JPS5886557A - Pressure fixable toner - Google Patents

Abstract

PURPOSE:To enhance pressure fixability of a pressure-fixable toner, adhesion to a transfer material, pulverizability, etc., by adding as a binder component a composition of bisaliphatic acid amide and polyethylene wax in a specified weight ratio. CONSTITUTION:30-70pts.wt. bis (aliphatic acid amide), such as ethylene bisstearamide or hexabisoleamide is mixed with 70-30pts.wt. polyethylene wax preferably having 3,000-9,000 number average mol.wt., and the obtained composition is used for the main component of a binder, and when needed, a resin for blending, such as polypropylene, hydrogenated rosin ester, aliphatic cyclic hydrocarbon resin, or petroleum resin, is added. A colorant, such as carbon black, and a magnetic material, such as magnetite or ferrite, are added to this binder to obtain an intended pressure fixable toner.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to pressure fixable toners, and more particularly to improvements in binders used in pressure fixable toners.

In electrophotography, various toners have traditionally been used to develop electrostatic latent images, but these toners are used to convert electrostatic latent images into visible images and then transfer them onto transfer materials such as paper. Transferred and fixed by various methods. The fixing method varies depending on the toner used, but conventional toners do not provide satisfactory fixing performance.

For example, the heat roller fixing method has the disadvantages of taking a long time to fix, causing burnt copies, and consuming a lot of electricity, while the solvent fixing method uses organic solvents and is likely to cause pollution. .

The atmospheric fixing method has drawbacks such as high power consumption, a complicated fixing device, the possibility of copy burns, and, furthermore, the inability to perform high-speed fixing. Further, the flash fixing method has the same drawbacks as the above-mentioned atmospheric fixing method, and at the same time generates an odor due to toner decomposition gas.

Therefore, pressure fixing toners using a soft substance as a toner binder have been proposed in order to address the above-mentioned drawbacks, especially to improve the fixing properties. However, the pulverization property is poor and it becomes difficult to pulverize into fine particles when producing toner particles. In addition, pressure fixable toners are usually fixed using a pressure roller, but at this time, an offset phenomenon may occur to the pressure roller, and toner particles may fuse to the surface of the developing sleeve or photoreceptor. Easy to do. It also has the disadvantage of causing toner aggregation and caking during storage. A toner using polyethylene wax as a binder for the pressure-fixable dovetail is known, but although this toner has excellent plastic deformability, it is a main component of paper, which is most commonly used as a transfer material. , that is, it has poor adhesion to cellulose fibers. Further, products in which toner particles are encapsulated are also known, but they are expensive to manufacture and difficult to obtain toners with stable characteristics.

The present invention aims to solve the above-mentioned conventional drawbacks, and more specifically, by improving the binder of the toner, it improves the pressure fixability, the adhesion to the transfer member, and the crushability. An object of the present invention is to provide a pressure fixable toner having excellent properties such as properties.

Pressure fixing mainly involves entangling and adhering the fibers of the transfer member. Therefore, when considering pressure fixability, viscoelastic factors and adhesive factors are very important. Therefore, when we measured the creep characteristics of pressure fixing toners that are currently in practical use as a viscoelastic factor, we found that they can be approximated to a four-element model in a rheological theoretical model. Therefore, it is essential that the pressure fixable toner material has high plastic deformability.

Therefore, the present inventors investigated various resins with high plastic deformability as binders for pressure fixable toners, and found that low molecular weight polyethylene (also known as polyethylene wax) and oxidized polyethylene have excellent plastic deformability. It turned out that.

However, although these resins have excellent plastic deformability, they have problems in other properties. For example, low molecular weight polyethylene does not have sufficient adhesion to the transfer member, and oxidized polyethylene has poor crushability. Therefore, the present inventors further investigated and found that bis fatty acid amides 30 to 7
0 parts by weight polyethylene wax 30~10f! It has been found that the above-mentioned conventional drawbacks can be solved at once by using a composition consisting of a portion of the above as a binder component, and the present invention has been completed.

That is, the present invention is a pressure fixable toner characterized by containing a composition comprising 30 to 70 parts by weight of bis fatty acid amides and 30 to 70 parts by weight of polyethylene wax as a binder component.

In the present invention, since toner fixation is performed by pressure, the drawbacks that occur when using the pressure fixing method described above are completely solved, and the offset phenomenon and developing sleeve when conventional polyethylene is used as a binder are solved. , toner fusion to the photoreceptor is completely eliminated. Furthermore, since it has excellent pulverization properties, the toner can be pulverized extremely easily.

Examples of the bis fatty acid amide used in the pressure fixable toner of the present invention include methylene bis behenic acid amide, methylene bis stearic acid amide, methylene bis oleic acid amide, ethylene bis stearic acid amide, ethylene bis oleic acid amide, Examples include methylene bisstearamide, hexabisoleic acid amide, octamethylene biserucic acid amide, etc. Among these, ethylene bisstearic acid amide is particularly preferred. These bis fatty acid amides are used in combination with polyethylene wax in an amount of 30 to 70 parts by weight per 30 to 70 parts by weight of polyethylene wax. If the bis-fatty acid amide content is less than 30 parts by weight, the adhesion and crushability will not be sufficient (and if it exceeds 70 parts by weight, the plastic deformability will not be sufficient. In particular, if the bis fatty acid amide content is less than 30 parts by weight, the plastic deformability will not be sufficient.
It is preferable to use a mixture of bis-fatty acid amide of 40 to 60 weights and a polyethylene wax having a number average molecular weight of about 3,000 to 9,000.

The toner of the present invention is produced by dispersing a coloring agent such as carbon in a composition consisting of the bis fatty acid amide and polyethylene wax. The thermoplastic resin used, for example, polystyrene, polychlorostyrene, styrene such as styrene-acrylic acid copolymer, and polymers or copolymers of substituted products thereof, polyvinyl chloride, polypropylene, polyvinyl acetate , polyester resin, acrylic resin, silicone resin, epoxy resin,
Xylene resin, ionomer resin, furan resin, ketone resin, terpene resin, phenol-modified terpene resin, rosin, rosin-modified polyester resin, hydrogenated rosin ester, maleic acid-modified phenol resin, aliphatic cyclic hydrocarbon resin, petroleum resin, phthalate acid resin, cellulose acetate,
carboxymethyl cellulose, methyl vinyl ether,
Ethylene-acrylic acid copolymer, maleic anhydride resin, etc. can be used as the blend resin. In particular, when a mixture of polypropylene, hydrogenated rosin ester, aliphatic cyclic hydrocarbon resin, petroleum resin, or ethylene-acrylic acid copolymer is used, good pressure fixing properties can be obtained.

When the blended resin is used in combination with the composition of the present invention, the content of the composition of the present invention varies depending on the blended resin, but is preferably at least 50% by weight in the total binder of the toner.
Good fixability can be maintained if the temperature is 70% or more.

Furthermore, in order to improve transferability, cleaning performance, charging performance, etc., conventionally used waxes, charging agents, etc. may be mixed to an extent that does not impair pressure fixing performance.

Further, the same effect as described above can be obtained even if magnetic powder such as magnetite, ferrite, iron powder, etc. is added for the purpose of obtaining a magnetic toner.

In order to fix the image developed with the toner of the present invention, the transfer member to which the image has been transferred may be pressed by any conventionally known appropriate means, such as passing it between a pair of pressure-loaded rollers.

Approximately 15 to 30 kg/cm of linear pressure is suitable for the applied pressure.

EXAMPLES The present invention will be described in more detail below with reference to Examples.

Example 1 Bis fatty acid amide (product name WAX C manufactured by Hoechst) 14wt% polyethylene wax (product name PE 190 manufactured by Hoechst) 14wt% blend resin polypropylene (product name PP690 manufactured by Hoechst) 12wt% magnetite
55wt% carbon black
5 wt % of the above mixture was well dispersed in advance, melted and kneaded, allowed to cool, and then jet-pulverized to obtain a toner powder with a grain size of 5 to 20 microns.

When the thus obtained toner powder of the present invention was used for copying with a commercially available dry copying machine (Ricoh P-500 manufactured by Ricoh Co., Ltd.), clear images with no fogging were obtained, and the fixing properties were also good. there were.

Furthermore, when 100,000 sheets were continuously copied, a copy image comparable to the initial image was obtained, and no offset phenomenon or wrapping around the pressure roller occurred. 1
For the 00th copy, dye fastness test method against friction using a friction tester (J I S-10849-19
71), the fixation surface of the toner was rubbed against a white cotton cloth for friction, and the degree of coloring of the self-cotton cloth for friction was compared with the gray scale for contamination to judge the fixing performance, and it was grade 5. .

In the above toner composition, toners were manufactured with the same total content of bis fatty acid amide and polyethylene wax and the mixing ratio of both was as shown in the table below, and the fixing test described above was conducted, and the results shown in the table below were obtained. It was done.

Example 2 Bis fatty acid amide (trade name Ho5talubFA 1
(manufactured by Hoechst) 20wt% polyethylene wax (product name: PE130 manufactured by Hoechst)
20wt% aliphatic cyclic hydrocarbon (trade name 1-1i-rezR-100× manufactured by Mitsui Petrochemical Industries) 10wt% magnetite
50wt% carbon black Swt
% A magnetic toner was obtained using the above mixture in the same manner as in Example 1,
Copying and fixing tests were conducted in the same manner as in Example 1, and excellent results similar to those in Example 1 were obtained.

Examples 3 to 8 Toners were produced in the same manner as in Example 1, except that in the toner composition of Example 1, a resin mixture having the following snow amount mixing ratio was used as the resin component so that the total content was 45 wt%. . In the table, the numerical value in parentheses is the content rate in the resin component. When copies were made in the same manner as in Example 1 using the toner thus obtained, clear images were obtained, and satisfactory fixing test results were obtained as shown in the table below.

Claims (1)

[Claims] A pressure-fixable toner comprising, as a binder component, a composition comprising 30 to 70 parts by weight of bis fatty acid amides and 30 to 70 parts by weight of polyethylene wax.