JPS59177570A - Toner for powder developer - Google Patents

Abstract

PURPOSE:To prevent sticking and adhesion of toner resin onto the carrier and the surface of a photosensitive plate by using the resulted poroduct of reaction of an epoxy compd. contg. an epoxy group in a molecule and a PE or PP modified with a carboxylic acid at the terminal as base resin for a toner. CONSTITUTION:A toner contains a base resin consisting of the resulted product of reaction of an epoxy compd. contg. at least >=1 epoxy group in a molecule and a PE or PP modified with a carboxylic acid at the terminal and a coloring agent. The epoxy compd. may be any of arom. and aliphat. epoxy resins; for example, said compd. is enumerated by an epoxy resin obtainable from bisphenol A and epichlorohydrin, a novolak type epoxy resin obtainable from a novolak type phenol resin and epichlorohydrin, etc. The PE modified with a carboxylic acid at the terminal is the PE of which the terminal hydrogen atom of a PE homopolymer having no functional group is modified by a carboxylic group -COOH and of which the average mol.wt. is preferable in a range of 1,000- 10,000 and the acid value in a range of 3-30. The toner is produced by using a kneader or the like, adding a coloring agent to the epoxy compd., and the PE or PP modified with a carboxylic acid at the terminal and kneading the mixture.

Description

[Detailed description of the invention] (1) Technical field of one invention The present invention relates to an electrophotographic toner.

(2) Background of the technology When powder development is performed in an electrophotographic printer, facsimile/millimeter, or copier, the developer is a mixture of colored resin powder called toner and iron powder or glass powder called carrier. used. Toners are generally prepared by dispersing a coloring agent such as carbon black in a binder resin and then pulverized, and as the binder resin, a low polymer polymer generally called an oligomer is often used. Oligomers have low molecular weights, low melting temperatures, and good thermal stability, so they are widely used as binder resins for electrophotographic toners.

(3) Prior Art and Problems However, with the recent demand for increased copying speeds, the developer consisting of toner and carrier is agitated at high speed, resulting in mutual friction and collision. A phenomenon in which toner sticks to the surface of the carrier (toner filming) occurs, and as this progresses, the surface of the carrier is completely covered with a film of toner, and such carrier is mixed with other toners and agitated. Another problem is that toner adheres to the surface of the photosensitive plate, which causes changes in printing pressure and fog. As a method to prevent toner filming, it has been considered from the carrier side to coat the carrier surface Ini with a resin that is non-adhesive to a specific toner resin. There is also a strong demand for toner to take measures including:

(4) 9 Purpose of the Invention The purpose of the present invention is to prevent such adhesion and adhesion of toner resin to the carrier and photosensitive plate surface, and to improve the toner resin.

(5) 1 Structure of the Invention The composition of the present invention uses a reaction product of an epoxy compound containing at least one epoxy group in the molecule and a terminal carboxylic acid-modified polyethylene or a terminal carboxylic acid-modified polypropylene as a toner base resin. It is characterized by the use of

Conventionally, when Ehokin alkaline fat alone was used as an adhesive resin, a prepolymer with a relatively low molecular weight had to be used so that it could be melted and fixed with as little thermal energy as possible, and toner filming was likely to occur. Therefore, the present inventors reacted such a relatively low molecular weight epoxy prepolymer with polyethylene or polypropylene, which has a melting point in the low temperature range but exhibits non-adhesion to metals even in the softening temperature range. We have discovered that it is possible to prevent toner filming from degrading fixing performance.

Since the polyethylene used in the present invention is modified with a carboxylic acid at the terminal end, it reacts with the epoxy resin during kneading, so that it can be simply mixed with an epoxy resin using a polyethylene homopolymer or polypropylene homopolymer with completely different functional groups. It is characterized by the fact that bleed-out, which occurs when mixing, does not occur.

The epoxy compounds used in the present invention include aromatic,
Any aliphatic epoxy resin may be used, such as epoxy resin obtained from bisphenol A and epichlorohydrin, novolac-type epoxy resin obtained from novolac-type phenol 411 fat and epichlorohydrin, epoxy resin obtained from phthalic acid and epichlorohydrin, toluidine, aniline, etc. Examples include epoxy resins obtained from aromatic amines and epichlorohydrin.

In addition, the terminal carboxylic acid-modified polyethylene used in the present invention is a polyethylene homopolymer without functional groups whose terminal hydrogen atoms are modified with carboxyl & COOH, and has an average molecular weight of 1,000 to 10,000 and an acid value of 3 to 3. Anything in the range of 30 is preferable.

In addition, the terminal carboxylic acid-modified polypropylene used in the present invention is a functional group-free polypropy V nopomo polymer whose terminal end is modified with a carboxyl group (-COOH) K, and has an average molecular weight of 1,000 to 20,000 and an acid value of 3. Preferably, the number is in the range of 30 to 30.

Specific examples of epoxy resins that can be used in the present invention include 1 Epikote 11001, 1004°1007 manufactured by Neru Co., Ltd.
and 1009. 1 Araldite J from Ciba Kaigy
6071, 7071, 7072, 6084, 7097
．． 6097 and 6099. Dow rDERJ 66
0,661,662°664, 667, 668 and 669. and Inu H Hon Ink Co., Ltd.'s [Ebikloa J
1050, 3050, 4050 and 7050.

The toner of the present invention is prepared by adding a color sacrificial agent to an epoxy compound, a terminal carbo/acid-modified polyethylene or a terminal carboxylic acid-modified polypropylene and kneading them using a kneader or the like in a conventional manner. The desired toner is obtained by crushing and classifying the resulting I.car mass.

(6) Example of 1 invention The present invention will be explained below with reference to Examples.

(Example 1) Epoxy resin (trade name [Epicron 4050J Inu Hon Ink Kagaku Kogyo Co., Ltd.] 83 weights 1 part, terminal carboxylic acid-modified poly”-chire/(trade name “Zanwanox E-3001 made by Mitsui Kasei Kogyo Co., Ltd.) 101 Carbon black (R())
5 parts by weight of product name 1 Buranoku Pearls L] manufactured by Cavonoto Co., Ltd., and 2 parts by weight of dye (product name 1 1.
Kneaded for 4 minutes, then pulverized with a dienotoharpilizer, classified with a wind divider, and then obtained toner A/
child.

(Comparative Example 1) The same manufacturing process as in Example 15 was carried out without using the terminal carboxylic acid-modified polyethylene, but with the composition of 93 parts by weight of Evokin resin, 5 parts by weight of carbon blank, and 2 parts by weight of dye. V Litker B was produced.

(6) Example of 1 invention The present invention will be explained below with reference to Examples.

Example Ephoxy resin (trade name: "Ebi Chrono 4050j, manufactured by Dainippon Ink and Chemicals Co., Ltd.) 78 m fa: parts, terminal carboxylic acid-modified polypropylene/(trade name: [Viscol TS-20
01 Manufactured by Sanyo Chemical Industries) 15 Oki, Okibe, Carphone Black (Product name: ``Branok Barz L4 Manufactured by Kabonoto Co., Ltd.'') 5 parts by weight, Dye (11) Product name: ``Nicron Base EXj Orie/To Chemical Co., Ltd.) 21 parts Rei ( [ft] for 60 minutes in a kneader heated to 100°C.

It is pulverized using a topalbinizer and classified using a wind classifier to produce Totsu-C.

(Comparative Example 2) A portion of the Epoquin resin 93 heavy Jd of the example and Carbo Black 5M are used.
Toner D was prepared by the same manufacturing process as in the example with the composition of the dye type 2 opening.

For these toners A to D, the carrier is TSV10.
Adjust the developer (toner concentration 3wt%) combined with 0/200 (made by B genuine iron powder) and use the F67L5D laser printer (
A filming test was carried out under the test conditions shown in Table 1 using a camera (manufactured by Fujitsu).

Development Reversal development using a magnetic brush Printing speed 2000 lines/min Photoresifter Se Drum initial voltage +550 ■ Fixing method Furanoshi fixed temperature condition 20-23°C Evaluation ■ Toner filming on carrier surface k
The arrow measurement method is as follows: 1. After removing toner particles electrostatically adhered to the carrier surface from the developer using a surfactant, drying and weighing the developer, the method is as follows: Methyl/1. After washing with ethyl ketone in the groove where the toner color comes out, dry it and weigh it again. This methyl ethyl ketone was determined as 7.

■■ Filming occurred on the drum during continuous vertical line printing, and the evaluation was based on the number of sheets printed when the filming image on the drum was offset from the paper.

The results are shown in Tables 2 and 3.

Toner A reacted with modified polyethylene has a smaller amount of toner filming on the carrier surface than Toner B.
Drum filming is 35,000 sheets and Toner B is 500 sheets.
This is a 7 times improvement compared to 0 sheets.

Table 2 Drum filming toner A on carrier surface 0.3% 350
00 sheets toner B O. 9%
5000 sheets □□ーーーー
7 →--d- Comparative Example 3 Same composition except that unmodified polyenalene homopolymer (trade name: I' Sunwax 151-Pj manufactured by Sanyo Chemical Industries, Ltd.) was used instead of the '&t4i polyethylene in the example. A prototype toner was produced using the following blending ratios. This toner at F6
When 715D was evaluated using the same test method as Toner A and Toner B, fogging occurred in the background area after 8,000 sheets were printed, and the print quality deteriorated significantly. This is thought to be due to polyethylene seeping out from the toner and bleed-out [7], and the formation of a polyethylene film on the first conductor drum, causing an abnormality in photo sensitivity.

Toner C reacted with modified polyglopylene has a smaller amount of toner filming on the carrier surface than Toner D, and drum filming was 30,000 sheets compared to 50 sheets of Toner B.
It is 6 times better than 00 sheets. Name [Biscole 6
60-PJ (manufactured by Sanyo Chemical Industries) was used, but the same composition was used,
A toner was prototyped with different mixing ratios.

This toner is toner A and toner B using F6715D.
A printing test was conducted under the same test conditions and evaluated as 10.
After printing 000 sheets, fogging occurred in the background and the printing quality deteriorated significantly. This is thought to be due to polypropylene seeping out from the toner (bleeding out) and forming a polypropylene film on the photoconodrum, resulting in abnormal photo sensitivity.

Claims (3)

[Claims] (1) Contains a reaction product of an Evogin compound containing at least one epoxy/group in one molecule and terminal carboxylic acid-modified polyethylene or terminal carboxylic acid-modified polypropylene as a base resin and a coloring agent. Toner for powder developer made of (2) Toner 0 according to claim 1, wherein the terminal carboxylic acid-modified polyethylene has an average molecular weight of 1,000 to 10,000. (3) Claim 1, wherein the terminal carboxylic acid-poor polypropylene has an average molecular weight of 1,000 to 20,000.
Toner described in section.