JP3125813B2 - Electrophotographic developer - Google Patents

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 and the like, and particularly to a developer for fixing a hot roll.

[0002]

2. Description of the Related Art 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-based solution is used as the carrier liquid and this fixing method is used, the amount of solvent gas emitted per unit number is slightly reduced as compared with the conventionally used atmosphere fixing method. When this occurs, a large amount of solvent gas is generated. Further, in order to enhance the releasability between the toner layer and the fixing roll, it was necessary to apply silicone oil.

[0003] As a liquid developer for heat roll fixing, Japanese Patent Application Laid-Open Nos. 63-301966 to 301969, and 64-64
Nos. 50062 to 50067, 64 to 52167, and 64 to 142560 to 142561.
Since these are carrier liquids mainly composed of aliphatic hydrocarbons, the gas of the aliphatic hydrocarbons is discharged out of the copying machine, and it is necessary to supply silicone oil to be applied to the fixing roll. There were problems such as the machine becoming complicated and the number of consumables increasing.

[0004]

SUMMARY OF THE INVENTION The present invention makes it possible to remove an oil applying device from a fixing roll in an electrophotographic developing device, in particular, a hot roll fixing device using a liquid developer, and to reduce the time required for oil supply. It is an object of the present invention to provide an electrophotographic developer which can obtain high image quality by eliminating the problem and prevent "hot offset".

[0005]

According to the present invention, in a developer for electrophotography containing a colorant and a resin as main components, the resin is prepared by the following method in a non-aqueous solvent in the presence of a polymerization initiator. An electrophotographic developer 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 is provided.

Embedded image R ₈ may be H or CH ₃ , and n ₁ may be 1 to 4
500 integer, n ₂ represents an integer of 1 to 10. )

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

In the polymerization of a raw material monomer having a polymerizable silicon compound represented by the above formula 1 as a main component of the present invention,
Research on a non-aqueous solvent, for example, as a polymerization solvent for silicone oil, has been carried out. As a result, improvements in polymerization rate, water repellency, oil repellency, and electrical insulation have been found. This is thought to be because radicals are less likely to be trapped in the polymerization solvent due to the higher purity of silicone oil as compared with general organic solvents. Further, the obtained polymer was found to have improved water repellency, oil repellency, and electrical insulating properties because silicone oil as a polymerization solvent partially participates in the reaction during polymerization of the raw material monomers (methyl group of silicone oil). For example, polymerization by a hydrogen abstraction reaction).

In the present invention, the resin constituting the developer is a polymer obtained by polymerizing a raw material monomer mainly composed of a polymerizable silicon compound having properties similar to the solvent in a non-aqueous solvent. It has excellent solubility or dispersibility in non-aqueous solvents such as silicone oil, fluorine oil, aliphatic hydrocarbons and the like. When a polymer obtained by polymerizing a raw material monomer having a polymerizable silicon compound represented by Chemical Formula 1 as a main component is used as the resin of the electrophotographic developer, no offset occurs in hot 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
When a polymer obtained by polymerizing a raw material monomer having a polymerizable silicon compound as a main component selected from COOH, — (CH ₂ ) ₃ COOH, —C ₆ H ₅ , and a halogen atom is used, The resin adsorbability to pigments and the like is improved, the pigment dispersibility is improved, and the polarity of the developer is stably maintained.

Furthermore, as the resin, R
_When a polymer obtained by polymerizing a raw material monomer having as a main component 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 reduced. improves. In addition, since it is free to form a crosslinked resin, a graft resin, and a microgel, dispersion stability, water repellency, oil repellency, and electrical insulation are also improved.

Hereinafter, the electrophotographic developer of the present invention will be described in more detail. The polymerizable silicon compound represented by Chemical Formula 1 of the present invention is extremely important, and has a site having silicon in its skeleton that contributes to affinity for a solvent such as silicone oil or aliphatic hydrocarbon, and contributes to a polymerization reaction. It has a reaction site composed of a (meth) acryloxy group, has a low surface energy, and has a property of having no adhesive force itself.

The following Table 1 shows typical examples of the polymerizable silicon compound represented by the above formula (1) of the present invention.

[Table 1]

As the resin constituting the electrophotographic developer of the present invention, a copolymerizable monomer can be used together with the polymerizable silicon compound represented by the above formula 1 as a raw material monomer, if necessary. Examples of such a copolymerizable monomer include vinyl toluene, 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, vinyl pyrrolidone, vinyl pyridine, vinyl formal, vinyl acetoacetal, vinyl propional, vinyl butyral, vinyl hexylal, 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 and the like.

The resin of the present invention can be produced as follows. A weight ratio of the polymerizable silicon compound represented by the above formula 1 and a copolymerizable vinyl monomer, if necessary, of 5 to 100: 95 to 0, preferably 10 to 80:90 to
The mixture may be mixed at 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 this, it is difficult to disperse in a silicone oil or an 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 in a mixture of several kinds, and a radical polymerization initiator and a polymerization solvent may be used in the same manner. The ratio of the solvent: the raw material monomer: the radical polymerization initiator is about 10 to 90:10 to 90: 0.001 to 5 by weight. The reaction temperature and the reaction time vary depending on the type of the starting compound used, but generally the appropriate temperature is about 70 to 110 ° C, and the reaction time in this case is about 2 to 12 hours.

In the production of the non-aqueous silicon-containing polymer of the present invention, the silicone oil used as the polymerization solvent includes:
Dialkyl silicone oil represented by the following formula (2); cyclic polydialkylsiloxane or cyclic polyalkylphenylsiloxane; alkylphenylsiloxane and the like. 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.

Embedded image [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 0 or an integer of 1 or more. ]

When the dialkyl silicone oil represented by the above formula (2) is used, it is particularly advantageous that the temperature during polymerization can be freely selected. Among them, the use of dimethylpolysiloxane is advantageous. The silicone oil represented by Chemical Formula 2 has a viscosity at 25 ° C. of 0.01.
１，1,000,000 cs (centistokes) is preferred. Furthermore, in the above formula 2, x is from 1 to 20,000.
It is desirable to use what is 0. Further, when a cyclic polydialkylsiloxane or a cyclic polyalkylphenylsiloxane is used, the obtained resin has a drying property of a polymerization solvent, and is particularly advantageous for improving the coatability of the resin and giving gloss. is there. When alkylphenyl siloxane (especially, methylphenyl silicone oil is preferably used) is used, the solubility is improved by the introduction of phenyl groups (5 to 50 mol%), so that the dispersion stability of the resin solution is improved. This is advantageous for raising

Specific examples of these various silicone oils are as follows. Examples of (I) dialkyl silicone oil: (II) Examples of cyclic polydialkylsiloxane and cyclic polyalkylphenylsiloxane (the content of phenyl groups is 5, 10, 20, and 50 mol%, respectively): cyclic polydimethylsiloxane, cyclic polymethylphenylsiloxane cyclic polydiethylsiloxane, cyclic Polyethylphenylsiloxane Cyclic polydibutylsiloxane, Cyclic polybutylphenylsiloxane Cyclic polydihexylsiloxane, Cyclic polyhexylphenylsiloxane Cyclic polydilaurylsiloxane, Cyclic polymethylchlorophenylsiloxane Cyclic polydistearylsiloxane, Cyclic polymethylbromophenylsiloxane (III) Alkylphenyl Examples of silicone oil: Commercially available examples of these silicone oils include KF-96L (0.65, 1.0,
1.5, 2.0 centistokes (cs)), KF-9
6 (10, 20, 30, 50, 500, 1000, 30
00 (cs)), KF-56, KF-58, KF-54
And 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 examples include HS-200 manufactured by Toray Silicone Co., Ltd.

The above-mentioned silicone oil polymerization solvent may be mixed with another solvent to such an extent that the properties of the silicone oil are not impaired. Such solvents include toluene,
Aromatic hydrocarbon solvents such as xylene and benzene; ethers, esters; alcohol solvents; n-hexane, n
Aliphatic hydrocarbons such as octane, iso-octane, iso-dodecane and mixtures thereof (commercially available products such as Isopar HGLMV manufactured by Exxon Chemical Company);
Mineral oil, vegetable oil, fatty acid ester, Maggie sol oil 9
0, Maggie sol oil 52 and the like. The mixing ratio of such another solvent is about 0.1 to 500 parts by weight with respect to 100 parts by weight of the silicone oil.

The aliphatic hydrocarbon oil used in the present invention can be used as a pure product or a mixture as long as it is a saturated aliphatic hydrocarbon which is liquid at ordinary temperature and has a boiling point higher 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, or the like, or Isopar H, G, L, M manufactured by Exxon Chemical Company. , V, etc. are used. In addition, when using an aliphatic hydrocarbon oil as a solvent, an aromatic solvent, ether, ester,
An oxygen-containing solvent of alcohol may be added, and the amount and specific solvent to be added 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 mixed and used in an arbitrary ratio as long as the two can be uniformly mixed. Also, by mixing incombustible solvents,
Danger such as ignition can be reduced.

As the radical polymerization initiator, any known radical polymerization initiator can be used, for example, benzoyl peroxide (BPO),
In addition to azobisisobutyronitrile (AIBN), lauryl peroxide, di-t-butyl peroxide,
t-butyl-peroxide, cumene hydroperoxide, hydrogen peroxide, antimony persulfate, potassium persulfate, phenylazotriphenylmethane and the like. In addition, dimethylaniline, pyridine, C
o- or Mn-naphthenate can be used in combination.

The electrophotographic developer of the present invention uses a solvent for a non-aqueous carrier liquid in addition to a colorant and a 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, or 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, and Shell Sole 71, Solvesso 150, etc., manufactured by Shell Petroleum Co., Ltd.). In order to reduce the amount of transfer agent, the viscosity of the carrier liquid should be 10 cst or less, preferably 3 cst.
st or less is good.

The coloring agents that can be used in the present invention include VINTEX V, VINTEX U, VINTEX G,
Special Black 15, Special Black 4, Special Black 4-B (from Degussa), Mitsubishi # 4
4, # 30, MR-11, MA-100 (manufactured by Mitsubishi Kasei), Raven 1035, Raven 1252, Newspect II (manufactured by Columbia Carbon), Regal 400, 660, Blackbar 900, 1100,
Inorganic pigments such as 1300, 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,
Lisor First Yellow 2G, Permanent Red 4R, Brilliant First Scarlet, Hansa Yellow, Benzidine Yellow, Lisor Red, Lake Red C, Lake Red D, Brilliant Carmine 6
B, permanent red F5R, pigment scarlet 3B indigo, thioindigo oil pink, and organic pigments such as Bordeaux 10B.

The above-mentioned colorant is added to the above-mentioned resin and 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) (131P, 151P, 161P, 171P, E30) manufactured by Sanyo Chemical Industries, Ltd.
0, E250P) manufactured by Sasol (H1, H2, A1, A3, A4) manufactured by BASF (OA WAX, A WAX) manufactured by Petrolite (BARECO 500, 2000, E-) 7
30, E-2018, E-2020, E-1040, Petronaba C, C-36, C
-400, C-7500) manufactured by Hoechst (PE580, PE130, PED121, PED13
6, PED153, PED521, PED522, PE
D534) manufactured by Union Carbide (DYNI, DYNF, DYNH, DYNF, DYN
K) 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, 2)
60, 310, 360, 410, 420, 450, 46
0,560) and the like, natural waxes such as carnauba wax, montan wax, candelilla wax, sugar cane wax, ocully wax, beeswax, wood wax, nuka wax, ester gum, and the like. Natural resins such as cured rosin, modified natural resins, modified phenolic resins,
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.

The colorant, resin, and solvent for the carrier liquid are introduced 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. A developer can be obtained by dispersing in a solvent for use.

[0026]

EXAMPLES In the following examples, "parts" all mean "parts by weight".

Synthesis Example 1 of Resin 300 g of Isopar H was placed in a reaction vessel equipped with a stirrer, thermometer and reflux condenser, and heated to 90 ° C. In this solvent, 90 g of a polymerizable silicon compound (Compound 1 in Table 1)
A mixture of 40 g of 2-ethylhexyl methacrylate, 3 g of methacrylic acid, and 3 g of azobisisobutyronitrile was added to 2
After dropwise addition over a period of time, 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 in Synthesis Example 1 according to Table 2 below.

[Table 2]

Example 1 Nimeen 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) (Printex) 30 parts 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-1 200 parts of Isopar H (trade name of EXXXSON) 200 parts were placed in a ball mill and dispersed for 24 hours. Then, 300 parts of Isopar H was further added and dispersed for 1 hour. And 200 g of this was taken and diluted in 1 l of Isopar H 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 Nimeen S202 0.1 part of resin of Synthesis Example-4 80 parts 250 P (polyethylene manufactured by Sanyo Chemical Co., Ltd.) 8 parts 35 parts of MA60 (carbon black manufactured by Mitsubishi Kasei) were kneaded with a flasher and then pulverized. 60 parts of the pulverized product 200 parts of the resin of Synthesis Example-5 100 parts of dimethyl silicone oil 115CS 100 parts A developer was obtained in the same manner as in Example 1.

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

A fixing test was carried out using an oil-less test machine in which the fixing section of Ricoh CT5085 was modified to a hot roll fixing. The results are shown in Table 3 below.

[Table 3]

[0034]

As is apparent from the above results, when the electrophotographic developer of the present invention is used in a hot roll fixing type copying machine, an offset is generated without applying silicone oil or the like. And high-speed, low-energy fixing is possible. In addition, 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, it has excellent etching properties and alkali resistance. In particular, when a polymerizable silicon compound having a polar group such as a carboxyl group is used as a raw material monomer of the resin constituting the developer, adsorption and dispersibility to a coloring agent and the like are further improved. When a polymerizable silicon compound having a plurality of reactive groups such as an acryloxy group is used as the raw material monomer, the image density and solid uniformity are further improved.

Continuation of the front page (56) References JP-A-56-1060 (JP, A) JP-A-3-105351 (JP, A) JP-A-4-198943 (JP, A) JP-A-4-163464 (JP) JP-A-62-108262 (JP, A) JP-A-3-105352 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/08, 9/12

Claims (3)

(57) [Claims] 1. An electrophotographic developer comprising a colorant and a resin as main components, wherein the resin comprises a polymerizable silicon compound represented by the following formula 1 in a non-aqueous solvent in the presence of a polymerization initiator. An electrophotographic developer comprising a non-aqueous silicon-containing polymer obtained by polymerizing a raw material monomer as a main component. Embedded image R ₈ may be H or CH ₃ , and n ₁ may be 1 to 4
500 integer, n ₂ represents an integer of 1 to 10. ) 2. The non-aqueous silicon-containing polymer according to the above chemical formula 1, wherein at least one of R _{1 to} R ₇ is —OH, —CO 2
_{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, wherein 3. The non-aqueous silicon-containing polymer polymerizes a raw material monomer mainly composed of a polymerizable silicon compound in which at least one of R _{1 to} R ₇ is an acryloxy group or a methacryloxy group. 2. The electrophotographic developer according to claim 1, wherein the developer is a polymer obtained by the above method.