JPH11295915A - Emulsion for electrophotographic recording sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize an ink fixing property and water resistance equal to those of the case in which a solvent based coating material is used by controlling a glass transition temp. of the emulsion obtained by subjecting a specified monomer mixture to an emulsion polymerization within a specified range. SOLUTION: The emulsion is obtained by subjecting the monomer mixture containing 20-70 wt.% arom. vinyl monomers, 0.1-20 wt.% unsatd. carboxylic acid monomers and 79.9-10 wt.% the other polymerizable monomer to the emulsion polymerization, and its glass transition temp. is controlled to 10-60 deg.C Styrene and a styrene deriv., for example o-methylstyrene, etc., are exemplified as the arom. vinyl monomer. For example, acrylic acid, methacrylic acid, etc., are exemplified as the unsatd. carboxylic acid monomer, α,β-unsatd. monocarboxylate, etc., are exemplified as the other polymerizable monomer. A particle size of the emulsion is preferably 20-3000 nm and more preferably 20-800 nm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emulsion coated on the surface of an electrophotographic recording sheet in order to improve the ink fixing property of the sheet. More specifically, when the emulsion is applied to a base material for an electrophotographic recording sheet such as paper or PET film, the adhesiveness to the base material, the film forming property, the heat blocking property, the water resistance, and the electrophotographic method are good. The present invention relates to an emulsion for an electrophotographic recording sheet which improves the fixability of ink when an image is printed on the electrophotographic recording sheet.

[0002]

2. Description of the Related Art In recent years, with the improvement in electrophotographic printing technology of OA equipment such as (color) copiers and printers, and the reduction in sales prices, more precise, high-speed, multicolor electrophotographic printing has become popular. Workplaces and laboratories are becoming possible. In addition, the importance of presentations using an overhead projector (hereinafter abbreviated as OHP) in business activities, conference presentations, and the like has become increasingly important, and OHP sheets are often produced by electrophotographic printing.

[0003] In order to realize high quality image quality in electrophotographic printing, various improvements of a printing machine main body and improvements of inks used for printing are made every day. In addition, with respect to a printing material (electrophotographic recording sheet) that receives these inks, an ink-receiving layer such as a solvent-based polyester resin or an acrylic resin is provided on the electrophotographic recording sheet to enhance the ink fixing property, thereby improving image fixability. The device has been devised to improve the clarity and fidelity of the device.

[0004] However, replacement of solvent-based materials with water-based materials has been accelerated from the viewpoint of global environmental problems and resource saving in recent years. For example, JP-A-9-31396 discloses an example in which an emulsion polymer of a mixture containing a carboxylic acid monomer is prepared in the presence of a reactive emulsifier, and a product whose surface tension is adjusted is used as an ink receiving layer. Have been. JP-A-7-179073 discloses an ink-receiving layer containing a water-dispersible binder and a silane coupling agent. However, in the electrophotographic method, in consideration of the ink fixing property equal to or higher than that of the solvent system and the water resistance of the electrophotographic recording sheet, those disclosed above are not sufficient.

[0005]

SUMMARY OF THE INVENTION According to the present invention, an electrophotographic recording sheet having the same ink fixing property and water resistance as when a conventional solvent-based coating agent is used can be obtained. It is an object of the present invention to provide a water-based coating agent for an electrophotographic recording sheet which does not have a problem.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above problems, and as a result, the following specific emulsions and emulsion compositions are very effective for solving the problems. This has led to the present invention. The first emulsion of the present invention comprises 20 to 70% by weight of an aromatic vinyl monomer and 0.1% of an unsaturated carboxylic acid monomer.
1 to 20% by weight, other polymerizable monomers 79.9 to 10
An emulsion obtained by emulsion polymerization of a monomer mixture containing 10% by weight having a glass transition temperature of 10 ° C to 60 ° C.
It is an emulsion for an electrophotographic recording sheet at a temperature of ° C.

Here, aromatic vinyl monomers used in the production of emulsions include styrene and styrene derivatives, for example, o-methylstyrene, m-methylstyrene, p-methylstyrene, ethylstyrene, vinylxylene, chlorostyrene. , Bromostyrene, vinylbenzyl chloride, p-tert-butylstyrene and the like. The ratio of the aromatic vinyl monomer to the total amount of the monomer mixture is 20 to 70% by weight. When the content is 20% by weight or more, the ink fixing property becomes good, and when the content is 70% by weight or less, the film forming property becomes good. More preferably, the content is 30 to 65% by weight.

[0008] Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid and monoalkyl itaconate. Preferably, acrylic acid and methacrylic acid are used. Unsaturated carboxylic acids function as emulsion stabilization and as crosslinking points when polyvalent metal ions are blended. The ratio of the unsaturated carboxylic acid to the total amount of the monomer mixture is 0.1 to 20% by weight.
It is.

In the production of the emulsion of the present invention, another polymerizable monomer can be added to the monomer mixture. Examples of other polymerizable monomers include α, β-unsaturated monocarboxylic acid esters and the like. α,
Esters of β-unsaturated monocarboxylic acids include, for example, esters of acrylic acid or methacrylic acid. Examples of the esters of acrylic acid or methacrylic acid include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, cyclohexyl acrylate,
-Ethylhexyl acrylate, lauryl acrylate, benzyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl acrylate, butyl methacrylate, isobutyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, benzyl methacrylate, phenyl methacrylate And the like.

[0010] Polymerizable monomers other than those described above may be combined as necessary. For example, hydroxyl group-containing monomers, for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, polyethylene glycol acrylate; amide group-containing monomers, for example, acrylamide, methacrylamide, N, N-methylenebis Acrylamide, diacetone acrylamide, maleic amide, maleimide; a methylol group-containing monomer such as N-methylol acrylamide, N
-Methylol methacrylamide, dimethylol acrylamide, dimethylol methacrylamide; alkoxymethyl group-containing monomers such as N-methoxymethyl acrylamide, N-methoxymethyl methacrylamide, N
-Butoxymethylacrylamide, N-butoxymethylmethacrylamide; epoxy group-containing monomers, for example,
Glycidyl acrylate, glycidyl methacrylate,
Allyl glycidyl ether, methyl glycidyl acrylate, methyl glycidyl methacrylate; polyfunctional monomers such as divinylbenzene, polyoxyethylene diacrylate, polyoxyethylene dimethacrylate, polyoxypropylene diacrylate, polyoxypropylene dimethacrylate, butanediol diacrylate Butanediol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate; mono- or diesters of α, β-ethylenically unsaturated dicarboxylic acids, for example, mono- or dibutyl maleate , Mono or dioctyl fumarate; vinyl esters,
For example, vinyl acetate, vinyl propionate; unsaturated nitriles, for example, acrylonitrile, methacrylonitrile; olefins, for example, butadiene, isoprene; chlorine-containing vinyl monomers, for example, vinyl chloride, vinylidene chloride, chloroprene, and the like.

The other polymerizable monomers may be used alone or as a mixture of two or more. Preferably, α, β-
The use of esters of unsaturated monocarboxylic acids, especially ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate. Other polymerizable monomers,
It is used in the range of 79.9 to 10% by weight based on the total amount of the monomer mixture.

The emulsion of the present invention has a glass transition temperature (Tg) of 10 ° C. to 60 ° C. When contacted with a heat roll at 10 ° C. or higher, the heat resistance blocking property becomes sufficient, and at 60 ° C. or lower, the film forming property becomes good, and cracking after film formation does not occur. Preferably it is in the range of 20C to 55C. The glass transition temperature (Tg) in the present invention is determined by measuring the dried product of the polymer emulsion by a differential scanning calorimeter (DSC).
In this case, it is defined as the inflection point of the change in the calorific value when the temperature is measured using. A specific measuring method will be described later.

The particle size of the emulsion of the present invention is not particularly limited, but is preferably from 20 to 3000 nm.
More preferably, it is 20 to 800 nm. Although there is no particular limitation on the solid content, 10 to 75% by weight is an industrially suitable range, and preferably 20 to 65% by weight. In the present invention, the solid content is defined as a weight ratio after drying the emulsion before drying when the emulsion is dried by a drying method described later.

The emulsion of the present invention is produced by an emulsion polymerization method. As the emulsion polymerization method, a conventionally known method can be employed without any particular limitation. That is, this is a method in which a polymerizable monomer is emulsion-polymerized by using a polymerization initiator in an aqueous dispersion medium, if necessary, in the presence of an emulsifier, a chain transfer agent, seed particles, and other additives. Monomer (mixture)
As a method for introducing the compound into the system, a conventionally known method can be adopted, and a method of initially charging all at once, a method of successively adding, a method of continuously or stepwise controlling the introduction rate and the monomer composition. For example, a method of changing the temperature can be adopted. The monomer (mixture) may be used as it is, or may be used in a state of being dispersed in an aqueous dispersion medium in advance.

As the emulsifier in the emulsion polymerization, anionic, nonionic and cationic surfactants can be used without particular limitation. Examples of the anionic surfactant include, for example, alkali metal salts of alkylbenzene sulfonic acid, alkyldibenzenebissulfonic acid and alkali metal salts thereof, alkali metal salts of alkyl sulfate, alkali metal salts of polyoxyethylene alkylphenol sulfate, and alkali alkyldiphenyl ether disulfonate. Metal salts, alkali metal salts of dialkylsulfosuccinic acids and the like can be used.

As the nonionic surfactant, for example, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyoxyethylene higher fatty acid ester, ethylene oxide-propylene oxide block copolymer and the like can be used. In addition, a reactive surfactant can also be used. The use of a reactive surfactant is effective in the present invention since the water resistance of the obtained polymer does not need to be relatively reduced as compared with the case where a non-reactive surfactant is used. The reactive surfactant has a radically polymerizable functional group in one molecule and a sulfonic acid group, a sulfonic acid ester group, one having one or more functional groups selected from sulfonic acid groups, or in one molecule. Examples include those having a radical polymerizable functional group and having a polyoxyethylene, polyoxypropylene, polyoxyethylene polyoxypropylene composite type alkyl ether or alcohol.

Further, an acrylic water-soluble oligomer may be used in combination with the anionic surfactant. Further, a water-soluble polymer compound having an action as a colloid protective agent such as polyvinyl alcohol, hydroxyethylcellulose, hydroxypropylcellulose and the like can be used if necessary. As the amount of these surfactants and water-soluble polymer compounds increases, the water resistance of the obtained polymer may decrease.Therefore, it is preferable that the amount of use is small, but at least the polymerization stability and It is preferable to use the minimum amount required to maintain the mechanical stability and chemical stability of the product. This amount is usually selected in the range of 0.1 to 7 parts by weight based on 100 parts by weight of the monomer mixture.

The chain transfer agent is not particularly limited, and can be appropriately selected from those commonly used for controlling the molecular weight of a usual polymerization reaction. Such chain transfer agents include, for example, those having 1 to 30 carbon atoms such as propyl mercaptan, butyl mercaptan, and dodecyl mercaptan.
Organic sulfur compounds having 1 to 30 carbon atoms such as mercaptans having an alkyl group of octyl thioglycolate, thioglycolic acid, and diphenyl sulfide; and carbon tetrachloride, carbon tetrabromide, and bromotrichloromethane. Halogenated hydrocarbons having 1 to 20 carbon atoms, and hydrocarbons having an unsaturated group such as α-methylstyrene dimer. These chain transfer agents may be used alone or in combination of two or more. Such a chain transfer agent is used by mixing it with a monomer, using a method of initially charging it all at once, a method of adding it sequentially, a method of continuously or stepwise changing the introduction speed and its composition, and the like. be able to.

As the polymerization initiator, a compound which generates a radical at a temperature of about 0 to 150 ° C. is used.
As the polymerization initiator, a water-soluble one is mainly used, but an oil-soluble one may be used. Representative polymerization initiators include ammonium persulfate, sodium persulfate, water-soluble persulfates such as potassium persulfate, inorganic peroxides such as hydrogen peroxide, benzoyl peroxide, cumene hydroperoxide, lauroyl peroxide, Organic peroxides such as tert-butyl peroxide and tert-butylperoxy-2-ethylhexanoate; and azo compounds such as azobisisobutyronitrile are exemplified. In addition, a so-called redox-based initiator which combines the above-mentioned peroxide and a reducing agent and generates a radical in the presence of a trace amount of metal ion if necessary is also used. Examples of the redox system include a hydrogen peroxide-ferrous chloride system, a cumene hydroperoxide-sodium ascorbate system, and the like. Further, an initiator having an amino group such as azobisisobutylamine can be used.
The amount of the polymerization initiator to be used is usually selected in the range of 0.1 to 2.5 parts by weight based on 100 parts by weight of the total amount of the monomers. Further, the peroxide may be used alone,
Two or more kinds may be used in combination.

The polymerization reaction is carried out usually at a temperature in the range of 0 to 130 ° C., preferably 30 to 100 ° C. The polymerization time is not particularly limited, and is usually 1 to 24 hours, preferably 1 to 24 hours.
10 hours. Further, the polymer emulsion prepared by the above method does not need to be a single layer, and may form a multilayer structure of two or more layers if necessary, or may mix polymer emulsions having different compositions or different particle diameters. You can do it.

The second aspect of the present invention is the above emulsion 10
0.1 parts by weight of polyvalent metal ion in 0 parts by weight (in terms of solid content)
It is an emulsion composition for an electrophotographic recording sheet containing 5 mmol. The polyvalent metal ion used in the second aspect of the present invention is considered to bond with the carboxylic acid on the emulsion surface to form a crosslink. The polyvalent metal ion is not particularly limited as long as it is a polyvalent metal ion that dissociates to some extent in water, and a divalent to pentavalent metal ion can be used. For example, zinc, iron, nickel, copper, titanium, magnesium, calcium, barium, aluminum, zirconium, cadmium, nickel, lead and the like are preferable. Among them, zinc, zirconium and calcium are preferable. These can be used alone or in combination of two or more. These polyvalent metals may be added before, during or after the polymerization, but preferably after the polymerization. These polyvalent metal ions may be used in any form such as an oxide, a hydrate, a salt, and a complex. When the polyvalent metal ion is in the form of a salt, the ion paired with the polyvalent metal ion may be an organic ion, an inorganic ion, or a form containing both. When the ion to be paired with the polyvalent metal ion is an organic ion, the polyvalent metal ion is used in the form of, for example, formate, acetate or oxalate. When the polyvalent metal ion is an inorganic ion, the polyvalent metal ion is used in the form of, for example, chloride, sulfate, nitrate, nitrite, carbonate and the like. When the polyvalent metal ion is in the form of a complex, examples thereof include a combination with the salts listed above.
Specific examples include an ammonium complex, an ammine complex, and a polyvalent carboxylic acid complex. For example, JP-A-62-25
Examples of the aqueous solution include an aqueous solution of zinc carbonate, an aqueous solution of zirconium carbonate, an aqueous solution of zinc acetate, an aqueous solution of zinc acrylate, an aqueous solution of zinc glycine, an aqueous solution of zinc glycine, and an aqueous solution of zinc malate as described in JP-A-0078. Particularly, an aqueous solution of zinc carbonate and an aqueous solution of zirconium carbonate are practically preferable.

When a polyvalent metal ion is added, it is necessary that the ion after the addition be bound to the carboxylic acid while maintaining a dissociated state to some extent without precipitation. In addition, it is necessary that the stability of the emulsion is not impaired. The amount of the polyvalent metal ion used is 0.1 to 15 mmol of the polyvalent metal ion based on 100 parts by weight of the emulsion (in terms of solid content). When the amount is 0.1 mmol or more, the heat blocking property becomes good, and when the amount is 15 mmol or less, there is no problem in the fixing property of the ink.
Preferably it is 2 to 10 mmol.

Various additives may be added to the emulsion or the emulsion composition as required. Specific examples of these include film-forming auxiliaries, fillers, preservatives, bactericides, viscosity adjusters, pH adjusters, defoamers, plasticizers, wetting agents, antistatic agents, crosslinking agents, fluorescent brighteners. And so on. Among these, the filler is not particularly limited, but one or more kinds are appropriately selected from those generally used in paper coating for the purpose of improving ink fixing property and coating film strength of a compound. Can be used. For example, silica, calcium carbonate, clay, calcined clay, kaolin clay, titanium oxide, organic pigment (plastic pigment), zeolite, diatomaceous earth, talc, aluminum oxide, aluminum hydroxide, white carbon, magnesium silicate, magnesium aluminosilicate, carbonic acid magnesium,
Barium sulfate and the like.

The emulsion or emulsion composition for an electrophotographic recording sheet prepared by blending the above can be used surprisingly regardless of the material of the electrophotographic recording sheet. Various colored or white papers such as synthetic paper, art paper, coated paper, cast coated paper, wallpaper, backing paper, synthetic resin impregnated paper, emulsion resin impregnated paper, synthetic rubber latex impregnated paper, synthetic resin internal paper, and paperboard And a substrate for labels, and a film material prepared by using polyethylene terephthalate resin, acrylic resin, polyethylene resin, diacetate resin, triacetate resin, polyimide resin, etc. alone or in combination of several kinds. In particular, when used for an OHP film, a transparent resin film or the like is appropriately selected, the emulsion for an electrophotographic recording sheet is coated, and an image can be printed by an electrophotographic method. For applications that do not require transparency, electronic printing can be performed by appropriately coating a resin film, paper, or the like according to the purpose.

The coating of the emulsion or emulsion composition may be applied on one or both sides of the substrate as required. If necessary, the emulsion may be coated a plurality of times to form a multilayer. As the coating method, a known coating method can be appropriately used. For example, roll coater, blade coater, air knife coater, gate roll coater, bar coater,
Coating methods using a size press, a spray coat, a gravure coater, a curtain coater, and the like can be given.

As for the drying method following the coating, known methods can be used as appropriate. For example, hot air drying, hot drum drying, etc. In addition, to the extent that the ink fixing property is not impaired, one or both of the base sheets coated with the emulsion for the electrophotographic recording sheet may be subjected to a corona discharge treatment or a plasma discharge treatment to further secure the ink fixability, or Additional processing such as providing an anti-curl layer on the side opposite to the emulsion coat surface, or providing a coat layer on the surface after forming an image by electrophotography to further improve long-term storage properties There is no problem with applying.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to examples. In the text, parts are parts by weight and%
Indicates weight%, respectively. Various physical properties were measured and evaluated by the following methods. (A) Glass transition temperature (Tg) After drying the emulsion at 105 ° C. for 3 hours, an appropriate amount of the dried product is measured using a differential scanning calorimeter (DSC). The measurement was performed at a heating rate of 10 ° C./min, and the inflection point of the change in calorific value was defined as Tg. (B) Solid component 0.5-1.0 g of the emulsion is precisely weighed in an aluminum dish,
It is left to dry at 105 ° C. for 3 hours. The weight percentage of the heating residue after drying with respect to the weight before drying was taken as the solid content. (C) Particle size The emulsion is measured with a particle measuring device (LEED & NORT).
Product name: MICROTRACUPA15, manufactured by HRUP
0). The volume average value of the measured values was used as the particle size. (D) Ink fixability A 100 μm thick P was prepared by adjusting the solid content to 20%.
Apply to ET film with # 8 bar coater, 100 ℃
2 minutes in a hot air dryer. Dried PE
Using T-film, LP-8 manufactured by Seiko Epson Corporation
Printing is performed by electrophotography using 000C, and the printed surface is visually evaluated. The printing pattern was solid printing of each color of cyan, magenta, yellow, and black. The same printing was performed on a commercially available OHP sheet coated with a solvent-based coating agent, and used as a comparative control of the present invention. ○ Pass above.

○: There is no unevenness or blur on the printed surface. The color development of the printed surface is equivalent to a commercially available solvent-based sheet. Δ: There is no unevenness or blurring on the printed surface, but the coloring on the printed surface is slightly inferior to that of a commercially available solvent-based sheet. ×: Some unevenness or blurring is observed on the printed surface, or the printed surface is considerably inferior in color to a commercially available solvent-based sheet. (E) Film forming properties A blended product whose solid content has been adjusted to 20% is made of P having a thickness of 100 μm.
Apply to ET film with # 8 bar coater, 100 ℃
2 minutes in a hot air dryer. The coating film after drying is visually evaluated. ○ Pass above.

○: A state in which the entirety is transparent and there is no crack at the end of the coating surface △: A state in which the end of the coating surface is cracked or a part of the coating surface is whitened ×: The whole coating surface is whitened And cracks on the edges. (F) Heat blocking properties The blended product whose solid content was adjusted to 20% was prepared using a 100 μm thick P
Apply to ET film with # 8 bar coater, 100 ℃
2 minutes in a hot air dryer. A 1 cm-wide stainless steel square bar (weight: 300 g) adjusted to 120 ° C. is placed on the dried coating film for 1 second, and then lifted. The condition after lifting is visually evaluated. ○ Pass above.

A: The PET film does not lift even when the square bar is lifted. Nothing remains on the application surface. ○… When the square bar is lifted, PET film is 5c
Lift less than m. Nothing remains on the application surface. △… When the square bar is lifted, PET film is 5c
Lift more than m.

When the square bar is peeled off from the film, a trace of the square bar left on a part of the coating film remains. ×… After lifting the square bar, PET film is 5cm
Lift up. When the square bar is peeled off from the film,
Traces remain over / 4. (G) Water resistance A 100 μm-thick P
Apply to ET film with # 8 bar coater, 100 ℃
2 minutes in a hot air dryer. Dried PE
Using T-film, LP-8 manufactured by Seiko Epson Corporation
Printing is performed by electrophotography using 000C. The printing pattern was solid printing of each color of cyan, magenta, yellow, and black. A few drops of water are dropped on the printing surface, and after 15 seconds, wiped off with paper. The state after the wiping is visually observed. ○ Pass above.

○: No ink drop off from the printing surface. Δ: Ink is seen to be slightly dropped from the printing surface. ×: Significant ink dropout from the printing surface.

[0033]

Example 1 548.5 parts of water, α-
Sulfo-ω (1-((nonylphenoxy) methyl-2-
(2-propenyloxy) ethoxy-poly (oxy-
1,2-ethanediyl) ammonium salt (Adekaria Soap SE-10, manufactured by Asahi Denka Kogyo KK)
2.0 parts of an aqueous solution. Next, 245 parts of methyl methacrylate, 460 parts of styrene, 275 parts of 2-ethylhexyl acrylate, 20 parts of methacrylic acid, and a 3.8% 26% aqueous solution of sodium polyoxyethylene alkylphenyl ether sulfate (trade name: Revenol WZ, manufactured by Kao Corporation). Parts, 12.0 parts of a 25% aqueous solution of polyoxyethylene nonylphenyl ether (trade name: Emulgen 920, manufactured by Kao Corporation), and 3.5 parts of dodecylbenzenesulfonic acid
Part, 25% of α-sulfo-ω (1-((nonylphenoxy) methyl-2- (2-propenyloxy) ethoxy-poly (oxy-1,2-ethanediyl) ammonium salt)
An aqueous solution (16.0 parts (in terms of solid content)), ammonium persulfate (2.0 parts) and water (376.2 parts) are uniformly mixed using an emulsifier and emulsified to prepare an emulsion. While maintaining the reaction vessel at 80 ° C., the emulsion was gradually dropped therein for 180 minutes to cause a reaction. After the completion of dropping, the solution is kept at the same temperature for 4 hours.
After stirring for an hour, the reaction was terminated. Thereafter, the reaction vessel was cooled, and the pH was adjusted to 8 by dropping ammonia water little by little to obtain an emulsion. The solid content was 51%, and the glass transition temperature was 45 ° C. The particle size was 190 nm.

While stirring the obtained emulsion, a blended product is prepared according to the following formulation. Emulsion 100 parts (with water) 125 parts of water 30 parts of butyl carbitol (film forming aid) 255 parts in total (solid content 20%) Various physical properties were evaluated using this compounded product. . Table 1 shows the results.

[0035]

Examples 2 to 6 An emulsion was prepared by carrying out polymerization in the same manner as in Example 1 except that the amounts of styrene, methyl methacrylate and 2-ethylhexyl acrylate in the emulsion were changed as shown in Table 1. In the same manner as in Example 1, a blended product having a solid content of 20% was produced. Various physical properties were evaluated using these, and the results are shown in Table 1.

[0036]

Comparative Examples 1 to 4 Polymerization was carried out in the same manner as in Example 1 except that the amounts of styrene, methyl methacrylate and 2-ethylhexyl acrylate in the polymer emulsion were changed as shown in Table 1, to obtain an emulsion. Using this emulsion, a blend was prepared in the same manner as in Example 1 to obtain PE.
It was applied to a T film and dried. Table 1 shows the results of the evaluation of various physical properties.

[0037]

EXAMPLE 7 While stirring 53 parts of water, 17 parts of a 25% aqueous ammonia solution was added dropwise, and 12 parts of zinc oxide were further added dropwise and stirred until the liquid became transparent to prepare zinc water. While sufficiently stirring 100 parts of the emulsion prepared in Example 1 (containing water), the zinc water 0.28
The mixture was added dropwise and the mixture was further stirred for 10 minutes. To the emulsion composition thus obtained, water and butyl carbitol were added in the same amount as in Example 1 to obtain a compound having a solid content of 20%. By way of P
It was applied to an ET film, dried, and evaluated. Table 2 shows the results.

[0038]

Examples 8 to 9 An emulsion composition was prepared in the same manner as in Example 7 except that the amount of zinc water was changed as shown in Table 2. The prepared emulsion composition was made into a blended product having a solid content of 20% in the same manner as in Example 7 except that the blending amount was as shown in Table 2, and then applied to a PET film.
Dried and evaluated. Table 2 shows the results.

[0039]

Comparative Examples 5 to 7 The emulsions prepared in Example 1, Comparative Example 1 and Comparative Example 4 were used, and the other components were as shown in Table 2.
Each emulsion composition and compounded product were produced in the same manner as in Example 7, except that the composition described in Example 1 was used. Then, PET
It was applied to a film, dried and evaluated. Table 2 shows the results.

[0040]

[Table 1]

[0041]

[Table 2]

[0042]

The sheet prepared by applying and drying the emulsion or the emulsion composition of the present invention has excellent heat blocking properties and water resistance, and has good ink fixing properties when used in electrophotographic printing. Further, better performance can be obtained by using a polyvalent metal ion in combination with the emulsion or the like.

Claims (2)

[Claims] 1 to 20% by weight of an aromatic vinyl monomer,
An emulsion obtained by emulsion polymerization of a monomer mixture containing 0.1 to 20% by weight of an unsaturated carboxylic acid monomer and 79.9 to 10% by weight of another polymerizable monomer, the glass transition of which is obtained. An emulsion for an electrophotographic recording sheet having a temperature of 10 ° C to 60 ° C. 2. An emulsion composition for an electrophotographic recording sheet, wherein 0.1 to 15 mmol of a polyvalent metal ion is mixed with 100 parts by weight of the emulsion according to claim 1 (in terms of solid content).