JP2000089501A - Toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a toner excellent in hot preservation resistance, low temperature fixability and anti-offsetting property even in continuous printing by a nonmagnetic one-component developing system by incorporating a specified amount of a specified hydrogenated resin. SOLUTION: The toner contains a hydrogenated resin obtained by copolymerizing dicyclopentadiene with styrene or its derivative. The hydrogenation rate of the hydrogenated resin is >=80%, preferably 90-95% and is confirmed by the bromine values of the petroleum resin before and after hydrogenation, The content of the hydrogenated resin in the toner is >=0.05 wt.%, preferably >=1 wt.% from the viewpoint of low temperature fixability and <=3 wt.% from the viewpoint of the toughness of the toner. The toner does not cause heat fusion to an electrifying blade, a developing roll, etc., even in continuous printing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner and a developing device used for developing an electrostatic latent image formed in electrophotography, electrostatic recording, electrostatic printing, and the like.

[0002]

2. Description of the Related Art Toners used in developing devices of the heat and pressure fixing type are required to be excellent in heat-resistant storage stability, low-temperature fixability and offset resistance.

In order to satisfy these requirements, a toner containing a binder resin and an aliphatic petroleum resin has been proposed (Japanese Patent Application Laid-Open No. 7-199534), but the heat-resistant storage stability is not sufficient. A toner composition comprising a styrene / butadiene resin and an aromatic petroleum resin having 7 to 10 carbon atoms (Japanese Patent Application Laid-Open No. Hei 4-257868) has also been proposed, but also there is almost no effect of improving the offset resistance. .

Further, in the non-magnetic one-component developing system, since the toner is frictionally charged when passing between the developing roll and the charging blade, it is desired that the toner to be used is hard to be thermally fused. No one satisfying all of these performances has been found.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to provide a non-magnetic one-component developing system which can be continuously printed without being heat-fused to a charging blade and a developing roll. It is an object of the present invention to provide a toner and a developing device excellent in both properties.

[0006]

The gist of the present invention is to provide a toner containing a binder resin and a colorant, wherein dicyclopentadiene and styrene or a styrene derivative are copolymerized and hydrogenated by 80% or more. Hydrogenated resin
The present invention relates to a toner containing 5 to 3% by weight and a non-magnetic one-component developing system using the toner.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A major feature of the toner of the present invention is that
It is intended to contain a hydrogenated resin obtained by copolymerizing dicyclopentadiene and styrene or a styrene derivative and hydrogenating the copolymer by 80% or more. The toner containing the hydrogenated resin does not cause thermal fusion to the charging blade, the developing roll, etc. even during continuous printing, and has excellent heat resistance storage stability, low-temperature fixability and offset resistance. Become.

In the present invention, examples of the styrene derivative include α-methylstyrene, β-methylstyrene, toluene, vinyltoluene, and isopropenylbenzene.

The hydrogenated resin is disclosed in, for example, Japanese Patent No. 2762.
209 and Japanese Patent Publication No. 5-87085.

The hydrogenation rate of the hydrogenated resin is 80% or more, preferably 90% or more, and preferably 95% or less, and is obtained from the bromine values of the petroleum resin before hydrogenation and the petroleum resin after hydrogenation. Can be The bromine value is measured by a method according to JIS-2605.

As the hydrogenated resin, for example, "Imarv P-90" [hydrogenation rate: 100%, softening point: 90]
° C, melt viscosity (at 160 ° C, the same applies hereinafter): 390
mPa · s], “Imarb P-100” [hydrogenation rate: 100%, softening point: 100 ° C., melt viscosity: 1000]
mPa · s], “Imarb P-115” [hydrogenation rate: 100%, softening point: 115 ° C., melt viscosity: 4250]
mPa · s], “I-MARV P-125” [hydrogenation rate: 100%, softening point: 125 ° C., melt viscosity: 1080
0 mPa · s], “I-MARV P-140” [hydrogenation rate: 100%, softening point: 140 ° C., melt viscosity: 3925]
0 mPa · s], “I-MARV S-100” [hydrogenation rate: 90%, softening point: 100 ° C., melt viscosity: 1160 m
Pa · s], “I-Marve S-110” [hydrogenation rate:
90%, softening point: 110 ° C., melt viscosity: 1830 mPa
.S], “I-MARV S-125” [hydrogenation rate: 90
%, Softening point: 125 ° C., melt viscosity: 13,700 mPa ·
s], "Imarb S-140" [hydrogenation rate: 90
%, Softening point: 140 ° C., melt viscosity: 27000 mPa ·
s] (above, manufactured by Idemitsu Petrochemical Co., Ltd.).

The softening point of the hydrogenated resin is preferably 95 ° C. or higher, more preferably 100 ° C. or higher, from the viewpoint of heat-resistant storage stability of the toner, and is preferably 1 from the viewpoint of low-temperature fixability.
30 ° C. or less.

The melt viscosity of the hydrogenated resin at 160 ° C. is preferably 500 mP from the viewpoint of offset resistance.
a · s or more, more preferably 1000 mPa · s or more,
From the viewpoint of low-temperature fixability, preferably 30,000 mPa ·
s or less, more preferably 15000 mPa · s or less, particularly preferably 10,000 mPa · s or less.

The content of the hydrogenated resin in the toner is 0.05% by weight or more, preferably 1% by weight or more from the viewpoint of low-temperature fixability, and 3% by weight or less from the viewpoint of toner toughness.

As the binder resin used in the toner of the present invention, a resin generally used for a toner is used, for example, polyester, polyamide, acrylic resin, epoxy resin, polycarbonate, polyurethane, silicone resin, fluorine resin. And natural and synthetic waxes. Of these, polyesters are preferred from the viewpoint of achieving both the fixing property and the durability of the toner. Such a polyester is desirably contained in the binder resin in an amount of 70% by weight or more, preferably 90 to 100% by weight.

The raw material monomer of the polyester is not particularly limited, and a known polyhydric alcohol component and a polycarboxylic acid component such as carboxylic acid, carboxylic anhydride, and carboxylic acid ester are used.

Examples of the polyhydric alcohol component include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene (2) -2,2-bis (4-hydroxy Alkylene oxide (addition mole number: 1 to 10) of bisphenol A such as phenyl) propane, ethylene glycol, propylene glycol, glycerin, pentaerythritol, trimethylolpropane, hydrogenated bisphenol A, sorbitol, or an etherified polyhydroxyl thereof And compounds containing one or more of these. Further, from the viewpoint of improving the durability of the toner, it is preferable that the alkylene oxide adduct of bisphenol A is used in an amount of 5 mol% or more in the alcohol component.

Examples of the polyvalent carboxylic acid component include dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, fumaric acid, and maleic acid, and alkyl groups having 1 to 20 carbon atoms such as dodecenylsuccinic acid and octylsuccinic acid. Or succinic acid, trimellitic acid, pyromellitic acid, anhydrides of these acids, and alkyl (C1-8) esters of those acids, which are substituted with an alkenyl group having 2 to 20 carbon atoms. Those containing at least one of the following are preferred.

The polyester is produced by condensation polymerization of a polyhydric alcohol component and a polycarboxylic acid component in an inert gas atmosphere, if necessary, using an esterification catalyst at a temperature of 180 to 250 ° C. can do.

The acid value of the polyester is preferably 50 (KOH mg / g) or less from the viewpoint of environmental stability. In the present invention, the acid value of the polyester is adjusted by adjusting the reaction conditions and the ratio of the raw material alcohol and carboxylic acid,
Or by using the corresponding ester as the acid component,
It can be controlled within the above range.

The glass transition point of the polyester is 55 to 80.
° C and a softening point are preferably 80 to 150 ° C.

The colorant is not particularly limited, and dyes and pigments conventionally used as colorants for black toners or color toners can be used. Examples thereof include carbon black, phthalocyanine blue, and permanent brown FG. , Brilliant First Scarlet, Pigment Green B, Rhodamine-B base, Solvent Red 49, Solvent Red 146, Solvent Blue 35,
Quinacridone, carmine 6B, disazo yellow and the like. The content of the colorant is preferably 2 to 25 parts by weight based on 100 parts by weight of the binder resin.

The toner of the present invention can be produced by a conventionally known method such as a kneading and pulverizing method, a spray drying method, and a polymerization method. For example, after uniformly mixing a binder resin, a colorant, a hydrogenated resin, and the like with a mixer such as a ball mill, melt kneading with a closed kneader or a single or twin screw kneading extruder, cooling, pulverizing, and classifying. Method. The weight average particle diameter of the toner of the present invention is 3 to 20 μm.
It is preferred that it is about.

The toner of the present invention further comprises a charge control agent,
Ferrite and other magnetic materials, conductivity modifiers, tin oxide, silica, alumina, zirconia, titania, cerium oxide,
Additives such as metal oxides such as zinc oxide, extenders, reinforcing fillers such as fibrous substances, antioxidants, antioxidants, release agents, fluidity improvers, and cleanability improvers are appropriately added. May be.

The toner of the present invention may be used alone as a developer when it contains a magnetic fine powder, or as a non-magnetic one-component developer when it does not contain a magnetic fine powder, or may be mixed with a carrier. Although it is used as a two-component developer, it is preferable to use it as a non-magnetic one-component developer from the viewpoint of simplicity and miniaturization of the apparatus because the toner is less likely to be thermally fused to a developing roll or the like.

Further, the present invention also provides a non-magnetic one-component developing type developing device using the toner of the present invention. Examples of the developing device of the present invention include a device in which the toner of the present invention is contained in a toner developing tank and the toner is charged by a carrier for conveyance and a pressure contact member contributing to charging.

[0027]

[Example] [Glass transition point] Differential scanning calorimeter "DSC2"
10 "(manufactured by Seiko Denshi Kogyo KK) at a heating rate of 10 ° C / min. [Acid value] It is measured according to a method according to JIS K0070. [Softening point] It is measured according to a method in accordance with JIS K2207. [Melt viscosity] Koka type flow tester "CFT-500
A "(manufactured by Shimadzu Corporation) is used to plot the viscosity curve, and the value at 160 ° C is determined.

Example of Resin Production Polyoxypropylene (2.2) -2,2-bis (4-
2630 g of hydroxyphenyl) propane, 1050 g of polyoxyethylene (2) -2,2-bis (4-hydroxyphenyl) propane, 970 g of terephthalic acid, 335 g of isododecenyl succinic anhydride, 31 trimellitic acid
0 g and dibutyltin oxide 13 g under nitrogen atmosphere.
The reaction was continued while stirring at 30 ° C until the softening point measured according to ASTM E28-67 reached 149 ° C.
The obtained resin is referred to as polyester A. Polyester A
Had a glass transition point of 62 ° C. and an acid value of 6 KOH mg / g.

Example 1 91 parts by weight of polyester A Charge control agent "Bontron N-04" (manufactured by Orient Chemical Industries) 3 parts by weight Carbon black "REGAL-330R" (manufactured by Cabot) 4 parts by weight Hydrogenated resin "Imarb" S-100 ”1 part by weight Polypropylene wax 1 part by weight“ NP-055 ”(manufactured by Mitsui Petrochemical Industry Co., Ltd.) After kneading the above composition with a biaxial kneader heated to 110 ° C., cut a 2 mm mesh with a mechanical grinder. The powder was roughly pulverized to such an extent that the powder passed, and a powder having a weight average particle diameter of 9.5 μm was obtained using a wind-type pulverizer / classifier. Then, the obtained powder 10
0 parts by weight and 0.5 parts by weight of hydrophobic silica “HVK-2150” (manufactured by Wacker Inc.) were mixed using a high-speed stirrer to obtain a toner.

Example 2 A toner was obtained in the same manner as in Example 1 except that the amount of the polyester A used was 89 parts by weight and the amount of the “Imarb S-100” was 3 parts by weight.

Example 3 Instead of "Imarb S-100", "Imarb P-
A toner was obtained in the same manner as in Example 1, except that 1 part by weight of "90" was used.

Example 4 Instead of "I-MARve S-100", "I-MARVE S-100" was used.
A toner was obtained in the same manner as in Example 1 except that 1 part by weight of No. 140 was used.

Example 5 Instead of polyester A, 91 parts by weight of styrene acrylic resin "Hymer TB-1000F" (manufactured by Sanyo Chemical Industries, glass transition point: 60 ° C, number average molecular weight: about 12,000, weight average molecular weight: 270,000) A toner was obtained in the same manner as in Example 1 except for using.

Comparative Example 1 A toner was obtained in the same manner as in Example 1 except that the amount of polyester A was changed to 88 parts by weight and the amount of “Imarb S-100” was changed to 4 parts by weight.

Comparative Example 2 A toner was obtained in the same manner as in Example 1 except that the amount of the polyester A was changed to 92 parts by weight without using "Imarve S-100".

COMPARATIVE EXAMPLE 3 A styrene acrylic resin "Hymer TB-1" was used instead of polyester A without "Imarve S-100".
000F "(manufactured by Sanyo Chemical Industries, glass transition point: 60 ° C, number average molecular weight: about 12,000, weight average molecular weight: 270,000)
A toner was obtained in the same manner as in Example 1, except that 92 parts by weight was used.

Test Example 1 Using the toners obtained in Examples 1 to 5 and Comparative Examples 1 to 3,
Using a page printer "HL-730" (manufactured by Brother Industries, Ltd.) which is a reversal developing device of a non-magnetic one-component developing system, 20,000 sheets of printing at a printing rate of 4% are intermittently printed, and the toner durability and The heat storage stability was evaluated. Table 1 shows the results.

[Durability] The image quality after the intermittent printing of 20,000 sheets and the degree of fusion of the toner to the photosensitive member, the developing roll and the charging blade are visually judged, and comprehensively evaluated according to the following evaluation criteria.

[Evaluation Criteria] A: Particularly good B: Good x: Not practical

[Heat-resistant storage stability] The cohesion of the toner after intermittent printing of 20,000 sheets is visually determined, and evaluated according to the following evaluation criteria.

[Evaluation Criteria] な し: No aggregation や: Slightly aggregated, but actually usable ×: Aggregated, not practical

Test Example 2 The page printer “HL-730” used in Test Example 1 was modified, and the toners of Examples 1 to 5 and Comparative Examples 1 to 3 were fixed at different fixing temperatures, and the low-temperature fixability of the toner was changed. And the offset resistance was evaluated. Table 1 shows the results.

[Low-temperature fixability] The minimum fixing temperature of the toner is measured and evaluated according to the following evaluation criteria.

[Evaluation Criteria] A: The fixing temperature is so low that the rise in the temperature inside the machine is not noticeable. A: It can be actually used in consideration of the rise in the temperature inside the machine.

[Offset Resistance] The non-offset area of the toner is measured and evaluated according to the following evaluation criteria.

[Evaluation Criteria] A: The non-offset region is very wide and there is no problem in actual use.

[0047]

[Table 1]

From the above results, it can be seen that the toners of Examples 1 to 5 are all excellent in durability, heat-resistant storage stability, low-temperature fixability and offset resistance. On the other hand, the toners of Comparative Examples 1 to 3 have problems in any of durability, heat-resistant storage stability, low-temperature fixability and anti-offset properties, and have a problem in practical use.

[0049]

According to the present invention, even when continuous printing is performed by a developing method employing a non-magnetic one-component developing method, the toner is not heat-fused to the charging blade and the developing roll over time, and the heat-resistant storage stability is maintained. Thus, it has become possible to provide a toner and a developing device which are excellent in both low-temperature fixability and offset resistance.

Claims (5)

[Claims] 1. A toner containing a binder resin and a colorant, wherein a hydrogenated resin obtained by copolymerizing dicyclopentadiene and styrene or a styrene derivative and hydrogenating at least 80% is used in an amount of from 0.05 to 0.05%. A toner containing 3% by weight. 2. The softening point of the hydrogenated resin is 95 to 130 ° C.
The toner according to claim 1, wherein 3. The toner according to claim 1, wherein the melt viscosity of the hydrogenated resin at 160 ° C. is 30,000 mPa · s or less. 4. The binder resin according to claim 1, wherein the binder resin is polyester.
4. The toner according to any one of claims 1 to 3. 5. A developing device of a non-magnetic one-component developing system using the toner according to claim 1.