present invention comprises the component (B) (at least one selected from the amphoteric polymers), and the component (B) is a 1N NaCl aqueous solution. Since the specific viscosity of a 10 wt% solution containing 0.5 to 4.0 as a solvent is 0.5 to 4.0, at least one of the problem of water resistance of printing, the problem of transferability of printing and the problem of abrasion resistance is alleviated, It is possible to provide a cold seal adhesive which is preferably substantially eliminated, and has good offset printing suitability, and whose properties can be easily adjusted appropriately, and which has high overall performance.

Further, in the cold seal adhesive according to the first aspect, since the component (B) contains a portion derived from the chain transfer agent and the allyl compound in an amount of 1 to 10% by weight, the problem of water resistance of printing is reduced. In addition, at least one of the problem of transferability of printing and the problem of abrasion resistance can be alleviated and substantially eliminated.

In the cold seal adhesive according to the second aspect of the present invention, since the component (B) contains 1 to 10% by weight of the portion derived from the chain transfer agent and the allyl compound, there is a problem of water resistance of printing. At least one of the problem of transferability of printing and the problem of abrasion resistance is mitigated, preferably substantially eliminated, and further, offset printing suitability is good, and these characteristics can be easily adjusted appropriately. It is possible to provide a cold seal adhesive having high overall performance.

Further, in the cold seal adhesive of the second aspect, the specific viscosity of the component (B), 1N, is 0.5 to.
Since it is 4.0, at least one of the problem of water resistance of printing, the problem of transferability of printing, and the problem of abrasion resistance can be further alleviated and substantially solved.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4J040 CA011 CA021 CA071 CA141                       CA171 DB051 DL031 DN072                       GA07 GA13 GA14 GA17 GA25                       GA27 HC01 HD03 HD14 JA02                       JB09 KA18 LA01 LA06 MA09                       MA10

Claims (11)

[Claims] 1. Component (A): at least one selected from natural rubber latex, modified natural rubber latex, and synthetic rubber latex, and component (B): at least one selected from amphoteric polymers. A cold seal adhesive, which uses a 1N NaCl aqueous solution represented by the following formula (1) as a solvent,
The specific viscosity (η _sp ) of a 10 wt% solution of component (B) is
An adhesive characterized by being 0.5 to 4.0. ## EQU1 ## Formula (1): η _sp = (η-η ⁰ ) / η ⁰ [In the formula (1), η ⁰ represents the viscosity of a 1N NaCl aqueous solution at 30 ° C., and η is 1N The viscosity at 30 ° C. of a 10% by weight solution of component (B) in an aqueous solution of NaCl as a solvent is shown. ] 2. The component (B) has a moiety derived from at least one selected from a chain transfer agent and an allyl compound.
The cold seal adhesive according to claim 1, wherein the cold seal adhesive is contained in an amount of 10 to 10% by weight. 3. Component (A): at least one selected from natural rubber latex, modified natural rubber latex, and synthetic rubber latex, and component (B): at least one selected from amphoteric polymers. A cold seal adhesive, in which the amphoteric polymer is obtained by copolymerizing a monomer mixture containing a cationic monomer and an anionic monomer as essential components, and the cationic monomer is an amino monomer. A group and an ethylenic double bond, a pyridyl group and an ethylenic double bond, an ammonium base and an ethylenic double bond, and a pyridinium base and an ethylenic double bond. The anionic monomer includes a monomer having a carboxyl group and an ethylenic double bond, and a calcine. Monomers having acid group and ethylenic double bond, monomers having sulfonic acid group and ethylenic double bond, monomers having sulfonic acid group and ethylenic double bond, phosphate group and ethylene A cold-seal adhesive comprising at least one selected from a monomer having an organic double bond and a monomer having a phosphate group and an ethylenic double bond, wherein the monomer mixture is a chain transfer agent and A cold seal adhesive containing at least 1 to 10% by weight of an allyl compound. 4. The specific viscosity (η _sp ) of a 10 wt% solution of the component (B) in the 1N NaCl aqueous solution represented by the following formula (1) is 0.5 to 4.0. The cold seal adhesive according to claim 3, wherein Formula (1): η _sp = (η-η ⁰ ) / η ⁰ [wherein, in formula (1), η ⁰ represents the viscosity of a 1N NaCl aqueous solution at 30 ° C., and η is 1N The viscosity at 30 ° C. of a 10% by weight solution of component (B) in an aqueous solution of NaCl as a solvent is shown. ] 5. The cold seal adhesive according to claim 2, wherein the allyl compound is methallyl sulfonate. 6. The cold seal adhesive according to claim 2, wherein the chain transfer agent is a thiol compound. 7. The cold seal adhesive according to any one of claims 1 to 6, wherein the component (B) contains a quaternary ammonium salt group. 8. The cold seal adhesive according to claim 1, wherein the cationic group / anionic group (molar ratio) of the component (B) is 70/30 to 90/10. . 9. The cold seal adhesive according to claim 1, further comprising amorphous silica. 10. The cold seal adhesive according to claim 1, which further comprises a cationic polymer. 11. Claims 1 to 1 for ink jet recording.
The cold seal adhesive according to any of 0.