JP2826853B2 - Liquid developer for electrostatic image - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial fields]

The present invention relates to a hot roll fixing liquid developer used for electrophotography, electrostatic recording, electrostatic printing, and the like.

[Prior art]

As a liquid developer for heat roll fixing roll,
Nos. 301966 to 301969 and 64-50062 to 50067 and 64
-52167 and 64-142560 to 142561.
Since these are carrier liquids mainly composed of aliphatic hydrocarbons, the oil of the aliphatic hydrocarbons is discharged out of the copying machine, and silicone oil must be supplied for application to a fixing roll. There have been problems such as a complicated copying machine and an increase in the number of consumables.

[Object of the present invention]

An object of the present invention is to reduce a hydrocarbon solvent gas generated from a copying machine. In a hot roll fixing device using a liquid developer, an oil applying device can be removed from the fixing roll, and the trouble of oil supply can be eliminated. By mixing incombustible solvent at a certain ratio, danger such as ignition is reduced.

Configuration of the Invention

In recent years, a hot roll fixing method has been proposed as a fixing method of a liquid developer having high thermal efficiency and capable of high-speed fixing. When a hydrocarbon solvent is used as the carrier liquid and this fixing method is employed, the amount of solvent gas discharged per unit number is slightly reduced as compared with the conventionally used atmosphere fixing method, but a large number of copies were made at high speed. Sometimes a large amount of solvent gas is generated. Further, in order to increase the releasability between the toner layer and the fixing roll, it was necessary to apply silicone oil. An object of the present invention is to use a silicone-based solvent as a carrier liquid, improve the above-mentioned drawbacks, increase the cohesive force of the toner, and prevent so-called "hot offset". As the silicone solvent used in the present invention, KF
96 (Shin-Etsu Silicon), SH200, SH344 (Toray Silicon),
TSF451 (Toshiba Silicon) and the like, and decamethyltetrasiloxane, octamethyltrisiloxane and the like may be used. As the aliphatic hydrocarbon solution, petroleum hydrocarbons such as cyclohexane, n-hexane, n-heptane, n-octane, n-nonane, isooctane, isododecane, ligroin, and mixtures thereof (as commercial products, Isopar manufactured by Exxon Chemical Co., Ltd.) E, G, H, L, K, V
Shell Shell 71, Solbesso 150, and Shell Oil
And the like are used as appropriate.
In order to reduce the amount of the transfer agent, the carrier liquid should be 10 cst or less, preferably 3 cst or less. In the present invention, a polymer obtained by crosslinking a vinyl polymer having a carboxyl group with an amine is used as a means for increasing the cohesive strength of the toner. Examples of the carboxyl group-containing monomer for the vinyl polymerization synthesis include, for example, acrylic acid, methacrylic acid, α-
Ethyl acrylic acid, acrylic acid such as crotonic acid and α- or β-alkyl derivatives thereof, fumaric acid, maleic acid, unsaturated dicarboxylic acids such as citraconic acid and monoester derivatives thereof, and the like. By mixing and copolymerizing with another monomer, a polymer containing a desired carboxyl group can be produced. Examples of the monomer copolymerizable with the carboxyl group-containing monomer as described above include, for example, styrene, α-methylstyrene, p-chlorostyrene, vinylnaphthalene, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, Substituted monocarboxylic acid having a double bond such as octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide and the like;
For example, diester derivatives of dicarboxylic acids having a double bond such as dibutyl maleate, dimethyl maleate and the like; vinyls such as vinyl chloride, vinyl acetate, vinyl benzoate and the like;
Ethylene olefins such as butylene; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; vinyl benzene, divinyl Aromatic divinyl compounds such as naphthalene; carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate; divinyl aniline, divinyl ether And divinyl compounds such as divinyl sulfide and divinyl sulfone, and compounds having three or more vinyl groups can be used alone or as a mixture. As the ratio of the carboxyl group-containing monomer contained in the polymer having a carboxyl group, 0.1 to 30% by weight gives a good result, and when it is in the range of 0.5 to 20% by weight, a particularly preferable result is obtained. Next, in the present invention, the amine having the following general formula is preferably used as the amine for crosslinking the polymer having a carboxyl group. In the formula, a and b represent an integer of 2 to 4 and may be the same or different, x and y represent an integer of 1 to 50, and may be the same or different, and R is 8 to 30 (However, includes a branched and cycloalkyl group). The amount of the amine is about 0.1 to 100 parts by weight of the polymer.
0.5 parts by weight is preferred. Colorants that can be used in the present invention include Printex V, Printex U, Printex G, Special Black 15, Special Black 4, Special Black 4-B (manufactured by Degussa), Mitsubishi # 44, # 30, MR -1
1, MA-100 (Mitsubishi Kasei), Raven 1035, Raven 1252, Newspect II (Columbia Carbon), Legal 400, 660, Black Pearl 900, 110
Inorganic pigments such as 0, 1300, Mogar L (from Cabot) and phthalocyanine blue, phthalocyanine green, sky blue, rhodamine lake, malachite green lake, methyl violet lake, peacock blue lake, naphthol green B, naphthol green Y, naphthol green Yellow S, naphthol red,
Lisor First Yellow 2G, Permanent Red 4
Organic pigments such as R, Brilliant First Scarlet, Hansa Yellow, Benzidine Yellow, Lisor Red, Lake Red C, Lake Red D, Brilliant Carmine 6B, Permanent Red F5R, Pigment Scarlet 3B Indigo, Thioindigo Oil Pink and Bold-10B. Can be The pigment can be processed by kneading and pulverizing the above pigment with the resin by using a two-roll mill, a kneader flasher or the like. Further, the following resin may be used together with the above resin. Eastman Chemical (N-10, N-11, N-12, N-14, N-34, N-45, C-10, C-1
3, C-15, C-16, E-10, E-11, E-12, E-14, E-15) manufactured by Mitsui Petrochemical Co., Ltd. (110P, 220P, 220MP, 820MP, 410MP, 210MP, 310MP, 405MP, 20
0P, 4202E, 4053E) Sanyo Chemical (131P, 151P, 161P, 171P, E300, E250P) Sasol (H1, H2, A1, A2, A3, A4) BASF (OA WAX, A WAX) manufactured by Petrolite (BARECO 500, 2000, E-730, E-2018, E-202
0, E-1040, Petronaba C, C-36, C-
400, same C-7500) Hoechst (PE580, PE130, PED121, PED136, PED153, PED521, PED522, P
ED534) manufactured by Union Carbide (DYNI, DYNF, DYNH, DYNJ, DYNK) Monsanto (ORUZON 805,705,50) Dupont (ALATHON 3,10,12,14,16,20,22,23) Allied Chemical Company (AC polyethylene 6,6A, 615) Mitsui Polychemical Company (Evaflex 150,210,220,250,260,310,360,410,42
0,450,460,550,560) Synthetic polyesters such as polypropylene, modified polyesters thereof, carnauba wax, montan wax, candelilla wax, sugar cane wax, ocully wax, natural wax such as beeswax, wood wax, nuka wax, ester gum, cured rosin, etc. Natural resin, natural resin modified maleic resin, natural resin modified phenolic resin,
A modified natural resin such as a modified natural resin polyester resin, a modified natural resin pentaerythritol resin, or an epoxy resin can be used in combination. Further, the dispersing resin preferably used in combination in the present invention is represented by a general formula (R ₁ represents H or CH ₃ , n represents an integer of 6 to 20) and a vinyl monomer A represented by the following general formula: (R ₁ is H or CH ₃ , R ₂ is H, C _n H _{2n + 1} [n = 1 to 5], C ₂ H ₄ OH, Or C ₂ H ₄ N (C _m H _{2m + 1} ) ₂ [m = 1 to 4]. A) a vinyl monomer represented by the formula: vinyl pyridine, vinyl pyrrolidone, ethylene glycol dimethacrylate,
Each of the monomers B selected from styrene, divinylbenzene, and vinyltoluene may be used alone, or several types of copolymers and graft copolymers may be used. Silicon material with acroyl group to improve dispersibility in silicon solvent, LS4080 manufactured by Shin-Etsu Silicon
Or the like, or similarly, AK-5 manufactured by Toa Gosei Chemical Co., Ltd., TM0701, FM0711, FM0721, FM07 manufactured by Chisso Corporation.
25 may be used. Put these coloring materials, resin and carrier liquid into dispersing machines such as ball mill, kitty mill, disk mill, pin mill, etc.
A developer can be obtained by dispersing and kneading to prepare a concentrated toner and dispersing the same in the carrier liquid of the present invention.

【Example】

In the following examples, "parts" all mean "parts by weight". Example 1 Nimeen S202 (trade name of amine component manufactured by NOF Corporation) 0.2 part Maleic acid / styrene / i-butyl acrylate copolymer (5/45/50) 70 parts Carbon black (Printex manufactured by Degussa Corporation) 30 parts The mixture was kneaded with a two-roll mill at 120 ° C. for 30 minutes and then ground. 50 parts of the pulverized product lauryl methacrylate / methyl methacrylate / methacrylic acid / glycidyl methacrylate (80/10 /
5/5) 100 parts of Isopar H 20% solution of copolymer 200 parts of Isopar H (trade name of EXXSON) was placed in a ball mill and dispersed for 24 hours. Then, 300 parts of Isopar H was further added and dispersed for 1 hour. Was used as a concentrated toner. Take 200g of this, KF96 (made by Shin-Etsu Silicon, viscosity 3cs
t) Diluted in 1 to obtain a developer. Example 2 Nimeen S202 0.15 part Methacrylic acid / styrene / n-butyl acrylate copolymer (10/30/60) 57 parts 250P (polyethylene manufactured by Sanyo Chemical Co., Ltd.) 8 parts MA60 (carbon black manufactured by Mitsubishi Chemical Corporation) 35 parts After kneading with a flasher, the mixture was ground. 60 parts of the pulverized product stearyl methacrylate / methyl methacrylate /
Methacrylic acid / hydroxymethyl methacrylate (85/7
/ 4/4) Isopar H 10% solution of copolymer 200 parts Isopar H 100 parts A developer was obtained in the same manner as in Example 1. Example 3 Nimeen S202 0.2 part Maleic acid / styrene / n-butyl acrylate copolymer (8/42/50) 60 parts AC400A (manufactured by Allied Chemical) 10 parts Regal 400 (manufactured by Cabot) 30 parts at 140 ° C. The mixture was kneaded and crushed with a flasher for 60 minutes. Thereafter, a developer was prepared in the same manner as in Example 1. Comparative Examples Comparative Examples 1 to 3 were obtained in the same manner as in Examples 1 to 3, except that the diluent was ISOPAR H. An oil-less fixing test was performed using a testing machine in which the fixing unit of Ricoh CT5085 was modified to a hot roll fixing. The results are as shown in the following table. As is evident from the above results, the developer of the present invention has a temperature range within a range in which the heat roller can be fixed without exhibiting offset development, and it can be understood that the heat roll can be fixed. In a closed room, continuous copying was performed using a test copying machine, and the solvent gas concentration was measured.When the comparative developer was used, the concentration was 300 to 360 ppm, and in the case of the developer of the present invention, 80 to 300 ppm. It was halved to 150 ppm.

【effect】

By using the developer of the present invention, hot roll fixing can be performed without causing an offset phenomenon without applying oil to the fixing roll, and high-speed, low-energy fixing can be performed with a compact copying machine. . Also, the amount of hydrocarbon-based gas generated from the copying machine was reduced.

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hidemi Uematsu 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company, Ltd. (56) References JP-A-64-50066 (JP, A) JP-A Sho 63-4249 (JP, A) JP-A-50-80136 (JP, A) JP-B-41-6396 (JP, B1) JP-B-40-26990 (JP, Y1) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03G 9/13 G03G 9/125

Claims (1)

(57) [Claims] 1. A liquid developer for electrophotography comprising toner particles comprising a colorant and a resin dispersed in a carrier liquid having a high resistance and a low dielectric constant containing a silicon-based solvent as a main component. A liquid developer for an electrostatic image, comprising a polymer obtained by crosslinking a vinyl polymer having a carboxyl group with an amine.