JP2000230144A - Emulsion of cellulose nitric esters - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both an emulsion of carboxyalkyl cellulose nitric esters useful for coating materials, inks, or the like, and good in preservation stability without containing an organic solvent and a water-based compounded composition, or the like, containing the emulsion. SOLUTION: This emulsion comprises 100 pts.wt. of carboxyalkyl cellulose nitric esters having 0.2-2.95 degree of substitution of nitric ester groups per anhydroglucose unit and 0.05-2.80 degree of substitution of carboxyalkyl ether groups, 0.02-30 pts.wt. of polyvinyl alcohol and 70-1,000 pts.wt. of water and has 0.01-5 μm average particle diameter. The water-based compounded composition contains the emulsion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic solvent-free emulsion of carboxyalkyl cellulose nitrate useful for paints, inks and the like, and to an aqueous composition containing the same.

[0002]

2. Description of the Related Art Cellulose nitrates have excellent blocking resistance, drying properties, heat resistance, pigment dispersibility and gloss, so that they can be used in paints, printing inks, paper coatings, plastic films and sheet coatings, textile processing, magnetic processing, and the like. It is frequently used as a component of compounding compositions such as paints, conductive pastes, and cosmetic nail polish. However, in most of these uses, since cellulose nitrates are insoluble in water, they need to be dissolved in an organic solvent, and there are problems such as a working environment due to the organic solvent volatilizing in a film forming process.

[0003] For this reason, attempts to use cellulose nitrates in an aqueous dispersion have been conventionally proposed. As one of the aqueous coating compositions, an aqueous dispersion in which cellulose nitrates are dissolved in an organic solvent together with a plasticizer and / or a resin that dissolves the same in an organic solvent and dispersed in water in the presence of an emulsifier is used for leather or the like. Also known as However, this composition, which contains a large amount of an organic solvent, is essentially the same as an organic solvent-based composition and is insufficient for improving the working environment.

Further, Japanese Patent Application Laid-Open Nos. 58-80358 and 58
An aqueous dispersion obtained by dissolving cellulose nitrates disclosed in JP-A-69214 and JP-A-60-195172 in an acrylic monomer or oligomer, dispersing in water using an emulsifier, and then subjecting to radical polymerization. Proposed. However, even in these methods, a large amount of an organic solvent is required for forming a film, and thus the above-mentioned problems have not been solved.

On the other hand, Japanese Patent Application Laid-Open No. 59-71342 has attempted to improve the water dispersibility by oxidizing cellulose nitrates to introduce a carboxyl group which is a hydrophilic group. Has a small carboxy group content of several milliequivalents, so that water and an organic solvent must be used in combination, which is insufficient for improving the working environment. JP-A-10-306249 discloses that a carboxyalkylcellulose nitrate can be prepared by using a generally well-known anionic and / or nonionic emulsifier to obtain an emulsion having substantially no organic solvent and having good storage stability. Is described. Although this was intended to improve the above-mentioned problem, the market has demanded further improvement in storage stability.

[0006]

The object of the present invention is to provide an emulsion of carboxyalkylcellulose nitrates containing no organic solvent and having further improved storage stability, and an aqueous composition containing the emulsion. It is the purpose.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that a polyvinyl alcohol emulsifier is useful, and have completed the present invention. That is, 100 parts by weight of a carboxyalkylcellulose nitrate having a degree of substitution of a nitrate ester group of 0.2 to 2.95 and a degree of substitution of a carboxyalkyl ether group of 0.05 to 2.80 per anhydroglucose unit, Alcohol 0.02 to 30 parts by weight, water 70 to 1
The present invention relates to an emulsion having an average particle size of 0.01 to 5 μm comprising 000 parts by weight, an aqueous composition containing the emulsion, and an aqueous ink jet printer receiver.

The carboxyalkylcellulose nitrates used in the present invention are those having a nitric ester group substitution degree of 0.2 to 2.
95, the degree of carboxyalkyl ether substitution is 0.05
To 2.80, specifically, an aqueous cellulose derivative disclosed in JP-A-5-39301 and JP-A-5-39302. If the nitrate ester group substitution degree is less than 0.2, the water resistance of the film is insufficient, and if it exceeds 2.95, the water dispersibility deteriorates. If the degree of substitution of the carboxyalkyl ether group is less than 0.05, the hydrophilicity is insufficient and the emulsion stability is poor. If it exceeds 2.80, the viscosity is significantly increased due to the excessive hydrophilicity, and the water resistance of the film becomes insufficient. .

The polyvinyl alcohol used in the present invention is a known one, and any of anionic, nonionic and cationic can be used alone and / or in combination. Examples of anionics include carboxylic acid-modified types,
Examples of the sulfonic acid-modified type and the nonionic type include non-modified, completely and partially saponified types having a saponification degree of 60 mol% or more, terminal SH group-modified type, terminal paraffin-modified type, acetoacetyl group-modified type, and cationic examples. Is a single or a combination of two or more of tertiary and quaternary anmonium-modified types. Since polyvinyl alcohol can be used alone, an emulsion using nonionic and / or cationic type polyvinyl alcohol has good compatibility with anionic aqueous ink and is suitable as a raw material for coating materials for aqueous inkjet printer receivers. From this point, the cationic type is particularly preferable.

If the amount is less than 0.02 parts by weight per 100 parts by weight of the carboxyalkylcellulose nitrates, the emulsion stability is insufficient. Is not preferred because the water resistance is worse. A preferred range is 0.5 parts by weight or more and 15 parts by weight or less. The amount of water of the present invention is 70
Parts or more is necessary, and if it is less than that, the solid content of the emulsion becomes too high, so that the viscosity is remarkably increased and it becomes difficult to use.
If the amount exceeds 1,000 parts by weight, the solid content decreases, so that it is not economical.

The average particle size of the emulsion of the present invention is 0.1.
If it is from 0.01 μm to 5 μm, and if it is less than 0.01 μm, the emulsion viscosity becomes too high and it is difficult to use.
If it exceeds m, the storage stability of the emulsion is poor, and a precipitate is formed during storage. A preferred range is 0.05 μm or more and 1 μm or less. Some or all of the carboxyl groups of the carboxyalkyl cellulose nitrates of the present invention may be used alone or in combination with an alkali metal ion, an alkaline earth metal ion, an ammonium ion, an organic amine or the like.
It may be neutralized with more than one kind of cation.

The emulsion of the present invention can be produced by a known method for producing a resin emulsion by post-emulsification. As an example, a mixture of carboxyalkylcellulose nitrates, polyvinyl alcohol and water is mixed with a high-speed rotating homogenizer or the like. After pre-emulsification, emulsification with a pressure homogenizer, or dissolution in an organic solvent dissolving carboxyalkylcellulose nitrates or a mixed solvent of organic solvent and water, and adding an emulsifier, pressure homogenizer or stirring After emulsification with a homogenizer or the like, a method of removing an organic solvent in the emulsion by distillation or the like may be used. When an organic solvent is used, it is necessary to remove the organic solvent in the emulsion by distillation or the like, but the average particle size can be made smaller than when no organic solvent is used. When the amount of the organic solvent is larger than the amount of water, the organic solvent undergoes a phase transition from the W / O type to the O / W type in the process of being distilled off, and the dispersion of the particle size distribution of the obtained emulsion is Become smaller.

The organic solvent used in the production described above has a boiling point of less than 100 ° C., and examples thereof include methanol, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, and ethyl acetate.
The emulsion of the present invention can be blended with other water-dispersible and / or water-soluble resins to form an aqueous blended composition.

Examples of the water-dispersible resin include emulsion latex described in Table 2-3 (published by Taisei Co., Ltd., page 24 of "Emulsion Latex Handbook"), for example, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer. Copolymer, methyl methacrylate / butadiene copolymer, polychloroprene, vinylpyridine copolymer, polyisoprene, butyl rubber, polysulfide rubber, polyurethane, polybutene, polyacrylate, vinyl chloride copolymer, vinyl acetate copolymer Polymers, vinylidene chloride copolymers, polyethylene, vinyl acetate / ethylene copolymers, or styrene / acryl emulsions, epoxy resin emulsions, fluororesin emulsions, polyester emulsions, or colloids containing these resins as main components One or more combinations of Isupajon thereof.

Examples of the water-soluble resin include maleic acid-styrene copolymer, maleic acid-acrylic acid and methacrylic ester copolymer, acrylic acid-styrene copolymer, acrylic acid-acrylic acid and methacrylic ester copolymer, polyurethane resin ,
Examples thereof include polyamide resins, shellac, casein, polyvinyl alcohol, and cellulose ethers such as hydroxyethyl and hydroxypropylcellulose and carboxymethylcellulose, alone or in combination of two or more.

In the present invention, known anionic, nonionic, cationic and amphoteric surfactants may be added if necessary. Examples of the anionic include fatty acid metal soap, N-acyl amino acid salt, polyoxyethylene alkyl ether carboxylate, acylated peptide, alkyl sulfonate, alkylbenzene and alkylnaphthalene sulfonate, phthalene sulfonate-formalin Polycondensate, sulfosuccinate, α-olefin sulfonate, N-acyl sulfonate, sulfated oil, alkyl sulfate, alkyl ether sulfate, polyoxyethylene alkyl allyl ether sulfate, alkylamide sulfate, alkyl Examples of nonionics such as phosphates, polyoxyethylene alkyl ether phosphates, polyoxyethylene alkyl allyl phosphates, polycarboxylates include polyoxyethylene alkyl and alkyl phenyl ethers, alkyl allyl formaldehyde Compound polyoxyethylene ether, polyoxyethylene polyoxypropylene block copolymer, polyoxyethylene polyoxypropyl alkyl ether, glycerin ester polyoxyethylene ether, sorbitan ester polyoxyethylene ether, sorbitol ester polyoxyethylene ether, polyethylene glycol Fatty acid esters, glycerin esters, polyglycerin esters, sorbitan esters, propylene glycol esters, sucrose esters, fatty acid alkanolamides, polyoxyethylene fatty acid amides, polyoxyethylene alkylamines, amine oxides, etc. Amine salts, aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts Examples of amphoteric compounds such as carboxybetaine, aminocarboxylate, imidazolinium betaine, lecithin, and alkylamine oxide can be used alone or in combination of two or more.

The aqueous composition containing the emulsion of the present invention may contain a known pigment and / or dye in a dispersoid or a dispersion medium depending on the purpose of use. Examples of pigments include iron oxide, lead white, lead red, graphite, silver vermilion, ultramarine, navy blue, cobalt oxide, titanium oxide, strontium chromate, titanium yellow, titanium black, zinc chromate, iron black, molybdenum red, and molybdenum white. , Litharge, lithopone, carbon black, insoluble azo, condensed azo, soluble azo, dye lake, phthalocyanine blue, phthalocyanine green, watchan red, isoindolinone, quinacridone, dioxazine violet, perinone, perylene, barium sulfate, calcium carbonate, Clay, magnetic iron oxide, barium titanate,
It can be used alone or in combination of two or more of gold, silver and the like. Examples of the dye include known azo, bisazo, trisazo, azo metal complex salts, anthraquinone, triphenylmethane, polymethine, indigoid, stilbene, methylene blue, malachite green, rhodamine, alizarin and the like. Alternatively, they can be used in combination of two or more.

The carboxyalkylcellulose nitrates used in the present invention may contain known plasticizers conventionally used. Examples include phosphate esters, phthalates, aliphatic monobasic esters, aliphatic dibasic esters, dihydric alcohol esters, oxyacid esters, etc., used alone or in combination of two or more. it can.

Further, the aqueous composition containing the emulsion of the present invention may further contain a known antifoaming agent, antifreezing agent, antistatic agent, antifogging agent in a dispersoid or a dispersion medium according to the purpose of use. , Rust inhibitor, fungicide, heat stabilizer, light stabilizer,
An antioxidant and the like may be added. Their use further extends the utility of the present invention. The above water-dispersible and / or water-soluble resins, surfactants, pigments, dyes, plasticizers, defoamers, antifreezing agents, antistatic agents, antifogging agents, rust inhibitors, fungicides, heat The stabilizer, light stabilizer, antioxidant and the like may be blended before, during, or after the production of the emulsion of the present invention, or during the production of the aqueous composition.

The emulsion of carboxyalkylcellulose nitrates used in the present invention is excellent in water resistance, blocking resistance, drying property, heat resistance, gloss and the like. The effect and the resulting coating film are excellent in hardness, aqueous / oil-based ink fixing property, releasability, etc. in addition to the above-mentioned properties. Accordingly, the emulsion of the present invention or an aqueous composition containing the same may be used as a raw material for paints, inks, adhesives, release agents, plastic resins, etc., as paper, plastic sheet / film, metal, leather, cloth, etc. It can be widely used as a raw material for coating materials and as a raw material for papermaking, textile processing agents, magnetic paints, conductive pastes, decorative nail polish, and the like. An emulsion using a nonionic and / or cationic type polyvinyl alcohol is suitable as a raw material for a coating material of an aqueous ink jet printer receiver because it has good compatibility with an anionic aqueous ink.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments will be described in detail.
The average particle size of the emulsion was LA-9 manufactured by HORIBA.
Measured with a 20 particle size distribution analyzer. The viscosity is T at 25 ° C.
It was measured with a BM type viscometer manufactured by OKIMEC.

The pH is PH81p manufactured by YOKOGAWA.
It was measured with an H meter. The concentration of methylethylkenne in the emulsion was measured by gas chromatography. The evaluation of the ink fixing ability is performed by solid printing on a recording sheet in an HQ mode (high quality, 360 × 360 dpi) and a FINE mode (high image quality, 720 × 360 dpi) using an inkjet printer BJC-420J manufactured by Canon Inc. Then, the printed part was immersed in water at room temperature for 2 minutes.
And

[0023]

Example 1 In a beaker, 286 g of carboxymethylcellulose nitrate water-wet cotton (30% by weight of water) having an average particle diameter of 49 μm and a carboxymethyl ether nitrate substitution degree of 1.87 and a carboxymethyl ether substitution degree of 0.7 were added. 2.7 g of methyl ethyl ketone and 300 g of methyl ethyl ketone were stirred at a rotation speed of a stirrer of 1000 rpm, the temperature was increased to 70 ° C., and anionic polyvinyl alcohol (KL-504, carboxylic acid-modified type, manufactured by Kuraray Co., Ltd.
A solution in which 20 g of a saponification degree of 73.5 to 76.5 mol% was dissolved was added thereto, and the mixture was held for 1 hour to obtain an emulsion. Next, the emulsion was transferred to a rotary evaporator and treated under reduced pressure at 70 ° C. until the concentration of methyl ethyl ketone in the solution became less than 1%. The resulting emulsion is milky white, has a solid content of 22%, a viscosity of 3200 cps,
The average particle size was 0.18 μm, and there was no sediment for 2 months or more at room temperature, and the mixture was stable.

[0024]

Example 2 Nonionic polyvinyl alcohol manufactured by Kuraray Co., Ltd. (M-205, terminal SH group-modified type, saponification degree 87.
Except that 0 to 89.0 mol%) was used, the treatment was carried out in the same manner as in Example 1. The obtained emulsion was milky white, had a solid content of 22%, a viscosity of 33000 cps, a pH of 4.4, an average particle size of 0.19 μm, and was stable without any sediment at room temperature for more than 2 months.

[0025]

Example 3 Example 1 was repeated except that cationic polyvinyl alcohol (C-506, quaternary ammonium modified type, saponification degree 74.0 to 80.0 mol%) manufactured by Kuraray Co., Ltd. was used.
An emulsion was obtained in the same manner as described above. The obtained emulsion was a milky white emulsion having a solid content of 22%, a viscosity of 3000 cps, a pH of 4.4 and an average particle size of 0.16 μm, and was stable at room temperature with no sediment for 2 months or more.

[0026]

Example 4 The emulsions obtained in Examples 2 and 3 were
On a 0 μm polyester sheet, the film thickness after drying is 10
Coating was performed with a bar coater so as to have a thickness of 20 μm, and the coating was dried in a hot air oven at 100 ° C. for 5 minutes to obtain an inkjet receiver. The ink fixing ability is HQ mode = ○, F
INE mode = ○.

[0027]

EFFECT OF THE INVENTION By using polyvinyl alcohol as an emulsifier, an emulsion of carboxyalkylcellulose nitrates containing no organic solvent and having excellent storage stability can be obtained, and an aqueous composition containing the same can be provided. It has become possible. The excellent properties of carboxyalkyl cellulose nitrates such as water resistance, blocking resistance, drying property, heat resistance, gloss, etc., paints, inks,
As raw materials for adhesives, release agents, plastic resins, etc., paper, plastic sheets / films, metals, leather,
As a raw material for coating materials such as cloth and aqueous inkjet printer receivers, papermaking, textile processing agents, magnetic paints,
It can be widely applied as a raw material for conductive paste, cosmetic nail polish, etc.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D21H 19/34 B01J 13/00 B 4L055 // B01J 13/00 C09D 101/18 C09D 101/18 B41J 3 / 04 101Y F-term (reference) 2C056 FC01 2H086 BA53 BA60 4G065 AA01 AA06 AA09 AB01Y AB02Y AB03Y AB06Y AB09Y AB11Y AB17Y AB21Y AB38Y BA07 BB06 CA02 DA05 DA06 DA07 DA09 DA10 EA01 EA03 EA10 MA044 EA37 EA38 EA44 EA45 EA48 4L055 AG46 AG64 AG97 AH33 AJ02 EA16 EA29 EA32 FA12 FA19 FA30 GA09

Claims (3)

[Claims] 1. A carboxyalkyl cellulose nitrate having a degree of substitution of 0.2 to 2.95 and a degree of substitution of carboxyalkyl ether group of 0.05 to 2.80 per one unit of anhydroglucose unit. Department,
0.02 to 30 parts by weight of polyvinyl alcohol, water 70 to
Emulsion consisting of 1000 parts by weight and having an average particle size of 0.01 to 5 μm 2. An aqueous composition comprising the emulsion according to claim 1. 3. A receiver for an aqueous inkjet printer, comprising the emulsion according to claim 1.