JPH0371882A - Desensitizing agent for pressure-sensitive copy - Google Patents

Abstract

PURPOSE:To enhance desensitizing effect, to eliminate transfer properties or permeability and to stabilize desensitizing effect even under environment of exposure or high temp. and high humidity by constituting the graft-polymerized aminostyrene compound contained in a desensitizing agent of a main chain containing a specific repeating unit and the specific side chain graft-polymerized with the amino group part of said main chain. CONSTITUTION:A desensitizing agent for pressure-sensitive copy is composed of at least one kind of a graft-polymerized aminostyrene compound consisting of a main chain and the side chain graft-polymerized therewith. The main chain is constituted of a repeating unit represented by general formula I and the side chain is graft-polymerized with the amino group part of the repeating unit and composed of at least one member of an alkylene oxide unit represented by general formula II and a styrene oxide unit. This compound has blocking resistance and migration resistance preventing such a phenomenon that the desensitizing agent is diffused and transferred to the place desired to be developed of copy paper to exert desensitizing effect thereon and the desensitizing agent excellent in desensitizing effect such as the prevention capacity of color development and the erasing capacity of a developed color can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a desensitizer for pressure-sensitive copying that is used in pressure-sensitive copying paper and has an excellent desensitizing effect. More specifically, the present invention provides a pressure-sensitive copying material having a pressure-sensitive color-forming layer containing an electron-donating colorless dye precursor and an electron-accepting color developer capable of reacting with the colorless dye precursor to develop color. The present invention relates to a desensitizer for pressure-sensitive copying that can suppress or prevent the color-forming reaction of the above-mentioned colorless dye and electron-accepting color developer even when the colorless dye comes into contact with the electron-accepting color developer.

(Prior Art) In general, pressure-sensitive copying paper uses colorless dye precursors such as phenylmethane compounds, triarylmethane compounds, xanthine compounds, thiazine compounds, and spiro compounds that have electron-donating properties in a non-volatile manner. This solution is subjected to coacelbasigon method, 1n-situ polymerization method,
Alternatively, an upper paper prepared by encapsulating the microcapsules in microcapsules by applying a microcapsule method such as an interfacial polymerization method onto a sheet-like support such as paper, solid acids, various phenolic compounds, etc. A base paper made by applying an electron-accepting color developer such as a novolac type phenolic resin, an aromatic carboxylic acid and its resin, or a polyvalent metal salt thereof to a sheet-like support such as paper. It is composed of a combination of By stacking the top paper and the bottom paper so that their coated surfaces face each other and applying pressure by writing or using a typewriter, the microcapsules are destroyed at the pressure area of the top paper, and the microcapsules are injected into them. A desired colored image can be formed by causing the contained colorless dye precursor to react with the color developer coated on the bottom paper.

Further, a plurality of inner sheets made by applying a color developer on the surface of the sheet-like support and microcapsules containing a colorless dye precursor on the back side are used between the upper sheet and the lower sheet. This makes it possible to make multiple copies. Furthermore, if a layer of microcapsules containing a colorless dye precursor solution and a layer of a color developer are laminated or simultaneously coated on one side of the support, even a sheet of paper can develop color as a self-contained paper. An image can be formed.

Desensitizers are used to suppress or prevent color development by pre-coating the parts of the developer-coated surface of pressure-sensitive copying paper that do not need color development, or to partially cover already colored images to erase the color of the developed images. It is a drug used for this purpose.

Conventionally known desensitizing agents for desensitizing inks include, for example, cationic quaternary ammonium salts, aliphatic amine acetates, higher aliphatic amines, and the like described in Japanese Patent Publication No. 33-3921.
and oxazoline derivatives, higher amines, higher diamines, and organic bentonites described in Japanese Patent Publication No. 44-27255, polyoxyethylene alkyl esters, polyoxyethylene alkyl ethers, and polyoxyethylene alkyl phenol ethers described in Japanese Patent Publication No. 47-38201. , poly T-alkyl glutarate described in Japanese Patent Publication No. 49-4484, Japanese Patent Publication No. 49-230
Ethylene oxide adducts of polyalkylene polyamines described in No. 08, propylene oxide adducts of alkylene diamines described in Japanese Patent Publication No. 49-23850,
Alkylene oxide adducts of cyclic structure-containing diamines or polyamines as described in Japanese Patent Publication No. 50-14571, propylene oxide adducts of tertiary amines as described in Japanese Patent Publication No. 50-29365, polyamides as described in Japanese Patent Publication No. 55-1919. Pyropylene glycol, Special Publication 1984-4
A compound obtained by adding alkylene oxide and/or styrene oxide to an alkylphenol or a polycondensate of alkylphenol and formaldehyde described in JP-A-2479, an alkylene oxide compound of an amide compound described in JP-A-56-142093, JP-A-57-
Addition product of rosin or carboxyl group-containing modified rosin and alkylene oxide described in JP-A No. 75894, higher fatty acid ester of polypropylene glycol and ethylene oxide adduct described in JP-A-57-93195, JP-A-57-95493 Alkylene oxide or styrene oxide adducts of resin-reduced alcohols described in Japanese Patent Application Publication No. 1982-138977, glycerin-propylene oxide co-adducts described in JP-A-57-138977, Japanese Patent Publication No. 57-138977,
Alkylene oxide adducts of polyamines described in B-38119, alkylene oxide adducts of rosin alcohols described in JP-A-58-51183, and alkylene oxide adducts of rosin amines, and alkylene oxide adducts of rosin amines as described in JP-A-58-98282. Amine-based polyoxybutylene propylene copolymer polyols and adducts of rosin amine and alkylene oxide or styrene oxide described in Japanese Patent Publication No. 63-41750 are known.

These desensitizers are mixed with vehicles and pigments known in the printing ink technical field and used in various printing methods (flexo,
(gravure printing, letterpress printing, offset printing, silk screen printing, etc.), and use this as a desensitizing ink on the developer side of the bottom paper and middle paper, or on the coated side of self-contained paper. Print where necessary.

In line with the above-mentioned usage patterns, desensitizers are required to have high ability to prevent color development and erase colors, as well as to be able to create desensitizing inks with printability suitable for various printing methods. , and that after being applied to pressure-sensitive copying paper, it does not cause discoloration or degeneration such as yellowing, and the desensitizer does not diffuse or migrate and exert a desensitizing effect on areas where coloring is desired. It will be done.

[Problem to be solved by the invention]

As mentioned above, the present invention enables the adjustment of desensitized inks with printing suitability suitable for various printing methods, that is, fluidity, interfacial suitability, and drying properties, and yellowing after printing on pressure-sensitive copying paper. It has resistance to coloring and denaturation, etc., and has anti-blocking properties to prevent the desensitizer from diffusing and migrating and exerting a desensitizing effect to the desired coloring part of the copy paper.
The object of the present invention is to provide a new desensitizer for pressure-sensitive copying that has migration resistance and extremely excellent desensitizing effects such as color development prevention and erasing ability.

[Means and actions to solve the problem]

The desensitizer for pressure-sensitive copying of the present invention is composed of at least one graft-polymerized aminostyrene compound consisting of a main chain and a side chain graft-polymerized to the main chain, and the main chain is conjugated with the following (1): k represents 0 or an integer 1, n represents an integer from 3 to 75, and m represents O or an integer from 1 to 320. ] The side chain is graft-polymerized to the amino group portion of the repeating unit, and the following - conjugation (■ ): [However, in the above formula, R' represents a lower alkyl group having 1 to 2 carbon atoms, and R2 and R3 each independently have a hydrogen atom and 1 to 4 carbon atoms. Represents one member selected from the group consisting of lower alkyl groups, and R4 and Rs each independently represent a hydrogen atom,
Methyl group, phenyl group, chlorine atom, cyano group, acetoxy group, methoxycarbonyl group, carboxy group, vinyl group, and 6 [However, in the above formula, R6 is from the group consisting of a hydrogen atom, a methyl group, and a phenyl group. Represents one selected member, l is 2
It is characterized in that it consists of at least one member of an alkylene oxide unit and a styrene oxide unit represented by ], which represents an integer of 20 to 20.

The unreacted active hydrogen atom of the Ajuno group of the repeating unit of the above formula (1) may be substituted with an alkyl group.

The graft-polymerized aminostyrene compound contained in the desensitizer of the present invention is composed of a main chain comprising a repeating unit of formula (I) and a side chain of formula It is what it is.

The repeating units constituting the main chain are formed from aminostyrene compound polymerized units of the following formula %) and vinyl group-containing compound polymerized units of the following formula 4 (-CI(, -G+- 5). However, if a vinyl group-containing compound is copolymerized, the polymerized unit of a vinyl group-containing compound may not necessarily be included.
There are advantages such as a decrease in viscosity and prevention of gelation due to the lengthening of the distance between J.

Compounds that can be used as polymerization components forming the main chain include aminostyrene, N-methylaminostyrene, N-ethylaminostyrene, N-propylaminostyrene, N-isopropylaminostyrene, and N-butylaminostyrene. , N-isobutylaminostyrene, vinylbenzylamine, p-vinylbenzylamine, p-vinylbenzylmethylamine, p-vinylbenzylethylamine, p-vinylbenzylpropylamine, p-vinylhensylisopropylamine, p- Vinylbenzylbutylamine, p-vinylbenzylisobutylamine, vinylphenethylamine, p-vinylphenethylmethylamine, p-vinylphenethyl ethylagon, p-vinylphenethylpropylamine, p-vinylphenethylisopropylamine, p-vinylphenethylbutylamine, Examples include P-vinylphenethylisobutylamine. In addition, other substituents on the benzene ring of the anostine compound, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, nitro group, amino group, hydroxyl group, carboxy group, ester group, acyl group,
There is no problem even if it is substituted with a cyano group, imino group, halogen group, etc. In addition, examples of vinyl group-containing compounds for forming the main chain together with an aminostyrene compound include styrene, α-methylstyrene, vinyl chloride, vinylidene chloride, acrylonitrile, vinyl acetate, methacrylic acid, methyl methacrylate, acrylic acid, and acrylic acid. Examples include acid methyl, butadiene, isoprene, etc., and it is possible to use one or more of these vinyl group-containing compounds. The main polymer component for forming the main chain is an aminostyrene compound, and if necessary, a vinyl group-containing compound may be added as another component in an amount of 0 to 90% by weight based on the total components.
, preferably 40 to 75% by weight.

The polymerization degree of the aminostyrene compound polymer unit in the main chain is 3 to 75. If the polymerization degree is less than 3, the desensitizing effect will be insufficient, and if the polymerization degree is greater than 75, the viscosity will be excessive, and the ink will be There are disadvantages such as making it difficult to The copolymer that makes up the main chain has a relatively high molecular weight,
The average molecular weight thereof is preferably 400 to 1000, more preferably 400 to 2,500.

In the amino group portion of the main chain repeating unit (formula (I)) (I
Examples of the alkylene oxide and styrene oxide used to form the graft chain of formula I) include ethylene oxide, propylene oxide, and styrene oxide. The degree of polymerization (1) of the graft polymer chain is 2
-20, preferably about 4-10.

If the degree of polymerization (1) of the graft polymer chain is less than 2, the desensitizing effect will be insufficient, and if it exceeds 20, the viscosity will be too high, making it difficult to form into an ink.

If necessary, after adding alkylene oxide and/or styrene oxide as a graft chain to the amino group portion of the main chain, unreacted amino groups of the repeating unit of formula (1) above are added to increase hydrophobicity. A tertiary amine may be generated by reacting an alkyl halide with an active hydrogen atom and substituting this with an alkyl group. The alkyl halide that can be used in this alkylation reaction is represented by the following general formula (tl[).

R-X(III) (wherein R represents an alkyl group having 1 to 6 carbon atoms, and X represents (l or Br), Before addition to the moiety, the active hydrogen of the amino group is treated with an alkyl halide to convert the amino group into a secondary amine or tertiary amine, and then
There is no problem in graft polymerizing alkylene oxide and/or styrene oxide to this. In this case, the number of moles of alkylene oxide and/or styrene oxide added to the number of moles of amino group is
By setting the amount to 0 to 1.8 mol, preferably 0.2 to 1 mol, it is possible to prevent the graft chains from coming too close to each other, thereby lowering the viscosity of the desensitizer and improving fluidity. and can prevent gelation.

The desensitizer of the present invention may have physical properties such as viscosity and hydrophobicity changed depending on the purpose of use, and for this purpose, the desensitizer contains a vinyl group-containing compound bonded to the aminostyrene compound in the main chain copolymer. The above physical properties can be adjusted by changing the ratio, or by changing the number of moles of alkylene oxide and/or styrene oxide added to the number of moles of the amino group and the degree of polymerization.

In order to produce a desensitizing ink for pressure-sensitive copying using the desensitizer of the present invention, (1) a pigment, (2) a vehicle, and (3) a desensitizer may be blended. In addition, solvents such as glycols and alcohols, deterioration inhibitors, fluorescent whitening agents, paraffin wax for improving abrasion resistance, drying oils such as linseed oil, tung oil, and dice oil, and cottonseed oil. One or more selected from semi-drying oils such as , rapeseed oil and rice bran oil may be used in combination, and other types of desensitizer compositions may also be used in combination.

Pigments used in desensitizing inks are mainly used to adjust printability, whiteness, opacity, mattness, and viscosity of desensitizing inks, and include titanium oxide, zinc oxide,
barium sulfate, magnesium hydroxide, calcium carbonate,
Inorganic pigments such as magnesium carbonate and silicon dioxide,
Plastic pigments such as urea resin, melamine resin, and styrene resin are used.

A desensitizing ink vehicle is a component that serves to uniformly disperse pigments, give fluidity to the ink, and fix pigments, etc. to the printing surface.It is usually made from solvents and resins, and contains vegetable oils, mineral oils, and linseed oils. Solvents such as oil, ketone resins, polyamide resins, maleic acid resins, phenolic resins, epoxy resins, fumar resins, urea resins, melamine resins, alkyd resins, acrylic resins, nitrocellulose, methylcellulose, butyral resins, rosin i-based phenolic resins, Polymer compounds such as vinyl resin, casein, and gelatin are used.

Next, the color developer that can be used in this pressure-sensitive copying material is an active viscosity substance such as acpulgite, acidic viscosity, or bentonite, or an acidic organic compound or its polyvalent metal salt, such as Japanese Patent Publication No. 42-20144. P-phenylphenol novolak resin disclosed in
Novolac-type phenolic resins such as octylphenol novolak resin, phenolic resins such as phenolacetylene resin, and polyvalent metal salts thereof, or Japanese Patent Publication No. 10856/1985, Japanese Patent Publication No. 2517/1986
Benzoic acid, nitrobenzoic acid, p-te as described in Japanese Patent Publication No. 49-55410, etc.
rt-Butylbenzoic acid, 4-methyl-3-nitrobenzoic acid, P-isopropylbenzoic acid, 2,5-dinitrobenzoic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 2-hydroxy-1-benzyl -3-naphthoic acid,
1-benzoyl-2-hydroxy-3-naphthoic acid, 3
-hydroxy-5-cyclohexyl-2-naphthoic acid,
Salicylic acid, 5-tert-butylsalicylic acid, 3-phenylsalicylic acid, 3-cyclohexylsalicylic acid, 3
-Methyl-5-tert-butylsalicylic acid, 3,5-
Di-tert-butylsalicylic acid, 3-methyl-5-benzylsalicylic acid, 5-cyclohexylsalicylic acid, 3
-Methyl 5-isoamylsalicylic acid, 3,5-di-5e
e-Butylsalicylic acid, 3-phenyl-5-(α.

α-dimethylhensyl)salicylic acid, 3-cyclohexyl-5-(α,α-dimethylbenzyl)salicylic acid, 3
-(α,α-dimethylbenzyl)5-methylsalicylic acid, 3,5-di-cyclohexylsalicylic acid, 3,5-di(α-methylbenzyl)salicylic acid, 3,5-di(
Aromatic carboxylic acids such as α,α-dimethylbenzyl)salicylic acid, 3-(α-methylbenzyl)-5-(α,α-dimethylbenzyl)salicylic acid, 4-methyl-5-cyclohexylsalicylic acid, and these compounds. Polyvalent metal salts, or metal salts of oligobenzylated aromatic hydroxycarboxylic acids as described in JP-A-63-132857, or JP-A-63-132857.
Polyvalent metal salt of Maunacarboxy-modified terbenfpenol resin disclosed in No. 19486, or salicylic acid novolac resin (JP-A-48-8215), or JP-A-62-176875, JP-A-Sho. 63-53
Copolymers of salicylic acid and compounds such as alkoxyxylene, trialkylbenzene, or styrene derivatives, or polyvalent metal salts thereof, as disclosed in No. 092, JP-A No. 63-186729, etc. I can give it to you. These acidic substances alone
Alternatively, two or more types can be used in combination.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to Examples.

21 three-necked flasks equipped with a stirrer and a reflux condenser.
Charge 1"i1 of benzene, 30 g of straw nostyrene, and 30 g of styrene, replace the inside of the flask with nitrogen, add 2.5 g of azoisobutyronitrile as an initiator, raise the temperature inside the flask to 40°C, and then heat to 70°C. The temperature was raised to C. After reacting the reaction mixture for 6 hours at this temperature, it was cooled, reprecipitated in dehydrated methanol, and the precipitate was collected and vacuum dried. The average molecular weight of the aminostyrene-styrene copolymer was 2,400.

40g of the obtained aminostyrene-styrene copolymer was
1 The rear part of the vacuum was replaced with nitrogen, heated to 120"C, and then 60% of ethylene oxide was added to it.
g was gradually added under pressure to react.

Next, the produced ethylene oxide adduct was dissolved in benzene, and ethyl bromide was added to introduce an alkyl group into the unreacted active hydrogen of the amino group. The obtained aminostyrene-styrene copolymer-ethylene oxide graft polymer is
It was a pale yellow viscous liquid.

2゛, No. 1゛ Charge 1i of benzene and 50 g of aminostyrene into a 21 three-neck flask equipped with a stirrer and a reflux condenser, replace the inside of the flask with nitrogen, and add 2.5 g of azoisobutyronitrile.
g was added as an initiator, and the temperature in the flask was raised to 40 °C and then to 60"C. The reaction mixture was allowed to react at this temperature for 6 hours, and after cooling, the reaction product was transferred to the dehydrated It was reprecipitated in methanol, and the precipitate was collected and vacuum dried.The average molecular weight of the obtained aminostyrene polymer was 2,000.

40 g of the obtained aminostyrene polymer was placed in a 22 autoclave, the rear part of the vacuum was replaced with nitrogen, and the temperature was heated to 120°C.
After heating to , 60 g of ethylene oxide was gradually added under pressure to cause a reaction. The obtained aminostyrene polymer-ethylene oxide graft polymer was a pale yellow viscous liquid.

The aminostyrene polymer-ethylene oxide graft polymer obtained in Example 2 was reacted with ethyl bromide to add an alkyl group to the unreacted active hydrogen of the amino group. . The obtained product was a pale yellow viscous liquid.

1. A desensitizing ink with the following composition using the desensitizers of Examples 1 to 3 above. Made by Il.

The above components were mixed together, and the mixture was kneaded in a ball mill for 24 hours to produce an ink, which was coated on commercially available pressure-sensitive copying paper with RJ-2. Printing was performed using a mold printing tester (manufactured by Mei Seisakusho).

The desensitized ink was evaluated as follows.

1) Desensitizing effect: The desensitizing ability is tested by printing on a typewriter with the lower paper printed with desensitizing ink and the upper paper not printed on top of each other.

2) Penetration: Overlay the inner paper that is not printed with desensitizing ink on top of the inner paper that has been printed with desensitizing ink, and then layer the bottom paper that is not printed with desensitizing ink under the paper that is printed with desensitizing ink. , this laminate was heated to 40'C1 under a pressure of 500 g/cd.
After leaving it in an atmosphere of 70% RH for one week, take out the unprinted middle paper and the unprinted bottom paper, combine them with the top paper without desensitizing ink printing, and print on this with a typewriter to develop each color. tested for sex.

3) Transferability: Layer the developing sides of the bottom paper printed with desensitizing ink and the bottom paper without printing, and weigh 500 g.
After leaving it in an atmosphere of 40°C and 170% RH under pressure of /ctA for one week, take out the bottom paper that has not been printed with desensitizing ink, overlap it with the top paper that has not been printed, and print on a typewriter. Color development was tested.

4) Lightfastness test The bottom paper printed with the double-desensitized ink was tested using a weather meter (super long life weather meter).
After being exposed to light for 12 hours using a Suga Test Instruments (manufactured by Suga Test Instruments), desensitization ability and discoloration were examined.

5) Heat and humidity resistance: Lower paper printed with desensitizing ink at 70°C
After being left in an atmosphere of 180% RH for 24 hours, its desensitization ability and discoloration were examined.

Evaluation was performed on the following five levels.

Evaluation method [Effects of the invention] The desensitizer of the present invention has a high desensitizing effect on pressure-sensitive copying paper, has no transferability or permeability, and has an extremely stable desensitizing effect even under dawn light and high temperature environments. Therefore, it has extremely high practical effects.

The results of this test and the evaluation data of a commercially available desensitizing ink as a comparative example are shown in Table 1.

Table 1

Claims (1)

[Claims] 1. Consists of at least one graft-polymerized aminostyrene compound consisting of a main chain and a side chain graft-polymerized thereto, the main chain having the following general formula (I): ▲ Numerical formula, chemical formula, There are tables, etc.▼(I) [However, in the above formula, R^1 represents a lower alkyl group having 1 to 2 carbon atoms, and R^2 and R^3 each independently represent hydrogen. Represents one member selected from the group consisting of atoms and lower alkyl groups having 1 to 4 carbon atoms, and R^4 and R^5 each independently represent a hydrogen atom, a methyl group, a phenyl group, Chlorine atom, cyano group,
acetoxy group, methoxycarbonyl group, carboxy group,
Represents one member selected from the group consisting of a vinyl group and an isopropenyl group, k represents 0 or an integer 1, and n represents 3
It represents an integer of ~75, and m represents an integer of 0 or 1-320. ] It is composed of a repeating unit represented by the following formula (II), and the side chain is graft-polymerized to the amino group portion of the repeating unit, and the following general formula (II) : ▲There are mathematical formulas, chemical formulas, tables, etc.▼(II) [However, in the above formula, R^6 represents a member selected from the group consisting of a hydrogen atom, a methyl group, and a phenyl group, and l is 2 to Represents an integer of 20. ] A desensitizing agent for pressure-sensitive copying, comprising at least one member of an alkylene oxide unit and a styrene oxide unit represented by the following. 2. The desensitizer according to claim 1, wherein the unreacted active hydrogen atom of the amino group of the repeating unit of formula (I) is substituted with an alkyl group.