JPS6047080A - Releasable white and black india ink composition and water-dispersible resin for said composition - Google Patents

Abstract

PURPOSE:To provide a white or black India ink compsn. which is readily erasable after use, prepd. by adding a black or white colorant to a specified film- forming substance. CONSTITUTION:The releasable white or black India ink compsn. is prepd. by adding a white or black colorant to a liquid substance capable of forming a film which makes writing possible and is readily peeled off upon drying [e.g. water- dispersible resin obtained from a monomer with polymerizable unsatd. bonds, such as (meth)acrylic ester]. The compsn. can be used in the same way as with conventional white or black India ink and the writing can be peeled off after drying. The water-dispersible resin should pref. have a solid content of 10-70 wt%, a viscosity of 10-10,000cps (BH type rotation viscometer, 20rpm at 25 deg.C), a pH of 2-10 and an average particle diameter of 0.01-0.6mu. When a (co)polymer for the resin has a glass transition point (Tg) of 229-303, a compsn. is obtained which shows good releasability and optimum tackiness throughout the year.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a novel peelable white ink composition that can be used in the same way as conventional self-injection and ink ink and can be easily peeled off after use (after drying), and an aqueous dispersion for the composition. Regarding resin.

Sumi ink is primarily used to write letters and pictures on blank paper with a writing instrument such as a brush, but it is also used to write letters and pictures on major signboards (display boards). For example, it is used to write letters on funeral signboards.

However, since ordinary India ink is not designed with the assumption that it will be erased after writing, it has problems such as inconvenience depending on the use.

For example, when ink is applied to a funeral signboard, funeral signboards are usually made from a single piece of expensive Japanese cypress, so the letters written in ink must be erased because they need to be used repeatedly. In this case, it takes effort to cut the surface of the cypress board with a plane, etc., in a place where ink and juice do not seep, and the cutting process thins the thickness of the cypress board, so it is necessary to repeat the process. There are problems such as making it unusable. In addition, when ink is applied to a synthetic resin board that has virtually no water absorption, the ink ink can be erased after use, but ink has the property of being difficult to write on boards that have no water absorption. Moreover, the erasing process was troublesome because it caused secondary contamination with ink. Furthermore, ordinary ink is
Because it has very poor water resistance, letters written with ink were easily smeared when exposed to rainwater.

In addition, as a method of repeatedly using the display board by writing characters, etc. on the display board, etc. and erasing the characters, etc. after use, it is possible to use the display board, etc. on the welcome display board of hotels, etc., and the display board that displays the general name, etc. There is a method of writing characters etc. on the black display board by hand and washing off the handwritten characters after use. However, using this method requires troublesome work such as washing off the self-written characters and drying the display board, and furthermore, since the self-written characters are not substantially water resistant, it is difficult to use the self-written characters 1. Signs shall not be displayed in areas exposed to rain.

In view of the ridges, the inventors of the present invention have conducted various studies with the aim of providing white ink and ink that can be easily erased after use. - It has been discovered that a India India ink composition can achieve the above objectives.

The present invention was made based on the above findings, and is made by adding a coloring agent that colors the film black or white to a liquid film-forming substance that forms a film that is writable and peelable after drying. The present invention provides a peelable white/India ink composition and a water-dispersible resin for the composition.

In addition, in detail, the peelable white/India ink composition of the present invention is
1] It refers to a self-injection composition or a peelable India ink composition, and the former composition is formed when a white pigment (white pigment) is used as a colorant; The latter composition is formed when a black pigment) is used.

The peelable white/India ink composition of the present invention will be described in detail below.

The most preferred example of the liquid film-forming substance that forms the peelable white/India ink composition of the present invention is a water-dispersed resin obtained from a monomer having a polymerizable unsaturated bond.

The monomer having a polymerizable unsaturated bond for obtaining the above-mentioned water-dispersed resin is a chemical substance containing one or more double bonds having normal radical polymerizability, and preferable specific examples thereof include, for example, (meth)acrylic acid ester monomer,
Examples include vinyl ester monomers, aromatic birunimonomers, acrylonitrile monomers, and the like.

Examples of (meth)acrylic acid ester monomers include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, butyl methacrylate, and propyl methacrylate. , butyl methacrylate, 2-ethylhexyl methacrylate, etc., and among these, preferred are ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methacrylate, and the like.

Examples of vinyl ester monomers include vinyl acetate, vinyl propionate, vinyl butyrate, and vinyl varsate. Among these, vinyl acetate and vinyl varsatate are preferred.

Examples of aromatic vinyl monomers include styrene, methylstyrene, dimethylstyrene, ethylstyrene, butylstyrene, benzylstyrene, chlorostyrene, etc. Among these, preferred are styrene, methylstyrene, etc. be.

Examples of the acrylonitrile monomer include acrylonitrile, methacrylonitrile, and the like, with acrylonitrile being preferred.

When obtaining the water-dispersed resin in the present invention, each of the above-mentioned monomers may be used alone or in combination of two or more.

Moreover, other monomers can also be used in combination with the above-mentioned monomers. Other monomers that can be used include, for example:
Examples include ethylenically unsaturated monomers having a carboxyl group, crosslinkable monomers, (meth)acrylic acid amide monomers, halogenated vinyl monomers, olefin monomers, and the like.

Examples of the ethylenically unsaturated monomer having a carboxyl group include maleic acid, fumaric acid, maleic anhydride,
Examples include dicrotonic acid, acrylic acid, methacrylic acid, itaconic acid, etc., but acrylic acid, methacrylic acid, itaconic acid, etc. are preferably used.

Examples of the crosslinkable monomer include divinylbenzene, diallyl phthalate, triallyl cyanurate, triallyl isocyanurate, ethylene glycol dimethacrylate, hexylene glycol dimethacrylate, ethylene glycol diacrylate, hexylene glycol diacrylate, Examples include glycidyl acrylate and glycidyl methacrylate.

Other monomers include acrylamide, methacrylamide, N-methylol acrylamide, N
-Methylolmethacrylamide, N,N' dimethylacrylamide, hydroxyethylacrylamide,
Dimethylaminoethyl methacrylate, tertiary
Butylaminoethyl methacrylate, aminoethyl acrylate, amine edyl methacrylate, vinyl pyridine, vinyl chloride, vinylidene chloride, vinyl fluoride,
Examples include ethylene, propylene, and Bukugen.

In order to obtain the water-dispersed resin of the present invention, one or more of the above monomers may be selectively used in any combination; is 100 parts by weight of butyl acrylate 1iff1 and 15 to 200 parts by weight, preferably 20 to 150 parts by weight, more preferably 20 to 150 parts by weight of acrylonitrile monomer, methyl methacrylate monomer, or styrene monomer. 12
Preferably, a water-dispersed resin obtained by using a combination of
Particularly preferred is a water-dispersed resin obtained by using a combination of butyl acrylate monomer and acrylonitrile monomer in the above weight ratio.

Further, as the water-dispersed resin in the present invention, any water-dispersed resin can be used as long as it is a water-dispersed resin obtained from the above-mentioned monomers, but generally the above-mentioned monomers are homopolymerized or copolymerized under emulsion polymerization conditions. A water-dispersed resin obtained by a method of forming the resin by a method of forming the resin, or a method of solution-polymerizing the above-mentioned combination monomers and then emulsifying them is used. Preferably, a water-dispersible resin obtained by the former method is used.

In addition, the filtrate dispersion resin used in the present invention generally has a solid content, although not necessarily limited by its viscosity, solid content, pH, glass transition temperature (Tg), molecular weight, average particle diameter, etc. (JIS-6823) Concentration is 10~
70% by weight, preferably 20 to 70% by weight, particularly preferably 30 to 65% by weight, viscosity (BH type rotational viscometer 2Or
pm 25°C) is 10 to 10,000 cps, preferably 500 to 8,000 cps, particularly preferably 500 to 8,000 cps
5000cps, pH is 2-10, preferably 3
-9, particularly preferably 4-9, average particle diameter of 0.01-9
0.6μ, preferably 0.02 to 0.5μ, particularly preferably 0.05 to 0.5μ, and in particular, the solid concentration and viscosity are within the above-mentioned preferred ranges. It is possible to form a peelable mortar and India ink composition of the present invention of high quality. The resin concentration in the solid content of the water-dispersed resin is usually 99 to 90%, preferably 97 to 92%.

Further, the homopolymer or copolymer obtained from the monomers forming the water-dispersed resin in the present invention generally has a glass transition temperature (hereinafter abbreviated as Tg) of 229 to 303,
More preferably, a water-dispersed resin having a Tg of 233 to 283 is used, and by using a water-dispersed resin made of a homopolymer or a polymer having a Tg in the above range, it can be used throughout the winter and summer.
The releasable mortar of the present invention exhibits excellent releasability and hardness.
A black juice composition can be obtained. Note that the Tg is calculated using the following formula.

TH calculation formula Tg and Tgn are expressed in absolute temperature. Wn indicates the weight fraction of each monomer component of the polymer. In addition, T of the polymer of each monomer
-g is shown in Table 1 below.

Table-1 Tg of polymer of each monomer In addition, the emulsion polymerization method, which is a preferred polymerization method when obtaining the water-dispersed resin used in the present invention from the monomers, can be carried out according to a known method. I can do it. That is, this emulsion polymerization can be carried out in an aqueous medium in the presence of a catalyst and in the coexistence of a surfactant and/or a protective colloid.

The surfactants used in the above emulsion polymerization include anionic surfactants such as sodium oleate,
Semi-hardened beef tallow soda, fatty acid salts such as potassium oleate, lauryl sulfate ester soda, higher alcohol sulfate ester soda, higher alcohol sulfate ester salts such as lauryl alcohol sulfate ester triethanolamine salt, lauryl alcohol sulfate ester ammonium salt, dodecylbenzenesulfate Alkylbenzene sulfonates such as sodium fluoroate, alkylnaphthalene sulfonates such as sodium alkylnaphthalenesulfonate, formalin condensates of naphthalene sulfonate, dialkyl sulfosuccinates such as sodium dioctyl sulfosuccinate, and alkyl phosphates. , and those obtained by adding ethylene oxide to the above-mentioned anionic surfactants4, which may be used alone or in combination of two or more6. As a surfactant, Noeone type surfactant, for example, polyoxyethylene alkyl ester such as polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, etc. Polyoxyethylene alkyl esters such as polyoxyethylene monolaurate, polyoxyethylene monostearate, and sorbitan monolaurate, sorbitan esters such as sorbitan monostearate, polyoxyethylene sorbitan Polyoxyethylene sorbin alkyl' esters such as monolaurate, polyoxyethylene polypropylene brochloride polymers, polyethylene glycols, etc. can also be used in combination.

Furthermore, amphoteric surfactants such as betaine-type amphoteric surfactants such as dimethylalkyl betaine, lauryl betaine, and stearyl betaine, small amounts of cationic surfactants, etc. can also be used in combination.

Examples of protective colloids used in the emulsion polymerization include partially saponified polyvinyl alcohol, completely saponified polyvinyl alcohol, modified polyvinyl alcohol, cellulose derivatives such as hydroxyethyl cellulose, hydroxypropyl cellulose, and carboxymethyl cellulose salts, and its salts, and natural polysaccharides such as guar gum. These can be used alone or in a combination of several types.

Furthermore, the catalysts used in the above emulsion polymerization include:
Examples include persulfates such as ammonium persulfate, potassium persulfate, and sodium persulfate; hydroperoxides such as hydrogen peroxide, tert-butyl hydroperoxide, and cumene hydroperoxide; preferred are persulfates and persulfates. Hydrogen oxide can be exemplified.

Further, as the polyvinyl alcohol used as the protective colloid, anionized polyvinyl alcohol is preferably used in an amount of, for example, 1 to 10% by weight, more preferably 0.5 to 5% by weight, based on the total amount of monomers. This is a preferred embodiment in order to obtain physical properties such as improving the leveling property when applying the ink ink composition of the present invention, increasing the strength of the film when peeling, and making it easy to peel even a thin film. This anionized polyvinyl alcohol can be used, for example, by combining an alkali olefin sulfonic acid salt and vinyl acetate in the presence of an alcohol solvent such that the content of the alkali olefin sulfonic acid salt is 0.5 to 7 mol%. Examples include modified polyvinyl alcohol obtained by saponifying a polymerized copolymer, and commercially available products include Goselan L-3266 (saponification degree 86-89%, polymerization degree 250-89%).
300, manufactured by Nippon Gosei Kagaku Kogyo @).

Further, during emulsion polymerization, a reducing agent may be used in combination, if desired. Examples include reducing organic compounds such as ascorbic acid, tartaric acid, citric acid, and glucose, sodium thiosulfate, sodium sulfite, sodium bisulfite, and sodium metabisulfite.

The reaction temperature in emulsion polymerization can be selected as appropriate, and examples thereof include temperatures of about 40 to about 90°C. During the reaction, the entire amount of a given surfactant can be added to the reaction system, but it is also possible to add a part to the reaction system in advance to start the reaction and then add the rest continuously or at intervals during the reaction. It can also be added in portions, and the latter is preferred. Further, each monomer can be added all at once, added in portions, or added continuously, but it is preferable to add them continuously from the viewpoint of reaction control.

In addition to the above-mentioned surfactants and catalysts, pH regulators, polymerization degree regulators, antifoaming agents, and the like can be added as appropriate during emulsion polymerization.

A preferred composition of the peelable ink composition of the present invention is to use the monoaqueous dispersion resin obtained as described above as a film-forming substance, add a black pigment or a white pigment as a coloring agent, and further add Preferably, it contains the following additives, and the water-dispersed resin in the peelable India ink composition is preferably 80 to 99% by weight, more preferably 85 to 97% by weight.

Examples of the black pigment include carbon blank, iron black, diamond blank, etc., and examples of the white pigment include titanium oxide, zinc white, lithopone, zinc sulfide, basic lead sulfate, etc. The releasable white color of the present invention
It is added to the ink composition in an amount of 1 to 20% by weight.

Further, the peelable white/black ink composition of the present invention preferably contains an amide compound, an anionic surfactant, and a polyhydric alcohol as additives in addition to the water-dispersed resin described above.

The above-mentioned amide compound has the function of imparting releasability to the removable white/ink composition of the present invention without leaving any haze on the substrate after peeling, and the amide compound includes:
For example, organic carboxylic acid amides such as stearic acid amide, ricinoleic acid amide, oleic acid amide, lauric acid amide, ethylene bisamide such as ethylene bisstearic acid amide, alkyl sulfanamide carboxylic acid such as stearin sulfanamide carboxylic acid, Examples include salts thereof, preferably stearic acid amide, sodium alkyl sulfanamide carboxylate, etc., and the amount used is preferably 0.1 to 8 weight by weight in the peelable white/India ink composition of the present invention. %, particularly preferably 0.5-6% by weight
, more preferably 0.5 to 4% by weight.

In addition, the anionic surfactant mainly functions to impart releasability to the peelable white/India ink composition of the present invention after a long period of time, and Examples of the surfactant include anionic surfactants used during emulsion polymerization to obtain the water-dispersed resin, preferably sodium uralyl sulfate, sodium dodecylbenzenesulfonate, etc. The amount is preferably 0 in the peelable white/India ink composition of the present invention.
．． 01 to 10% by weight, particularly preferably 0.05 to 7% by weight, and even more preferably 0.1 to 3% by weight.

Moreover, the polyhydric alcohol exhibits a function of imparting good releasability to the releasable white/India ink composition of the present invention, mainly when heated (solar heat or heating during drying). Examples of the polyhydric alcohol include ethylene glycol-mipropylene glycol, glycerin, catechol, butanediol, bentanediol,
Examples include erythritol, glycerin monoalkyl ester, polyethylene glycol, glycerin, etc., and the amount used thereof is preferably 0.01 to 5% by weight, particularly preferably 0.05% by weight, in the peelable white/India ink composition of the present invention. ~3
% by weight, more preferably 0.1 to 2% by weight.

Further, the amide compound, anionic surfactant, and polyhydric alcohol are mixed in a ratio of 100:5:1 to 100:50:30.
It is preferable to use it at a weight ratio of 100% from the viewpoint of peelability, cloudiness of the peeled surface, etc.

In addition to the above-mentioned additives, the peelable white/black ink composition of the present invention also contains waxes, film-forming aids, antifoaming agents, plasticizers, thickeners, pH regulators, preservatives, antifungal agents, An antifreeze agent or the like can be added as appropriate.

Wax refers to natural or synthetic wax, paraffin, and wax, such as natural animal and plant whale oil, carnauba wax,
Examples include beeswax, mutton fat, candelilla wax, monk wax, Chinese wax, wood wax, petroleum-based paraffin wax, petrolatum, liquid paraffin, synthetic waxes such as polyethylene and polypropylene, and glycerin fatty acid esters. Preferred examples include liquid paraffin and synthetic wax emulsion. The wax has the effect of further increasing the peelability after drying of the peelable white/India ink composition of the present invention, and the amount used is about 0 to 6 parts by weight, preferably 0 to 100 parts by weight of the water-dispersed resin. , 5 to 4 parts by weight.

Examples of film forming/forming aids include methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl carpitol, ethyl carpitol, butyl carpitol, dibutyl carpitol, methyl cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, methyl carpitol acetate-1・Ethyl carpitol acetate, butyl carpitol acetate, benzyl alcohol, benzyl acetate, toluene, xylene,
Examples include petroleum hydrocarbons, texanol, etc., preferably butyl carpitol, butyl cellosolve acetate,
butyl carpitol acetate, texanol, etc., which have the effect of lowering the film formation temperature when the peeling property/ink ink composition of the present invention forms a film, and the amount used is generally about 100 parts by weight per 100 parts by weight of the water-dispersed resin. 0.5 to 15 parts by weight, preferably about 1 to 8 parts by weight. Examples of antifoaming agents include silica silicone, silicone, metal soap, fatty acid amide, fatty acid ester, polyether, polyglycol, organic phosphoric acid, higher alcohol, sulfonated fatty acid, and oil-soluble. Examples include polymer-based materials, preferably silicone-based, silica-silicone-based, metal soap-based, fatty acid amide-based, or composite systems thereof. , and has a defoaming effect during application, etc., and the amount used is generally 0.00 parts by weight per 100 parts by weight of the water-dispersed resin.
001 to 1 part by weight.

The peeling property/India ink composition of the present invention has a ridge-like composition, and the composition of each component in the peeling property/India ink composition of the present invention is summarized as follows.

Part by weight Water-dispersed resin 85 to 97 Amide compound 0.5 to 6 Anionic surfactant 0.1 to 3 Polyhydric alcohol 0.1 to 2 Film forming aid 0.8 to 8 Wax 0.4 to 4 Antifoaming Agent 0.001-1 Preservative 0.01-2 Thickener 0.01-5 Plasticizer O-2 Colorant (for black pigment) 1-10 〃 (for white pigment) 1-20 In addition to the above-mentioned water-dispersed resins, water-soluble substances are used as film-forming substances in the peeling property/black ink composition of the invention, and these water-soluble substances include carboxymethyl cellulose salt, hydroxyethyl cellulose, etc. , hydroxypropyl cellulose, etc. (7) C/L/Rose derivatives, partially saponified polyvinyl alcohol, completely saponified polyvinyl alcohol, modified polyvinyl alcohol, water-soluble acryl 1tkJ fat, polyacrylamide, polyvinylpyrrolidone, water-soluble Examples include polyester, water-soluble alkyd resin, etc., and in the release property/ink ink composition of the present invention using these water-soluble substances, the above-mentioned various additives that are added when using the above-mentioned water-dispersed resin are also added. It can be contained in accordance with the amount used above.

As seen from the ridges, the ink ink composition with peeling properties of the present invention can be used to write letters on designated signboards, display boards, etc. in the same manner as ordinary ink ink, and forms a releasable film after drying. Therefore, according to the peeling property/India ink composition of the present invention, if it becomes necessary to rewrite the characters on a signboard, display board, etc. after use, the characters can be erased by simply peeling off the film, and the book can be reused. It is possible to write new characters, etc. using the peeling property/ink ink composition of the invention, and therefore, signboards, display boards, etc. can be used repeatedly without the need for special work to rewrite the characters, etc. Can be done. Moreover, the peeling property/India ink composition of the present invention can be improved by selectively using various additives.
Characters with appropriate adhesion, appropriate gloss, and appropriate water resistance can be easily written on various boards such as wooden boards, synthetic resin boards, metal boards, etc., and can be easily peeled off without staining them. The composition can be used to form a film, and is particularly suitable for writing on funeral signboards, wedding display boards, welcome display boards, etc. in hotels, etc.

Examples of the peeling property/India ink composition of the present invention will be given below to specifically clarify the effects of the present invention.

Example 1 400 g of water was added to a 21-volume glass flask equipped with a stirrer.
Anion-modified poval (Goselan L-3266>5.
Add g and dissolve. On the other hand, in a surfactant aqueous solution obtained by dissolving 20 g of polyoxyethylene nonylphenyl ether (approximately 30 moles of ethylene oxide added) and 3 g of sodium dodecylbenzenesulfonate in 130 g of water,
Butyl acrylate 370 g, acrylonitrile 230 g
g and stirred to obtain a monomer mixture.

Next, after purging the inside of the flask with nitrogen, the monomer mixture and 50 g of a 4% ammonium persulfate aqueous solution were added to the aqueous solution in the flask while maintaining the reaction temperature at 70°C.
and 50 g of 4% sodium metabisulfite were added over 5 hours to effect emulsification and polymerization to obtain an emulsion with a solid content of about 50%. To 100 parts of the obtained emulsion were added 3 parts of sodium lauryl sulfanamide carboxylate, 1.8 parts of a 30% aqueous solution of sodium lauryl sulfate, 0.5 parts of ethylene glycol, 3 parts of black pigment (International Color Black, International Paint side layer), thickener,
Add adjustment water, viscosity 2700 cps, solid content approximately 47%
, a black ink composition with a pH of 6.2 was obtained.

The above India ink composition was applied to a plywood board formed by adhering a vinyl chloride resin film with a wood grain pattern to the surface, so that the total coating thickness was 200μ, and after heating and drying at 30°C for 2 hours, it was peeled off. When the resistance was measured, the peel resistance was 19
It was 5g/cm.

Further, the character "large" was written with a brush using the above India ink composition, and the writing feel, appearance after being left at room temperature for one day, and releasability were measured. The writing quality was extremely smooth and better than that of ordinary India ink, and the appearance of the characters had a suitable gloss.The character "Dai" could be easily peeled off without any resistance to peeling, and there was no residue left after peeling. Further, even when the surface of the plywood was wiped with a wet cloth after the letters "large" were peeled off, the black color did not come off, the letters did not disappear, or they did not smudge.

Example 2 400 g of water was added to a 28-capacity glass flask equipped with a stirrer.
Anion-modified poval (Goselanshi-3266) 5g
Add and dissolve. On the other hand, 370 g of butyl acrylate and 230 g of acrylonitrile were added to an aqueous surfactant solution obtained by dissolving 20 g of polyoxyethylene nonylphenyl ether (approximately 30 moles of ethylene oxide added) and 3 g of sodium dodecylbenzenesulfonate in 130 g of water. Add and mix with stirring to obtain a monomer mixture.

Next, after directly viewing the inside of the flask with nitrogen, 50 g of the monomer mixture, 50 g of 4% ammonium persulfate aqueous solution, and 50 g of 4% sodium metabisulfite were added to the aqueous solution in the flask while maintaining the reaction temperature at 70°C. The mixture was added over a period of time to effect emulsification and polymerization to obtain an emulsion with a solid content of approximately 50%. To 237,100 parts of the obtained emul were added sodium lauryl sulfanamide carboxylate, 3 parts of an equivalent mixture of liquid paraffin, 1.8 parts of a 30% aqueous solution of sodium lauryl sulfate, 0.5 parts of ethylene glycol, 3 parts of butylcarpitol, Add 1.0 part of tributoxyphosphate, 0.1 part of antifoaming agent, 0.1 part of preservative, 3 parts of black pigment (International Color Black, manufactured by International Paint), thickener, and adjusting water to adjust the viscosity. 2700cp
A black ink composition having a solid content of about 47% and a pH of 6°2 was obtained.

The above India ink composition was applied to a plywood board formed by adhering a vinyl chloride resin film with a wood grain pattern to the surface, so that the total coating thickness was 200μ, and after heating and drying at 30°C for 2 hours, it was peeled off. When the resistance was measured, the peel resistance was 10
It was 0g/cm.

Further, the character "large" was written with a brush using the above India ink composition, and the writing feel, appearance after being left at room temperature for one day, and releasability were measured. The writing taste was extremely smooth and better than that of ordinary India ink, and the appearance of the characters had a suitable gloss.The character "Dai" could be easily peeled off without any resistance to peeling, and there was no residue left after peeling. Also, characters.

Even when the surface of the plywood was wiped with a wet rag after peeling off the "large" mark, the black color did not come off, the letters did not disappear, or the letters did not appear.

Example 3 In a glass flask with a capacity of 21 and equipped with a stirrer, 400 g of water,
Anion modified poval (Goselanshi-3266) 2
0 g, 2 g of 30% aqueous solution of sodium lauryl sulfate salt
Add and dissolve. On the other hand, in 130 g of water, 5 g of polyoxyethylene nonylphenyl ether (approximately 30 moles of added ethylene oxide), 1 lauryl sulfate), 3
In the surfactant aqueous solution obtained by dissolving 20g of 0% aqueous solution,
Butyl acrylate 390'g, acrylonitrile 18'
Og.

Add a mixture of 30g of methyl methacrylate and mix with stirring.
A monomer mixture is obtained.

Next, after purging the inside of the flask with nitrogen, the monomer mixture and 50 g of a 4% ammonium persulfate aqueous solution were added to the aqueous solution in the flask while maintaining the reaction temperature at 70"C.
and 50 g of 4% sodium metabisulfite were added over 5 hours to effect emulsification and polymerization to obtain an emulsion with a solid content of approximately 50%.

To 100 parts of the obtained emulsion was added sodium lauryl sulfanamide carboxylate, equivalent amount tm of liquid paraffin Compound 2
．． 5 parts, 095 parts of Na dodecylbenzenesulfonate,
0.3 parts of ethylene glycol, 2 parts of butylcarpitol, 0.3 parts of triptoxyphosphate, 0.1 part of antifoaming agent
1 part preservative, 3 parts black pigment (International Color Black, manufactured by International Paint ■), thickener, and adjusting water, viscosity 3100 cps, solid content approximately 4
A India ink composition of 5% and pH 6.0 was obtained.

The peel resistance of the obtained India ink composition was measured in the same manner as in Example 1, and it was found to be 150 g/cm. Furthermore, when the character "dai" was written with a brush, the written character did not sag, had a smooth writing feel, and exhibited excellent releasability.

Example 4 In the same manner as in Example 2, except that 10 parts of 50% Tit)+ previously dispersed in water was used instead of 3 parts of the black pigment used in Example 2, and the amount of thickener was increased. Viscosity 48
A self-pouring composition was obtained with a solids content of 00 cps and approximately 58% solids.

The obtained self-administered composition was subjected to the same test as in Example 1. As a result, the peel resistance was 95 g/Cl11, which was good. Also, the result of writing the character "dai" with a brush is
Similar to Example 1.2, except for the difference between black and white, writing quality, gloss, and releasability were extremely excellent.

Example 5 Instead of 3 parts of the black pigment used in Example 3, 10 parts of a 50% TiOx aqueous dispersion previously dispersed in water was used,
A self-administered composition having a viscosity of 4500 cps and a solid content of about 57% was obtained in the same manner as in Example 3, except that the amount of the thickener was increased.

The obtained self-administered composition was subjected to the same test as in Example 1. As a result, the peel resistance was excellent at 125 g/cm. Furthermore, the results of writing the word "large" with a brush were similar to those in Example 1.2, with good writing quality, gloss, and releasability, except for the difference in whether it was black or white.

Examples 6 to 9 Example 1 except that the surfactant, resin composition, and blended additives during emulsion production were changed as shown in Table 1 below.
Various compositions were obtained in the same manner as (the M composition was
Each sample was subjected to the same test as in Example 1. The results are shown in Table 2 below together with the results of Examples 1-5 and Reference Examples 1-2.

The peelability in Table 2 was evaluated using a 10-point scale, with 10 indicating that the sample was easily and completely peeled off, and 1 indicating that the sample could not be peeled off. In addition, water resistance is evaluated using a 10-point system, and a score of 10 is given when the surface of the plywood with letters written on it is exposed to rain for 12 hours and no particular change is observed, meaning that the letters have lost their shape. The case is shown as 1. Table 2 also shows the Tg of the resin that is a component of the composition.

Reference Example 1 Commercially available Indian ink was applied to the plywood formed by adhering the vinyl chloride resin film with a wood grain pattern to the surface, which was used in Example 1, to a total thickness of 200μ, and was heated at 30°C. After heating and drying for 2 hours, an attempt was made to peel it off, but the film could not be peeled off.

In addition, I wrote the word "dai" with a brush using the above ink, and after leaving it at room temperature for a day, I observed its appearance. It was not shiny, and when I wiped it with a damp cloth, some of the letters disappeared, and the area around the letters disappeared. It became black and dirty and unreadable. The letter ``large'' cannot be removed, so I wiped it off vigorously with a rag, but a faint black mark of the letter ``large'' remained, and ink remained in the small dents that I could not remove. Therefore, the plywood used in the experiment could not be reused.

Reference Example 2 On the plywood used in Example 1, 10 parts of an aqueous dispersion of 50% TiO was added instead of 100 parts of the emulsion used in Example 2.
A soup stock composition with a solids content <60% obtained by adding the same amount of additives as in Example 2 except for excluding the black pigment was applied, and after sufficiently drying, it was peeled off. However, the film could not be peeled off. Also, using the above soup stock composition, write the word "dai" with a brush and write the name "Muro". IA After leaving it for one day, I observed the appearance, and found that the gloss was poor, and when I wiped it with a damp cloth, some of the letters easily disappeared, making it unreadable. However, it took effort to completely clean the plywood surface.

Table 1 Table 2

Claims (1)

[Scope of Claims] A peelable white ink composition comprising a liquid film-forming substance that forms a film that is writable and peelable after drying, and a coloring agent that colors the film black or white. thing. (2) The peelable white/India ink composition according to claim 11, wherein the film-forming substance is a water-dispersed resin obtained from a monomer having a polymerizable unsaturated bond. (3) The above-mentioned The monomer having a polymerizable unsaturated bond is selected from the group consisting of a (meth)acrylic acid ester monomer, an aromatic vinyl monomer, a vinyl ester monomer, and an acrylonitrile monomer. The removable white according to claim (2), which is one or more monomers,
Indian ink composition. (4) The film-forming substance is a water-dispersed resin obtained from a monomer having a polymerizable unsaturated bond, and contains an amide compound, an anionic surfactant, and a polyhydric alcohol. Range No. 1 (Releasable white/black ink composition according to item 11. (5) The water-dispersed resin has a glass transition temperature of 229
303. The peelable white/India ink composition according to claim (2). (6) The peelable white/India ink composition according to claim (2), wherein the water-dispersed resin contains a protective colloid. (7) The peelable white/India ink composition according to claim (6), wherein the protective colloid is anionized polyvinyl alcohol. (8) The peelable white/India ink composition according to claim (1), wherein the film-forming substance is a water-soluble substance. (9) A water-dispersed resin for releasable white/black ink compositions obtained from a monomer having a polymerizable unsaturated bond. Ql The monomer having the above polymerizable unsaturated bond is (meta)
Acrylic acid ester monomer, aromatic vinyl monomer,
The peelable white/India ink composition according to claim (9), which is one or more monomers selected from the group consisting of vinyl ester monomers and acrylonitrile monomers. Water-dispersible resin for use.