JPH1090938A - Mold releasing agent for toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold releasing agent excellent in low temperature fixing property, hot offset resistance, and fluidity which is used in a heat fixing type coplying machine or printer by constituting the releasing agent from a polyamide resin having an alkyl or alkenyl group having a specified number or more of carbon atoms. SOLUTION: This mold releasing agent is formed of a polyamide resin having an alkyl or alkenyl group having 9 or more carbon atoms. The polyamide resin having an alkyl or alkenyl group having 9 or more carbon atoms is derived from a long chain alkenylsuccinic acid having an alkenyl group having 9 or more carbon atoms, and, as occasion demands, a long chain alkylcarbocxylic acid having 9 or more carbon atoms and a polyamine. As the long chain alkenylsuccinic acid having an alkenyl group having 9 or more carbon atoms, nonenylsuccinic acid, dodecenylsuccinic acid or the like is given. Of them, a long alkenylsuccinic acid having an alkenyl group having 11 or more carbon atoms is preferably used from the viewpoint of fluidity and storing property of toner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a release agent for electrophotographic toner. More specifically, the present invention relates to a release agent for toner which is excellent in low-temperature fixing property, hot offset resistance and fluidity used in a heat fixing type copying machine or printer.

[0002]

2. Description of the Related Art In an electrophotographic process using a powdery dry toner, a contact heating type fixing device (a method using a heat roll, a method using a heat roll and a paper) is used to fix toner transferred onto paper or the like. Through a film or a belt (for example, JP-A-4-70688 and JP-A-4-70688).
No. 12558) has been widely adopted. In this method, a temperature at which offset to a heat roll surface, a film or a belt occurs at a low temperature (hereinafter abbreviated as COT)
Is preferably low, and the temperature at which offset to the surface of the heat roll, film or belt occurs at a high temperature (hereinafter abbreviated as HOT) is preferably high. In order to obtain suitable COT and HOT, many methods have been proposed for widening the molecular weight distribution of the binder resin (for example, JP-A-61-215558). It is known that adding a low molecular weight polypropylene resin is effective. (For example, Japanese Patent Publication No. 52-3304)

[0003]

However, in response to recent demands for higher copy speed and lower energy fixing, there is a demand for fixing toner at a lower temperature. There is a need to lower it. For this purpose, it is effective to lower the molecular weight of the low-molecular-weight polypropylene resin to lower the melt viscosity, but on the other hand, the fluidity of the toner is reduced, and the amount of filming material adhering to the carrier is reduced. There are problems such as increase. Alternatively, use of natural wax such as carnauba wax (Japanese Patent Application Laid-Open No. 4-362953) and use of synthetic wax such as fatty acid ester and fatty acid amide (Japanese Patent Application Laid-Open No. 56-144436) have been proposed. However, there are problems such as price and quality stability, and synthetic waxes such as fatty acid esters and fatty acid amides are generally too brittle. is there.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies on a release agent for toner which does not have the above-mentioned drawbacks and exhibits excellent COT and HOT, and has reached the present invention. That is, the present invention relates to a toner release agent comprising a polyamide resin having an alkyl or alkenyl group having 9 or more carbon atoms.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The polyamide resin having an alkyl or alkenyl group having 9 or more carbon atoms of the present invention is obtained, for example, from a long-chain alkenyl succinic acid having an alkenyl group having 9 or more carbon atoms and optionally a long-chain alkyl carboxylic acid having 9 or more carbon atoms and a polyamine. Be guided. Examples of the long-chain alkenyl succinic acid having an alkenyl group having 9 or more carbon atoms include nonenyl succinic acid, dodecenyl succinic acid, pentadecenyl succinic acid, octadecenyl succinic acid, and eicosenyl succinic acid. Of these, from the viewpoint of toner fluidity and storage stability,
Preferred is a long-chain alkenyl succinic acid having an alkenyl group having 11 or more carbon atoms.

[0006] Examples of the long-chain alkylcarboxylic acid having 9 or more carbon atoms include capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachiic acid, behenic acid, fatty acid of castor oil and fatty acid of castor oil. Among these, long-chain alkyl carboxylic acids having an alkyl group having 11 or more carbon atoms are preferable from the viewpoints of fluidity and storage stability of the toner.

In producing the polyamide resin of the present invention, another organic carboxylic acid compound can be used in combination. As the organic carboxylic acid compound, acetic acid, acetic anhydride, succinic acid,
Maleic acid, fumaric acid, itaconic acid, azelaic acid,
Mesaconic acid, citraconic acid, sebacic acid, glutaconic acid, adipic acid, malonic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, nadic acid, methylnadic acid, octylsuccinic acid, and anhydrides of these acids, Examples thereof include polymerized fatty acids such as linoleic acid dimer and trimer, dodecane diacid, C21 dibasic acid, and dimer acid (polymerized fatty acid obtained by polymerizing unsaturated fatty acid such as oleic acid and linoleic acid).

Further, carbon atoms such as aliphatic polycarboxylic acids having 7 to 20 carbon atoms, such as 1,2,4-butanetricarboxylic acid and 1,2,5-hexanetricarboxylic acid, and carbon atoms such as 1,2,4-cyclohexanetricarboxylic acid. An alicyclic polycarboxylic acid having 9 to 20 carbon atoms, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, an aromatic polycarboxylic acid having 9 to 20 carbon atoms such as pyromellitic acid, and Trihydric or higher polycarboxylic acids such as anhydrides and lower alkyl (methyl, butyl, etc.) esters can also be used.

The polyamine used for obtaining the polyamide in the present invention includes ethylenediamine, propylenediamine, diaminobutane, diaminopentane,
Diamines such as diaminohexane, diaminoheptane, diaminooctane, diaminodecane and diaminododecane;
3 such as diethylenetriamine and triethylenetetramine
Amines having a valency or higher.

The content of long-chain alkenyl succinic acid and / or long-chain alkyl carboxylic acid in the polyamide resin is from 10 to 95% by weight, preferably from 15 to 95% by weight, from the viewpoint of releasability. ~ 90% by weight.

The number average molecular weight (hereinafter referred to as Mn) of the polyamide resin
2,000 to 15,000, and preferably 3,000, from the viewpoint of releasability and obtaining a sufficient HOT.
１４14,000.

The molecular weight can be measured by the following apparatus and conditions. Apparatus: HLC-802A manufactured by Toyo Soda Column: 2 TSK gel GMH6 (manufactured by Toyo Soda) Measurement temperature: 40 ° C. Sample solution: 0.25 wt% THF solution Injection amount of solution: 200 μl Detector: Refractive index detector Molecular weight calibration Curves were created using standard polystyrene.

The polyamide of the present invention can be prepared by the following method. That is, a cooling pipe, a stirring device,
A long-chain alkenyl succinic acid, a long-chain alkyl carboxylic acid and, if necessary, another organic carboxylic acid compound to be used together are charged into a reaction vessel equipped with a thermometer and a nitrogen inlet tube, and the temperature is increased while passing nitrogen gas through. After uniformly dissolving succinic acid and / or a long-chain alkyl carboxylic acid and another organic carboxylic acid compound to be used in combination, a diamine is charged,
The temperature is further increased, and the polyamide is formed while removing the water of reaction.

Since ordinary polyamides have a carboxylic acid group and / or an amine group at the terminal of the polymer, they may have an unexpected adverse effect on the charging behavior. In order to prevent this, it is desirable that the amine value and the acid value of the polyamide resin be 1 or less.

For this purpose, an excess of an amine compound is initially added and polymerization is carried out, and then acetic acid and acetic anhydride are further added to other long-chain alkylcarboxylic acids or other organic carboxylic acid compounds to be used in combination. It is effective to complete the polyamide conversion. By doing so, the terminal of the polyamide becomes almost an alkyl group, and the amine value and the acid value of the polyamide resin become 1 or less, so that there is no remarkable influence on the charging behavior, which is effective in designing the toner.

The polyamide of the present invention can be used alone or in combination with another release agent. Other release agents used in combination include polyolefin resins, fatty acid metal salts,
Fatty acid esters, fatty acid amides, alkylene bis fatty acid amides, esters of polyhydric alcohols, higher fatty acids, higher alcohols, paraffin waxes, hydrocarbon waxes,
Fischer-Tropsch wax, carnauba wax,
Montan wax and the like.

The release agent for a toner of the present invention may be used in addition to other components such as a thermoplastic resin binder at the time of toner production, or may be used by being previously kneaded and mixed with the thermoplastic resin binder. I can do it. Examples of the thermoplastic resin binder include a styrene resin, a polyester resin, and a composite thereof.

As an example of the formulation of the electrophotographic toner to be used for the toner release agent of the present invention, the thermoplastic resin binder is usually 50 to 95% and the release agent is usually 1 to 30% based on the weight of the toner. %, Usually 5 to 10% of a known coloring material (carbon black, iron black, benzidine yellow, quinacridone, rhodamine B, phthalocyanine, etc.) and magnetic powder (ferromagnetic metal powder such as iron, cobalt, nickel or magnetite, hematite) , Ferrite or the like) is usually used in an amount of 0 to 50%.

Further, as a lubricant, polytetrafluoroethylene, a low molecular weight polyolefin, a fatty acid, or a metal salt or amide thereof, and as a charge regulator,
Nigrosine, quaternary ammonium salts and the like can be included.

As an example of a method for producing an electrophotographic toner, after dry-blending each component in the above-mentioned formulation and the various additives described above, the mixture is melt-kneaded, coarsely pulverized, and finely pulverized using a jet pulverizer. Finally, a method for producing a toner having a particle size of usually 5 to 20 microns by classification is mentioned.

The electrophotographic toner can be used as a developer for an electric latent image by mixing it with carrier particles such as iron powder, glass beads, nickel powder, and ferrite, if necessary. Further, hydrophobic colloidal silica fine powder can be used to improve the fluidity of the powder. As a method for fixing the electrophotographic toner to a support (paper, polyester film, etc.), a known heat roll fixing method can be applied.

[0022]

The present invention will be further described with reference to the following examples, but the present invention is not limited by these examples. Synthesis Example 1 100 parts by weight of a long-chain alkenyl succinic acid having 30 to 30 carbon atoms in an alkenyl group was charged into a four-necked kolben equipped with a nitrogen inlet tube, a thermometer, a stirrer, and a cooling tube, and 80 ° C. while passing nitrogen through. Then, the mixture was dissolved by heating, and stirring was started, and 9 parts by weight of ethylenediamine was gradually added. Then 200
C., and a polyamidation reaction was carried out at the same temperature for 4 hours while distilling off water produced by the reaction. Further, after adding 3 parts by weight of acetic anhydride, the reaction was continued for 2 hours while collecting the generated acetic acid to obtain a releasing agent (1) for a toner of the present invention. The amine value was 0.6, the acid value was 0.2, and Mn was 6,800.

Synthesis Example 2 10 parts by weight of a long-chain alkenyl succinic acid having 20 to 28 carbon atoms of an alkenyl group, 80 parts by weight of dimer acid, and 10 parts by weight of stearic acid were placed in a nitrogen introducing tube, a thermometer, a stirrer, and a cooling tube. The mixture was charged into a four-necked kolben provided, heated to 80 ° C. while passing nitrogen gas through, and uniformly dissolved. Then, stirring was started, and 12.5 parts by weight of ethylenediamine was gradually added. Thereafter, the temperature was raised to 200 ° C., and a polyamide reaction was carried out at the same temperature for 4 hours while distilling off water produced by the reaction. After the addition of 10 parts by weight of stearic acid, the amidation reaction was continued for 2 hours to obtain a release agent (2) for a toner of the present invention. The amine value was 0.8, the acid value was 0.7, and Mn was 5,700.

Comparative Synthesis Example 1 80 parts by weight of dimer acid and 7 parts by weight of castor oil fatty acid were charged into a four-necked kolben equipped with a nitrogen inlet tube, a thermometer, a stirrer and a cooling tube, and heated to 80 ° C. while passing nitrogen through. After heating and uniform dissolution, stirring was started and ethylenediamine 11
Parts by weight were gradually added. Thereafter, the temperature was raised to 200 ° C., and a polyamide reaction was carried out at the same temperature for 4 hours while distilling off water produced by the reaction. Further, after adding 3 parts by weight of acetic anhydride, the reaction was continued for 2 hours while collecting generated acetic acid, to obtain a comparative toner release agent (3). The amine value of this is 0.
4. The acid value was 0.2 and Mn was 6,700.

Comparative Synthesis Example 2 10 parts by weight of a long-chain alkenyl succinic acid having 20 to 28 carbon atoms of an alkenyl group, 80 parts by weight of dimer acid, and 10 parts by weight of stearic acid were charged with a nitrogen introducing pipe, a thermometer, a stirrer, and a cooling pipe. Was charged into a four-necked kolben equipped with, and the temperature was raised to 80 ° C. while passing nitrogen gas to uniformly dissolve, and then stirring was started, and 11.5 parts by weight of ethylenediamine was gradually added. Thereafter, the temperature was raised to 200 ° C., and a polyamide reaction was carried out at the same temperature for 4 hours while distilling off water produced by the reaction. After 1 part by weight of acetic anhydride was further added, the reaction was continued for 2 hours while collecting generated acetic acid, to obtain a comparative toner release agent (4). Its amine value is 0.2, acid value is 0.7 and Mn is 1
It was 1,000.

Example 1 An electrophotographic toner was produced by the following method using the toner release agent (1), and an electrophotographic developer was produced.
All parts are by weight. Toner production method Styrene / acrylate copolymer 100 parts (number average molecular weight: 20,000, weight average molecular weight: 72000, glass transition point: 55 ° C.) Toner release agent (1) 4 parts Carbon black MA-100 9 parts (Mitsubishi 1 part of Aizen Spiron Black TRH (manufactured by Hodogaya Chemical Industry Co., Ltd.)
5 minutes at 60 ° C. × 60 rpm, followed by 140 ° C. × 60 r
pm for 5 minutes, and the resulting kneaded material is jet mill P
It was pulverized with JM100 (manufactured by Nippon Pneumatic).
Using an airflow classifier MDS (manufactured by Nippon Pneumatic Co., Ltd.), fine powder of 5 μm or less was cut from the finely pulverized material. Aerosil R972 (manufactured by Nippon Aerosil Co., Ltd.) is added to 50 parts of the obtained powder.
0.15 parts were uniformly mixed to obtain a toner. Developer Preparation Method 30 parts of the above toner and 800 parts of an electrophotographic carrier iron powder (F-100 manufactured by Powdertech Co., Ltd.) were mixed to obtain an electrophotographic developer (1).

Example 2 An electrophotographic developer (2) was obtained in the same manner except that the toner release agent (1) was changed to the toner release agent (2).

Comparative Example 1 An electrophotographic developer (3) was obtained in the same manner except that the toner release agent (1) was changed to the toner release agent (3).

Comparative Example 2 An electrophotographic developer (4) was obtained in the same manner except that the toner release agent (1) was changed to the toner release agent (4).

Comparative Example 3 An electrophotographic developer (5) was obtained in the same manner as above except that the toner release agent (1) was changed to Viscol 660-P (low molecular weight polypropylene manufactured by Sanyo Chemical Industries).

Comparative Example 4 An electrophotographic developer (6) was obtained in the same manner except that the toner release agent (1) was not used.

Test Results For the electrophotographic developers (1) to (6), a toner image was transferred onto paper using a commercially available copying machine (AR-5030 manufactured by Sharp Corporation), and the transferred toner on the paper was externally applied. Using a fixing machine, a fixing test was performed at a speed of 10 sheets / minute of A4 paper. The test results are as shown in Table 1.

[0033]

[Table 1]

COT The temperature of the heat roller at which the cold offset occurs. HOT Heat roller temperature at which hot offset occurs. Toner bulk density Measured using a powder tester manufactured by Hosokawa Micron Corporation. (The larger the value, the better the fluidity of the toner)

By using the release agent of the present invention, it is possible to obtain an electrophotographic developer which is excellent in low-temperature fixability, hot offset resistance and fluidity of toner.

[0036]

When the release agent of the present invention is used in an electrophotographic toner, it not only has excellent hot offset resistance, but also lowers the fluidity of the toner which has been inevitable when a low-molecular-weight polypropylene is conventionally used. Without this, the low-temperature fixability can be dramatically improved, and its usefulness is extremely high.

Claims (5)

[Claims] 1. A toner release agent comprising a polyamide resin having an alkyl or alkenyl group having 9 or more carbon atoms. 2. The polyamide resin according to claim 1, wherein the polyamide resin is derived from a long-chain alkenyl succinic acid having an alkenyl group having 9 or more carbon atoms and, if necessary, a long-chain alkyl carboxylic acid having 9 or more carbon atoms and a polyamine. Release agent for toner. 3. The content of an alkyl or alkenyl group having 9 or more carbon atoms in the polyamide resin is 10 to 95% by weight.
The release agent for toner according to claim 1 or 2, wherein 4. The polyamide resin having a number average molecular weight of 2,
The release agent for a toner according to any one of claims 1 to 3, wherein the release agent is from 000 to 15,000. 5. The toner release agent according to claim 1, wherein the polyamide resin has an amine value and an acid value of 1 or less.