JPS6223053A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To prevent a transfer paper from winding round a roller at the time of fixing and from jamming by allowing the softening points of a toner and a low molecular polyolefin measured by the ring and ball method to satisfy a specified relational expression. CONSTITUTION:In the electrostatic charge image developing toner containing a colorant, a binder resin, and the low molecular olefin polymer or copolymer, the softening point of the toner measured by the ball and ring method X deg.C, and that of the polyolefin Y deg.C are allowed to satisfy the following relational expression: Y<=0.9X+40, and this relational expression is established by a number of experimental results, and the toners satisfying this relational expression can prevent the transfer paper from winding round the fixing roller and jamming, and can enhance fixability at low temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention particularly relates to a toner for developing electrostatic images in electrophotographic full-color copying machines and the like.

Prior Art Conventionally, toners for developing electrostatic images containing colorants, binder resins, and low molecular weight polypropylene mainly focus on preventing offset development, so they tend to wrap around the fixing roller near the lower limit temperature of fixing. Not enough consideration was given to jam.

Purpose The present invention has an object to prevent a transfer paper from being wrapped around a fixing roller during fixing or from jamming, especially in an electrophotographic full-color copying machine or the like.

Structure The inventors of the present invention discovered that transfer paper wrapping around the fixing roller during fixing and jamming are most likely to occur near the lower limit temperature of toner fixing, and thus came up with the present invention. .

That is, in the present invention, in a toner containing a colorant, a binder resin, and a low molecular weight olefin polymer or copolymer, the ring and ball softening point of the toner is set to X°C, and the ring and ball softening point of the low molecular weight olefin is set to X°C. Y''C, which is an electrostatic image developing toner characterized by satisfying the following relational expression.

Y≦0.9X + 40 In the present invention, the olefin polymer includes polypropylene; polyethylene; butene-1, pentene-1, hexene-1, bebutene-1, octene-1, nonene-1
, decene-1 or their homologues with different positions of the unsaturated bond or e.g. 3-methyl-1-butene, 3-
Methyl-2-pentene, 3-propyl-5-methyl-2
Examples include homopolymers whose monomers include those having an alkyl group introduced as a branched chain, such as -hexyl.

In addition, as a copolymer, a copolymer containing at least two or more types of olefin as a monomer component, a copolymer containing at least one type of olefin and at least one type of monomer other than olefin as a monomer component Examples include olefin copolymers.

It is desirable that these have high compatibility with the binder resin, and also have a relatively low molecular weight. For example, polypropylene has an average molecular weight of 1000 to 4500.
0, especially about 2000 to 6000, for polyethylene, 1000 to 10000, especially 1000 to 50
00, less than 10,000 for those with 4 or more carbon atoms, especially about 3,000 to 8,000, and 10 for copolymers.
000 or less, preferably about 3000 to 8000.

As the binder resin, resins that have been widely used in electrophotographic toners include α-methylene aliphatic monocarboxylic acids such as methyl acrylate, n-butyl acrylate, isobutyl acrylate, and butyl methacrylate. Examples include polymers of esters, copolymers of two or more of these monomers, copolymers of these and styrene, polystyrene, rosin-modified phenolic resins, polyurethane resins, polyester resins, and the like. Particularly preferred are styrene resins.

More details about styrene resin include polystyrene, chloropolystyrene, poly-α-methylstyrene,
Styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-acrylic acid ester copolymer, styrene-acrylic acid methyl copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer,
Styrene-octyl acrylate copolymer, styrene-phenyl acrylate copolymer, etc.), styrene-methacrylate copolymer (styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-methacrylate copolymer, etc.) styrene-α-methyl chloroacrylate copolymer, styrene-acrylonitrile-acrylic acid ester copolymer, etc.).

One or a mixture of two or more of these thermoplastic resins can be used as the binder resin.

A suitable pigment or dye is used as the colorant in the present invention. For example, carbon black, nigrosine dye, aniline blue, carfoil blue, chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green offsalate,
Lamp black, rose bengal, etc. and mixtures thereof are used and need to be included in the toner in an amount sufficient to color the toner so that it can be developed to form a visible image.

The above-mentioned relational expression in the present invention has been determined as a result of many tests, and a product that satisfies this relational expression will prevent wrapping around the fixing roller, jam, etc. even during low-temperature fixing, and will have good low-temperature fixing properties. is improved.

The present invention relates to a color toner for developing an electrostatic image that can be used in a multicolor superimposed color electrophotographic copying machine that superimposes three types of toner, yellow, magenta, and cyan, or four types of toner, yellow, magenta, cyan, and black. The effect is particularly effective.

Hereinafter, the present invention will be specifically explained using Examples and Comparative Examples.

Example 1 Styrene-methacrylic acid copolymer (85:15) 70 parts by weight Carbon black (#44) 10 parts by weight Nigrosine base EX 5 parts by weight Low molecular weight polyethylene (trade name: Piskor 660P, manufactured by Sanyo Chemical Co., Ltd.) (R&
B-145°C) 5 parts by weight Polyester resin 30 parts by weight The above materials were mixed and pulverized in a ball mill, melted and mixed in a hot roll mill, cooled, coarsely pulverized in a hammer mill, and then finely pulverized in an air jet type pulverizer. do. The obtained fine powder was classified to produce a toner having an average particle size of about 13 to 15 μm. The ring and ball softening temperature (abbreviated as R&B) of this toner was 122°C.

A developer was prepared by mixing 4 parts by weight of this toner with 96 parts by weight of an iron powder carrier having an average particle size of about 50 to 80 μm, and an electrostatic image formed by a conventional electrophotographic method was developed with this developer. After that, the toner image was transferred onto a transfer paper, and the fixing roller having a smooth surface made of Teflon (manufactured by DuPont) was used without supplying offset prevention liquid at 155±5°C, which is around the lower limit fixing temperature. The toner image was fused and fixed by pressure contact. When this operation was repeated for 100 sheets and the winding around the fixing roller was observed, winding did not occur even - times.

Comparative Example 1 Styrene-methacrylic acid copolymer (85:15) 70 parts by weight Polyester resin 30 parts by weight Carbon black (#44) 5 parts by weight Low molecular weight polypropylene (trade name: Viscol 330P, manufactured by Sanyo Chemical Co., Ltd.) (R&
B-152°C) 5 parts by weight Nigrosine base EX 10 overlapping parts The above material was treated in the same manner as in Example 1 to prepare a toner and use it as a sample.

The R&B of this toner was measured and found to be 122°C. When fixing was carried out under the same conditions as in Example 1, 100
More than 50 of the sheets became jammed due to twisting.

Example 2 Styrene-methacrylate acid copolymer (70:30
) 95 parts by weight low molecular weight polyethylene (product name: Viscol 660P,
(manufactured by Sanyo Kasei) (R&B-145°C) 5 parts by weight Nigrosine base EX 3 parts by weight Phthalocyanine blue 11 parts by weight The above materials were treated in the same manner as in Example 1 to prepare a toner and use it as a sample. The R&B of this toner was measured and found to be 120°C.

The same operation as in Example 1 was performed except that this toner was used as a fixing roller whose surface was made of silicone rubber, and the fusing temperature was set to 145±5°C.
Regarding 00 sheets, jamming around the fixing roller was observed. As a result, not a single sheet jammed.

Comparative Example 2 Styrene-methacrylate acid copolymer (70:30
) 70 parts by weight low molecular weight polypropylene (product name: Viscol 550P
, Sanyo Kasei II) (R&B=150°C) 5 parts by weight Nigrosine Base EX 3 parts by weight Phthalocyanine Blue 5 parts by weight The above materials were treated in the same manner as in Example 1 to prepare a toner and used as a sample. This toner's R
&B was measured and found to be 120°C.

This toner was fixed under the same conditions as in Example 2, and jams on 100 sheets were observed, and 30 or more sheets were jammed.

Example 3 Styrene-methacrylic acid copolymer (85:15) 50 parts by weight Nigrosine base EX 5 parts by weight Carbon black (#44) 5 parts by weight Polyester resin
50 parts by weight AC polyethylene 629 (Allied Chemical) (R&B = 104°C) 10 parts by weight After mixing and pulverizing the above materials in a ball mill, melt-kneading in a hot roll mill, cooling and pulverizing, coarsely pulverizing in a hammer mill, and then air jet method. Finely grind with a fine grinder. The obtained fine powder was classified to produce a toner having an average particle size of about 13 to 15 μm. The R&B of this toner was 108°C.

A developer was prepared by mixing 4 parts by weight of this toner with 96 parts by weight of an iron powder carrier having an average particle size of about 50 to 80 μm, and an electrostatic image formed by a conventional electrophotographic method was developed with this developer. After that, the toner image was transferred onto transfer paper, and the fixing roller having a smooth surface made of Teflon (manufactured by DuPont) was used without supplying an anti-offset liquid at 130±5°C, which is around the minimum fixing temperature. The toner image was fused and fixed by pressure contact. When this operation was repeated for 100 sheets and the winding around the fixing roller was observed, winding did not occur - times as well.

Comparative Example 3 Styrene-methacrylic acid copolymer <85: 15) 50 parts Nigrosine base EX 5 parts by weight Carbon black 5 parts by weight Polyester resin
50 parts by weight AC polyethylene 392 (Allied Chemical) (R&B -138°C) 10 parts The above material was treated in the same manner as in Example 1 to prepare a toner and use it as a sample. The R&B of this toner was measured and was 108.
It was ℃. When fixing was carried out under the same conditions as in Example 1, more than 50 sheets out of 100 were curled and jammed.

Example 4 Styrene-methacrylate acid copolymer (70:30
) 60 parts by weight Nigrosine Base EX (Orient Chemical) Triple chain part phthalocyanine blue 5 parts by weight Polyester resin 40 parts by weight AC polyethylene 629 (Allied Chemical) (R&B=104°C) 10 parts by weight The above materials were used in the same manner as in Example 1. A toner was prepared and used as a sample. The R&B of this toner was measured and was 11.
It was 0°C.

The same procedure as in Example 1 was performed except that this toner was used as a fixing roller whose surface was made of silicone rubber, and the fusing temperature was 135±5°C.
Regarding 00 sheets, jamming around the fixing roller was observed. As a result, not a single sheet jammed.

Comparative Example 4 Styrene-methacrylate acid copolymer (70:30)
6 parts 1 part nigrosine base EX 3 parts phthalocyanine blue 5 parts polyester resin
40 parts by weight AC polyethylene 316 (Allied Chemical) (R&B = 140°C) 10 parts by weight The above materials were treated in the same manner as in Example 1 to prepare a toner and used as a sample. The R&B of this toner was measured and found to be 110°C.

When the toner was fixed under the same conditions as in Example 2 and jams were observed on 100 sheets, 30 or more sheets were jammed.

Example 5 Styrene-methacrylic acid copolymer (85:15) 75 parts by weight Nigrosine base EX 5 parts by weight Carbon black (#44) 5 parts by weight Polybutene-1 (average molecular fi 8,000) (R&B = 150 ℃）5
Part by weight Polyester resin 25 parts by weight The above materials were mixed and ground in a ball mill, melted and kneaded in a hot roll mill, cooled, coarsely ground in a hammer mill, and then finely ground in an air jet type pulverizer. The obtained 1q fine powder was classified to prepare a toner having an average particle size of about 13 to 15 μm. The R&B of this toner was 127°C.

A developer was prepared by mixing 4 parts by weight of this toner with 96 parts by weight of an iron powder carrier having an average particle size of about 50 to 80 μm, and an electrostatic image formed by a conventional electrophotographic method was developed with this developer. After that, the toner image was transferred onto a transfer paper, and the fixing roller having a smooth surface made of Teflon (manufactured by DuPont) was used without supplying an anti-offset liquid at 160±5°C, which is around the minimum fixing temperature. The toner image was fused and fixed by pressure contact. When this operation was repeated for 100 sheets and the winding around the fixing roller was observed, winding did not occur even - times.

Comparative Example 5 Styrene-methacrylic acid copolymer (85: 15) 75! Parts by weight Nigrosine base EX 5 parts by weight Carbon black (#44) 5 parts by weight Polybenthene-1 (
Average molecular weight 7,000) (R&B-160°C) 5 parts by weight Polyester resin 25 convex parts The above material was treated in the same manner as in Example 1 to prepare a toner and use it as a sample. When the R&B of this toner was measured, when fixing was performed under the same conditions as in Example 1, more than 50 sheets out of 100 sheets were curled and jammed.

Example 6 Styrene-methacrylate acid copolymer (70:30
) 65 parts by weight Nigrosine Base EX (Orient Chemical) 5 parts by weight Phthalocyanine Blue 5 parts by weight Polybutene-1
(Average molecular weight 3,000) (R&B -145℃
) 5 parts by weight Polyester resin 35 parts by weight The above materials were treated in the same manner as in Example 1 to prepare a toner and used as a sample.

The R&B of this toner was measured and found to be 117°C.

The same procedure as in Example 1 was carried out except that this toner was used as a fixing roller whose surface was made of silicone rubber, and the melting temperature was 145±5°C.
Regarding 00 sheets, jamming around the fixing roller was observed. As a result, not a single sheet jammed.

Comparative Example 6 Styrene-methacrylate acid copolymer (70:30
) 65 parts Nigrosine base EX 5 parts by weight Phthalocyanine blue 5 parts by weight Polybutene-1 (average molecular m8,000) (R&B = 155°C) 5 parts by weight Polyester resin 35 parts by weight The above materials were the same as in Example 1 A toner was prepared and used as a sample.

The R&B of this toner was measured and found to be 117°C.

When this toner was fixed under the same conditions as in Example 2 and jams were observed on 100 sheets, 30 or more sheets were jammed.

Example 7 Styrene-methacrylic acid copolymer (85:15) 80 parts by weight Nigrosine Base EX (Orient Chemical) 5 parts by weight Carbon black (#44) 5 parts by weight Propylene-pentene copolymer (70: 30 average Molecule most s,ooo) (R&B-
155℃＞5lfii polyester resin
20 parts by weight The above materials are mixed and pulverized in a ball mill, melted and kneaded in a hot roll mill, cooled, coarsely pulverized in a hammer mill, and then finely pulverized in an air jet type pulverizer. The obtained fine powder was classified to produce a toner having an average particle size of about 13 to 15 μm. This toner's R&B
was 129°C.

A developer was prepared by mixing 4 parts of this toner with 96 parts by weight of an iron powder carrier having an average particle size of about 50 to 80 μm, and an electrostatic image formed by a conventional electrophotographic method was developed with this developer. After that, the toner image was transferred onto a transfer paper, and the fixing roller having a smooth surface made of Teflon (manufactured by DuPont) was used without supplying an offset prevention liquid to a temperature of 160±5 around the lower limit fixing temperature. The toner image was fused and fixed by pressure contact at .degree. When this operation was repeated for 100 sheets in a row and the winding around the fixing roller was observed, -
No coiling occurred during the rotation.

Comparative Example 7 Styrene-methacrylic acid copolymer (85:15) 80 parts by weight Nigrosine base EX 5 parts by weight Carbon black (#44) 5 parts by weight Propylene-acrylic acid copolymer (70: 30 Average molecular weight 5,000 ) (R&8-
165°C> 5 parts by weight Polyester resin 20 parts by weight The above material was treated in the same manner as in Example 1 to prepare a toner and use it as a sample. The R&B of this toner was measured and found to be 129°C.

When fixing was carried out under the same conditions as in Example 1, more than 50 sheets out of 100 were curled and jammed.

Example 8 Styrene-methacrylate acid copolymer (70:30
) 65 parts by weight Nigrosine Base EX (71 Rient Chemical) 3 parts by weight Phthalocyanine Blue 5 parts by weight Ethylene-propylene copolymer (20:80 average molecular weight e, ooo) (R&B
-140°C) 5 parts by weight polyester resin 35 parts by weight The above material was treated in the same manner as in Example 1 to prepare a toner and use it as a sample. The R&B of this toner was measured and found to be 117°C.

This toner was used as a fixing roller whose surface was made of silicone rubber, and the same operation as in Example 1 was performed except that the melting temperature was 145±5°C.
Regarding 00 sheets, wrapping around the fixing roller and jam were observed. As a result, not a single sheet jammed.

Comparative Example 8 Styrene-methacrylate acid copolymer (70:30
) 65 parts by weight Nigrosine base EX 3 parts by weight Phthalocyanine blue 5 parts by weight Propylene-butene copolymer (80:20 average molecular weight 5,000') (R&
B = 152°C) 5 parts by weight polyester resin
The above material was treated in the same manner as in Example 1 to prepare a toner, which was used as a sample. The R&B of this toner was measured and found to be 117°C.

When this toner was fixed under the same conditions as in Example 2 and jams were observed on 100 sheets, 30 or more sheets were jammed.

Effects The toner of the present invention does not wrap around the fixing roller or jam, even during fixing near the lower limit fixing temperature.

Further, if the fixing device has a mechanism such as a claw for forcibly separating the fixing roller and the transfer paper, the mechanism prevents the image from being exposed. Further, the A offset phenomenon does not occur.

Claims (1)

[Claims] In a toner containing a colorant, a binder resin, and a low molecular weight olefin polymer or copolymer, the ring and ball softening point of the toner is X°C, and the ring and ball softening point of the low molecular weight olefin is A toner for developing an electrostatic image, characterized in that Y°C satisfies the following relational expression. Y≦0.9X+40