JPH05257332A - Electrophotographic developer - Google Patents

Abstract

(57) [Summary] [Object] To provide a developer for electrophotography, which has high image density, excellent solid uniformity, does not cause offset, and is capable of high-speed and low-energy fixing. In a developer for electrophotography containing a colorant and a resin as a main component, the resin is obtained by polymerizing a raw material monomer containing a polymerizable silicon compound represented by the following chemical formula 1 as a main component in a non-aqueous solvent. An electrophotographic developer comprising the obtained non-aqueous silicon-containing polymer. [Chemical 1] R ₈ is H or CH ₃ , and n ₁ is 1 to 5
00 is an integer, and n ₂ is an integer of 1 to 10. )

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic recording,
The present invention relates to an electrophotographic developer used for electrostatic printing or the like, and particularly to a developer for fixing on a heat roll.

[0002]

2. Description of the Related Art In recent years, thermal roll fixing has been proposed as a fixing method for liquid developers which has high thermal efficiency and enables high-speed fixing. If a hydrocarbon-based solution is used as the carrier liquid and this fixing method is adopted, the amount of solvent gas discharged per unit number of sheets will be slightly reduced compared to the conventional atmosphere fixing method, but multiple sheets can be copied at high speed. When it does, a large amount of solvent gas is generated. Further, it was necessary to apply silicone oil in order to improve the releasing property between the toner layer and the fixing roll.

As a liquid developer for heat roll fixing, there are disclosed in Japanese Patent Laid-Open Nos. 63-301966 to 301969 and 64-64.
50062-50067, 64-52167, 64-142560-142561 and the like.
Since these are carrier liquids containing aliphatic hydrocarbons as a main component, the gas of the aliphatic hydrocarbons is discharged to the outside of the copying machine, and the silicone oil for applying to the fixing roll must be supplied. There were problems such as the machine becoming complicated and the number of consumable items increasing.

[0004]

SUMMARY OF THE INVENTION The present invention makes it possible to remove an oil coating device from a fixing roll in an electrophotographic developing device, particularly a heat roll fixing device using a liquid developer, and to reduce the labor of oil supply. It is an object of the present invention to provide an electrophotographic developer capable of obtaining high image quality by omitting the above, and preventing "hot offset".

[0005]

According to the present invention, a colorant and an electrophotographic developer containing a resin as a main component are prepared by the following procedure in the presence of a polymerization initiator in a non-aqueous solvent. There is provided a developer for electrophotography, comprising a non-aqueous silicon-containing polymer obtained by polymerizing a raw material monomer containing a polymerizable silicon compound represented by Chemical formula 1 as a main component.

[Chemical 1] Selected from all or different from each other, part or all may be the same, R ₈ is H or CH ₃ , and n ₁ is 1 to 1
500 integer, n ₂ represents an integer of 1 to 10. )

As a result of intensive studies on the electrophotographic developer, the present inventors have found that as a resin constituting the electrophotographic developer, a raw material monomer containing a polymerizable silicon compound represented by the above chemical formula 1 as a main component. By using a non-aqueous silicon-containing polymer obtained by polymerizing in a non-aqueous solvent,
The inventors have found that the above objects can be achieved and completed the present invention.

In the polymerization of the raw material monomer containing the polymerizable silicon compound represented by the above chemical formula 1 as the main component,
As a result of research on a non-aqueous solvent such as a polymerization solvent for silicone oil, improvement in the polymerization rate, water repellency, oil repellency, and electrical insulation were observed. This is presumably because silicone oil has a higher purity than general organic solvents and radicals are less likely to be trapped in the polymerization solvent. Further, the obtained polymer was found to have improved water repellency, oil repellency, and electrical insulation. Silicone oil as a polymerization solvent participates in a part of reaction during polymerization of raw material monomers (methyl group of silicone oil). It is thought to be because of the polymerization by hydrogen abstraction reaction).

In the present invention, the resin constituting the developer is a polymer obtained by polymerizing a raw material monomer containing a polymerizable silicon compound as a main component and having a property similar to the solvent in a non-aqueous solvent. It is excellent in solubility or dispersibility in a non-aqueous solvent such as a solvent such as silicone oil, fluorine oil, and aliphatic hydrocarbon. When a polymer obtained by polymerizing a raw material monomer containing the polymerizable silicon compound represented by Chemical Formula 1 as a main component is used as the resin of the electrophotographic developer, offset does not occur in heat roll fixing.

Further, as the resin, R ₁ to
At least one group of R ₇ is —OH, —COOH, —
_{NH 2, -N (CH 3)} 2, -N (C 2 H 5) 2, - (C
_{H 2) 2 OH, - (} CH 2) 3 OH, - (CH 2) 2 -N
_{H 2, - (CH 2)} 2 N (CH 3) 2, - (CH 2) 2 N (C 2
_{H 5) 2, - (CH} 2) 3 -NH 2, - (CH 2) 3 -N (C
_{H 3) 2, - (CH} 2) 3 -N (C 2 H 5) 2, - (CH 2) 2
_{COOH, - (CH 2) 3} COOH, -C 6 H 5, when using the polymers obtained by polymerizing a raw material monomer mainly containing polymerizable silicon compound is a group selected from a halogen atom, Adsorption of the resin to the pigment or the like is improved, the dispersibility of the pigment is improved, and the polarity of the developer is stably maintained.

Furthermore, as the resin, R in the above Chemical Formula 1 is used.
_When a polymer obtained by polymerizing a raw material monomer whose main component is a polymerizable silicon compound in which at least one group of _{1 to} R ₇ is an acryloxy group or a methacryloxy group is used, image density and solid uniformity are improves. Moreover, since it is free to form a crosslinkable resin, a graft resin, and a microgel, dispersion stability, water repellency, oil repellency, and electric insulation are also improved.

The electrophotographic developer of the present invention will be described in more detail below. The polymerizable silicon compound represented by the above chemical formula 1 of the present invention is extremely important, and contributes to a polymerization reaction with a site having silicon in the skeleton that contributes to the affinity for solvents such as silicone oil and aliphatic hydrocarbons. It has a reactive site composed of a (meth) acryloxy group, has a low surface energy, and has the property of not having an adhesive force itself.

Typical examples of the polymerizable silicon compound represented by the chemical formula 1 of the present invention are shown in Table 1 below.

[Table 1]

As the resin constituting the electrophotographic developer of the present invention, a copolymerizable monomer can be used as a raw material monomer together with the polymerizable silicon compound represented by the above chemical formula 1, if necessary. Such copolymerizable monomers include vinyltoluene, nitrostyrene, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl methacrylate,
Diethylaminoethyl acrylate, styrene, p-methylstyrene, α-methylstyrene, 2,5-dichlorostyrene, α-vinylpyridine, acrylonitrile, vinyl acetate, vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl chloride, vinyl Carbazole, vinylpyrrolidone, vinylpyridine, vinylformal, vinylacetoacetal, vinylpropional, vinylbutyral, vinylhexylal, vinyl alcohol, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate,
n-butyl acrylate, n-butyl methacrylate,
iso-butyl acrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, lauryl methacrylate, stearyl methacrylate, dodecyl acrylate, methacrylic acid, acrylic acid, itaconic acid,
Maleic acid, divinylbenzene, ethylene glycol dimethacrylate, triethylene glycol triacrylate, glycidyl methacrylate, methacryloxyethyl phosphate, sulfoethylacrylamide, 2
-Hydroxyethyl methacrylate, acrylamide, etc. are exemplified.

The resin of the present invention can be manufactured as follows. The weight ratio of the polymerizable silicon compound represented by Chemical Formula 1 and a copolymerizable vinyl monomer, if necessary, is 5 to 100: 95 to 0, preferably 10 to 80:90 to.
It may be mixed in a ratio of 20 and a radical polymerization initiator may be added thereto and reacted in the polymerization solvent. In this case, if the amount of the polymerizable silicon compound is less than that, it is difficult to disperse in the silicone oil or the aliphatic hydrocarbon solvent, and the dispersibility of the pigment is poor. The polymerizable silicon compound and the copolymerizable vinyl monomer may be used alone or as a mixture of several kinds, and the radical polymerization initiator and the polymerization solvent may be similarly mixed and used. The ratio of solvent: raw material monomer: radical polymerization initiator is about 10-90: 10-90: 0.001-5 by weight. The reaction temperature and the reaction time vary depending on the kind of the raw material compound used, but generally, the suitable temperature is about 70 to 110 ° C., and the reaction time in this case is about 2 to 12 hours.

The silicone oil used as a polymerization solvent in the production of the non-aqueous silicon-containing polymer of the present invention includes:
Examples thereof include dialkyl silicone oils represented by Chemical Formula 2 below; cyclic polydialkyl siloxanes or cyclic polyalkylphenyl siloxanes; and alkylphenyl siloxanes. In addition, higher fatty acid modified silicone oil, methyl chlorinated phenyl silicone oil, alkyl modified silicone oil, methyl hydrogen silicone oil, amino modified silicone oil, epoxy modified silicone oil and the like can be used.

[Chemical 2] [However, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , and R ⁸ are -C
nH2n + 1 (n = 1 to 20), which may be the same or different. x is an integer of 0 or 1 or more. ]

When the dialkyl silicone oil represented by the above chemical formula 2 is used, there is an advantage that the temperature during polymerization can be freely selected. Of these, use of dimethylpolysiloxane is advantageous. The silicone oil represented by Chemical Formula 2 has a viscosity of 0.01 at 25 ° C.
It is preferably about 1,000,000 cs (centistokes). Furthermore, in the above Chemical Formula 2, x is 1 to 20,000.
The use of 0 is preferred. Furthermore, when a cyclic polydialkyl siloxane or a cyclic polyalkyl phenyl siloxane is used, the obtained resin has a drying property of the polymerization solvent, which is particularly advantageous for improving the coating property of the resin and providing gloss. is there. When an alkylphenyl siloxane (particularly, it is desirable to use methylphenyl silicone oil) is used, the solubility is improved by the introduction of a phenyl group (5 to 50 mol%), so that the dispersion stability of the resin solution is improved. It is advantageous to raise.

Specific examples of these various silicone oils are as follows. (I) Examples of dialkyl silicone oils: (II) Examples of cyclic polydialkyl siloxane and cyclic polyalkyl phenyl siloxane (contents of phenyl groups are 5, 10, 20, 50 mol%): cyclic polydimethyl siloxane, cyclic polymethyl phenyl siloxane cyclic polydiethyl siloxane, cyclic Polyethylphenyl siloxane Cyclic polydibutyl siloxane, Cyclic polybutylphenyl siloxane Cyclic polydihexyl siloxane, Cyclic polyhexyl phenyl siloxane Cyclic polydilauryl siloxane, Cyclic polymethyl chlorophenyl siloxane Cyclic poly distearyl siloxane, Cyclic polymethyl brom phenyl siloxane (III) Alkylphenyl Example of silicone oil: Examples of commercially available silicone oils include KF-96L (0.65, 1.0, manufactured by Shin-Etsu Chemical Co., Ltd.).
1.5, 2.0 centistokes (cs)), KF-9
6 (10, 20, 30, 50, 500, 1000, 30
00 (cs)), KF-56, KF-58, KF-54
Etc., TS manufactured by Toshiba Silicone Co., Ltd.
F451 series, TSF456 series, TSF41
0,411,440,4420,484,483,43
1,433 series, THF450 series, TSF4
04,405,406,451-5A, 451-10
A, 437 series, TSF440, 400, 401,
4300, 4445, 4700, 4450, 4702,
4730 series, TSF434, 4600 series,
Further, HS-200 manufactured by Toray Silicone Co., Ltd. and the like can be mentioned.

Other solvents can be mixed with the above silicone oil polymerization solvent to the extent that the characteristics of the silicone oil are not impaired. Such solvents include toluene,
Aromatic hydrocarbon solvents such as xylene and benzene; ethers and esters; alcohol solvents; n-hexane, n
-Octane, iso-octane, iso-dodecane, and aliphatic hydrocarbons such as a mixture thereof (commercially available from Exxon Chemical Co., Isopar HGLMV, etc.),
Mineral oil, vegetable oil, fatty acid ester, Maggie sol oil 9
0, Maggie Sol Oil 52 and the like. The mixing ratio of such other solvent is about 0.1 to 500 parts by weight with respect to 100 parts by weight of silicone oil.

The aliphatic hydrocarbon oil used in the present invention may be either a pure product or a mixture as long as it is a saturated aliphatic hydrocarbon which is liquid at room temperature and has a boiling point not lower than the polymerization temperature. It is common to use a mixed saturated aliphatic hydrocarbon having 6 or more carbon atoms from both sides, specifically, a mixture of hexane, octane, decane, dodecane, etc., or Isopar H, G, L, M manufactured by Exxon Chemical Co. , V, etc. are used. Incidentally, even when using an aliphatic hydrocarbon oil as a solvent, an aromatic solvent or ether, an ester, if necessary,
An oxygen-containing solvent of alcohol may be added, and the addition amount and the specific addition solvent are the same as those when using silicone oil.

When the silicone oil and the aliphatic hydrocarbon oil are used in combination, the silicone oil and the aliphatic hydrocarbon oil may be used by mixing them at any ratio within the range where both can be uniformly mixed. Also, by mixing a non-burning solvent,
The risk of ignition can be reduced.

All known radical polymerization initiators can be used, for example, benzoyl peroxide (BPO),
In addition to azobisisobutyronitrile (AIBN), lauryl peroxide, di-t-butyl peroxide,
Examples thereof include t-butyl-peroxide, cumene hydroperoxide, hydrogen peroxide, antimony persulfate, potassium persulfate, and phenylazotriphenylmethane. In addition, dimethylaniline, pyridine, C as a polymerization accelerator
O- or Mn-naphthenate can be used in combination.

The electrophotographic developer of the present invention uses a solvent for the non-aqueous carrier liquid in addition to the colorant and the resin. Examples of the non-aqueous carrier liquid solvent used in the present invention include KF96 (Shin-Etsu Silicon), SH200, SH344 (Toray Silicon), TSF451 (Toshiba Silicon), and the like.
In addition, decamethyltetrasiloxane, octamethyltrisiloxane, etc. may be used. In addition, as an aliphatic hydrocarbon solution, petroleum hydrocarbons such as cyclohexane, n-hexane, n-heptane, n-octane, n-nonane, isooctane, isododecane, ligroin, and mixtures thereof (commercially available from Isoxon Chemical Co. E, G, H, L, K, V, Shell Sol 71, Solubbeso 150 and the like manufactured by Shell Petroleum Co., Ltd.) and these are appropriately mixed or used alone. In order to reduce the amount of transfer agent, the carrier liquid has a viscosity of 10 cst or less, preferably 3 cst.
St or less is preferable.

The coloring agents usable in the present invention include Brintex V, Brintex U, Brintex G,
Special Black 15, Special Black 4, Special Black 4-B (all from Degussa), Mitsubishi # 4
4, # 30, MR-11, MA-100 (manufactured by Mitsubishi Kasei Co., Ltd.), Raven 1035, Raven 1252, News Spect II (manufactured by Columbia Carbon Co., Ltd.), Legal 400, 660, Black Bur 900, 1100,
1300, inorganic pigments such as Mogal L (all manufactured by Cabot Corporation) 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,
Resor Fast Yellow 2G, Permanent Red 4R, Brilliant First Scarlet, Hansa Yellow, Benzidine Yellow, Resor Red, Lake Red C, Lake Red D, Brilliant Carmine 6
Organic pigments such as B, permanent red F5R, pigment scarlet 3B indigo, thioindigo oil pink and Bordeaux 10B can be mentioned.

The above colorant and the above resin, two rolls,
The pigment can be treated by kneading and pulverizing with a kneader flasher or the like. Further, the following resin may be used together with the above resin. Eastman Chemical
al) (N-10, N-11, N-12, N-14, N-3
4, N-45, C-10, C-13, C-15, C-1
6, E-10, E-11, E-12, E-14, E-1
5) Mitsui Petrochemical Co., Ltd. (110P, 220P, 220MP, 820MP, 41
0MP, 210MP, 310MP, 405MP, 200
P, 4202E, 4053E) Sanyo Chemical Co., Ltd. (131P, 151P, 161P, 171P, E30
0, E250P) Made by Sazol (H1, H2, A1, A3, A4) Made by BASF (OA WAX, A WAX) Made by Petrolite (BARECO) 500, 2000, E- 7
30, E-2018, E-2020, E-1040, Petronaba C, the same C-36, the same C
-400, C-7500) Hoechst (PE580, PE130, PED121, PED13)
6, PED153, PED521, PED522, PE
D534) Union Carbide Co. (DYNI, DYNF, DYNH, DYNF, DYN
K) Monsanto (ORUZON 805, 705, 50) DuPont (ALATHON 3, 10, 12, 14,
16, 20, 22, 23) Allied Chemicals (AC polyethylene 6,6A, 615) Mitsui Polychemicals (Evaflex 150, 210, 220, 250, 2
60, 310, 360, 410, 420, 450, 46
0,560) and the like, synthetic polyesters, polypropylene and modified products thereof, natural waxes such as carnauba wax, montan wax, candelilla wax, sugar cane wax, aucurie wax, beeswax, wood wax and nuka wax, ester gum, Natural resin such as cured rosin, natural resin modified maleic acid resin, natural resin modified phenolic resin,
Natural resin modified polyester resin, natural resin modified pentaerythritol resin, natural resin modified cured resin such as epoxy resin, etc. can be used together.

These colorants, resins and solvents for carrier liquid are charged into a dispersing machine such as a ball mill, a kitty mill, a disc mill and a pin mill, dispersed and kneaded to prepare a concentrated toner, which is further used in the carrier liquid of the present invention. A developer can be obtained by dispersing in a solvent for use.

[0026]

EXAMPLES All "parts" in the following examples are "parts by weight".

Resin Synthesis Example-1 300 g of Isopar H was placed in a reaction vessel equipped with a stirrer, a thermometer, and a reflux condenser and heated to 90 ° C. In this solvent, 90 g of a polymerizable silicon compound (Compound 1 in Table 1),
2 g of a mixed solution of 40 g of 2-ethylhexyl methacrylate, 3 g of methacrylic acid and 3 g of azobisisobutyronitrile
After dropping for a while, polymerization was carried out at 90 ° C. for 4 hours. The resins of Synthesis Examples-2 to 8 were synthesized in the same manner as Synthesis Example-1 according to Table 2 below.

[Table 2]

Example 1 Nymeen S202 (trade name of amine component manufactured by NOF CORPORATION) 0.2 part Maleic acid / styrene / i-butyl 70 parts Acrylate copolymer (5/45/50) Carbon black (manufactured by Tegusa) 30 parts of Printex) was kneaded with a two-roll mill at 120 ° C. for 30 minutes and then pulverized. 50 parts of the pulverized product 100 parts of the resin of Synthesis Example-1 100 parts of Isopar H (trade name of EXXSON Co.) was 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. And 200 g of this was taken and diluted in Isopar H1l to obtain a developer.

Example 2 A developer of the present invention was prepared in the same manner as in Example 1 except that the resin of Synthesis Example-2 was used instead of the resin of Synthesis Example-1 of Example 1.

Example 3 A developer of the present invention was prepared in the same manner as in Example 1 except that the resin of Synthesis Example-3 was used instead of the resin of Synthesis Example-1 of Example 1.

Example 4 0.15 parts of Nymeen S202 Resin of Synthesis Example-4 80 parts 250P (polyethylene manufactured by Sanyo Chemical Co., Ltd.) 8 parts MA60 (carbon black manufactured by Mitsubishi Kasei) 35 parts were kneaded with a flasher and then pulverized. The pulverized product 60 parts Resin of Synthesis Example-5 200 parts Dimethyl silicone oil 115CS 100 parts This was carried out in the same manner as in Example 1 to obtain a developer.

Example 5 Resin of Synthesis Example-4 200 parts AC400A (manufactured by Allied Chemical Co., Ltd.) 10 parts Regal 400 (manufactured by Cabot Co.) 30 parts were kneaded and pulverized with a flasher at 140 ° C. for 60 minutes. After drying, the particles were dispersed to have an average particle size of 10 μm to prepare a dry toner.

An oilless fixing test was carried out with a test machine in which the fixing section of CT5085 manufactured by Ricoh was improved to heat roll fixing. The results are shown in Table 3 below.

[Table 3]

[0034]

As is clear from the above results, the electrophotographic developer of the present invention, when used in a heat roll fixing type copying machine, causes an offset even if silicone oil or the like is not applied. In addition, high speed and low energy fixing is possible. Further, when used in a dry / wet copying machine, the image density is high and the solid uniformity is excellent, and when used in a plate making developer, the etching property and the alkali resistance are excellent. In particular, when a polymerizable silicon compound having a polar group such as a carboxyl group is used as a raw material monomer of a resin that constitutes the developer, adsorption and dispersibility on a colorant and the like are further improved. When a polymerizable silicon compound having a plurality of reactive groups such as acryloxy groups is used as the raw material monomer, the image density and the solid uniformity are further improved.

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI Technical display location C08G 77/00 C08L 43/04 LKA 7921-4J G03G 9/087

Claims (3)

[Claims] 1. An electrophotographic developer containing a colorant and a resin as a main component, wherein the resin contains a polymerizable silicon compound represented by the following chemical formula 1 in the presence of a polymerization initiator in a non-aqueous solvent. An electrophotographic developer comprising a non-aqueous silicon-containing polymer obtained by polymerizing a raw material monomer as a main component. [Chemical 1] Selected from all or different from each other, part or all may be the same, R ₈ is H or CH ₃ , and n ₁ is 1 to 1
500 integer, n ₂ represents an integer of 1 to 10. ) 2. In the non-aqueous silicon-containing polymer, in the chemical formula ₁ , at least one group of R _{1 to} R ₇ is —OH, —CO.
_{OH, -NH 2, -N (CH} 3) 2, -N (C 2 H 5) 2, -
_{(CH 2) 2 OH, -} (CH 2) 3 OH, - (CH 2) -N
_{H 2, - (CH 2)} 2 N (CH 3) 2, - (CH 2) 2 N (C 2
_{H 5) 2, - (CH} 2) 3 NH 2, - (CH 2) 3 -N (C
_{H 3) 2, - (CH} 2) 3 -N (C 2 H 5) 2, - (CH 2) 2
_{COOH, - (CH 2) 3} COOH, -C 6 H 5, characterized in that it is a polymer obtained by polymerizing a raw material monomer mainly containing polymerizable silicon compound is a group selected from a halogen atom The electrophotographic developer according to claim 1. 3. The non-aqueous silicon-containing polymer is obtained by polymerizing a raw material monomer containing a polymerizable silicon compound as a main component, wherein at least one group of R _{1 to} R _{7 in} the chemical formula 1 is an acryloxy group or a methacryloxy group. The electrophotographic developer according to claim 1, which is a polymer obtained by the above process.