JPH01112254A - Metallic toner composition - Google Patents

Abstract

PURPOSE:To form an image exhibiting a sharp metallic gloss by using a metallic toner composition containing a binder resin, thin flakes of a basic material successively coated with a black titanium oxide layer and a titanium oxide layer specified in thickness and a specified polyamide resin. CONSTITUTION:The metallic toner composition contains the thin flakes of the material successively coated with the black titanium oxide layer and the titanium oxide layer specified in film thickness, and the binder resin together with the polyamide resin having the structural units each represented by formula I and II in which m is an integer of >=8; n is an integer of >=2; X is >=8C aliphatic hydrocarbon residue; and p is a positive integer. This polyamide resin having the units of formula I is obtained by polymerizing >=9C lactam or aminocarboxylic acid, and the resin having the units of formula II is obtained by polymerizing >=2C alkylenediamine with >=10C alkylenedicarboxylic acid, thus permitting the obtained toner to exhibit a sharper and more metallic gloss as compared with the conventional metallic toners.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a metallic toner composition for developing electrostatic images formed in electrophotography, electrostatic printing, electrostatic recording, or the like.

(Prior art) Conventionally, in copying machines using electrophotography, charging,
The electrostatic charge image formed on the photoreceptor by exposure to light is developed with a powder toner containing a binder resin, a colorant, etc., and the developed toner image is transferred to a support such as a transfer paper, and then a heating roller or By fixing the toner image marked ``-'' on a support using a pressure roller, the electrostatic charge image ``1'' is visualized, and black or color toner is generally widely used as the powder toner.

On the other hand, in recent years, there has been a demand for toners for copying images having metallic tones in order to enhance decorativeness, but the above-mentioned conventional toners cannot meet such uses.

In order to meet the above requirements, we have developed toners containing metallic aluminum powder and various coloring agents, mica titanium made by covering fine mica powder with a thin film of titanium oxide, or pearl pigments made by adsorbing fine coloring particles on the surface of mica titanium. A toner that does this has been proposed.

However, the above-mentioned metallic aluminum powder has problems with handling and safety during toner production, and mica titanium and pearl pigments are easily affected by the color and surface condition of the support, so it is difficult to reproduce reproduced images with the desired metallic luster. The problem was that it was difficult to obtain. To achieve the above object, metallic toner compositions have previously been proposed which contain, together with a binder resin, a flaky material in which a flaky substrate is successively coated with a layer of black titanium oxide. (Patent Application No. 612,467 (Problems to be Solved by the Invention)) However, regarding metallic toner, there is a demand for images that exhibit a metallic color that is even clearer and has excellent decorative properties.Therefore, the object of the present invention is to To provide a toner exhibiting more vivid metallic gloss than conventional metallic toners.

(Means for Solving the Problems) The metallic toner composition of the present invention includes, together with a binder resin,
A polyamide resin having a structural unit represented by the following general formula [I] or [II] and a flaky substrate are sequentially coated with a black titanium oxide layer and a titanium oxide layer having a predetermined thickness. It is characterized by this.

(In the formula, m is an integer of 8 or more, n is an integer of 2 or more, X is an aliphatic hydrocarbon residue having 8 or more carbon atoms, and p is a positive integer.) (Function) Together with the binder resin, A metallic toner composition containing a flaky material in which a flaky substrate is sequentially coated with a black titanium oxide layer and a titanium oxide layer having a predetermined film thickness has a more vivid metallic luster than conventional mica titanium and pearl pigments. However, there is a strong demand for a toner that exhibits even more vivid metallic luster.

As a result of research on this point, the present inventors found that the olefin polymer added as an anti-offset agent
It has been discovered that due to the poor compatibility with the binder resin, the transparency of the obtained toner image deteriorates and the metallic gloss is inhibited.

Therefore, as a result of further research into offset inhibitors that have good compatibility with binder resins and can produce toners with excellent clarity and gloss, we found that the following formula (1) or (1'l) It has been found that the expressed polyamide resin has excellent compatibility with various binder resins and excellent transparency of toner images.

Moreover, since the polyamide resin has mold releasability, it has the effect of preventing the offset phenomenon.

A metalisotoner using this polyamide resin as an anti-offset agent in place of the olefin polymer was able to obtain a clear metallic luster.

(In the formula, m is an integer of 8 or more, n is an integer of 2 or more, X is an aliphatic hydrocarbon residue having 8 or more carbon atoms, and p is a positive integer.) Below, details of the present invention are shown. explain.

Examples of the binder resin used in the metallic toner composition of the present invention include olefins such as styrene polymers, acrylic polymers, styrene-acrylic copolymers, polyethylene, chlorinated polyethylene, polypropylene, and ionomers. Polymers, polyvinyl chloride, polyester, polyamide, polyurethane, epoxy resin, diallyl phthalate resin, silicone resin, ketone resin, polyvinyl butyral resin, phenol resin, rosin-modified phenol resin, xylene resin, rosin-modified maleic acid resin, rosin ester Examples include various polymers such as , petroleum resin, and the like.

Examples of unsaturated monomers used in the above-mentioned polymers include styrene, α-methylstyrene, 0-methylstyrene, p-
Styrenic monomers such as methylstyrene, p-methoxystyrene, p-chlorostyrene; acrylic acid, methyl acrylate, ethyl acrylate, -butyl acrylate,
Isobutyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate,
stearyl acrylate, cyclohexyl acrylate, phenyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, glycidyl acrylate, cicathylaminoethyl acrylate, acrylamide, acrylonitrile, methacrylic acid, methyl methacrylate, Ethyl methacrylate, methacrylic (gn-butyl, isobutyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, dodecyl methacrylate, Acrylic or methacrylic monomers such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, and diethylaminoethyl methacrylate; unsaturated monomers such as maleic acid, fumaric acid, crotonic acid, itaconic acid, or alkyl esters thereof Examples include carboxylic acid having a double bond or an alkyl ester thereof; olefinic monomers such as ethylene, propylene, butadiene; vinyl acetate; vinyl chloride; vinylidene chloride; vinylpyrrolidone; vinylnaphthalene, etc. The above monomers include: Used alone or in combination of two or more.

Among the above polymers, those containing styrene polymers, acrylic polymers, styrene-acrylic copolymers, polyesters, etc. as main components are preferred.

These polymers have a weight average molecular weight of 30,000 to 20
0,000, particularly preferably 50,000 to 15o, ooo, and may be used singly or in combination of two or more.

Among the above polymers, rosin esters, rosin-modified phenolic resins, rosin maleic acid resins, epoxy resins, polyesters, cellulose polymers, polyether resins, etc. are useful in improving the triboelectric properties of toner. It is.

Further, when the toner is a heat fixable toner, the above polymer has a softening point of 50 to 200°C, preferably a softening point of 70 to 200°C.
Those having a temperature of 170°C are preferred.

An important feature of the toner composition of the present invention is the use of a specific polyamide resin together with the binder resin.

That is, a polyamide resin having a structural unit represented by the following format (1) or (II) is used.

(In the formula, m is an integer of 8 or more, n is an integer of 2 or more, X is an aliphatic hydrocarbon residue having 8 or more carbon atoms, and p is a positive integer.) More specifically, the above- The polyamide resin having a structural unit represented by the formula CI) is a lactam or aminocarbon having 9 or more carbon atoms. The polyamide resin represented by form (1) is obtained by polymerizing an alkylene diamine having 2 or more carbon atoms and an alkylene dicarboxylic acid having 10 or more carbon atoms. be. Note that the polyamide resin may be one having the structural unit [I], C11), and may be a copolymer with other lactams, aminocarboxylic acids, alkylene diamines, aliphatic dicarboxylic acids, etc. .

Examples of the lactam and aminocarboxylic acid include laurolactam, aminononanoic acid, and ω-aminoundecanoic acid. Examples of the di-alkylene diamine include ethylenediamine, diethylenetriamine, triethylenetetramine, hexamethylenediamine, and pentamethylenediamine. Examples of alkylene dicarboxylic acids include sebacic acid, dodecane dicarboxylic acid, and dimer acid, which is a dimer of unsaturated fatty acids.

The polyamide resin having a structural unit represented by form [I] or (n) above may be 9-nylon, which is a polymer of aminononanoic acid, or 11, which is a polymer of ω-aminoundecanoic acid. - Nylon, 12-nylon, which is a ring-opening polymer of laurolactam, 6°10-nylon, 6.12-nylon, which is a polymer of hexamethylene diamine, sebacic acid, and dodecanedicarboxylic acid, and dimer with the above alkylene diamine. Polyamide resins which are polymers with acids are preferred. The above-mentioned polyamide resin has low hygroscopicity and, unlike conventional olefin polymers, has excellent transparency, sharpness, and mechanical strength of toner images.

The above polyamide resins may be used alone or in combination of two or more.

The above polyamide resin can be used in an appropriate amount depending on the binder resin and other additives used, but it is added in an amount of 1 to 20 parts by weight, particularly 5 to 10 parts by weight, based on 100 parts by weight of the binder resin. Preferably. If the content of the polyamide resin is less than 1 part by weight, the offset phenomenon cannot be sufficiently prevented, and if it exceeds 20 parts by weight, image unevenness such as thin white spots tends to occur, especially in solid areas.

Further, the toner of the present invention is characterized in that it contains the above-mentioned flaky substance in order to obtain metallic luster without being affected by the color or surface condition of the support such as copy paper. This flaky material has a sand-inch structure in cross section, in which a flaky substrate is sequentially coated with a black titanium oxide layer and a titanium oxide layer of a predetermined thickness. By adjusting the film thickness of the titanium oxide layer, the transmitted light of the light incident on the flaky material is absorbed by the black titanium oxide layer, and the reflected light that is multiple-reflected by the titanium oxide layer is absorbed by the black titanium oxide layer. Due to interference, the titanium oxide layer exhibits a unique interference color and metallic luster depending on its thickness.

In other words, the peak of the reflectance is sharp and clear interference color and metallic luster are produced. Especially since the titanium oxide layer is made of titanium oxide with a large refractive index.

The interference color and metallic color become even stronger.

The relationship between the primary interference color of the flaky material and the thickness of the titanium oxide layer is as follows.

(No description on this page below) The above-mentioned flaky substance may be any flaky substance, such as barium sulfate, layered silicate, layered aluminosilicate, etc., but may include white lead hexagonal plate crystals, guanine crystals, fish scales, and especially mica are preferred. In addition, the aspect ratio, which indicates the ratio between the thickness and length of the substrate, is 1:10 to 1:
It is preferably in the range of about 50, and mica is also excellent in this respect. Note that the flaky material has an average particle size of 5
Preferably, it has a diameter of ~20 μm.

Further, the black titanium oxide layer covering the flaky substrate is
It is sufficient that the film has a thickness that absorbs the light transmitted through the titanium oxide layer among the light incident on the flaky substrate. The black titanium oxide layer is obtained, for example, by reducing titanium oxide at a high temperature, and has the -format Ti, O□. Among the lower titanium oxides represented by -1, it has an oxidation degree of about n=2 to 5.

The thickness of the titanium oxide layer as the outermost layer can be adjusted as appropriate depending on the degree of metallic gloss and interference color required, but the ratio of the titanium oxide layer in the flaky material is
10 to 60% by weight, especially 30 to 50% by weight is preferred. If the amount of titanium oxide is outside the above range, it will be difficult to obtain the optical thickness and geometric thickness necessary to obtain interference colors.

The flaky material has a small color difference and a high hiding rate compared to conventional pearl pigments and the like. That is, while conventional golden pearl pigments show a color difference of about 16.6 according to Hunter's equation, when mica is used as the flaky substrate, the flaky material has a color difference of about 2.1. In addition, since the flaky material is formed of a flaky substrate, a black titanium oxide layer, and a titanium oxide layer, it not only has no risk of dust explosion, but also has excellent light resistance and heat resistance. It is extremely stable against corona discharge, ozone, etc., and is suitable as an I-ner material.

The above-mentioned flaky substance may have an appropriate particle size within a range that does not impair the characteristics of the toner, but is preferably 1 to 40 μm, particularly 5 μm
Those having an average particle size of ~30 μm are preferred. If the particle size of the flaky substance is less than 1 μm, the metallic luster tends to be lost, and if it exceeds 40 μm, the flaky substance is exposed on the surface of the resulting toner, resulting in deterioration of toner properties or damage to the toner. It becomes difficult to produce particles with a suitable particle size.

The flaky substance may be present in an amount of 1 to 40% by weight, especially 5% by weight in the toner.
Preferably, the content is 30% by weight. When the amount of flaky material is less than 1% by weight, it is difficult to obtain a metallic color tone, and when it exceeds 40% by weight, it becomes economically disadvantageous and it becomes difficult to obtain a homogeneous toner.

The metallic toner of the present invention basically has the above composition, but in order to obtain vivid coloring, it is preferable to use a coloring agent together with the flaky material.

As the coloring agent, for example, chrome yellow (C,1
, No. 14090), Hansa Yellow (C, 1,
No.

11660.11680 etc.), Suren Yellow G (C,
1.No.

70600), Quinoline Yellow (C,1,No,
47005), Permanent Orange GTR (C
, 1, No. 12305), Pyrazolone Orange (
C, 1, No, 21110), Watch Young Red (C, 1, No, 15865), Permanent Red (C, 1, No, 12310), Brilliant Carmine 3B (C, 1, No, 16105), Brilliant Tocarmine 6B (C, 1, No. 15850), DuPont Oil Red (C, 1, No.

26105 >, pyrazo 1m) 7 L/ 7 de (C,
1, No. 21120), Lysol Resodo (C, 1,
No. 15630), Rhodamine B Lake (C, 1,
No. 45170), Lake Red C (C, I.

No, 15585), Rose Bengano C, 1, No
, 45435), Aniline Blue (C, I, No, 5
0405), Ultramarine Blue (C, 1, No.
77103), Calco Oil Blue (C, 1, No.
azoec Blue 3), methylene blue chloride (C, 1, No, 52015), phthalocyanine blue (C, 1, No, 74160), phthalocyanine green (C, 1, No, 74260), malachide green oxalate (C, T.No.42000
) etc., or C,1,5olvent Yellow
60, C, 1,5olvent Red 27, C,
Examples include oil-soluble dyes such as 1,5olvent Blue35. It is preferable that these colorants have transparency so that the color development becomes clear and the above-mentioned metallic luster is not inhibited.

In addition, these colorants may be used alone or in a mixture of two or more, and in an amount that provides sufficient image density, for example, 1 to 2 or more.
30% by weight, preferably 2-20% by weight.

Further, in order to control the charge of the metallic toner, the toner preferably contains a charge control agent as another additive. Examples of the charge control agent include oil-soluble dyes such as nigrosine dye (C, 1, No., 50415B, oil blank (C91, No., 26150), and Subiron Burasoku), naphthenic acid, salicylic acid, octylic acid, fatty acids, and resin acids. manganese, iron, cobalt, lead,
Examples include metal soaps that are metal salts of zinc, cerium, calcium, nickel, etc., metal-containing azo dyes, pyrimidine compounds, alkylsalicylic acid metal chelates, etc., and they are contained in an amount of 0.1 to 10% by weight per toner. preferable.

Further, in order to impart conductivity to the toner, the toner may contain various conductivity imparting agents.

Note that, in order to protect the photoreceptor, a fatty acid metal salt may be added to the metallic toner. The fatty acids in the fatty acid metal salts include saturated or unsaturated fatty acids having 8 to 36 carbon atoms, such as caprylic acid, capric acid, undecylic acid,
Lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, behenic acid, lignoceric acid, cerotic acid, montanic acid, oleic acid, elaidic acid, linoleic acid, linolic acid, erucic acid, lysyllic acid, dihydroxystearic acid, cyclic Among fatty acids, tribasic acids, and the above-mentioned unsaturated fatty acids, saturated fatty acids, particularly stearic acid, are preferred.

In addition, the metals of the fatty acid metal salts include zinc, lead, iron, copper, tin, cadmium, aluminum, calcium,
Examples include various metals such as magnesium, nickel, cobalt, manganese, lithium, and barium.

The fatty acid metal salt is added in an amount of 0.01 to 10 parts by weight per 100 parts by weight of the powder toner.

Furthermore, in order to improve the fluidity of the toner, a fluidity imparting agent such as hydrophobic colloidal silica or alumina is added to the above metallic toner.

preferable. The above fluidity imparting agent has an average particle size of 5 to 100 m.
μ, especially those having a μ of 10 to 30 mμ are preferable, specifically, the product name “Aerosil R9” manufactured by Nippon Aerosil Co.
Examples include aluminum oxide CJ (average particle size 20 mμ) and 72J (average particle size 16 mμ). These fluidity imparting agents are added in an amount of 0.01 to 10 parts by weight per 100 parts by weight of the powder toner.

Further, the surface of the metallic toner may be treated with a silane coupling agent, silicone, or a fluorine compound. Furthermore, the above-mentioned powder toner may optionally include:
In order to improve the fluidity of the toner, the corners and the like of the toner may be smoothed by heat treatment.

The above metallic toner has an average particle size of 5 to 50 μm and is particularly suitable as a two-component toner. When used as a two-component toner, it is mixed with a carrier such as iron powder or glass beads to form a developer. The above-mentioned carrier may be an uncoated carrier such as glass beads or oxidized or unoxidized iron powder, or a magnetic material such as iron, nickel, cobalt, or ferrite, and a polymer such as acrylic polymer, fluorine polymer, or polyester. The coating covered by the coalescence
, a ring carrier is used and usually has a particle size of 50 to 2000 μm. Further, when a developer consisting of the above toner and carrier is used, the toner is usually used in an amount of 2 to 10% by weight.

Below, one method for producing the above-mentioned flaky material will be explained.

First, in a slurry containing a flaky substrate, (11Ti
alkaline conditioned hydrolysis of a soluble titanium compound such as C14 to deposit Ti(OH)4 onto the flaky substrate and heating to coat the substrate with TiO□;
(Heating in the presence of 21T i OS Oa and coating with the generated TiO2. Next, a metal titanium layer is mixed and heated to reduce, or by heating and reducing in a hydrogen atmosphere, a black TiOz layer is formed. Then, the flaky material can be manufactured by applying the method (1) or (2) above again to the black TiO□ layer of the substrate to form a TiO2 layer with a desired thickness. Yes, you can.
The thickness of the outermost T i 02 layer can be adjusted by changing the ratio of the flaky substrate to the soluble titanium compound, reaction time, and other conditions.

Next, the method for manufacturing the metallic toner of the present invention will be briefly explained.

First, binder resin, flaky material, coloring agent, polyamide resin, etc. are mixed, cross-dispersed using a heated kneader such as a hot roll or an extruder, and then mixed and dispersed using a pulverizer such as a hammer mill or die'7 mill. In addition to pulverizing, the particles are classified using a classifier in order to obtain a predetermined particle size. In this method, care must be taken to prevent the flaky material from being crushed into fine particles during cross-dispersion and crushing.

Alternatively, it can also be produced by spray drying, in which the binder resin is dissolved in an appropriate solvent, the flaky material, etc. is dispersed in this binder resin solution, and the dispersion is spray-dried to granulate it to a predetermined particle size. be able to. This method is advantageous in that the flaky material is not destroyed.

Furthermore, in addition to flaky materials, it can also be produced by a polymerization method in which suspension or emulsion polymerization is performed using a polymerizable dispersion containing the monomer.

In addition, the metallic toner obtained as above,
When mixing with the carrier or, if desired, adding the fatty acid metal salt, an appropriate mixer such as a ball mill or type mixer is used.

The metallic toner of the present invention is developed by a conventionally known developing method, such as a bristle brush developing method, a magnetic brush developing method, or a cascade developing method.

(Example) Developer 1 (Invention) Styrene-acrylic copolymer (XPA-525, trade name of Mitsui Toatsu Kogyo Co., Ltd.) 100 parts by weight, optical thickness 310 nm
an outermost titanium oxide layer having (40 to 45 parts by weight)
15 parts by weight of a flaky substance formed with 15 parts by weight of a polyamide resin having a 12-nylon structural unit as an offset inhibitor (X4434, trade name manufactured by Daicel-Hüls) 3
A metallic toner was prepared using 3 parts by weight of a charge control agent (Bontron E-82, trade name manufactured by Oriental Chemical Industry Co., Ltd.). That is, a mixture of the above materials was dissolved and dispersed in 300 parts by weight of toluene using a homomixer, and then a spherical metallic toner was obtained by spray drying.

This powder was classified to obtain a metallic toner having a particle size of 5 to 50 μm.

Next, based on 100 parts by weight of the above metallic toner,
Add and mix 0.3 parts by weight of hydrophobic silica fine particles (Aerosil R972, trade name manufactured by Nippon Aerosil Co., Ltd.), and add 25 g of this mixture and ferrite carrier (F-141-153).
0, trade name manufactured by Nippon Tetsuko Co., Ltd.) were mixed to prepare a developer.

Developer 2 (Comparative Example 1) A developer was prepared in the same manner as in Example 1, except that polyolefin (Viscol 550P, manufactured by Sanyo Chemical Co., Ltd.) was used in place of the polyamide resin (X4434) of Example 1 above.

Developer 3 (Comparative Example 2) A developer was prepared in the same manner as in Example 1, except that 15 parts by weight of titanium mica, which exhibits a blue interference color, was used in place of the flaky material of Comparative Example 2.

When these developers were put into a copying machine DC-111 (manufactured by Sanda Kogyo) and copied, Example I produced an image with a more vivid blue metallic luster than that of Comparative Example 1, and a large number of copies were made. However, the image characteristics and toner and developer characteristics did not deteriorate.

Further, even when continuous copying was performed, no off-center development of toner on the heat roller occurred. When the image was then copied onto yellow copy paper using the same developer, it exhibited the same metallic luster as above without being affected by the copy paper.

When the image of Comparative Example 2 was copied onto yellow copy paper, the image exhibited a greenish metallic luster.

(Effects of the Invention) As described above, according to Metallics 1 to 2 of the present invention,
Together with the binder resin, a flaky substrate is sequentially coated with a black titanium oxide layer, a titanium oxide layer with a predetermined film thickness, and a specific polyamide that has mold releasability and is highly compatible with the binder resin. Since it contains a resin, it is possible to form an image with a clear metallic luster without being affected by the color or surface condition of the support.

Patent applicant: Mita Kogyo Co., Ltd.

Claims (6)

[Claims] (1) The toner for developing an electrostatic image is composed of a binder resin, a polyamide resin having a structural unit represented by the following general formula [I] or [II] as a release agent, and a flaky substrate that is black oxidized. A metallic toner composition comprising a flaky material sequentially coated with a titanium layer and a titanium oxide layer having a predetermined thickness. ▲There are mathematical formulas, chemical formulas, tables, etc.▼[I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼[II] (In the formula, m is an integer of 8 or more, n is an integer of 2 or more, and X is a carbon number of 8 or more aliphatic hydrocarbon residues, p is a positive integer, respectively.) (2) The metallic toner composition according to claim 1, wherein the toner contains a colorant. (3) The ratio of the titanium oxide layer of the flaky material is 10 to 60
% by weight of the metallic toner composition according to claim 1. (4) The metallic toner composition according to claim 1, wherein the content of the flaky substance is 1 to 40% by weight. (5) The metallic toner composition according to claim 1, wherein the polyamide resin is 12-nylon. (6) The metallic toner composition according to claim 1 or 5, wherein the content of the polyamide resin is 1 to 20 parts by weight based on 100 parts by weight of the binder resin.