JPH07278480A - Fine polymer particle for ink-jet recording ink - Google Patents

Abstract

PURPOSE:To improve drying properties, non-blurring properties, clearness, durability, and stability to ejection from a nozzle by condensing an organosilane compound in the presence of polymer particles. CONSTITUTION:At least 10wt.% polymerizable monomer is emulsion- or suspension-polymerized with up to 10wt.% crosslinking monomer to obtain polymer particles. In the presence of 100 pts.wt. these particles, 0.1-900 pts.wt. organosilane compound is condensed in a solvent having a solubility in water of 10<-3>wt.% or lower, at 90-30 deg.C and a pH of 4-10. Thus, these particles are obtained which contain a polysiloxane and have a particle diameter of 0.01-0.2mum.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention is excellent in drying property when ink is ejected as droplets ejected from an ejection orifice of a recording head to cause bleeding, sharpness of contour, sharpness and durability. The present invention relates to polymer particles capable of producing an inkjet recording ink having excellent printing quality such as, and excellent nozzle discharge stability and water resistance of printed matter.

[0002]

2. Description of the Related Art Conventionally, those that have a high drying speed after printing are
There is a problem that nozzle ejection stability is deteriorated due to clogging that accompanies drying and solidification of ink, and conversely, those having good ejection stability have poor drying properties. To achieve both of these, JP-A-55-1
No. 6042, JP-A-55-29546, etc.
It has been proposed to use a dye, a specific high-boiling point water-soluble solvent (wetting agent) and water as main components in order to improve nozzle ejection stability, and various surfactants for improving quick drying property.
However, the ink penetrates too much into the paper, causing bleeding,
There were new problems such as sharpness of contour, sharpness, and durability, which deteriorated the printing quality, which was not satisfactory. On the other hand, in JP-A-3-79678, 50-30
A method of adding a 0 angstrom ultrafine particle emulsion is disclosed. Also, JP-A-54-5850
4, JP-A-60-38481, JP-A-55-139.
No. 471, JP-A-3-250069, a hydrophobic dye,
An ink jet recording ink comprising a polymer emulsion colored with a basic dye and a disperse dye is disclosed. However, in these methods, although the blurring and the sharpness of the contour are good, there is a problem that the nozzle is hard to be clogged because the film forming property of the fine particles is too good, the nozzle ejection stability is deteriorated, and the printing is blurred.

[0003]

SUMMARY OF THE INVENTION The present invention has been made against the background of the above-mentioned conventional technical problems, and is excellent in drying property and excellent in print quality such as bleeding, sharpness of contour, sharpness and durability. Another object of the present invention is to provide polymer fine particles for inkjet recording ink, which can provide inkjet recording ink excellent in nozzle ejection stability and water resistance of printed matter.

[0004]

DISCLOSURE OF THE INVENTION The present invention contains polymer fine particles for an ink jet recording ink, particularly polymer particles, which contain polysiloxane and have an average particle diameter of 0.01 to 0.2 μm. The present invention provides polymer fine particles for ink jet recording ink, which are obtained by condensation reaction of 0.1 to 900 parts by weight of an organosilane compound in the presence of 100 parts by weight. Hereinafter, the present invention will be described in detail.

The polymer fine particles for ink jet recording ink of the present invention are polymer particles obtained by polymerizing a polymerizable monomer by emulsion polymerization, suspension polymerization or dispersion polymerization, preferably emulsion polymerization. It is obtained by adding polysiloxane to the polymer particles (hereinafter referred to as “polymer particles (A)”).
Application of polysiloxane here means polymer particles (A)
The polysiloxane is partially or entirely laminated on the surface of the polymer and / or the polysiloxane is present inside the polymer particles (A). The proportion of polysiloxane is usually 100 parts by weight of the polymer particles (A).
The amount is 0.1 to 900 parts by weight, preferably 10 to 300 parts by weight, particularly preferably 1 to 150 parts by weight, and most preferably 2 to 100 parts by weight. The amount of polysiloxane is 0.1
If it is less than 100 parts by weight, the slidability will be poor, and if it exceeds 900 parts by weight, the heat resistance will be poor.

In the present invention, as the polymerizable monomer used for producing the polymer particles (A), aromatic monovinyl compounds such as styrene, ethylvinylbenzene, α-methylstyrene, fluorostyrene and vinylpyrine, Vinyl cyanide compounds such as acrylonitrile and methacrylonitrile, ethyl acrylate, butyl acrylate, 2-ethylhexylethyl acrylate, β
-Acrylate ester monomers such as methacryloyloxyethyl hydrogen phthalate, 2-acroyloxyethyl-2-hydroxyethyl phthalic acid, 2-hydroxy-3-phenoxypropyl acrylate, glycidyl acrylate, N, N'-dimethylaminoethyl acrylate , Butyl methacrylate, 2-ethylhexyl methacrylate, methyl methacrylate, methoxydiethylene glycol methacrylate, methoxy polyethylene glycol methacrylate, 2-methacryloyloxyethyl-2-hydroxypropyl phthalate, ethyl methacrylate, butyl methacrylate, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate , N, N'-dimethylaminoethylmeth Methacrylic acid ester monomers, silicone-modified monomers such as acrylates, macromonomers,
Alternatively, monomers such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid, or acid anhydrides of dicarboxylic acids and dicarboxylic acids, and amide monomers such as acrylamide and methacrylamide can be used. In addition, conjugated double bond compounds such as butadiene and isoprene, vinyl ester compounds such as vinyl acetate, 4-methyl-1-pentene, and other α-orifine compounds can be mentioned. Preferred polymerizable monomers are aromatic vinyl compounds, (meth)
Examples include acrylic acid esters and monocarboxylic acids.

The polymerizable monomer used in the polymer particles (A) may contain a crosslinkable monomer. When a crosslinkable monomer is used, it is used in a proportion of 10% by weight or more, preferably 15% by weight or more, and more preferably 20% by weight or more of the polymerizable monomer. Examples of the crosslinkable monomer used in the polymer particles (A) include non-conjugated divinyl compounds such as divinylbenzene, and the following compounds as polyvalent acrylate compounds. These are used alone or in combination of two or more. Specific examples of the polyvalent acrylate compound include polyethylene glycol diacrylate, 1,3-butylene glycol diacrylate,
1,6-butylene glycol diacrylate, 1,6-
Hexanelen glycol diacrylate, neopentyl glycol diacrylate, polypropylene diacrylate, 2,2'-bis (4-acryloxyproproxyphenyl) propane, 2,2'-bis (4-acryloxydiethoxyphenyl) propane, Diacrylate compounds such as methylenebisacrylamide, trimethylolpropane triacrylate, trimethylolethane triacrylate, triacrylate compounds such as tetramethylolmethane triacrylate, ditrimethylolpropane tetraacrylate, tetramethylolmethane tetraacrylate, pentaerythritol tetraacrylate, etc. Tetraacrylate compound, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, tri Chi glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3
-Butylene glycol dimethacrylate, 1,4-butylene glycol dimethacrylate, 1,6-hexane glycol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate,
Examples thereof include methacrylate compounds such as 2,2-bis (4-methacryloxydiethoxyphenyl) propane and trimethacrylate compounds such as trimethylolpropane trimethacrylate and trimethylolethanetrimethacrylate. Of the above, divinylbenzene, ethylene glycol dimethacrylate, or trimethylolpropane trimethacrylate are preferable, and divinylbenzene is particularly preferable.

In the present invention, polysiloxane is usually condensed with an alkoxysilane compound represented by the general formula RnSi (OR ') _4-n or a cyclic siloxane represented by RmSiO [ _{(4-m) / 2} ]. I will do it. In the general formula, n is an integer of 0 to 3, m is a number of 0 to 3, and R is preferably an organic group having 1 to 8 carbon atoms, such as a methyl group,
Alkyl group such as ethyl group, n-propyl group, i-propyl group, other γ-chloropropyl group, vinyl group,
3,3,3-Trifluoropropyl group, γ-glycidoxypropyl group, γ-methacryloxypropyl group, γ-mercaptopropyl group, phenyl group, 3,4-epoxycyclohexylethyl group, γ-aminopropyl group, etc. Is mentioned. In the formula, R'preferably has 1 to 5 carbon atoms.
Is an alkyl group or an acyl group having 1 to 4 carbon atoms,
Examples thereof include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a sec-butyl group, a tert-butyl group and an acetyl group. In the formula, when the carbon number of R exceeds 9 or the carbon number of R'exceeds 6, the polysiloxane is not sufficiently added to the polymer particles (A), and thus the obtained polymer fine particles adhere to the film. The sex is not enough.

Examples of the above-mentioned organosilane compound include the following. Specific examples of these alkoxysilane compounds include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, and n-propyl. Trimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane,
γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxy Silane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ- Mercaptopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, γ-aminopropyltrimethoxysilane, 3,4-
Epoxycyclohexylethyltrimethoxysilane,
Examples thereof include 3,4-epoxycyclohexylethyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, and diethyldimethoxysilane. Preferred are tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane and dimethyldiethoxysilane. As the cyclic siloxane, hexaphenylcyclotrisiloxane, octaphenylcyclotetrasiloxane, tetravinyltetramethylcyclotetrasiloxane, hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, pentamethylcyclotetrasiloxane, hexamethylcyclotetrasiloxane. In addition to cyclic compounds such as tetramethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, and trimethyltriphenylcyclotrisiloxane, linear or branched organosiloxanes can be mentioned. These organosilane compounds may be used alone or in combination of 2
One or more species can be used in combination, and it can also be used in combination with other metal alkoxides such as titanium and aluminum. Further, these organosilane compounds can be used by dissolving them in an organic solvent, if necessary.

Next, a preferred method for producing the polymer fine particles for ink jet recording ink of the present invention will be described. First,
The polymerizable monomer is preferably polymerized by the emulsion polymerization method to obtain polymer particles (A). The average particle size of the polymer particles (A) at this time is not particularly limited, and the polymer is used so that the target average particle size of the finally obtained polymer fine particles for inkjet recording ink can be obtained. The average particle size of the particles (A) is appropriately determined. The average particle size of the polymer particles (A) can be controlled by the amount of emulsifier, stirring, and other known methods. The polymerization initiator used in the above emulsion polymerization is not particularly limited as long as it is used in ordinary emulsion polymerization and suspension polymerization, but potassium persulfate, sodium persulfate, persulfate salts such as ammonium persulfate are used. The initiator, azo-based initiator, hydrogen peroxide, organic peroxide and the like may be used alone or in combination with various reducing agents such as ascorbic acid.

In the above emulsion polymerization, a suspension protective agent or a surfactant is used in order to enhance the stability of the polymerization reaction system. Usual surfactants can be used, for example, dodecylbenzene sulfonate, dodecyl sulfate, lauryl sulfate, dialkyl sulfosuccinate, polyoxyethylene alkyl phenyl ether sulfate, polyoxyethyne aralkyl propenyl. Examples thereof include anionic surfactants such as phenyl ether sulfate and formalin condensate of naphthalenesulfonic acid. Here, examples of the salt include sodium and ammonium. Furthermore, it is also possible to use nonionic surfactants such as polyoxyethylene nonylphenyl ether, polyethylene glycol monostearate, polyoxyethylene alkylpropenyl phenyl ether, sorbitan monostearate. Also,
It is possible to use a generally known reactive emulsifier such as sodium naphthalenesulfonate alone or in combination with the above-mentioned surfactant. As a preferable suspension protector, water-soluble polymers such as polyvinyl alcohol, polyvinylpyrrolidone, carboxymethyl cellulose, sodium polyacrylate, and hydroxypropyl cellulose can be used. These may be used alone or in combination. A preferable combination is a combination of an anionic surfactant, a nonionic surfactant and a water-soluble polymer.

Next, in the presence of the obtained polymer particles (A), usually 100 parts by weight of the polymer particles (A) are usually added.
0.1 to 900 parts by weight, preferably 10 to 300 parts by weight, particularly preferably 1 to 150 parts by weight, most preferably 2 to 100 parts by weight of the organosilane compound are condensed.
Here, the condensation reaction can be carried out in the presence of a solvent having a water solubility of 10 ⁻³ wt% or less. The solvent preferably includes ketones, lower alcohols, esters and the like. In the present invention, it is preferable to absorb the organosilane compound in the polymer particles (A), and as a method thereof, the organosilane compound is added all at once or continuously or in a divided manner in the presence of the organic polymer particles, It is achieved by stirring well. The organosilane compound absorbed by the organic polymer particles is 5% by weight or more, preferably 1% by weight or more of the total organosilane compound used.
It is 0% by weight or more, and more preferably 30% by weight or more.

Further, in order to prevent the reaction from proceeding in a state where the absorption of the organosilane compound is not sufficient, the inside of the reaction system is adjusted to pH 4 to 10, preferably pH 5 to 9, and more preferably pH 6 to 8, and the temperature is adjusted. It is desirable to add and absorb the organosilane compound under the conditions of 90 ° C or lower, preferably 70 ° C or lower, more preferably 50 ° C or lower, and particularly preferably 30 ° C or lower. The condensation reaction of the organosilane compound absorbed in the polymer particles (A) is easily controlled by changing the reaction temperature and the hydrogen ion concentration, and the degree of polymerization of polysiloxane can be adjusted. The condensation reaction of the organosilane compound can be carried out at a temperature of 30 ° C. or higher, preferably 50 ° C. or higher, more preferably 70 ° C. or higher. The polymer fine particles for inkjet recording ink of the present invention have a particle diameter of 0.01 to 0.2 μm,
It is preferably 0.01 to 0.15 μm, and more preferably 0.01 to 0.12 μm.

The polymer fine particles for ink jet recording ink of the present invention can be basically mixed with a dye (or pigment) and a medium to prepare an ink jet recording ink. Examples of dyes that can be used in the present invention include acid dyes, basic dyes, direct dyes, disperse dyes, and reactive dyes. Specifically, as the black dye, Direct Black # 19 (C.I.
5), Direct Black # 154, Hood Black #
2 (C.I. 27755), Solvent Black # 3,
Solvend Block # 22, Solvent Black # 23
Acid Yellow # 23 as a yellow dye
(CI.19140), Solvent Yellow # 19,
Solvent Yellow # 21, Solvent Yellow # 6
1, as a magenta dye such as Solvent Yellow # 80, Acid Red # 87 (CI.45380), Acid Red # 106 (CI.45100), etc., Solvent Red # 8, Solvent Red # 49, Solvent Red # 81, Solvent Red # 82, Solvent Red # 83, Solvent Red # 84, Solvent Red #SO 100, Solvent Red # 109, Solvent Red # 121, and the like, as a cyan dye, Acid Blue # 9 (CI. 42090), Direct Blue # 86 (C.I. 74180), Solvent Blue # 1
1, Solvent Blue # 12, Solvent Blue # 2
5, Solvent Blue # 36, Solvent Blue # 5
5, Solvent Blue # 73 and the like.

Further, as the pigment, those in which ordinary organic pigments or inorganic pigments are dispersed in fine particles are used, and those in which the particle diameter of the pigment is 0.1 μm or less are preferable. If the amount of the dye or pigment added is less than 0.5% by weight of the ink jet recording ink, sufficient color tone and density cannot be obtained, and if it exceeds 10% by weight, clogging is likely to occur. % Is preferred. Further, as the medium, water or other aqueous medium, for example, ethylene glycol, prolene glycol butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol 200, 400, 600, 150.
0, glycerin, n-methylolprolidone, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether and the like.
These aqueous media are usually added in an amount of 10 to 99% by weight of the inkjet recording ink. The polymer fine particles for an inkjet recording ink of the present invention have a total solid content of the inkjet recording ink of 0.1 to 90% by weight, preferably 1 to
70% by weight is added. In addition to the above, water-soluble polymers, polymer emulsions, surfactants, pH adjustors, antiseptic and antifungal agents, antirust agents, chelating agents, ultraviolet absorbers, infrared absorbers, etc. should be added to the inkjet recording ink. You can The ink jet recording ink using the polymer fine particles for ink jet recording ink of the present invention can be suitably used for printing on paper, woven cloth, non-woven cloth, plastic film and the like.

[0016]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited thereto. In the following description, "part" means "part by weight" and "%" means "% by weight". Examples 1 to 3 As the first step, monomers shown in Table 1 under nitrogen gas atmosphere, emulsifiers, 0.5 parts of ammonium persulfate as a polymerization initiator, 0.02 parts of sodium ethylenediaminetetraacetate as a chelating agent, an appropriate amount Polymerization stabilizer and water 2
Fifty parts were charged into a reaction vessel, and the monomers were emulsion-polymerized by a continuous addition method while stirring at a polymerization temperature of 60 to 80 ° C. In the second step, the temperature of the reaction vessel was continuously cooled to 25 ° C. and the pH was adjusted to 8 and then methyltrimethoxysilane 10 was added.
Parts were added and vigorously stirred for about 30 minutes. Then, the reaction container was heated to 70 ° C. and reacted for 3 hours to complete the condensation reaction to obtain polymer fine particles A to C containing polysiloxane. Comparative Example 1 Example 1 is the same as Example 1 except that the second step is not performed.
Polymer fine particles D for inkjet recording ink were obtained in the same manner as in.

[0017]

[Table 1]

Example 4 As a first step, divinylbenzene (commercial product, purity 55
%, The remaining 40% is ethyl vinyl benzene, the remaining 5%
Is diethylbenzene) 35 parts, styrene 55 parts, acrylic acid 10 parts, sodium dodecylbenzenesulfonate 1
5 parts, ion-exchanged water 900 parts and sodium persulfate 1
One part was placed in a reaction vessel and polymerized under stirring at 80 ° C. for 1 hour. Then, 30 parts of methyl methacrylate, n
-A mixed monomer consisting of 60 parts of butyl acrylate, 9 parts of methacrylic acid and 1 part of ethylene glycol methacrylate was continuously added over 3 hours to complete the polymerization. As the second step, the temperature of the reaction vessel is kept at 25 ° C.
After cooling to pH 8 and adjusting to pH 8, 40 parts of diethyldiethoxysilane was added, and the mixture was vigorously stirred for about 30 minutes. Then, the reaction container was heated to 70 ° C. and reacted for 3 hours to complete the condensation reaction to obtain polymer fine particles E for inkjet recording ink having an average particle diameter of 0.05 μm.

Test Example 1 Using the polymer fine particles A to E thus obtained, an ink jet recording ink having the following composition was prepared. As Comparative Example 2, an inkjet recording ink was prepared with the same composition as below except that no polymer fine particles for inkjet recording ink were used. Direct black # 19 3% Glycerin 4% Polymer fine particles A to E 10% Water 83% The above components are thoroughly mixed and stirred in a container, and filtered with a membrane filter having a pore size of 0.5 μm to prepare an inkjet recording ink. did. Printing was performed using the obtained inkjet recording ink using a commercially available inkjet printer, and the following evaluations were performed. The results are shown in Table 2. For evaluation, the paper is PP with a size degree of 17 seconds.
Using C form, stock form paper of size degree 16 seconds,
A commercially available OHP film was used as the evaluation film.

(1) Drying speed After printing for 5 seconds, the printed portion was rubbed with a finger and the presence or absence of deviation of the ink was observed. ◯: No misalignment was found between the two types of paper. X: A slight deviation is recognized on either of the two types of paper. (2) Sharpness After printing, bleeding of the screen and uneven density were visually observed. ◯: Both types of paper bleed at all and no density unevenness is observed. X: Bleeding and density unevenness are recognized even on either of the two types of paper. (3) Jetting stability After the ink was filled in the printer and left for 3 months, reprinting was performed to evaluate whether or not printing could be performed smoothly. ◯: Printing was successful. X: Clogging was observed in the nozzle and printing was impossible. (4) Water resistance After printing on PPC paper and film, the printed matter was immersed in water after 2 minutes, and bleeding on the screen was observed. ◯: No bleeding and no uneven density is observed. X: Bleed all over and uneven density is observed.

[0021]

[Table 2]

[0023]

INDUSTRIAL APPLICABILITY The ink jet recording ink using the polymer fine particles for ink jet recording ink of the present invention is excellent in quick-drying property and has printing characteristics such as bleeding, sharpness of contour, sharpness and durability, and nozzle ejection stability. Also excellent in water resistance of printed matter.

Front page continuation (72) Inventor Toru Masukawa 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd.

Claims (2)

[Claims] 1. Polymer fine particles for ink jet recording ink, comprising polysiloxane and having an average particle diameter of 0.01 to 0.2 μm. 2. Polymer fine particles for ink jet recording ink, which are obtained by condensation reaction of 0.1 to 900 parts by weight of an organosilane compound in the presence of 100 parts by weight of polymer particles.