JPH03225364A - Liquid developer for electrostatic charge image - Google Patents

Abstract

PURPOSE:To decrease the generation of gaseous hydrocarbon from a copying machine and to eliminate the need for application of oil on a fixing roll by dispersing toner particles contg. a resin in which a part of the main chains or side chains are connected into a specific carrier liquid mixture. CONSTITUTION:The developer is formed by dispersing the toner particles consisting of coloring agents and the resin into the carrier liquid consisting of the liquid mixture composed of a fluorine solvent and an aliphat. hydrocarbon solvent and/or silicone solvent and having a high resistance and low dielectric constant. The resin (A) in which a part of the main chains or side chains are connected by the interaction of an acid-salt is compounded into the above- mentioned resin. A (co)polymer contg. >=1 kinds of a monomer having an acidic group {e.g.: acrylic acid (deriv.)} and a monomer having a basic group (e.g.: vinyl pyridine) as its component is usable as the resin A.

Description

[Detailed description of the invention] [Industrial field]

The present invention relates to a liquid developer for hot roll fixing used in electrophotography, electrostatic/recording, electrostatic printing, etc. (Prior art) As a liquid developer for heat roll fixing rolls, JP-A-63
-301966 to 301969, 64-500
No. 62-50067, No. 64-52167, No. 64-
142560-142561, etc. Since these are carrier liquids mainly composed of aliphatic hydrocarbons, the aliphatic hydrocarbon gas is discharged outside the copying machine, and silicone oil must be supplied to apply to the fixing roll. There were problems such as the copying machine becoming more complex and the number of consumables increasing.

[Object of the present invention]

The purpose is to reduce hydrocarbon solvent gases generated from copying machines. To make it possible to remove an oil application device to a fixing roll in a hot roll fixing device using a liquid developer, and to save the trouble of oil supply. By mixing in a certain proportion of nonflammable liquid, the risk of ignition is reduced. [Structure of the Invention] In recent years, hot roll fixing has been proposed as a method of fixing a liquid developer that has high thermal efficiency and is capable of high-speed fixing. By using a hydrocarbon-based solvent as the carrier liquid and adopting this fixing method, the amount of solvent gas emitted per unit number of sheets is slightly reduced compared to the conventionally used atmospheric fixing, but it is possible to copy a large number of sheets at high speed. When this happens, a large amount of solvent gas is generated. Furthermore, it was necessary to apply silicone oil to improve the releasability between the toner layer and the fixing roll. The present invention aims to improve the above-mentioned drawbacks, increase the cohesive force of the toner, and prevent so-called "hot offset" by containing a fluorine-based solvent as a carrier liquid. Fluorinated solvents used in the present invention include Fluorinert FC-77, FC-40, FC-43, FC-70
(Manufactured by 3M Company), Afroud, E-10, E-1
6, E-18 (manufactured by Asahi Glass Co., Ltd.), and the like. Further, as silicone-based solvents that may be used at the same time, KF96 (Shin-Etsu Silicon J-Con), 5H200, 5H3
44 (Toshiba Silicon), TSF451 (Toshiba Silicon), etc. In addition, decamethyltetrasiloxane, octamethyltrisiloxane, etc. may be used. In addition, cyclohexane, n-
hexane, n-hebutane, n-octane, n-nonane,
Petroleum hydrocarbons such as isooctane, isododecane, ligroin, and mixtures thereof (commercially available products include Isopar E, G, H, L, and V manufactured by Exxon Chemical Co., Ltd., and Shellsol 71 and Solupesso 150 manufactured by Shell Oil Co., Ltd.) ), and these may be mixed and used as appropriate. In order to reduce the amount of transfer agent, the carrier liquid should be 10 cst or less, preferably 3 cst or less. In the present invention, one way to increase the cohesive force of the toner is to provide the toner resin component with an acid-base interaction. In the present invention, acid-base interactions are formed within a single polymer or between two or more polymers. Although the details of how acid-base interactions are formed between polymers are unknown, it is likely that acidic and basic functional groups in the polymer are attracted to each other, resulting in a type of interaction. It is thought that by creating an association state, it apparently behaves like a resin molecule. It is believed that the acid-salt reaction between the functional groups forms a weak crosslinking state, which improves offset resistance while keeping the fixing temperature low. Acidic groups that cause such association include carboxylic acids,
There are groups such as sulfonic acid, phosphonic acid, and sulfinic acid, and basic groups include hydroxyl group, pyridyl group, and amino group. A polymer having one type or two or more of these acidic groups and basic groups can be used in the present invention, and the polymer can be prepared by polymerization or copolymerization from monomers having the above-mentioned functional groups. It is created by synthesis or by introducing the above-mentioned functional group into a polymer through reaction. Examples of monomers having the above-mentioned functional groups include acrylic acid and its derivatives such as acrylic acid, methacrylic acid, α-ethyl acrylic acid, crotonic acid, and isocrotonic acid; maleic acid, fumaric acid, itaconic acid, citraconic acid, etc. Unsaturated dicarboxylic acids and derivatives thereof; For example, aminoalkyl acrylates and aminoalkyl methacrylates such as diethylaminoethyl methacrylate; For example, vinylpiperidine, vinylpyrazine, vinylpyridine, etc.; For example, aminostyrene, dimethylaminostyrene,
Styrene derivatives such as carboxystyrene and hydroxystyrene; for example, vinylsulfonic acid and its derivatives; acidic and basic monomers contained in polymers that can be used by copolymerizing with other known monomers; As for the proportion of 0.1 to 30% by weight, good results are obtained;
Particularly preferred is a content in the range of 20% by weight. Examples of comonomers that can be copolymerized with the above monomers include:
Styrene, α-methylstyrene, p-chlorostyrene,
vinylnaphthalene, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, acrylonitrile,
Substituted monocarboxylic acids with double bonds, such as methagrilonitrile, acrylamide, etc.; Gestyl derivatives of dicarboxylic acids with double bonds, such as dibutyl maleate, dimethyl maleate, etc.; e.g., vinyl chloride, vinyl acetate, Vinyl esters such as vinyl benzoate; ethylenic olefins such as ethylene, propylene, butylene, etc.; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, etc.; vinyl methyl ether, vinyl ethyl Vinyl ethers such as ether, vinyl isobutyl ether, etc.; aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, etc.; such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, etc. carboxylic acid ester having two double bonds, divinyl ether, divinyl sulfide,
Divinyl compounds such as divinyl compounds and compounds having three or more vinyl groups can be used alone or as a mixture. Furthermore, resins having the above functional groups in the main chain or at the ends thereof can also be used in the present invention, such as polyamide resins and polyester resins. As a coloring material that can be used in the present invention, Printex V
, Printex U, Printex G, Special Black 15, Special Black 4, Special Black 4-B (manufactured by Degussa), Mitsubishi #44, #30, M
R-11, MA-100 (manufactured by Mitsubishi Kasei), Raven 1035, Raven 1252, New Spect■ (manufactured by Columbia Carbon), Zigal 400.660
, Black Pearl 900.1100.1300, Mogul L (manufactured by Cabot) and other inorganic pigments 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 Yellow S, Naphthol Red, Linole Fast Yellow 2G, Permanent Red 4R, Brilliant First Scarlet, Hansa Yellow, Benzidine Yellow, Lysol Red, Lake Red C, Lake Red D, Brilliant Color Examples include organic pigments such as Mino 6B, Permanent Red F5R, Pigment Scarlet 3B Indigo, Thioindigo Oil Pink and Bordeaux 10B. The pigment can be treated by mixing and crushing the above pigment with the resin using a two-roll machine, a kneader flasher, or the like. Further, the following resins may be used together with the above resins. Eastman Chemical
al) manufactured by (N-10, N-11, N-12, N-14
, N-34, N-45, C-10, C-13°C-15
, C-16, E-10, E-11, E-12, E-14
, E-15) Manufactured by Mitsui Petrochemical Co., Ltd. (+10P, 220P, 220MP, 820MP, 41
0MP, 2] OMP, 310MP. Between 405P, 200P, 4202E, 4053E
) Manufactured by Mitsubishi Chemical Corporation (13IP, +5IP, 16IP, !7IP, E
300. E250P) manufactured by Sasol (formerly, H2, AI, A2.A3.A4) BASF (BAS
Manufactured by F) (OA WAX, A WAX) Manufactured by Petrolite (Pareco (B)
ARECO) 500. 2000. E-730,E-
2018, E-2020, E-1040, Petronava (
Petronaba) C, C-36゜C-400,
C-7500) Manufactured by Hoechst (PE580. PE130. PEDI 21,
PEDI 36, PED153. PED521.
PED522. PED534) Made by Union Carbide (DYNI, DYNF, DYN) I, DYNJ,
DYNK) Monsando (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 150.2) 0.220.250.2
60.3] 0.360°410, 420.450.46
0.550.560''), polypropylene and its modified products, carnauba wax, montan wax, candelilla wax, sugarcane wax, ocurie wax, beeswax, wood wax,
Natural resins such as natural wax such as bran wax, ester gum, hardened rosin, natural resin modified maleic acid resin, natural resin modified phenol resin, natural resin modified polyester resin, natural resin modified pentaerythritol resin, epoxy resin, etc. Modified hardening resins etc. can be used together. Further, the dispersing resin preferably used in combination with the present invention includes a vinyl monomer A having the general formula % (R represents H or CH, and n represents an integer from 6 to 20) and the general formula % Vinyl monomers represented by the formula %)) and vinylpyridine, vinylpyrrolidone, ethylene glycol dimethacrylate,
Examples include copolymers and graft copolymers of each type of monomer B selected from styrene, divinylbenzene, and vinyltoluene, or several types of monomers. When a silicone solvent is contained as a carrier liquid, a silicone material having an acroyl group such as L34080 manufactured by Shin-Etsu Silicon Co., Ltd. may be copolymerized to improve its dispersibility, or AK manufactured by Toagosei Chemical Co., Ltd. -5, Chisso TMO701, FMO711, FMO721
, FMO725 may also be used. These coloring materials, resins, and carrier liquids are put into a dispersing machine such as a ball mill, kitty mill, disk mill, and bottle mill, dispersed, and mixed to prepare a concentrated toner, and then dispersed in the carrier liquid of the present invention. A developer can be obtained by [Example] In the following examples, "1 part" represents "part by weight." Production Example 1 40 parts of toluene was placed in a separable flask, and 75 parts of styrene, 20 parts of butyl methacrylate, 5 parts of maleic acid, and 0.5 parts of divinylbenzene were added, and after replacing the gas phase with nitrogen gas, the temperature was heated to 80°C. 0.3 parts of benzoyl peroxide dissolved in 10 parts of toluene was replaced with nitrogen gas over 30 minutes, and then added dropwise using a funnel.
The mixture was further stirred at 80°C for 10 hours. Next, a toluene solution containing 0.3 parts of benzoyl peroxide 5
Parts by weight were added dropwise, the temperature was further raised to 90°C, and the temperature was maintained for 5 hours to complete polymerization. After cooling, the polymer was precipitated in a large amount of methanol, and the precipitate was filtered off, dried at 60° C., and collected. M w / M n of this polymer is 2
4, the Mw was 216,000. Production Example 2 Monomers: 75 parts of styrene, 20 parts of butyl methacrylate, 5 parts of 4-vinylpyridine, 0 parts of divinylbenzene
．． 5 parts were polymerized using the same method as above. M w /
Mn was 18 and Mw was 197.000. Production Example 3 Synthesis was carried out in the same manner as Production Example 1, except that 60 parts of styrene, 10 parts of methyl methacrylate, 20 parts of butyl acrylate, 10 parts of methacrylic acid, and 0.7 parts of divinylbenzene were used as monomers. Mw/Mn was 40 and Mw was 324,000. Example 1 70 parts of the resin of Production Example 1 50 parts of the pulverized product 200 parts of Isopar H (trade name of EXXSON) were placed in a ball mill and dispersed for 24 hours, and then 300 parts of Isopar H was added and dispersed for 1 hour. It was made into a concentrated toner. 200 g of this was taken and diluted in a mixed solvent 1a of 50% Fluorinert FC-72 (manufactured by 3M Co., Ltd.) and 50% KF96 (manufactured by Shin-Etsu Silicone Co., Ltd., viscosity 3cst) to prepare a developer. Example 2 Resin of Production Example 2 70 parts 250
8 parts of P (polyethylene made by Kochu Kasei Co., Ltd.) and 35 parts of A60 (carbon black made by Mitsubishi Kasei Co., Ltd.) were mixed with a flasher and then pulverized. 60 parts of the ground material and 8,100 parts of Isopar were placed in a ball mill and dispersed for 24 hours, and then 300 parts of Isopar H was further added and dispersed for 1 hour to obtain a concentrated toner. Take 200g of this and use Fluorinert FC-72.
It was diluted in a mixed solvent IQ (manufactured by 3M) and 50% Isopar H to prepare a developer. Example 3 Resin of Production Example 2 70 parts AC4
10 parts of 00A (manufactured by Allied Chemical Co., Ltd.) and 30 parts of Sorel 40o (manufactured by Cabot Company) were subjected to cross-wire pulverization at 140° C. for 60 minutes in a flasher. A developer was prepared in the same manner as in Example 1. An oil-less fixing test was carried out using a test machine, CT5085 manufactured by Ricoh, whose fixing unit was improved to a hot roll fixer. The results were as shown in the numerical table. As is clear from the above results, it can be seen that the developer of the present invention provides a temperature within the range in which heat roller fixation is possible without an offset phenomenon, and that heat roller fixation is possible. Continuous copying was performed using a test copying machine in a sealed room, and the solvent gas concentration was measured.
While it was 0 ppm, the developer of the present invention was halved to 80 to 150 ppm. [Effect 1] By using the developer of the present invention, it is possible to perform hot roll fixing without applying oil to the fixing roll and without causing an offset phenomenon, enabling high-speed, low-energy, constant fixing in a compact copying machine. It has become possible. Additionally, the amount of hydrocarbon gases generated by copying machines has also been reduced.

Claims (1)

[Claims] An electrostatic charge image in which toner particles made of a colorant and resin are dispersed in a carrier liquid of high resistance and low dielectric constant made of a mixed liquid of a fluorine-based solvent, an aliphatic hydrocarbon solvent, and/or a silicone-based solvent. 1. A liquid developer for electrostatic images, characterized in that the liquid developer contains a resin in which a part of the main chain or side chain is linked by acid-base interaction.