JPS6375755A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To reduce thermal decomposability and volatility and to obtain supe rior flash fixability by using the binder resin of a toner composed essentially of a polyester having specified components and incorporating >=3wt.% carbon black and specifying the melt viscosity of the toner. CONSTITUTION:The resin of the toner is composed essentially of the polyester containing terephthalic acid and/or isophthalic acid as a main carboxylic acid component and neopentyl glycol as a main alcohol component. The carbon black is incorporated in the toner in an amount of >=3wt.% of the whole toner, and the melt viscosity of the toner at 140 deg.C is controlled in the range of 3,000-6,000 P, thus permitting thermal decomposability and volatility to be lowered and fixability to be enhanced by using such a toner for light flash fixing.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a toner for developing electrostatic images used in printers, facsimile machines, copying machines, etc. employing electrophotography, electrostatic recording methods, and the like. More specifically, the present invention relates to a toner for developing electrostatic images suitable for a light flash deposition method in this field.

(Prior Art) The main fixing methods for electrostatic image developing toner (hereinafter referred to as toner) used in printers, facsimile machines, copying machines, etc. that employ electrophotography, electrostatic recording methods, etc. include pressure method, There are heat pressure method and optical flash irradiation method.

Fixing by light flash irradiation is a method in which a light flash obtained from a xenon lamp or the like is applied to the toner on the recording paper to fuse the toner to the recording paper.

Compared to other methods, do not choose the type of recording paper (thin to thick paper, laminated paper, preprinted paper, etc.).

It has features such as being able to be used as soon as the power is turned on, and being a non-contact fixing method that provides high-quality printing.

Conventionally, the toner used is JP-A-56-3.
Examples include styrene/acrylic resin toners disclosed in Japanese Patent Laid-open No. 0139, etc., and epoxy resin toners disclosed in Japanese Patent Application Laid-open No. 57-96354.

(Problems to be Solved by the Invention) In the fixing method using the optical flash irradiation method, the toner is instantly heated to a high temperature, so the conventional toner described above generates a large amount of decomposed products and pollutes the work environment. In addition, voids frequently occur in the fixed toner, and the recording paper cannot be sufficiently hidden, resulting in low print density.

The present invention has low thermal decomposition properties during optical flash fixing.

The purpose of the present invention is to provide a toner that has low volatility and provides excellent fixing properties.

(Means for Solving the Problems) The present invention includes a polyester resin having terephthalic acid and/or isophthalic acid as a carboxylic acid component and neopentyl glycol as an alcohol component as a main component, and a carbon blank. Contains more than 3 layers of toner, 14 of toner
The present invention relates to a toner for developing electrostatic images having a melt viscosity at 0° C. of about 0 to 6.100 poise.

The carboxylic acid component of the polyester resin of the present invention must contain terephthalic acid and/or isophthalic acid as a main component in order to improve the thermal decomposition resistance of the toner. For example, malonic acid, co-phosphoric acid, glutaric acid, adipic acid, azelaic acid, and sebacic acid within a range that does not impair the heat decomposition resistance of the toner.

Dimer acid, maleic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, endomethylenetetrahydrophthalic acid, endomethylenehexahydrophthalic acid, naphthalene dicarboxylic acid, diphenolic acid, Mellitic acid, pyromellitic acid.

trimesic acid, cyclopentanedicarboxylic acid, 3゜i
4.4'-benzophenonetetracarboxyll, 1.
To λ4. -butanetetracarboxylic acid, 42'-bis-(
4-carboxyphenyl)propane, diimidocarboxylic acid obtained from trimellitic anhydride and 4,4'-diaminophenylmethane, tris-(β-carboxyethyl)in cyanurate, inocyanurate ring-containing polyisocyanurate and Incyanurate ring-containing polyimide polycarboxylic acid obtained from mellitic anhydride (2) For example, incyanurate ring-containing polyimide polycarboxylic acid obtained from trimerization reactant of tolylene diisocyanate, xylylene/diisocyanate or hysophorone diisocyanate and trimellitic anhydride One type or two or more types of carboxylic acids can also be used in combination. These carboxylic acid components are desirably used together in an amount of about 12 mol or less based on the total carboxylic acid components.

The alcohol component of the polyester resin of the present invention is:

In order to improve the thermal decomposition resistance of the toner, it is necessary to use neopentyl glycol as the main component.

In addition, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, cyfuropylene glycol, impentyl glycol, hydrogenated bisphenol A, 1,3-butane may be used within a range that does not impair the thermal decomposition resistance of the toner. Diol, 1,4-butanediol, 1,6-hexanediol, xylylene glycol, 1,4-7 chlorohexanedimethanol, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol.

Bis-(β-hydroxyethyl) terephthalate.

Tris-(β-hydroxyethyl)in cyanurate,
2,2.4-1-limethylbentane-1,3-diol, a reaction product of bisphenol A and ethylene oxide or propylene oxide may be used alone or in combination of two or more. These alcohol components are desirably used together in an amount of about 30 mol or less based on the total alcohol components.

The melt viscosity at 140°C of the polyester resin of the present invention is 2. The melt viscosity at 140°C of the toner according to the present invention is 3,000 to
2.80 to be within the range of 6,100poise
It is desirable to set it in the range of 0 to 5.800 poise.

The polyester resin is produced by condensation polymerization of the above-mentioned components according to a conventional method, but the carboxylic acid component used may be an ester-forming derivative. When a free carboxylic acid compound is used, the esterification catalyst 9 should be used in an amount of I x 10'' to 10'' based on the total raw material components, such as an organic metal such as dibutyltin dilaurate or dibutyltin oxide.
1% by weight.

In addition, when the carboxylic acid component used is a lower alkyl ester, transesterification catalyst 1, such as metal acetates such as lead acetate, zinc acetate, and magnesium acetate, and metal oxides such as zinc oxide and antimony oxide, is added to all raw material components. te5
10-' to 5 X 10-2% by weight can be added to accelerate the reaction.

The toner according to the present invention needs to contain carbon black in an amount of 3tt% or more, preferably 4tt% or more, based on the total toner. If the amount of carbon blank blended is less than 3% by weight, the optical Franche fixing properties will be poor. Further, the blending amount of the carbon blank is preferably 20% by weight or less based on the entire toner. If it exceeds 20% by weight, it tends to become difficult to function as a toner. Furthermore, it is particularly desirable that the toner according to the present invention contains a carbon blank in an amount of 15% by weight or less based on the entire toner. This constraint is 1
Not necessary to achieve the objectives of the invention.

If carbon blank is added in an amount exceeding 15% by weight based on the total toner, the triboelectric charging properties of the toner may decrease during repeated use, resulting in deterioration of image quality, but this is necessary to avoid such problems. be. Therefore, in some cases, carbon black may be added to the entire toner.
It is also possible to use more than 5% by weight. Note that 9 in the present invention.

Carbon blank mainly has the function of converting light energy into thermal energy and the function of a coloring agent.

The carbon blank that can be used in the present invention is 2, for example, Mitsubishi carbon blank ÷ 600. MCF-88,
MA-600, MA-100, MA-8, MA-11,
30. φ32. 33. 40. ÷44. 45° 50. φ52. ◆55 (all manufactured by Mitsubishi Chemical Corporation).

Lapen 410, 420, 430, 450, 500°8
25.890, 1000.1020, 1030, 103
5゜1040.1085,1170,1200,125
0°1255.1500,1800,2000,210
0°3500.5250,5750,7000,800
Examples include, but are not limited to, 0°5ooo, Neo Spectra Mark IV, AG, Mark 1, Mark ■, Royal Spectra lt, Columbian Carbon Nipponbare) ft.

The toner according to the present invention can contain other resins and additives as necessary.

Other resins include styrene resin, styrene-acrylic resin, silicone resin, polyester carbonate resin, xylene resin, epoxy resin, phenol resin, diene resin, phenol resin, coumaron resin, adenoid resin, amino resin, urethane resin, etc. These are desirably blended in an amount within 20% by weight of the total toner components.

Additives include nigrosine dyes, basic nigrosine dyes, fatty acid-modified nigrosine dyes, metal complexes of azo dyes, chromium complexes of salicylic acid spinners, hydrophobic silica powder, metal salts of saturated or unsaturated fatty acids, polyolefins, and alkyl esters of fatty acids. These include fatty acid amides, conductive substances, etc., and it is desirable to blend these in an amount of 5% by weight or less in the total toner components. In addition, for these picture machining operations, except for flesh machining, the toner material must be removed [! It can be mixed evenly.

The toner according to the present invention can also be made into a magnetic toner by blending a magnetic material such as magnetite at about 30 to 60% by weight based on the total toner.

The toner according to the present invention has a melt viscosity of 3.000 at 140°C.
It needs to be in the range of ~6,000 poise. 14
If the melt viscosity at 0° C. is less than 3.000 poise, the object of the present invention cannot be achieved because the volatile content of the toner increases during optical flash fixation, and the storage stability of the toner also becomes poor. on the other hand.

If the melt viscosity at 140° C. exceeds 6.100 poise, the optical flash fixing properties of the toner will be poor, making it impossible to achieve the object of the present invention. Note that 9 the melt viscosity of the present invention is
Shimadzu flow tester CFT-500 type (■Shimadzu Corporation!A
) at a constant temperature of 140° C. under the conditions of a pressure of 10 kgf/cm”, a temperature increase rate of 6° C./min, and a die size of 0.5 mmφX1on.

(Example) The invention will be explained in the following examples.

(1) Production of polyester resin A carboxylic acid component, an alcohol component, and a catalyst were placed in a reactor and reacted under a nitrogen stream at a temperature of 180 to 230°C until a predetermined acid value was reached. Table 1 summarizes the monomer formulation and typical physical properties of the synthesized polyester resin.

(2) Production of toner The compositions shown in Table 2 were first dry mixed and then melt-kneaded using an extruder equipped with a die (temperature of the kneaded material immediately after extrusion was 130 to 140°C). Table 2 also shows the melt viscosity of the toner thus produced.

Dry type copying machine SELEX 1200 (Copia■$
1, reversal development was performed to obtain an unfixed toner image carried on 9 sheets of paper. The unfixed toner image at a distance of approximately 67 # is then exposed to a light flash from a xenon lamp (approximately 5
00 J/pulse). The fixability of this fixed toner image was calculated using the following formula (Table 2).

Here, Do: Reflection density of fixed toner image D=Reflection density after peeling off the fixed toner image from the tape Also, the amount of white smoke emitted from the toner image during fixing was visually observed (Table 2). Separately, the amount of weight loss of the toner by TGA method was measured according to the following method. The thermobalance
Measurement was performed using rmof Iex (manufactured by Rigaku Denki) at a temperature increase rate of 300°C/min in an air atmosphere.
The amount of weight loss was read when the temperature was raised to 0°C.

(Effects of the Invention) The electrostatic image developing toner of the present invention has low thermal decomposition when fixed by a flash fixing method.

It has low volatility and exhibits excellent fixing properties.

Claims (1)

[Claims] 1. A toner containing as a main resin component a polyester resin having terephthalic acid and/or isophthalic acid as a carboxylic acid component and neopentyl glycol as an alcohol component, and containing carbon black in an amount of 3% by weight or more based on the entire toner. A toner for developing electrostatic images having a melt viscosity of 3,000 to 6,100 poise at 140°C.