JPS63301969A - Electrostatic charge image developing liquid developer - Google Patents

Abstract

PURPOSE:To obtain a developer not causing offset trouble at the time of using a heat roll fixing system capable of high-speed fixing by using a rosin-modified cross-linked polyester. CONSTITUTION:The liquid developer contains the rosin-modified cross-linked polyester to be used is prepared by allowing to react with (I) rosin glycidyl ester as a resin (II) dicarboxylic acid or its anhydride, (III) at least one of a group of a polyfunctional epoxy compound, a trivalent or higher polybasic acid or its anhydride, and a trivalent or higher polyol, and (IV) a diol, and has a softening point of 50-190 deg.C, a glass transition point of 10-170 deg.C, and a molecular weight of 2,000-40,000, thus permitting the obtained developer not to cause offset trouble and to be easy in high-speed fixing.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a liquid developer used in electrophotography, electrostatic recording, electrostatic printing, etc.

[Prior art]

The fixing method for toners is an open fixing method in which the toner is passed through a heated atmosphere using an electric heater, a heated roll fixing method in which the toner is passed between a pair of rolls, at least one of which is a heated roll, or a toner is passed between a pair of rigid rolls at room temperature. A pressure fixing method in which the image is passed through is known.

Almost all copiers that used liquid developers used open fixing.

Among these fixing methods, the heated roll fixing method makes pressure contact between the surface of the heated roll and the toner on the fixing substrate.
Since the thermal efficiency when fusing a toner image onto a fixing substrate is extremely high and it can be fixed quickly, it is extremely suitable for image forming apparatuses particularly intended for high-speed copying.

In the heat roll fixing method, the toner is heated and molten and pressure-contacted to the surface of the heat roll, which causes a so-called offset phenomenon in which a portion of the toner adheres to the roll surface and then re-adheres to the substrate to be fixed, staining the image. There are drawbacks that can easily occur.

〔the purpose〕

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel liquid developer that does not cause offset development when using a hot roll fixing system that has high thermal efficiency and is capable of high-speed fixing.

〔composition〕

Generally, when a liquid developer is thermally fixed, the presence of a carrier liquid causes the toner particles to dissolve and swell in the carrier liquid, resulting in a further decrease in the cohesive force of the toner, resulting in what is called "hot offset".
tends to occur.

In order to solve the above problems, the present invention uses a crosslinked rosin-modified polyester.

As resin (1) rosin glycidyl ester, (II)
At least one crosslinking agent selected from the group consisting of dicarboxylic acid or dicarboxylic acid anhydride, (III) polyfunctional epoxy compound, trivalent or higher polybasic acid or its acid anhydride, and trivalent or higher polyhydric alcohol , and (IV)
The softening point obtained by reacting dihydric alcohol is 50~
190℃, glass transition point 10-170℃, molecular weight 2
The present invention relates to an electrophotographic toner composition containing a Japanese sulfur-based polymer compound having a molecular weight of 000 to 40,000.

The rosin glycidyl ester (1) used in the present invention can be prepared by subjecting rosin and epihalohydrin to a heating reaction in the presence of an alkaline substance such as an organic amine.

Examples of the rosin used include natural rosin such as gum rosin, wood rosin, and tall oil rosin, hydrogenated rosin obtained by modifying these rosins, and disproportionated rosin.

Naturally, organic components of rosin such as abietic acid, dehydroabietic acid, dihydroabietic acid, dihydroabietic acid, hismaric acid, and isophthalic acid can also be used.

The organic amines are preferably tertiary amines or onium salts thereof, and specific examples of the tertiary amines include triethylamine, dimethylbenzylamine, methyldibenzylamine, tribenzylamine, dimethylaniline, and dimethyldicyclohexylamine. , methyldicyclohexylamine, tripropylamine, tributylamine, N-phenylmorpholine, N-merylpiperidine, pyridine, and the like.

Specific examples of onium salts of tertiary amines include tetramethylammonium chloride, tetramethylammonium bromide, benzyltriethylammonium chloride, allyltriethylammonium bromide, tetrabutylammonium chloride, methyltrioctylammonium chloride, and trimethylamine hydrochloride. Examples include triethylamine hydrochloride, pyridine hydrochloride, and the like.

The dicarboxylic acid or dicarboxylic acid anhydride (hereinafter simply referred to as dicarboxylic acids) used in the present invention includes orthophthalic acid, isophthalic acid, terephthalic acid, endomethy-4=lentithrahydrophthalic acid, and tetrahydrophthalic acid. acids, methyltetrahydrophthalic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, maleic acid, fumaric acid,
Succinic acid, adipic acid, azelaic acid, sebacic acid, alkenylsuccinic acid having 8 to 10 carbon atoms, 6 to 18 carbon atoms
Mention may be made of these alkyl succinic acids and their acid anhydrides.

As the crosslinking agent (II) used in the present invention,
For example, the following compounds can be mentioned.

Examples of the polyfunctional epoxy compound include epoxy resins which are mixtures of bisphenol A and epihalohydrin, and rosin diepoxide or rosin triepoxide which are reaction products of acrylated rosin or fumarated rosin and epihalohydrin. The rosin used for the polyepoxide of the rosin is the same as that used for the rosin glycidyl ester.

Examples of trivalent or higher polybasic salts or anhydrides thereof include trimellitic acid, pyromellitic acid, and acid anhydrides corresponding thereto.

Examples of trihydric or higher polyhydric alcohols include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol.

Dihydric alcohol has other constituent components (1), (2) and (
It is used to adjust the glass transition point of the rosin-based polymer compound obtained by reacting n) and to improve the low-temperature fixability. The (mV) dihydric alcohol used in the present invention is not particularly limited, and includes, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol,
Examples include 3-butanediol, 1,4-butanediol, bisphenol, hydrogenated bisphenol A, ethoxylated bisphenol A, propoxylated bisphenol A, and bishydroxyethyl terephthalate.

The amount of dihydric alcohol to be used is appropriately determined in consideration of the glass transition point of the rosin-based polymer compound to be obtained. usually,
The dihydric alcohol is used to replace 1 to 70 mol% of the rosin glycidyl ester.

As a method for producing the rosin-based polymer compound used in the present invention, for example, rosin diglycidyl ester, the dicarboxylic acids, the crosslinking agent, and the dihydric alcohol are simultaneously charged, and in the presence of the organic amines as a reaction catalyst. Alternatively, a method of heating reaction in the absence of rosin glycidyl ester, dicarboxylic acids, and dihydric alcohol is carried out by heating in the presence or absence of organic amines, a crosslinking agent is added during or after the reaction, and further heating is performed. A method of proceeding with the reaction may be adopted.

In that case, the molar ratio of rosin glycidyl ester and dicarboxylic acids used is preferably 1:1, but 1.5
: 1.0 to 1.0 : It is also possible to set it within the range of 1.5. On the other hand, the amount of the crosslinking agent to be used has a significant effect on the properties of the resulting toner binder resin, particularly on the molecular weight and molecular weight distribution, and therefore must be appropriately and carefully determined.

The amount of polyfunctional epoxy compound used among the crosslinking agents is:
It may be determined by considering the number of functional groups of the compound, that is, the epoxy equivalent, and usually, when the total number of moles of rosin glycidyl ester and dicarboxylic acids is 1 mole, for example, for fumarized rosin triglycidyl ester, it is 0.
005 to 0.07 mol, preferably o, oos to 0.0
The amount is 4 moles. In addition, in the case of commercially available bisphenol type epoxy resin, o, oos to 0.14 mol, preferably 0.0
The amount is preferably 0.05 to 0.07 mol.

Similarly, considering the number of functional groups of polycarboxylic acids or polyhydric alcohols, the amount is usually 0.005 to 0.3 mole in the case of trihydric acids per 1 mole of the total of rosin glycidyl ester and dicarboxylic acid. , preferably 0.0
It is used within the range of 0.05 to 0.15 mol.

In the present invention, it is not necessarily necessary to react at the bottom left of the organic amine, but depending on the type of dicarboxylic acid used, it may be used to make the reaction time a single line. and 0.01 to 5% (weight%, the same applies hereinafter), preferably 0.
It is preferable to set it within the range of 0.05 to 1%.

As a coloring material that can be used in the present invention, Printex ■
, 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 Corporation), Raven 1035, Raven 1252, New Spectra ■
(manufactured by Columbia Carbon), Regal 400.6
Inorganic pigments such as 60, Black Pearl 900.1100.1300, Mogar Shikori (manufactured by 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 Yellow S, Naphthol Red, Resol Fast Yellow 2G, Permanent Red 4R, Brilliant Fast Scarlet, Hansa Yellow, Benzidine Yellow, Resol Red, Lake Red C, Lake Red D, Brilliant Carmen 6B, Permanent Red F5R , Pigment Scarlet 3B Indigo,
Examples include organic pigments such as 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) Company N-10, N-11, N-1, 2, N-14,
N-34, N-45, C-10゜C-13, C-15,
C-16, E-1, 0, E-11, E-12, E-14
゜E-15゜Mitsui Petrochemical Co., Ltd. 110P, 220P, 220MP, 820MP,
410MP, 210MP, 310MP.

405MP, 200P, 4202E, 4053E
Sanyo Chemical Co., Ltd. 13IP, 151P, 161P, 171P, E
300. E250P former Sasol company, H2, A1. , A2. A3. A4 bass (
BASF) company OA WAX, A WAX Petrolite company Bareco (BAR)
ECO) 500, BARECO (BARECO) 2000
゜E-730, E-2018, E-2020, E-10
40, Petronaba C, Petronaba C-36, Petronaba (Pe)
tronaba)C-400, Petronaba(Petro)
naba) Hoechst PE580. PE] 30. PED121. PED
136. PED153°PED521. PED52
2. PED534 Union Carbide DYNI, DYNF, DYNH, DYNJ, DY
NK Monsando ORLIZON 805.705.50 DuPont ALATHON 3, 10, 12, 14, 1
6,20,22.23 Allied Chemical Co., Ltd. AC polyethylene 6, 6A, 615 Mitsui Polychemical Co., Ltd. Evaflex 150.210.220.250.26
0°310, 360.410.420.450.460
．． Synthetic polyesters such as 550.560, polypropylene and its modified products, carnauba wax, montan wax, candelilla wax, sugar cane wax, auriculie wax, natural waxes such as poaching, wood wax, bran wax, ester gum, hardened rosin, etc. Natural resins, natural resin-modified maleic acid resins, natural resin-modified phenolic resins, natural resin-modified polyester resins, natural resin-modified pentaerythritol resins, epoxy resins, and other natural resin-modified hardened resins.

The dispersing resin of the present invention includes (hereinafter blank) vinyl monomer A represented by the general formula, vinyl monomer represented by the general formula, vinyl pyridine, vinyl pyrrolidone, ethylene glycol dimethacrylate,
Each type of monomer B selected from styrene, divinylbenzene, and vinyltoluene, or several types of copolymers and graft copolymers are used.

The amount of the dispersing resin used is usually 0.1 to 3 parts by weight, preferably 0.5 parts by weight, per 1 part by weight of the resin component that is a feature of the present invention.
It is used in a proportion of ~1.5 parts by weight.

Further, the total amount of resin components that may be present in the toner composition is 5 to 100 parts by weight, preferably 5 to 100 parts by weight, based on 100 parts by weight of the liquid component.
~20 parts by weight.

As the carrier liquid, cyclohexane, n-hexane, n-
Hebutane, n-nonane, n-octane, isooctane,
Petroleum-based aliphatic hydrocarbons such as indodecane, ligroin, and mixtures thereof (commercially available products include Isopar E, G, H, and L manufactured by Esso Standard Oil Co., Ltd., and Shellsol 71 and Turupez 150 manufactured by Niya Shell Sekiyu Co., Ltd.) is used.

These coloring materials, resins, and carrier liquids are introduced into a dispersing machine such as a ball mill, Kitty mill, disk mill, pin mill, or vibration mill, and are dispersed and mixed.

〔Example〕

Production Example 1 (Production of disproportionated rosin glycidyl ester) Disproportionated rosin (acid value 162, softened 79%), 200 g of epichlorohydrin, and 0.1 g of benzyltrimethylammonium chloride were added, and the mixture was reacted at 60° C. for 4 hours. Then, at the same temperature, 16 g of granular sodium hydroxide was added in portions,
The temperature was raised to 0°C, and the reaction was further carried out for 2 hours. After filtering the precipitated salt, unreacted epichlorohydrin was distilled off from the filtrate using a rotary evaporator, and further heated to 2 mmHg.
The volatile components were completely removed under conditions of 120° C. to obtain the title pale yellow oil (yield 97.2%).

Disproportionated rosin glycidyl ester 450 parts Phthalic anhydride 250 parts Triethylene glycol 90 parts N2
The reaction was observed for 4 hours at 240°C under zero ambient atmosphere. Further, 5 parts of trimellitic anhydride was added, and the reaction was continued until a predetermined molecular weight was reached to obtain a resin.

After reacting 450 parts of disproportionated rosin glycidyl ester at 180°C for 2 hours with 450 parts of bisphenol Al2O, 1 part of dodecenyl succinic anhydride was added.
35 parts were added thereto, and the mixture was reacted at 240° C. for 3 hours.Furthermore, a part of fumarized rosin triglycidyl ester 2015 was added thereto, and the reaction continued to obtain a resin.

Example 1 Resin of Production Example 1 70 parts by weight P
30 parts by weight of r1ntex (carbon black manufactured by Degussa) was kneaded with two rolls and then ground.

50 parts by weight of the pulverized product 200 parts by weight of Isopar H (EXXSON) were placed in a ball mill and dispersed for 24 hours, and then 300 parts by weight of Isopar H was added.
Parts by weight were added and dispersed for 1 hour to obtain a concentrated toner.

200 g of this was diluted with Isopar HIQ and used as a developer.

Example 2 Resin of Production Example 2 57 parts by weight 250p
(Sanyo Chemical Polyethylene) 8 parts by weight MA60 (
Add 35 parts by weight of Mitsubishi Kasei Carbon Black to the flasher.
After mixing, it was crushed.

The pulverized product 60 parts by weight stearyl methacrylate/methyl metaisopar H (E
XXSON Co., Ltd.) 100 parts by weight or less The same procedure as in Example 1 was carried out.

Example 3 Resin of Production Example 3 60 parts by weight AC40
0A (Allied Chemical Company) 10 parts by weight Regal 40
30 parts by weight of 0 (Cabot) was cross-pulverized using a flasher. The same procedure as in Example 1 was carried out below.

Comparative Example In Example 1, 0A1i1A was used instead of the resin of Production Example 1.
X is used as is.

After producing an image using a Ricoh CT5085 with the fixing heater turned off, non-offset areas were examined using a fixing tester. The results are shown in the table below.

As is clear from the above results, according to the present invention, it is possible to obtain a wide range of temperatures in which hot roller fixing is possible without an offset phenomenon, and it is understood that hot roller fixing is possible.

〔effect〕

The developer of the present invention enables hot roller fixing without causing an offset phenomenon, and facilitates high-speed fixing.

Furthermore, the liquid developer of the present invention can be used to fix images with high sharpness without bleeding or the like even by a flash fixing method.

Claims (1)

[Claims] 1. In an electrostatographic liquid developer comprising toner particles dispersed in a carrier liquid containing an aliphatic hydrocarbon as a main component, (
From the group consisting of I) rosin glycidyl ester, (II) dicarboxylic acid or dicarboxylic acid anhydride, (III) polyfunctional epoxy compound, trivalent or higher polybasic acid or its acid anhydride, and trivalent or higher polyhydric alcohol The product obtained by reacting at least one selected crosslinking agent and (IV) dihydric alcohol has a softening point of 50 to 190°C, a glass transition point of 10 to 170°C, and a molecular weight of 2000 to 40000.
A liquid developer for electrostatic photography, characterized by containing a rosin-based polymer compound.