JPS62276564A - Encapsulated toner for magnetography - Google Patents

Abstract

PURPOSE:To enhance fixability, to reduce fixing pressure, and to eliminate most of gloss of a copied image by incorporating a specified binder into a core material. CONSTITUTION:The encapsulated toner is composed of (1) the core material containing a polymer, a solvent having a melting point of >=150 deg.C and capable of dissolving or swelling said polymer, an organic liquid having a melting point of 100-250 deg.C and substantially incapable of dissolving or swelling said polymer, and magnetic particles in an amount of 10-60wt% of the total weight of the toner, and (2) outer shells surrounding the core material, thus permitting the obtained encapsulated toner for use in magnetography to be enhanced in fixability comparable with heat fixing and freed of most of gloss of the copied image.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of the Invention] The present invention relates to a magnetogelaphy that is used to convert a latent image formed using the principle of magnetic recording into a visible image. This invention relates to capsule toner.

[Background of the invention]

Heat fixing and pressure fixing are known as methods for fixing toner images in magnetography recording systems. Conventional heat-fixing toners are fixed by heating the resin, wax, etc. constituting the toner to 100-200'C and melting them. Pressure fixing toner includes:
A relatively short and easily deformable resin is used, and 300-≠0
It was fixed at a pressure as high as 4/rn2. Pressure fixing has advantages such as it consumes far less electricity than heat fixing, and does not cause paper jams or paper burns. It has the disadvantage of being too shiny.

[Purpose of the invention]

The present invention is a pressure fixing toner that consumes an order of magnitude less power and eliminates the need to worry about paper burning due to paper jams.The present invention is a capsule for magnetography that has fixing properties as good as heat fixation and does not produce glossy copies. The goal is to provide toner.

[Summary of the invention]

The present invention relates to a polymer, a solvent with a boiling point of iro 0c or higher that can dissolve or swell the polymer, and a boiling point of 100-2 that does not substantially dissolve or swell the polymer.
! A core material containing a mixture containing an organic liquid of 0 'C and magnetic particles, and an outer shell formed around the core material, the magnetic particles containing 70 to 60% by weight of the total weight. This capsule toner for magnetography is characterized by:

〔Effect of the invention〕

In addition, the capsule toner of the present invention includes a polymer in the core material, a boiling point at which the polymer can be dissolved or swollen/J-0
A high boiling point solvent of 0 C or more and a boiling point of 100 to 100°C that does not substantially dissolve or swell the polymer.
(Since it contains a binder containing an organic liquid within the range of 1', it has excellent fixing properties and the fixing pressure can be
o o Since it can be reduced to about K9/cm2, there is almost no gloss in the copied image.

[Detailed description of the invention]

The capsule toner of the present invention has a basic structure consisting of a core material and an outer shell formed around the core material.

The core substance of the capsule toner of the present invention has a yeast-like appearance,
A binder consisting of a polymer and an oily solvent and Ki magnetic particles are included.

Among the components constituting the core material of the capsule toner of the present invention, there is no particular restriction on the polymer that is a component of the binder. Examples of polymers contained as core materials include polyolefins, olefin copolymers, styrene resins, styrene-butadiene copolymers, epoxy resins, polyesters, rubbers, polyvinylpyrrolidone, polyamides, coumaron-indene copolymers, and methyl. Vinyl ether/maleic anhydride copolymer, amine resin, polyurethane, polyurea, homopolymer or copolymer of acrylic acid ester, homopolymer of methacrylic acid ester are also available.
-〈ke copolymer-acrylic acid 71-copolymer oligomer with long-chain alkyl methacrylate, polyvinyl acetate, polyvinyl chloride, etc., and the core material of the capsule toner of the present invention may contain these alone or in a mixed state. It may be contained in any of the following states.

Particularly preferred as the binder polymer are homopolymers or copolymers of acrylic esters, homopolymers or copolymers of methacrylic esters, or styrene-butadiene copolymers.

The oily solvent that is a component of the binder has a boiling point that can dissolve or swell the above polymer.
or higher boiling point solvents (hereinafter simply referred to as high boiling point solvents) and organic liquids (hereinafter simply referred to as non-intoxicating (also called decomposable organic liquids) are used in combination.

Examples of high-boiling solvents include phthalate esters (e.g., diethyl phthalate, dibutyl phthalate); aliphatic dicarboxylic acid esters (e.g., diethyl malonate, dimethyl oxalate); phosphate esters (e.g., tricresyl phosphate, tricresyl phosphate); citric acid esters (e.g., 0-acetyl triethyl citrate, triphthyl citrate); benzoic acid esters (e.g., butyl benzoate, hexyl benzoate); fatty acid esters (e.g., hexadecyl Myristate, dioctyl adihate): Alkylnaphthalenes e.g., methylnaphthalene, dimethylnaphthalene, monoisopropylnaphthalene, diisopropylnaphthalene): Alkyldiphenyl ethers (e.g., 0-1m-1p-methyldiphenyl ether); Higher fatty acids or aromas Amide compounds of group sulfonic acids (e.g., N,N-dimethylrafuramide, N-butylbenzene sulfo/amide); trimellitic acid esters (e.g., trioctyl trimellitate) and diarylalkanes (e.g., dimethylphenyl Examples include diarylmethane such as phenylmethane, /-phenyl-l-methylphenylethane, i-dimethylphenyl-/-phenylethane, diarylethane such as /-ethylphenyl-/-phenylethanato), and the present invention The core substance of the capsule toner may contain these substances alone or in a mixed state.

Examples of non-commonly digestible organic liquids include 1,2-roughin hydrocarbons, naphthenic hydrocarbons, and organic liquid mixtures containing these as main components. Examples suitable for use as an insoluble organic liquid to be included in the core material of the present invention include boiling point ranges (initial boiling point to soft point) of /! r
7g rough-in hydrocarbon (e.g. l5op) at ~777°C
ar G, product name, manufactured by Exxon Chemical, hereinafter the same),
Paraffinic hydrocarbons with a boiling point range of /7 hiro~/l'0C (e.g. l5opar H), boiling point range lll-2
100C paraffinic hydrocarbons (e.g. l5opar
L), paraffinic hydrocarbons with a boiling point range of 207 to 2 roo (e.g. 15opar M), a boiling point range of /12
~97°C naphthenic hydrocarbons (e.g. 5HELLS
QL-Dao, product name, manufactured by Shell Chemical ■, hereinafter the same),
Naphthenic hydrocarbons with a boiling point range of /rr to 220'C (
Example, 5HELLSQL -D A O) The boiling point range is IP! ~2! / 0C Nosu 7 ten-based hydrocarbons (e.g. 5
HELLSQL-D70).

The insoluble organic liquid can be mixed with the above-mentioned high boiling point solvent in any ratio, but generally the weight ratio of high boiling point solvent/insoluble organic liquid is 2//~//? It is preferable to mix within this range.

A binder is a composition that includes a polymer, a high boiling solvent, and a non-soluble organic liquid.

The mixing ratio of [Polymer 10 high boiling point solvent] and insoluble organic liquid is 0.0. It is desirable that the range is from / to 100.

As the magnetic particles of the capsule toner of the present invention, known magnetic particles (magnetized particulate matter) for magnetic toners can be used. Examples of such magnetic particles include magnetic particles made of elemental metals, alloys, or metal compounds such as cobalt, iron, or nickel.

The content of magnetic particles is 1 O-JO weight% based on the total weight, and is 3! -60 weight ratio is especially preferable.

The resin forming the outer shell of the capsule toner of the present invention may be a polyurethane resin and/or a polyurea resin, and among these, polyurea is particularly preferred.

In the present invention, 5i is added to the outer shell surface of the capsule toner.
Metal fine particles such as 02, T i 02, and Al2O3 may be attached or contained.

The surfaces of these metal fine particles may be treated with a silane coupling agent or a titanium coupling agent.

There is no particular limit to the content of the metal oxide, but it is 0.0 based on the weight of the capsule toner to which no metal fine particles are attached or contained! It is preferable that it is attached or contained within the range of ~10% by weight, and o, i~! It is particularly preferable that it be attached or contained within the weight range.

Next, a capsule toner having an outer shell of a polyurethane resin and/or a d5 urea resin according to the present invention will be described below.

A method for producing microcapsules by forming an outer shell made of polyurethane resin and/or polyurea resin around a core substance containing magnetic particles and a binder dispersed in the form of oil droplets in an aqueous liquid is already known. sb, these known methods can also be used to produce the capsule toner of the present invention.

For example, an interfacial polymerization method can be mentioned as a method for manufacturing microcapsules using a polymerization reaction that can be used for manufacturing a capsule toner. Also,
Other examples of methods for producing microcapsules using polymerization reactions that can be used in the present invention include internal polymerization methods and external polymerization methods.

The outer shell made of polyurethane resin and/or polyurea resin is made of polyisocyanate such as diincyanate, triisocyanate, tetrainocyanate, polyincanate prepolymer, and polyamine such as diamine, triamine, tetraamine, or two amine groups. It is known that the shells of microcapsules can be easily formed by reacting prepolymers containing the above, piperazine and its derivatives, polyols, etc. by interfacial polymerization in an aqueous solvent.

Shells consisting of a composite wall of polyurethane resin and polyurea resin are particularly suitable for forming capsule toners containing magnetic particles within the core material.

After preparing the υ microcapsules by forming an outer shell around the core material, the microcapsules are separated from the liquid phase, washed with water, and then dried.

This separation and drying operation is usually carried out by heating and drying a slurry containing microcapsules.

Note that the separated and dried microcapsules can be further subjected to heat treatment. This heat treatment particularly improves the powder properties of the capsule toner. Heat treatment! Q～JOO
Preferably it is carried out at a temperature in the range 0C, and furthermore? O~
Particular preference is given to heating at a temperature in the range of izo 0C. The heating time can be determined as appropriate depending on the heating temperature, the type of core material used, etc., but it is usually heated for 70 minutes, preferably 2 to 3 hours.

There are no particular limitations on the equipment and equipment used for the heat treatment, and examples of the equipment include an electric furnace, a matzuru furnace, a hot plate, an electric dryer, a fluidized bed dryer, an infrared dryer, and the like.

A predetermined amount of metal oxide fine particles are mixed into the capsule toner thus prepared. There are no particular restrictions on the mixing method, and commonly used mixers, V-type mixers, etc. can be used.

The obtained capsule toner exhibits excellent powder properties, especially its fluidity.

Next, examples of the present invention will be shown. In addition, in the examples, "chi"
means "weight class" unless otherwise specified.

[Example 1] Polyisobutyl methacrylate (trade name Niacrybase, manufactured by MM-COOZ-Koni Fujikura Kasei) was mixed with /-isopropyl-7enyl-2-phenylethane and 5opar-H (aliphatic saturated Aqueous dispersion (magnetic ink) was prepared by cross-dispersing liquid Hiroshi Og, which is a hydrocarbon mixture (manufactured by Ekun Kagaku ■) mixed in an amount ratio of T and J, and magnetite magnetic particles Hiroshi Og in an automatic mortar. Prepared.

Separately, a solution was prepared by dissolving 9.9 g of an addition compound of 1 mole of xylylene diisocyanate 37-trimethylolpropane (trade name: Takenate D-110H, manufactured by Takeda Pharmaceutical Company Ltd.) in ethyl acetate λOg. An oily phase was prepared by mixing with the above dispersion (magnetic ink). However, the preparation of this oily phase mixed liquid (mixture of core material and outer shell forming material) was carried out while controlling the liquid temperature to 250C or less.

Methyl cellulose (methoxy group 111 conversion degree: /,?
, an aqueous medium was prepared by adding 0.2 g of diethylenetriamine to 200 g of a Hiroki water bath solution with an average molecular weight of /yo000, and the temperature of the aqueous medium was /! Cooled to 0C.

The above oily phase mixed liquid was emulsified and dispersed in this aqueous medium to obtain an oil-in-water emulsion in which the average size of oil droplets in the emulsion was about 1/2 μm.

Approximately 70 minutes after preparing the emulsion, 2.3 g of diethylenetriamine in a polyhydric bath solution was gradually added dropwise, and ≦O
The mixture was stirred for 3 hours in a QC constant temperature bath to complete encapsulation.

The resulting microcapsule dispersion was allowed to stand to allow the microcapsules to settle, the upper aqueous layer was discarded, and washing water was added to the dispersion, stirred, and allowed to stand.

This washing operation was repeated 20 times to remove methylcellulose and the like adhering to the surface of the microcapsules. The washed microcapsule slurry was dried in an oven set at 100C to obtain a capsule toner. Hydrophobic silica (product name: Aerosil R-
Def4I (manufactured by Nippon Aerosil ■) was added in an amount of 1 weight per weight of the capsule toner and mixed.

This capsule toner had each capsule particle existing independently and exhibited very smooth fluidity.

The pressure fixing characteristics of the capsule toner obtained above were evaluated by the following method.

A magnetic latent image formed by a conventional magnetic recording method was developed with the above capsule toner to form a toner image, and then the toner image was transferred to transfer paper to obtain a visible image. When this visible image was pressure-fixed using a pressure fixing roller at a pressure of rOKq/cm2, a copy image with good fixability was obtained. Even when the copy image fixed under pressure on the copy paper was rubbed with a finger, the toner did not peel off and the copy image was not affected.

Image Area [Comparative Example 1] A toner consisting of 700 parts by weight of styrene-butyl methacrylate copolymer, 60 parts by weight of magnetite, and 3 parts by weight of nigrosine was prepared according to a conventional method. A copy image was obtained using this toner in the same manner as in Example 1. In this case, the fixing pressure J! It was established in OK4/rrL2.

When the image area was rubbed with a finger, the image area peeled off and stained the white background.

In addition, the image area and white background area were also glossy.

Claims (1)

[Claims] 1. Contains a polymer, a solvent with a boiling point of 150°C or higher that can dissolve or swell the polymer, and an organic liquid with a boiling point of 100 to 250°C that does not substantially dissolve or swell the polymer. A magnetography capsule comprising a core material containing a mixture and magnetic particles, and an outer shell formed around the core material, and containing the magnetic particles in an amount of 10 to 60% by weight of the total weight. toner. 2. The polymer is a homopolymer or copolymer of acrylic acid ester, a homopolymer or copolymer of methacrylic acid ester, or styrene/butadiene/
Claim 1 characterized in that it is a copolymer.
Capsule toner for magnetography as described in . 3. The solvent with a boiling point of 150°C or higher is a phthalate ester,
2. The capsule toner for magnetography according to claim 1, wherein the toner is a phosphoric acid ester, an alkylnaphthalene, or a diaryl alkane. 4. Claim 1, characterized in that the organic liquid having a boiling point of 100 to 250°C is an aliphatic saturated hydrocarbon or an organic liquid mixture containing an aliphatic saturated hydrocarbon as a main component. Capsule toner for magnetography. 5. The capsule toner for magnetography according to claim 1, wherein the outer shell is made of a polyurea resin and/or a polyurethane resin and a wall. 6. The capsule toner for magnetography according to claim 1, wherein the magnetic particles are a single metal, an alloy, or a metal compound such as cobalt, iron, or nickel.