JPS60256155A - Pressure fixing type toner for electrostatic charge image - Google Patents

Abstract

PURPOSE:To improve fixability, triboelectrification characteristics, and fluidity, to prevent offset, and to obtain resistance to plasticized polyvinyl chloride by mixing polycaprolactone to an epoxy resin. CONSTITUTION:Polycaprolactone or an epoxy resin which may be modified with epsilon-caprolactone is used for a binder resin and en epoxy resin is novolak type, bisphenol type, or other various modified epoxy resins, etc. alone or in combination of two or more kinds. The use of such a binder resin improves fixability to a base, such as paper in fixing by using a combinatiom of heat and pressure, prevents offset, and improves storage stability of the toner, and its fluidity, too. The image obtained by using such a toner has superior resistance to plasticized polyvinyl chloride.

Description

Detailed Description of the Invention [Field of Application of the Invention] The present invention relates to a pressure fixing type toner for electrostatic images, which has good fixing properties on a substrate such as paper when fixing is performed using a combination of heat and pressure. There is a phenomenon in which toner adheres to the fixing roll (
The present invention relates to a toner that is free from offset (hereinafter referred to as offset) and has excellent storage stability and fluidity.

[Background of the invention]

In general, styrene resins, epoxy resins, polyester resins, and the like are often used as binder resins for toners. In particular, styrene-based or styrene-acrylic resins are widely used because they have appropriate crushability, excellent charging properties, and (1) fluidity of powder. but,
After forming an image on paper with a 1-toner using such a styrene-based or styrene-acrylic resin, if it is pressed onto a polyvinyl chloride sheet and left, part or all of the toner image may peel off from the paper. There is a problem of transfer to polyvinyl chloride sheets. This is because the plasticizer such as dioctyl phthalate contained in the polyvinyl chloride sheet and the styrene resin have good compatibility.

On the other hand, epoxy resins have the property of being difficult to miscible with plasticizers due to their different solubility parameter values as mentioned above. No metastasis phenomenon is observed.

In recent years, it has become common for copies of materials to be filed and organized on polyvinyl chloride sheets, and this type of toner image transfer-free property (hereinafter referred to as PVC resistance) has become required. Ta. However, toners using epoxy resins have drawbacks such as high hygroscopicity due to the characteristics of the resin, poor charging characteristics and fluidity of the toners, and the tendency to form offsets (2).

[Purpose of the invention]

In view of the above points, the present invention makes it possible to obtain images with excellent PVC resistance, and at the same time, has good fixing properties, excellent charging characteristics and fluidity, and is also capable of producing electrostatic images without offset. The purpose of the present invention is to provide a pressure fixing type toner.

[Summary of the invention]

The present invention prevents offset by blending polycaprolactone into an epoxy resin, thereby providing images with excellent fixing properties, storage safety, and PVC resistance.

The epoxy resin mentioned above is a novolak type.

Bisphenol type, hydrogenated bisphenol type.

One type or a combination of two or more types selected from halogenated epoxies, polyfunctional epoxies, various modified epoxies, etc. can be used.

Polycaprolactone is a ring-opened heavy metal compound of ε-caprolactone and has a repeating structure of methylene groups and ester groups, and it is also possible to use an epoxy resin modified with E-caprolactone (3). The blending ratio of epoxy resin and polycaprolactone is not particularly limited, but as the amount of polycaprolactone increases, non-offset phenomenon and excellent fixing properties appear, but storage safety tends to deteriorate, and epoxy resin It is necessary to determine the amount of polycaprolactone depending on the type.

The toner of the present invention can be produced by suitably blending the above-mentioned resin with auxiliary agents such as colorants and charge control agents, wax, and fillers, kneading the mixture using a kneader, cony-dow roll, etc., and pulverizing and classifying the mixture into two parts. I can do it. The coloring agent mentioned above is carbon black.

Nigrosine, iron black, metal complex dye, chrome yellow, Hansa yellow, benzidine yellow, red iron.

Aniline red, navy blue 1 ultramarine, phthalocyanine blue, etc. Charge control agents include benzyldimethyl mexadecyl ammonium chloride, tetrapentylammonium chloride, decyl trimethylammonium chloride,
Nigrosine base, nigrosine hydrochloride, safranin, crystal (4) Violet, alkoxylated amines, ammonium sulfide, ammonium sulfonate, alkylamides, etc. Waxes include polyethylene, polypropylene, nitylene, vinyl acetate copolymer, paraffin, microcrystal wax , hydrogenated wax, carnauba wax, beeswax, polyoxyethylene, natural wax, amide wax, silicone, fluororesin, polyolefin, stearic acid, etc. Fillers include colloidal silica, hydrophobic silica, elodiyl, polysulfone,
Fused silica glass powder, talc, clay.

All known materials such as silica sand and wollastonite can be used.

[Embodiments of the invention]

Hereinafter, the present invention will be specifically explained using examples.

Example 1 Bisphenol A epoxy resin Epicoat 1007
(manufactured by Yuka Shell Co., Ltd.) 75 parts by weight, polycaprolactone,
Plaxel H-7 (manufactured by Daicel Chemical Co., Ltd.) 8 parts by weight, Carbon Black #44 (manufactured by Mitsubishi Chemical Co., Ltd. (5)) 10 parts by weight, Oil Black BY (manufactured by Orient Chemical Co., Ltd.) 5 parts by weight, Viscol 550P (Sanyo Chemical Co., Ltd.) 2 parts by weight of the mixture was mixed using a co-kneader, and after cooling, it was crushed and classified into two parts to obtain a toner having a particle size of 5 to 25 μm.

The resulting toner and carrier are mixed to make a developer, which is used to develop an electrostatic image formed by ordinary electrophotography.The resulting image is then transferred onto transfer paper, and the surface is fixed with Teflon. Using a pressure roller whose surface was made of silicone rubber, the image was brought into pressure contact with the fixing roller at various temperatures to fuse and fix the image. Next, in order to investigate whether the fused image was transferred to the surface of the fixing roller and an offset phenomenon occurred, after each fixing operation, a transfer paper without an image was brought into pressure contact with the fixing roller under the same conditions. , stains caused by toner offset on the transfer paper were observed.

As a result, the non-offset range in which the toner offset phenomenon does not occur is 100 to 150°C, and the fixability was determined by the fixability parameters when a peeling test using cellophane tape (6) was performed on the black solid developed area. A certain D/D o was 0.92, which caused no practical problems and was superior to the fixability (0.66) by conventional heat fixing. In addition, after fixing the image, dioctyl phthalate 50
% polyvinyl chloride sheet at 50° C. for 3 days, there was no contamination of the vinyl sheet.

Implementation area 2 Bisphenol A epoxy resin, Epicoat 1001
A toner was prepared and tested in the same manner as in Example 1, except that 67 parts by weight of Polycaprolactone H-1 (manufactured by Yuka Shell Co., Ltd.) and 7.16 parts by weight of Polycaprolactone H were used. As a result, the non-offset range is 100-180℃, and the fixability is D/Do
was 0.83, and there was no problem in practical use. Furthermore, no staining occurred even when the film was brought into close contact with a polyvinyl chloride sheet at 50° C. for 3 days.

Example 3 Bisphenol A epoxy resin, Epicote 1009
, 78 parts by weight, polycaprolactone, Plaxel H-4
A toner was prepared and tested in the same manner as in Example 1, except that 5 parts by weight (manufactured by Daicel Chemical Industries, Ltd.) (7) was used. As a result, the non-offset range is 100-150
℃, and the fixing property was D/Do of 0.80, which caused no practical problems. In addition, polyvinyl chloride sheet 60℃
There was no contamination of the vinyl sheet even after 3 days of contact.

Example 4 Bisphenol A epoxy resin, Epicote 1007
, 58 parts by weight, lactone-modified epoxy resin.

A toner was prepared and tested in the same manner as in Example 1, except that 25 parts by weight of Plaxel G701 (manufactured by Daicel Chemical Co., Ltd.) was used. As a result, the non-offset range is 100-18
The temperature was 0° C., and the fixing property D/DO was 0.90, which caused no practical problems. In addition, polyvinyl chloride sheet and 60”C
There was no contamination even after 13 days of close contact.

Example 5 Bisphenol A epoxy resin, Epicoat 1009
, 67 parts by weight, lactone-modified epoxy resin Plaxel G
A toner was prepared in the same manner as in Example 1 except that 16 parts by weight (8) parts of 401 (manufactured by Daicel Chemical Co., Ltd.) were used.
The test was conducted. As a result, the non-offset range is 100~
The temperature is 160°C and the fixing property is D/D.

was 0.88, which caused no practical problems. Furthermore, no staining occurred even when the film was brought into close contact with a polyvinyl chloride sheet at 60° C. for 3 days.

Agent: Patent Attorney Akio Takahashi (9)

Claims (1)

[Claims] (2) A pressure fixing toner for electrostatic images, which is characterized by containing at least an epoxy resin and polycaprolactone.