JPH0693133B2 - Toner resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a resin composition for toner used in electrophotography and the like, and more specifically to a so-called dry developing method among methods for developing an electrostatic image. The present invention relates to a resin composition for toner used.

(Prior Art) In a dry development method, toner is usually charged by friction with iron powder or glass beads called a carrier, which is then attached to an electrostatic latent image on a photoconductor by an electric attraction and then It is transferred onto paper and fixed by a heat roll or the like to form a permanent visible image.

Generally, in toner, in order to adjust the charge amount at the time of friction,
For example, when imparting a positive charge, a charge control agent such as a nigrocyanine dye was added, but the addition of the expensive control agent increases the price of the toner, but in some cases, the control agent bleeds. was there.

Therefore, it is known to introduce an amino group-containing monomer as a resin component into the toner resin itself (for example, JP-A-48-102633).

However, although the above conventional amino group-containing polymer is imparted with a positive charging property, it has a strong odor peculiar to an amino group, and thus it has been difficult to put it to practical use.

(Problems to be Solved by the Invention) An object of the present invention is to provide a resin composition for positively chargeable toner, which does not have an offensive odor peculiar to amino groups.

(Means for Solving Problems) The present invention is directed to a styrene monomer, an acrylic acid or methacrylic acid ester monomer, an acid group-containing vinyl monomer, and an acrylic or methacrylic tertiary amine monomer. The main component of the copolymer is a copolymer having four different kinds of monomers as essential constituent units.

Specific examples of the styrene-based monomer used in the present invention include, in addition to styrene, for example, O-methylstyrene and m.
-Methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn -Octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4
-Dichlorostyrene and the like can be mentioned.

The toner resin must have appropriate pulverizability during toner production, and the content of the styrene component in the copolymer must be
If the content is 30% by weight or less, the pulverizability tends to decrease, so the content is usually 30% by weight or more, preferably 40% by weight or more.

Specific examples of the acrylic acid or methacrylic acid ester-based monomer used in the present invention include methyl acrylate,
Ethyl acrylate, propyl acrylate, acrylic acid n
-Butyl, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacryl Examples thereof include acrylic acid such as n-octyl acid, dodecyl methacrylate and stearyl methacrylate, or alkyl esters of methacrylic acid, such as ethyl acrylate, propyl acrylate, butyl acrylate, methyl methacrylate, ethyl methacrylate, methacrylic acid. Propyl, butyl methacrylate and the like are particularly preferably used.

The styrene-based monomer and the acrylic or methacrylic acid ester-based monomer are usually contained in the copolymer in an amount of 80 to 9
Contains about 9.5% by weight.

Examples of the vinyl monomer containing an acid group used in the present invention include acrylic acid, methacrylic acid, maleic acid, and an esterification reaction of a hydroxyl group-containing acrylic acid derivative or methacrylic acid derivative with a dicarboxylic acid. The half-ester compound of the obtained structure is mentioned. The dicarboxylic acid such as maleic acid may be an acid anhydride.

And the above-mentioned half-ester compound, that is, the carboxyl group-containing compound is, for example, a derivative of an aliphatic dicarboxylic acid such as malonic acid, succinic acid, or darthalic acid or an aromatic dicarboxylic acid such as phthalic acid, and a hydroxyl group-containing acrylic acid or methacrylic acid. It is obtained by an esterification reaction with.
The dicarboxylic acid is a halogen group element, a lower alkyl group,
A hydrogen atom may be substituted with an alkoxy group or the like, or may be an acid anhydride.

The hydroxyl group-containing acrylic acid or methacrylic acid derivative may be acrylic acid or methacrylic acid to which 1 mol or 2 mol or more of alkylene oxide such as ethylene oxide or propylene oxide is added, or acrylic acid or methacrylic acid is added. It may be a hydroxyalkyl ester obtained by esterifying a dihydric alcohol such as propylene glycol.

The half-ester compound is, for example, one of the following general formulas (1)
~ (4).

(1) (R ₁ and R ₂ are H or CH ₃ , m is 1 to 14, and n is 0 to 8.) (2) (R ₃ and R ₄ are H or CH ₃ , h is 1 to 14, X is H, a halogen group element,
It represents a lower alkyl or alkoxy group. ) (3) (R ₅ is H or CH ₃ , j is 3 to 6, and k is 0 to 8.) (4) (R ₆ is H or CH ₃ , l is 3 to 6, Y is H, a halogen group element, a lower alkyl group or an alkoxy group.) As a preferable specific example of the half-ester compound, succinic acid mono (meth) is preferable. Acryloyloxyethyl ester, succinic acid mono (meth) acryloyloxypropyl ester, glutaric acid mono (meth) acryloyloxyethyl ester, phthalic acid mono (meth) acryloyloxyethyl ester, phthalic acid mono (meth) acryloyloxypropyl ester, etc. Can be mentioned.

The present inventors have found that the introduction of the above-mentioned vinyl monomer containing an acid group into the copolymer can prevent or reduce the generation of malodor caused by the tertiary amine monomer described below. However, it was further found that this copolymer had no coloration, which is also considered to be caused by the tertiary amine monomer, and had an unexpected effect of preventing adhesion of a color scale to the reaction vessel during polymerization. .

The acrylic tertiary amine or methacrylic tertiary amine in the present invention refers to a tertiary amine containing an acryloyl group or a methacryloyl group, preferably a general formula (However, R ₁ represents hydrogen or an alkyl group having 1 to 5 carbon atoms, and R ₂ and R ₃ represent an alkyl group having 1 to 5 carbon atoms.
R ₄ represents an alkylene group having 1 to 5 carbon atoms. ), And more preferable examples thereof include (meth) acrylic acid esters such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate, and dimethylacrylamide.

If the content of the tertiary amine monomer is too small, the positive charge imparting property is not expressed, and if it is too large, the moisture resistance of the copolymer tends to be lowered. Ten
%, Preferably 1 to 5% by weight.

The content of the above-mentioned vinyl monomer containing an acid group is usually about 0.2 to 2 mol per 1 mol of the above-mentioned tertiary amine monomer. This is because if it is less than 0.2 mol, the deodorizing effect of the tertiary amine is not exhibited, and if it exceeds 2 mol, the positive charging property tends to be weakened.

The method for producing the copolymer having the above-mentioned four kinds of different components as essential constituent units used in the present invention is not specified at all, and examples thereof include suspension polymerization method, solution polymerization method, emulsion polymerization method and block polymerization method. The well-known method is used, but the suspension polymerization method and the solution polymerization method are frequently used, and the solution polymerization method is particularly preferable.

To the resin for toner of the present invention, vinyl acetate, vinyl propionate, vinyl chloride, ethylene and the like may be introduced as a copolymerization component within a range in which the object of the present invention can be achieved,
Further, it does not matter even if a polymer of the above monomer is blended. Further, waxes such as epoxy resin and low molecular weight polypropylene resin may be mixed.

(Examples) Examples of the present invention will be shown below. The anonymous number represents the number of parts by weight.

Example 1 400 g of toluene was placed in a two-separable flask, the air was replaced with nitrogen gas, and then 850 g of styrene, 92.5 g of n-butyl acrylate and dimethylaminoethyl were stirred and heated to the boiling point of toluene. Acrylate 37.5 g, succinic acid monoacryloyloxyethyl ester 20 g, and azobisisobutyronitrile (AIBN) as a polymerization initiator
Solution polymerization was carried out while dropwise adding a mixture in which 40 g was dissolved over 2.5 hours.

After the completion of dropping the mixture, the mixture was aged at the boiling point of toluene for 1 hour with stirring, and then the system temperature was further adjusted to 180 ° C.
Toluene was removed under reduced pressure while gradually raising the temperature to 0 ° C. to obtain a styrene-acrylic acid n-butyl-dimethylaminoethyl acrylate-succinic acid monoacryloyloxyethyl ester copolymer. This copolymer resin was cooled and pulverized to obtain a flaky resin A of the present invention.

The obtained resin was scarcely colored, and the colored scale was not attached to the upper part of the separable flask.

Resin A is further finely pulverized with a jet mill to obtain fine particle resin A having an average particle size of about 13 to 15 microns, which is mixed with an iron powder carrier and then the charge amount is measured by a blow-off powder charge amount measuring device by a conventional method. As a result, a charge amount of +17 μC / g was exhibited.

Furthermore, when the odor of the fine particle resin A was checked, there was no amine odor.

Examples 2 to 8 Using the monomers shown in Table 1, copolymers were synthesized in the same manner as in Example 1, finely pulverized and then mixed with a carrier, and the charge amount and the like were measured.

The results are shown in Table 1.

Comparative Examples 1 and 2 Using the monomers shown in Table 2, a copolymer was synthesized by the same procedure as in Example 1, finely pulverized and then mixed with a carrier, and the charge amount, the colorability, etc. were measured. . The results are shown in Table 2.

(Effects of the Invention) The toner resin of the present invention is configured as described above, and contains an acid together with a styrene monomer, an acrylic acid or methacrylic acid ester monomer, and an acrylic or methacrylic tertiary amine monomer. Since the main component is a copolymer having a vinyl monomer containing a group as a constitutional unit, it has no amine odor or an extremely slight odor as compared with a conventional positively chargeable resin having a tertiary amine as a copolymer component. That is, it has a practically useful effect.

Further, the above-mentioned copolymer used in the present invention does not cause a colored scale to adhere to the reaction vessel during polymerization and the copolymer itself is not colored, and therefore the composition of the present invention is suitable for use in a color toner.

Claims (2)

[Claims] 1. A copolymer having a styrene monomer, an acrylic acid or methacrylic acid ester monomer, an acid group-containing vinyl monomer and an acrylic or methacrylic tertiary amine monomer as a constituent unit. A resin composition for a toner, which comprises a coalesce as a main component. 2. A half-ester compound having a structure in which a vinyl monomer having an acid group is obtained by an esterification reaction of a hydroxyl group-containing acrylic acid or methacrylic acid derivative with a dicarboxylic acid, acrylic acid, methacrylic acid, and The toner resin composition according to claim 1, which is at least one monomer selected from maleic acid.