JPH0713756B2 - Toner composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a toner composition used in electrophotography, electrostatic printing, magnetic recording and the like.

[Prior Art] An electrophotographic method forms an electrostatic latent image by utilizing the properties of a photoconductor such as cadmium sulfide, polyvinylcarbazole, selenium, and zinc oxide. For example, it is uniform on a photoconductor layer. To form an electrostatic latent image by imagewise exposure, and then develop with toner powder having a polarity opposite to that of the electrostatic latent image, and further transfer to a transfer sheet if necessary. It is a method of fixing.

The electronic printing method is a method in which a charged powder toner is guided and fixed onto a recording material using an electric field to print as proposed in Japanese Patent Publication No. 42-14342.

The electrostatic recording method is a method in which an electric charge is applied in the form of an image on a dielectric layer, and charged toner powder is adhered to and fixed to the dielectric layer. Similarly, the magnetic printing method forms a magnetic latent image on a recording material. Then, this is developed with toner powder containing a magnetic material, transferred to a transfer material, and fixed.

Toner used in the above method, to prepare a thermoplastic or pressure plastic resin, for coloring, carbon black or red, a dye or pigment such as blue are mixed, to a magnetic toner, Fe ₃ O Magnetic powders such as ₄ , Ni and Co are further mixed. In order to obtain a charged toner, an organic substance (mostly a dye) or an inorganic substance called a charge control agent, or a resin having a cationic functional group such as an amino group or an anionic functional group such as a halogen group is further added. A substance having a strong charge, such as a resin, is added. Furthermore, when adopting a method of applying fixing energy to the toner in the fixing method (for example, heat roll fixing or pressure roll fixing), a releasing material is added to prevent offset of the toner to the device. Or when the toner is pulled between the device such as paper and the device, the binder resin of the toner has a cross-linking structure so that the toner does not remain on the device side, making the toner tenacious and difficult to spread. Things like that are done. In addition, the toner is required to have its original fixability to the object to be fixed, developability to the latent image, and transferability from the latent image surface to the object to be fixed. It is desired not to deteriorate.

In order to satisfy the above requirements, it is desired that each toner particle has no individuality. If the added magnetic substance or charge control agent is unevenly distributed among the particles, the one having good developability will be consumed first, and as a result, the image will be greatly changed in the direction of deterioration. Further, there is a difference in charging property between the particles, and in the case of an electrostatic latent image, background fogging may occur due to charged toner, which is contrary to the requirement, and electrostatic aggregation due to charged particles may occur. Further, if the developing property is poor in the first place, it tends to cause problems such as scattering, because it is out of control in the developing device.

Regarding the problem of dispersion, there is a problem that the resin used for blending has poor compatibility, or a substance having a low molecular weight causes migration and is accumulated on the surface, or contaminates an apparatus or the like.

In the case of inorganic powder, it is mostly hydrophilic, and it is possible to organicize the surface with various coupling agents to improve compatibility with the resin or to use a surfactant to make the resin easily wettable. Coupling agents and surfactants that are not adsorbed on the inorganic powder make the humidity characteristics of the toner sensitive. Further, it is effective in kneading resins with each other, particularly in dispersing a release agent having low surface energy such as polyethylene and polypropylene.

[Problems to be Solved by the Invention] The present invention has been made to provide a toner composition which solves the above-described problems relating to surface chemistry.

A further object of the present invention is to provide a toner composition which is excellent in versatility and in which various properties of the toner can be easily controlled.

[Means and Actions for Solving Problems] Specifically, the present invention provides the following formula (I): [In the formula, R represents an alkyl group having 4 to 45 carbon atoms. ] The α-olefin represented by the following formula (II) A copolymer (i) with maleic anhydride or a derivative thereof represented by: or the following formula (III) [In the formula, R represents an alkyl group having 4 to 45 carbon atoms. ] Toner particles containing a polymer (ii) or a copolymer (iii) of an alkenyl succinic anhydride or a derivative thereof (provided that the copolymer (i) and the polymer (ii) are provided on a core substance). Or a microcapsule toner particle having the above-mentioned copolymer (iii) together with a shell substance).

The polymers (i), (ii) and (iii) will be described below.

For example, those directly connected to the ethylene skeleton include the following structural units (A) and (B): (Wherein R represents an alkyl group) as an essential structural unit in the polymer chain is an α-olefin-maleic anhydride copolymer.

This copolymer further has a structural unit (C): May be included.

As the pendant type, for example, the structural unit (D): There is a polyalkenyl succinic anhydride polymer having as an essential structural unit in the polymer chain [This polymer may further contain the above structural unit (C) in the polymer chain. ].

The alkyl group portion has hydrophobicity and low surface energy, while the maleic acid portion has hydrophilicity and exhibits strong polarity.
It is highly reactive with hydroxyl groups, amino groups and glycidyl groups.

The main point of the present invention is that both the alkyl group and the acid anhydride are contained in the same polymer chain, which exhibits high surface activity and satisfies various requirements as a toner.

The chain length of the alkyl moiety is between C _{4 and} C ₄₅ , and C ₁₀ to C.
It is preferable that ₂₈ is the main one in terms of surface activity. The hydrophobicity becomes stronger as the alkyl chain length increases, and the effect of the acid anhydride moiety becomes more pronounced as the alkyl chain length becomes shorter. When the range of chain length is widened, intermediate properties of the two appear as a whole, but when viewed microscopically, it becomes a mixture of a hydrophilic part and a hydrophobic part.

The acid anhydride portion easily opens when left in the air for a long time or exposed to hot water, but also easily closes when heated. The ring-closure product easily reacts with an aluminum compound, an epoxy compound, an alcohol, or a basic compound to introduce a crosslinked structure or a charge controllable functional group into the binding resin.

A combination of a long-chain alkyl group and an acid anhydride shows sufficient performance, but it is slightly soft and brittle, so other styrene,
Strengthening by multi-copolymerization with vinyl monomers such as acrylic acid ester, methacrylic acid ester, etc., and further compatibility with styrene resin, which is another component of the binder resin, or acrylate resin, methacrylic acid ester resin Can be improved.

The copolymerization of α-olefin and maleic anhydride has a high alternating copolymerization property, and the copolymerization ratio is easily around 1: 1. Although generally good performance is obtained at this copolymerization ratio, it is also possible to shift the copolymerization ratio depending on whether the binder resin to be mixed is nonpolar or strongly polar.

The weight average molecular weight of the copolymer having a long chain alkylene and an acid anhydride or its derivative unit in the polymer chain in the present invention is preferably 3,000 to 100,000.

The amount of the copolymer having a long-chain alkylene and an acid anhydride or a derivative thereof in the polymer chain in the whole toner is
In the range of 1 to 30% by weight, sufficient performance is exhibited, and when forming a multi-component copolymer with another monomer, the copolymerization ratio can be determined in consideration of this range.

As the resin used in combination with the above copolymer in the toner composition of the present invention, generally known resins can be used, and examples thereof include polystyrene, poly-p-chlorostyrene, polyvinyltoluene, styrene-butadiene copolymer, and styrene. -Acrylic acid copolymers, polymers or copolymers of styrene or its substitution products such as styrene-methacrylic acid copolymers; epoxy resins, polyester resins, acrylic resins, acrylonitrile resins, xylene resins,
Polyurethane resin, polyurea resin, polyamide resin,
Ionomer resin, furan resin, ketone resin, terpene resin, phenol-modified terpene resin, rosin, rosin-modified pentaerythritol ester, natural resin-modified phenol resin, coumarone indene resin, alicyclic hydrocarbon resin, petroleum resin, cellulose phthalate acetate , Starch graft polymer, polyvinyl butyral, polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl pyridine, polyvinylidene chloride, polyvinylidene fluoride, polyvinyl imidazole, polypyrrole, chlorinated paraffin, wax, fatty acid ester, polyethylene, polypropylene, etc., alone or in combination. Can be used.

Known dyes and pigments can be used as the colorant to be combined with the toner composition of the present invention, for example, various carbon blacks, aniline blacks, naphthol yellows, molybdenum oranges, rhodamine lakes, alizarin lakes, methyl violet lakes, phthalocyanine blues, Examples include nigrosine methylene blue, rose bengal, quinoline yellow, and the like.

The magnetic substance to be combined with the toner composition of the present invention is a ferromagnetic element such as iron, cobalt, nickel or manganese, and an alloy or compound containing magnetite, ferrite or the like containing these.

Further, as the releasing material to be combined with the toner composition of the present invention, a general releasing agent can be used, for example, low molecular weight polyethylene wax, low molecular weight polypropylene, paraffin wax, fatty acid, and its ester or metal soap. , Fatty alcohols, polyhydric alcohols, and their metal salts, chlorides, fluorides, amides, bisamides, and the like.

EXAMPLES Next, the present invention will be described with reference to examples.

Example 1 100 parts by weight of styrene-butyl methacrylate (weight ratio 7: 3) copolymer, 60 parts by weight of magnetite, 6 parts by weight of polyethylene wax, 1 part by weight of nigrosine, and the α-olefin (C ₁₈ ) -maleic anhydride of the present invention. Acid copolymer (copolymerization ratio
1: 1, molecular weight 50,000) 10 parts by weight are mixed and rolled.
Melt and knead at 140 ° C. After cooling, coarse pulverization is performed with a hammer mill and then fine pulverization is performed with a jet pulverizer. Then, classification was performed using an air classifier to obtain fine powder having a particle size of approximately 5 to 20 μm. Colloidal silica 0.4 is added to 100 parts by weight of this fine powder.
A part by weight was added to obtain a toner. When this toner was applied to a commercially available copying machine (trade name: Mini Copier, PC-20, manufactured by Canon) and an image was printed, a clear image free from fog was obtained. There was no offset of the toner on the heating roll of the fixing device, and the image was the same as the initial image even after continuous printing of 5000 sheets. The image density was high even in a high humidity environment of 35 ° C and 90%.

Comparative Example 1 A toner was prepared in the same manner as in Example 1 except that the α-olefin-maleic anhydride copolymer was not included. In the initial stage, an image similar to that of Example 1 was obtained, and no offset of the toner to the fixing roller was observed, but when images were continuously printed, background fog was seriously observed on the 200th to 300th sheets. The image density was decreased. Although the durability was improved when the weight of polyethylene wax was reduced to 2 parts, toner offset to the fixing roller began to be seen, and the part that could not be wiped off with the cleaning pad eventually became stains on the fixed image again. It came to be offset.

Example 2 According to the method of Example 1, when polyethylene wax was removed and melt-kneading was performed, and 5 parts by weight of bisphenol A was added on the way, the viscosity was increased and the composition became sticky. This cooled product was finely pulverized in the same manner as in Example 1 to obtain a toner.

When images were printed in the same manner as in Example 1, a clear image was obtained. There was no toner offset to the fixing roller, and the image was the same as the initial image after printing 5,000 sheets.

When this toner was embedded in an epoxy resin and sliced and the dispersion of the magnetic substance was observed with a transmission electron microscope, it was found to be uniformly dispersed in primary particles of 0.1 to 0.2 μm.

Comparative Example 2 10 parts by weight of a styrene-butadiene copolymer (copolymerization ratio 5: 5) was used in place of the α-olefin-maleic anhydride and bisphenol A of Example 2, but the compatibility between the resins was poor. , The toner turned gray. Although the effect was observed on the offset of the toner to the fixing roller, the dispersion of the magnetic material was poor, and many fine powders that did not contain the magnetic material were formed, forming aggregates.

Example 3 Low molecular weight polyethylene wax 100 having a molecular weight of 2000 to 3000
70 parts by weight of magnetite, 70 parts by weight of magnetite, α-olefin (C ₃₀ ) -maleic anhydride copolymer of the present invention (copolymerization ratio 1: 1.
2, molecular weight 10,000) 5 parts by weight, and 0.05 parts by weight of silicone oil having an amino group at the end are mixed, and the mixture is rolled.
Melt kneading was carried out at 120 ° C., and a toner was prepared in the same manner as in Example 1.

This toner shows a positive charge of +7.5 μc / g, and replaces the CdS photoconductor of a commercial copying machine (trade name, NP-120, made by Canon) with an OPC photoconductor to put a negative electrostatic latent image on it. When the image was put into a modified machine and imaged, a clear image without fog was obtained. The offset of the toner to the pressure fixing roller was extremely small. The toner was agitated in the developing unit so that the toner was hardly consumed through the 10,000-page blank original, but the image was the same as the initial one without deterioration of the fluidity. The image density was high even in a high humidity environment of 35 ° C and 90%.

Example 4 The silicone oil having an amino group at the end of Example 3 was added.
The same procedure as in Example 3 was repeated except that the amount was changed to 0.2 part by weight. This toner showed a positive charge of +15.2 μc / g. When images were printed in the same manner as in Example 3, a clear image was obtained.

The amount of toner offset to the fixing roller was further reduced.

Comparative Example 3 A toner was prepared in the same manner as in Example 4 except that the α-olefin-maleic anhydride copolymer was not included. The toner showed almost no positive charge, and the image was very fogged.

Example 5 70 parts by weight of carnauba wax and 30 parts by weight of polyethylene wax were mixed with 5 parts by weight of phthalocyanine, melted and dispersed / suspended in warm water at 95 ° C. to granulate spherical particles, and rapidly cooled to 5 Fine particles of 20 μm were obtained. MEK10 was added with 10 parts by weight of α-olefin (C _16-18 ) -maleic anhydride-styrene terpolymer of the present invention (copolymerization ratio 10:10:80, molecular weight 46,000).
Disperse the above fine particles in a solution dissolved in 00 parts by weight,
It was spray-dried under reduced pressure to obtain highly fluid particles. When the surface was observed with a scanning electron microscope, it was completely covered with the terpolymer. 10 parts by weight of the particles were mixed with 10 parts by weight of iron powder, and the particles were developed by sprinkling them on an electrostatic recording paper carrying a positive charge image, and a beautiful blue image was obtained.

Comparative Example 4 The procedure of Example 5 was repeated except that a styrene resin was used instead of the α-olefin-maleic anhydride-styrene terpolymer. While the obtained particles had many agglomerates, the surface of the particles was observed with a scanning electron microscope to find that the styrene resin was in the form of drops and was not sufficiently covered.

Example 6 alpha-olefin (C ₃₀₎ - In addition to the maleic anhydride copolymer, alpha-olefin (C ₃₀₎ - alkenylsuccinic anhydride copolymer (copolymerization ratio of 1: 1, molecular weight 7,500) to use a Was performed in the same manner as in Example 3, except that

This toner showed a positive chargeability of +7.0 μc / g. When images were printed in the same manner as in Example 3, as in Example 3, a clear image without fog was obtained, and the offset of the toner to the pressure fixing roller was very small, and the environment was high. No deterioration phenomenon was observed.

[Advantages of the Invention] As described above, the toner composition containing the long-chain alkylene of the present invention and the acid anhydride or the derivative thereof has excellent surface activity and manageable reactivity, and has a wide range. It has general versatility as a material of the above toner and gives the toner excellent performance.

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Yasuhide Goseki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Junichi Kurimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Kya Non-Incorporated (72) Inventor Toshiaki Nakahara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Toshiyuki Ochi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Naoyuki Ushiyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masuo Yamazaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Invention Satoru Wakamiya 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-60-69659 (JP, A) JP-B 4-755 01 (JP, B2)

Claims (2)

[Claims] 1. The following formula (I) [In the formula, R represents an alkyl group having 4 to 45 carbon atoms. ] The α-olefin represented by the following formula (II) A copolymer (i) with maleic anhydride or a derivative thereof represented by: or the following formula (III) [In the formula, R represents an alkyl group having 4 to 45 carbon atoms. ] Toner particles containing the polymer (ii) or copolymer (iii) of alkenyl succinic anhydride or a derivative thereof (provided that the copolymer (i) and the polymer (ii) are provided on the core substance). Or a microcapsule toner particle containing the copolymer (iii) together with a shell substance). 2. The toner composition according to claim 1, wherein R is an alkyl group having 10 to 28 carbon atoms.