JPH0313963A - Toner composition for recording image - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] In order to provide a toner composition having excellent pressure fixing properties regarding a toner composition for image recording, a bifunctional amide monomer represented by the following formula: Y ( In the above formula, Y may be the same or different and each represents an amide group component having at least one hydroxyl group as a substituent, and R is a saturated or unsaturated cyclic group bonding the Y component. ) as a binder resin.

[Industrial application field]

The present invention relates to a toner composition for image recording. More specifically, the present invention relates to toner compositions useful in magnetic brush developers, particularly non-magnetic-component developers, used in electrophotography and the like.

Note that hereinafter, the toner composition may be referred to as a toner.

[Conventional technology]

As an electrophotographic method, the method described in U.S. Pat. An electrical latent image is formed by irradiating a light image onto the electrostatic latent image carrier by various means, and then the latent image is developed and visualized using colored fine particles called toner. After transferring the toner image to paper etc. according to the
Printed matter is obtained by fixing using pressure, heat, light, etc.

As a developing method using the toner, the magnetic brush developing method described in US Pat. No. 2,786,439 has been widely used. To explain the magnetic brush development method in detail, a magnetic developer is used, in which a magnetic carrier and a toner are mixed and stirred and frictionally charged to opposite polarities. By rubbing the surface of the electrostatic latent image carrier, only the toner is separated and adhered by electric attraction, and the electrostatic latent image is developed. Conventionally, the magnetic developer is a so-called two-component magnetic developer, more specifically, the carrier has an average particle diameter l.
Magnetic powder such as iron powder, ferrite powder, magnetant powder, etc. of O〇- grade, or resin-coated powder of these magnetic powders is used as the toner, and a coloring agent etc. is dispersed in a binder resin made of natural or synthetic polymer material. The average particle size is 10-
Non-magnetic insulating powder that has been pulverized to a certain degree is commonly used.

Currently, there is a growing need for small-sized optical printers that can print Chinese characters and graph ink with low noise as output devices for office automation. The fixing method for these printers has traditionally been hot roll fixing, which melts the toner and fixes it on the paper. Furthermore, the pressure fixing method is attracting attention because of its advantages such as a simplified mechanism. Since the toner applied to this method is fixed on paper only by pressure, it is necessary to use a soft resin as the binder resin for the toner, unlike that for hot roll fixing which has specific heat-melting properties. However, the fixing properties are considerably inferior to that of hot roll fixing, and it is necessary to develop a binder resin with excellent fixing properties in order to put this into practical use as a fixing method for printers.

(Problems to be Solved by the Invention) An object of the present invention is to provide a toner composition having excellent pressure fixing properties.

[Means to solve the problem]

According to the present invention, the above-mentioned object is achieved by a bifunctional amide monomer RY represented by the following formula (in the above formula, Y may be the same or different, each containing at least one hydroxyl group). This is achieved by a toner composition for image recording, characterized in that it has an amide group component as a substituent, and R represents a saturated or unsaturated cyclic group bonding the Y component as a binder resin. I can do it.

As described above, the amide monomer used as the binder resin in the toner composition of the present invention is difunctional, and each amide group component Y contains at least one
hydroxyl groups, preferably a total of 2 hydroxyl groups. Care must be taken that too many hydroxyl groups may result in unacceptably high tack, which will interfere with the dry process. In addition, a group R that connects two Y components
can be a saturated or unsaturated cyclic group, such as an aromatic hydrocarbon group such as a phenylene group, an alicyclic hydrocarbon group such as a cyclohexylene group, etc. These groups R may be substituted as necessary.

A preferred example of an amide monomer useful as a binder resin is as follows: n-3 to 30 n=3 to 30 The binder resin described above can be added to a toner composition in an amount commonly used in this technical field. It can be used inside. In the practice of the present invention, the amount incorporated is not particularly limited, but is generally preferably about 90 to 96% by weight based on the total amount of the toner composition.

In addition to the binder resin described above, the toner composition can contain various colorants, such as charge control agents and additives such as wax. Blending, granulation, and other processes of these components can also be performed using techniques common in this technical field.

Although the toner composition of the present invention will be described below with particular reference to electrophotography, it should be understood that it can also be used for other image recording purposes.

[For production]

The causes of poor toner fixing properties are: ■ Poor adhesion between the toner image and paper, causing peeling at the interface of the paper toner image due to external force; ■ Cohesive force inside the toner layer of the fixed toner image is small. There are two cases in which peeling occurs inside the toner layer due to external force.

In order to reduce both of these peelings and improve toner fixation, a binder resin with high penetrating power into paper fibers and high chemical attraction with the fibers is used. It is necessary to use resin.

Since the binder resin used in the present invention has at least two hydroxyl groups in one molecule, it has a strong chemical attraction with paper and can reduce the peeling of the paper. Furthermore, due to the presence of these two hydroxyl groups, in addition to intermolecular hydrogen bonds between amides, intermolecular hydrogen bonds between the amide and the hydroxyl group and between the hydroxyl groups are considered to occur. Therefore, the cohesive force of the toner itself is strong, and the peeling of the toner can be reduced. From the above, by using the resin of the present invention, a toner having excellent pressure fixing properties can be obtained.

〔Example〕

Next, the present invention will be explained with reference to some examples and comparative examples.

backyard dish top The following toner components were mixed in the stated amounts.

Amide monomer resin: n=18 94 parts by weight Dye Nioil Black BY (manufactured by Orient Chemical Co., Ltd.) 3
Weight part carbon black: Black Pe5rls L (
(manufactured by Cabot Corporation) 3 parts by weight This mixture was melt-kneaded and then pulverized and classified to obtain an average particle size of 12-
An insulating toner was obtained. Furthermore, powder images of this toner with different toner layer thicknesses (15 to 30) were created on plain paper using a mini-developing machine, and the toner was passed through the pressure fixing section of a pressure fixing tester to form a fixed image of the toner. I got it. In addition, the linear pressure of the pressure fixing part of this test machine is 15 kg/cm, and the nip length is 0.
．． It is 6 Peng. Next, apply adhesive tape (
Scotch Mende, Ingtave, manufactured by Sumitomo 3M Co., Ltd.) are attached with a constant load and at a constant speed (2.5 CIl/s).
The fixation rate was determined by the ratio of the optical density before and after the tape was peeled off, and the fixability was evaluated.

As a result of the evaluation test, it was found that the fixing rate was constant regardless of the thickness of the toner powder image after development, and that the pressure fixing properties obtained were good at over 80%. Satisfactory results were also obtained when the above process was repeated with n of the monomer resin changed to 5 and 28.

A toner was prepared by repeating the method described in Example 1 above, and its fixability was evaluated. However, in this example, for comparison, a polyamide resin represented by the following formula was used as the binder resin.

+ C0-NH-(CHf+T-NO-Co-R罎T(
(In the above formula, m is 20 and n is 30.) As a result of the evaluation test, the fixing rate was around 50% when the powder image thickness was between 15 and 30 mm, indicating that the pressure fixing performance was quite poor. It turns out.

A prototype toner was produced by repeating the method described in Example 1 above, and its fixability was evaluated. However, in this example, for comparison, a hydroxyl group-free amide monomer resin represented by the following formula was used as a binder resin.

C8r(C)I f+TI-NH-CO(C8tTCR
As a result of the s evaluation test, the fixing rate was as good as 85% at a powder image thickness (15, n) in which the cohesive force of the toner itself was not involved, but beyond this, the fixing rate rapidly decreased and the cohesion It becomes 50% at the thickness of the powder image (22m) where power dominates, and from there it is 301! It was found that the fixing performance was always 50% up to m, which was quite poor.

2 servings 1 The following toner components were mixed in the stated amounts.

Amide monomer resin: 94 parts by weight Dye Nioil Black BY (manufactured by Orient Chemical Co., Ltd.) 3
Weight part carbon black: Black Pe5rls L (
(manufactured by Cabot Corporation) 3 parts by weight This mixture was melt-kneaded, crushed and classified to obtain an insulating toner having an average particle size of 12. Furthermore, powder images of this toner with different toner layer thicknesses (15 to 30 μm) are created on plain paper using a mini-developing machine, and the toner images are passed through the pressure fixing section of a pressure fixing tester to create a fixed image of the toner. Obtained. In addition, the linear pressure of the pressure fixing part of this testing machine was 15 kg/c+*, and the nip length was 0.6 tn. Next, an adhesive tape (Scotch Mending Tape, manufactured by Sumitomo 3M) was applied to this fixed image with a constant load (1 kg), and it was peeled off at a rate of 1.5 cm/3 to determine the optical density before and after the tape was peeled off. The fixing rate was determined by the ratio and the fixing performance was evaluated.

As a result of the evaluation test, it was found that the fixing rate was constant regardless of the thickness of the toner powder image after development, and that the obtained pressure fixing performance was as good as 80% or more.

Satisfactory results were also obtained when the above process was repeated with n of the amide monomer resin used changed to 5 and 28.

〔Effect of the invention〕

Use of certain difunctional amide monomers according to the present invention as binder resins in toner compositions can significantly improve the pressure fixability of the resulting toner compositions.

Claims (1)

[Claims] 1. A bifunctional amide monomer represented by the following formula: Y-R-Y (in the above formula, Y may be the same or different, each of which has at least one hydroxyl group as a substituent) and R represents a saturated or unsaturated cyclic group bonding the Y component) as a binder resin.