JPH05204238A - Developing method - Google Patents

Abstract

PURPOSE:To stably form a high-density image without dust and staining and with high resolution by constituting a part where a regulating member abuts on a developer carrier of a conductive fiber member connected to a power source. CONSTITUTION:In a one-component developing method in which a latent image on an electrostatic latent image forming body is developed by using thermal dissociation type capsule toner, at least the developer carrier 1 carrying developer and a regulating plate 3 which regulates the thickness of the thin layer of the developer formed on the carrier 1 and applies charge to the developer are provided. The part where the regulating plate 3 abuts on the developer carrier 1 is constituted of the conductive fiber member and voltage is impressed on the developer carrier 1 and the conductive fiber member, respectively. Therefore, the layer thickness of the developer layer on the carrier 1 is regulated and the charge is fully applied to the thermal dissociation type capsule toner, so that the electrostatic charging of the developer which is stable and the electrostatic charged amount is adjusted is performed and the high-density image is stably formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing method used in plain paper copying machines, laser printers, plain paper facsimiles and the like. More specifically, it relates to a one-component developing method for developing a latent image on an electrostatic latent image forming body using a heat dissociative capsule toner.

[0002]

2. Description of the Related Art In electrophotography, an electrostatic latent image formed by optical means is first developed in a developing process and then transferred to a recording medium such as recording paper in a transferring process. The image is formed by being transferred and further fixed by a fixing roller system having high heat and high pressure in a fixing step. In such a conventional image forming method, the temperature of the heating element of the fixing device is very high and a large pressure is required during the process from the formation of the electrostatic latent image to the fixing to the recording medium. It is the current situation.

On the other hand, since the photoconductor and the developing device need to be kept at room temperature, it is necessary to keep a considerable distance between the fixing section and the photoconductor and the developing device. It is necessary to remove the heat generated from the outside of the system. Noise and heat generated by the forced heat dissipation device are also a cause of environmental damage in offices and the like. The fixing step exists independently, usually at a high temperature of around 200 ° C. and at 2 Kg /
Since fixing is performed with a fixing device having a linear pressure of cm or more, expensive heat-resistant resin and heat-resistant rubber are required around the fixing device. Also, when fixing at such a high temperature, the paper curls,
It has been pointed out that troubles such as jamming are likely to occur, and the paper absorbs heat depending on the thickness of the paper, resulting in defective fixing.

Further, if the fixing temperature is high, it takes time to reach the set temperature, and quick printing cannot be performed. Therefore, it is not suitable for a device such as a facsimile machine which requires quick printing. On the other hand, with conventional toners, which try to fix at a fixing temperature of about 100 ° C. or less, it is not possible to expect the resin in the toner to soften due to heat. A linear pressure is required, and in that case, not only a large-scale fixing device is used, but also the fixing strength is inferior to that of heat fixing, and problems such as paper wrinkling occur.

From these viewpoints as well, development of a new system and a toner adapted thereto is expected. As a toner that meets such expectations, the effectiveness of using a thermal dissociation type capsule toner is being evaluated. However, since the thermal dissociative capsule toner has properties different from those of the conventional toner, development of a developing method suitable for using the thermal dissociative capsule toner is required.

The developing system is an important part of the electrophotographic process, and various types of systems and materials have been reported in the past. Among them, the two systems consisting of toner and carrier are systematically included. There are two types, one is a toner type and the other is a one-component type using only toner. The magnetic brush type is mainly used in both types.

The basis of the two-component system using a developer and a replenishment toner composed of a toner containing a magnetic carrier and a colorant was devised in 1952 (USP26).
18551), and the invention of the magnetic brush developing method in 1953 (USP27886439) contributes greatly to faithful image reproducibility and downsizing of the developing device. However, the drawbacks of the two-component developing system are that the image quality is poorly maintained, the developer is deteriorated, the concentration of the developer needs to be adjusted, it is not suitable for further size reduction, and toner scattering easily occurs. Various problems have been pointed out.

On the other hand, since the one-component developing method is carrierless, the developing device is more compact than the two-component developing method because the device for keeping the toner concentration constant and the stirring device for the developer are not required. Can be designed to However, in the one-component developing method, there is no charging partner like the carrier,
It is said that obtaining stable charging is a major issue. The following three types of methods are known as methods for obtaining such charging. That is, (1) a method of simultaneously charging during development using a latent image electric field (USP41219)
31, JP-A-53-31136, JP-A-50-9.
No. 2137 and Japanese Patent Laid-Open No. 54-134640), and (2) a method of transferring and receiving charges inside the developing (Japanese Patent Laid-Open No. 53-47936, Japanese Patent Laid-Open No. 59-33908).
JP-A-53-4549) and (3) a method of thinning a toner layer on a sleeve and charging it (JP-A-50-45639).

A developing method using a magnetic toner is known as a one-component developing method, and a method using a conductive magnetic toner (10 ⁸ Ω · cm or less) was previously devised (USP 3909258). , It is difficult to corona transfer with this low resistance toner, and the magnetic toner is currently 10
High resistance toner of ¹⁴ Ω · cm or more is used. But,
Since magnetic toner uses magnetic powder, it has a high specific gravity, and since it uses a magnet roll as in the two-component system,
There is a drawback that the developing tank becomes heavy. In addition, since magnetic toner is inferior in fluidity, triboelectrification property is not sufficient and therefore uniform development is difficult to be performed. Therefore, unless fine adjustment or device improvement is made, background stains and toner scattering There was a problem that the inside of the aircraft was contaminated due to. Also, 30-70%
The disadvantages of using magnetic powders are that images are deteriorated due to a decrease in charge amount under high humidity and that a transparent vivid color toner cannot be obtained because the magnetic powders are black or brown.

On the other hand, non-magnetic 1 which is a developing system that does not contain such magnetic powder and does not use a carrier.
A component development system has been proposed. For example, JP-A-59-
228721, JP-A-60-45270,
JP-A-62-19884, JP-A-62-8997
No. 5 publication and the journal of the Electrophotographic Society, Vol. 26, No. 2, 107 to 1.
On page 14, a non-magnetic one-component developing system is reported. According to these methods, since the toner does not contain a magnetic material, there is no image deterioration due to a decrease in the charge amount under high humidity,
A clear vivid color toner can be obtained, and since the magnet roll is not used, the developing device is small and lightweight. However, during printing, triboelectrification becomes unstable due to the contamination of the developer carrier and the toner thinning member with the toner, and this tendency becomes remarkable when the temperature and humidity are high, resulting in image deterioration. Points are pointed out.

That is, in the developing device used in the conventional non-magnetic one-component developing system, since the one-component developer is used, the developer is supplied onto the developer carrying member and the developer conveyed to the developing area. Charging, further, removal of the developer remaining on the developer carrier after development from the developer carrier, stirring of the developer,
If the circulation is not stable, there is a problem that image deterioration such as image blurring and background stain occurs. For example, in a conventional developing device that simultaneously charges the developer T and forms a thin layer by the pressure contact blade 43 as shown in FIG. 4, the charge amount of the developer T is not stable because of frictional charging, and the pressure contact blade 43 is not supported. However, there is a problem in that reliability is poor due to a large influence of changes in the material and surface condition of the product, and changes in the surrounding environment. Further, the developer T not used for developing the electrostatic latent image on the electrostatic latent image forming body 42 but remaining on the developer carrying body 41 remained without being removed from the developer carrying body 41. Since the developer T is used for the next development together with the rotation of the developer carrier 41, there are problems in the stability of the charge amount of the developer T and the stirring property of the developer T. Furthermore, since the contact surface of the pressure contact blade, which is the regulating member, with the developer is substantially flat, when passing through the blade,
There is also a problem that the triboelectric charge is not sufficient with respect to the developer layer and the charge becomes uneven.

In order to improve these problems, a method of increasing frictional resistance to improve triboelectrification can be considered.
When the toner is a thermal dissociative capsule toner as used in the present invention, if a large frictional force or pressure is applied to the toner, there is a risk of damage to the outer shell of the thermal dissociative capsule toner and the life of the toner is shortened. The problem arises.

Therefore, in view of the above points, the object of the present invention is to
In a one-component developing method for developing a latent image on an electrostatic latent image forming body using a heat dissociative capsule toner, supply of a developer,
Charging, thin layer formation, supply and transport of developer to the developing area, transfer of developer to electrostatic latent image, removal of developer from developer carrier,
An object of the present invention is to provide a developing method capable of forming a high quality image by stably stirring and circulating.

[0014]

The gist of the present invention is (1)
In a one-component developing method for developing a latent image on an electrostatic latent image forming body using a heat dissociative capsule toner, a developer carrying body carrying at least a developer, and a development formed on the developer carrying body. A developing device having a regulating member for regulating the layer thickness of a thin layer of the developer and for imparting an electric charge to the developer, wherein a portion of the regulating member that is in contact with the developer carrier is a conductive fibrous material. A developing method characterized in that a voltage is applied to the developer carrying member and the conductive fibrous member, respectively, using a device comprising members, (2) The main component of the shell material of the heat dissociation type capsule toner is The developing method according to (1) above, which comprises a resin having at least one bond of a heat dissociable urethane bond, a thiol urethane bond, or an s-thiourethane bond, and (3) above. Thermal dissociation, which is the main component of shell materials The above (2), wherein the retan resin has 30% or more of the bonds resulting from the reaction with the phenolic hydroxyl group and / or the thiol group among the bonds involving all the isocyanate groups and / or isothiocyanate groups. Developing method of (1) above, wherein the softening point of the heat dissociative capsule toner is 80 ° C. to 150 ° C.
To (3), the developing method according to (5), wherein the conductive fibrous member is a conductive fibrous substance formed in a brush shape, and the developing method according to (1) to (4). The developing method according to the above (1) to (4), wherein the fibrous member is a conductive non-woven fabric, a regular woven cloth or electric flock, and (7) a developer carrier and conductivity. The developing method according to any one of (1) to (4) above, which uses an apparatus equipped with a control unit for controlling each voltage applied to the fibrous member.

The toner used in the present invention is a thermal dissociation type capsule toner. The thermal dissociation type capsule toner is a toner having a shell having a property that the shell structure is weakened by heat and containing a core material that can be fixed by pressure at low temperature.
That is, the structure of the shell changes due to heat, and the core material is released and fixed when pressure is applied.

Such a heat dissociative capsule toner can usually be easily obtained by the following manufacturing method. (1) A spray drying method (spray drying method) in which the core substance is dispersed in a non-polymer aqueous solution or a polymer emulsion and then the dispersion is spray-dried, and (2) around the core substance from a mixed aqueous solution of an ionic polymer colloid. Phase separation method (coacervation method) in which microcapsules are formed from a simple emulsion through a complex emulsion by (3) a core substance solution or dispersion is W / O or O
/ W type emulsion system, at the same time collecting the shell material monomer (A) at the interface, in the next step the interfacial polymerization method in which the monomer (B) and the monomer (A) react, in addition to in situ
The u polymerization method, the liquid hardening coating method, the air suspension coating method, the electrostatic coalescence method, the vacuum vapor deposition coating method and the like can be mentioned. In the present invention, the thermal dissociation type capsule toner produced by the interfacial polymerization method or the spray drying method is preferably used.
In the interfacial polymerization method, not only the functional separation of the core material and the shell material is easy, but also a uniform toner can be produced in an aqueous system, and a substance having a low softening point can be used for the core material. A toner having desirable properties can be obtained.

As the shell material, a styrene resin (JP-A-48)
-80407), a polyamide resin (JP-A-58)
-66948), an epoxy resin (JP-A-59-59).
No. 148066), a polyurethane resin (Japanese Patent Laid-Open No. Sho 5)
No. 7-179860), polyurea-based resins (JP-A No. 62-150262), and many others have been devised. Examples of the heat-pressure fixing substance contained in the core material include thermoplastic resins having a glass transition point (Tg) of 10 ° C. or higher and 50 ° C. or lower, such as polyester resin, polyamide resin, polyester polyamide resin, and vinyl resin. ..

With respect to the thermal characteristics of the core material, the structure and thermal characteristics of the shell material are significantly involved in the fixability of the toner as a whole. Since it has both storage stability and low-temperature fixability, it is a very preferable material in the image forming method of the present invention. The main component of such a shell material is a resin having at least one bond of thermal dissociative urethane bond, thiol urethane bond, or s-thiourethane bond. Furthermore, in the heat dissociable urethane resin, which is the main component of this shell material, among the bonds involving all the isocyanate groups and / or isothiocyanate groups, the number of the bonds due to the reaction with the phenolic hydroxyl group and / or the thiol group is the number. Is 30% or more. For example, an isocyanate compound and / or an isothiocyanate compound and a phenolic hydroxyl group and / or
Alternatively, a resin obtained by a reaction with a compound having a thiol group or the like is preferably used (Japanese Patent Application No. 14231/1991).
issue).

More specifically, for example, a heat dissociable capsule toner is a heat-meltable core material containing at least a colorant,
An encapsulated toner composed of an outer shell provided so as to cover the surface of the core material, wherein the main component of the outer shell is
(1) 0 to 30 mol% of a monovalent isocyanate compound and / or isothiocyanate compound based on the whole isocyanate compound and / or isothiocyanate compound, (2) a divalent or higher valent isocyanate compound and / or an isothiocyanate compound And / or 100 to 70 mol% of the total isothiocyanate compound, and (3) a compound having one active hydrogen that reacts with an isocyanate group and / or an isothiocyanate group with respect to the entire compound that reacts with an isocyanate group and / or an isothiocyanate group. 0-30
Mol%, (4) out of 100 to 70 mol% of all compounds that react with an isocyanate group and / or an isothiocyanate group containing a compound having two or more active hydrogens that react with an isocyanate group and / or an isothiocyanate group, ) + (2)
The ratio of the number of moles of (3) + (4) to 1: 1 to 1:20
Of the resin obtained by reacting within the range of, and at least 30% or more of the bonds involving all isocyanate groups and / or isothiocyanate groups in the resin are bonds showing thermal dissociation. Is mentioned.

The bond exhibiting thermal dissociation is preferably a bond derived from the reaction of a phenolic hydroxyl group and / or a thiol group with an isocyanate group and / or an isothiocyanate group. Specifically, the monovalent isocyanate compound of (1) above includes ethyl isocyanate, octyl isocyanate, 2-chloroethyl isocyanate, chlorosulfonyl isocyanate, cyclohexyl isocyanate, n-dodecyl isocyanate, and butyl isocyanate. , N-hexyl isocyanate, lauryl isocyanate, phenyl isocyanate, m-chlorophenyl isocyanate, 4-chlorophenyl isocyanate, p-cyanophenyl isocyanate, 3,4-dichlorophenyl isocyanate, o-tolyl isocyanate, isocyanic acid m-tolyl, p-tolyl isocyanate, p-isocyanate
-Toluenesulfonyl, 1-naphthyl isocyanate, o-nitrophenyl isocyanate, m-nitrophenyl isocyanate, p-nitrophenyl isocyanate, phenyl isocyanate, p-bromophenyl isocyanate, o-methoxyphenyl isocyanate, isocyanate Acid m-methoxyphenyl, p-methoxyphenyl isocyanate,
Examples thereof include monovalent isocyanate compounds such as ethyl isocyanato acetate, butyl isocyanato acetate, and trichloroacetyl isocyanate.

Examples of the divalent or higher-valent isocyanate compound (2) include, for example, 2,4-tolylene diisocyanate, a dimer of 2,4-tolylene diisocyanate, and 2,6-
Tolylene diisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, 3,3'-dimethyl-diphenyl-4,4'-diisocyanate, 3, 3'-Dimethyl-diphenylmethane-
Aromatic isocyanate compounds such as 4,4'-diisocyanate, metaphenylene diisocyanate, triphenylmethane-triisocyanate, polymethylenephenyl isocyanate, etc., Aliphatic compounds such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, dimer acid diisocyanate, etc. Alicyclic isocyanate compounds such as isocyanate compounds, isophorone diisocyanate, 4,4'-methylenebis (cyclohexyl isocyanate), methylcyclohexane-2,4 (or 2,6) diisocyanate, 1,3- (isocyanatomethyl) cyclohexane Examples thereof include isocyanate compounds such as an adduct of 3 mol of diisocyanate and 1 mol of trimethylolpropane. Examples of the compound having an isothiocyanate group include compounds such as phenyl isothiocyanate, xylylene-1,4-diisothiocyanate, and ethylidyne diisothiocyanate. Among them, a compound in which an isocyanate group is directly bonded to an aromatic ring is preferably used because it has an effect of lowering the thermal dissociation temperature after the urethane bond is formed.

The monovalent isocyanate compound and / or isothiocyanate compound (1) can be used up to 30 mol% of the whole isocyanate compound and / or isothiocyanate compound for the purpose of adjusting the molecular weight of the outer shell resin. If it exceeds mol%, the storage stability of the heat dissociative capsule toner deteriorates, which is not preferable.

As the compound having one active hydrogen which reacts with the isocyanate group and / or the isothiocyanate group in the above (3), methyl alcohol, ethyl alcohol,
Aliphatic alcohols such as propyl alcohol, isopropyl alcohol, butyl alcohol, isobutyl alcohol, t-butyl alcohol, pentyl alcohol, hexyl alcohol, cyclohexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, lauryl alcohol, stearyl alcohol, phenol , O-cresol, m-cresol, p-cresol, 4-butylphenol, 2-sec
-Butylphenol, 2-tert-butylphenol, 3
-Tert-butylphenol, 4-tert-butylphenol, nonylphenol, isononylphenol, 2-propenylphenol, 3-propenylphenol, 4-
Propenylphenol, 2-methoxyphenol, 3-
Methoxyphenol, 4-methoxyphenol, 3-acetylphenol, 3-carbomethoxyphenol, 2
-Chlorophenol, 3-chlorophenol, 4-chlorophenol, 2-bromophenol, 3-bromophenol, 4-bromophenol, benzyl alcohol,
1-naphthol, 2-naphthol, 2-acetyl-1-
Examples thereof include compounds such as aromatic alcohols such as naphthol and amides such as ε-caprolactam.

Among them, the phenol derivative represented by the following formula (I) is preferably used.

[Chemical 1] (In the formula, R ₁ , R ₂ , R ₃ , R ₄ , and R ₅ are independently H, or an alkyl group having 1 to 9 carbon atoms, an alkenyl group, an alkoxy group, an alkanoyl group, a carboalkoxy group, or an aryl group. Or halogen.)

Among the compounds having two or more active hydrogens which react with the isocyanate group and / or the isothiocyanate group of the above (4), the divalent or higher valent alcohol compound is
For example, catechol, resorcin, hydroquinone, 4-
Methylcatechol, 4-t-butylcatechol, 4-acetylcatechol, 3-methoxycatechol, 4-phenylcatechol, 4-methylresorcin, 4-ethylresorcin, 4-t-butylresorcin, 4-hexylresorcin, 4-chloro Resorcin, 4-benzylresorcin, 4-acetylresorcin, 4-carbomethoxyresorcin, 2-methylresorcin, 5-methylresorcin, t-butylhydroquinone, 2,5-di-t-butylhydroquinone, 2,5-di- t-amylhydroquinone, tetramethylhydroquinone, tetrachlorohydroquinone, methylcarboaminohydroquinone, methylureidohydroquinone, benzonorbornene-3,6-
Diol, bisphenol A, bisphenol S, 3,3 '
-Dichlorobisphenol S, 2,2'-dihydroxybenzophenone, 2,4-dihydroxybenzophenone, 4,4 '
-Dihydroxybenzophenone, 2,2'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl, 2,2'-dihydroxydiphenylmethane, 3,4-bis (p-hydroxyphenyl) hexane, 1,4-bis (2- ( p-hydroxyphenyl) propyl) benzene, bis (4-hydroxyphenyl) methylamine, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,
5-dihydroxyanthraquinone, 2-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol,
2-hydroxy-3,5-di-t-butylbenzyl alcohol, 4-hydroxy-3,5-di-t-butylbenzyl alcohol, 4-hydroxyphenethyl alcohol, 2
-Hydroxyethyl-4-hydroxybenzoate, 2
-Hydroxyethyl-4-hydroxyphenyl acetate, resorcin mono-2-hydroxyethyl ether,
Hydroxyhydroquinone, gallic acid, ethyl 3,4,5-trihydroxybenzoate and the like can be mentioned. Among them, a catechol derivative represented by the following formula (II) or a resorcin derivative represented by the following formula (III) is preferably used.

[0026]

[Chemical 2] (In the formula, R ₆ , R ₇ , R ₈ , and R ₉ independently represent H, or an alkyl group having 1 to 6 carbon atoms, an alkenyl group, an alkoxy group, an alkanoyl group, a carboalkoxy group, an aryl group, or halogen. Show.)

[Chemical 3] (In the formula, R ₁₀ , R ₁₁ , R ₁₂ , and R ₁₃ independently represent H, or an alkyl group having 1 to 6 carbon atoms, an alkenyl group, an alkoxy group, an alkanoyl group, a carboalkoxy group, an aryl group, or halogen. Show.)

Other compounds having at least one functional group other than a hydroxyl group which reacts with an isocyanate group and / or an isothiocyanate group and having at least one phenolic hydroxyl group include, for example,
o-hydroxybenzoic acid, m-hydroxybenzoic acid, p
-Hydroxybenzoic acid, 5-bromo-2-hydroxybenzoic acid, 3-chloro-4-hydroxybenzoic acid, 4-chloro-2-hydroxybenzoic acid, 5-chloro-2-hydroxybenzoic acid, 3,5-dichloro -4-Hydroxybenzoic acid, 3-methyl-2-hydroxybenzoic acid, 5-methoxy-2-hydroxybenzoic acid, 3,5-di-t-butyl-4-hydroxybenzoic acid, 4-amino-2-hydroxy Benzoic acid, 5-amino-2-hydroxybenzoic acid, 2,
5-dinitrosalicylic acid, sulfosalicylic acid, 4-hydroxy-3-methoxyphenylacetic acid, catechol-4-
Carboxylic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 3,4
-Dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 3,4-dihydroxyphenylacetic acid, m-hydroxycinnamic acid, p-hydroxycinnamic acid, 2-amino-4-methylphenol, 2-amino-5-methylphenol 5,
-Amino-2-methylphenol, 3-amino-2-naphthol, 8-amino-2-naphthol, 1-amino-
2-naphthol-4-sulfonic acid, 2-amino-5-naphthol-4-sulfonic acid, 2-amino-4-nitrophenol, 4-amino-2-nitrophenol, 4-amino-2,6-dichlorophenol , O-aminophenol, m-aminophenol, p-aminophenol, 4
-Chloro-2-aminophenol, 1-amino-4-hydroxyanthraquinone, 5-chloro-2-hydroxyaniline, α-cyano-3-hydroxycinnamic acid, α-cyano-4-hydroxycinnamic acid, 1-hydroxynaphthoene Acid, 2-hydroxynaphthoic acid, 3-hydroxynaphthoic acid, 4-hydroxyphthalic acid and the like can be mentioned.

Further, polythiol compounds having one or more thiol groups in one molecule include ethanethiol, 1
-Propanethiol, 2-propanethiol, thiophenol, bis (2-mercaptoethyl) ether, 1,2
-Ethanedithiol, 1,4-butanedithiol, bis (2-mercaptoethyl) sulfide, ethylene glycol bis (2-mercaptoacetate), ethylene glycol bis (3-mercaptopropionate), 2,2-
Dimethylpropanediol bis (2-mercaptoacetate), 2,2-dimethylpropanediol bis (3-mercaptopropionate), trimethylolpropane tris (2-mercaptoacetate), trimethylolpropane tris (3-mercaptopropionate) ), Trimethylolethanetris (2-mercaptoacetate), trimethylolethanetris (3-mercaptopropionate), pentaerythritol tetrakis (2
-Mercaptoacetate), pentaerythritol tetrakis (3-mercaptopropionate), dipentaerythritol hexakis (2-mercaptoacetate), dipentaerythritol hexakis (3-mercaptopropionate), 1,2-dimercaptobenzene ,
4-methyl-1,2-dimercaptobenzene, 3,6-dichloro-1,2-dimercaptobenzene, 3,4,5,6-tetrachloro-1,2-dimercaptobenzene, xylylenedithiol, 1 Examples include 3,3,5-tris (3-mercaptopropyl) isocyanurate.

In the resin for heat dissociable shells used in the present invention, the bonds that dissociate thermally are all isocyanate groups and / or
Alternatively, among the bonds involving isothiocyanate groups, the number is at least 30% or more, preferably 50%. If the number of the bonds that undergo thermal dissociation is less than 30% of the number of bonds involving all isocyanate groups and / or isothiocyanate groups, the capsule shell strength will not be sufficiently reduced during heat and pressure fixing, leading to excellent fixing performance of the core material. I can't.

In the heat dissociative capsule toner of the present invention, of the bonds involving all the isocyanate groups and / or isothiocyanate groups, the number of bonds due to the reaction with the phenolic hydroxyl group and / or the thiol group is 30%. A compound having a functional group which reacts with an isocyanate group other than a phenolic hydroxyl group and / or a thiol group in a range not exceeding less than, for example, malonic acid esters,
Active methylene group-containing compounds such as acetoacetic acid esters, oximes such as methyl ethyl ketone oxime,
Carboxylic acid, polyol, polyamine, aminocarboxylic acid, aminoalcohol and the like can be used as the shell forming substance.

In the present invention, the compound (3) having one active hydrogen that reacts with the isocyanate group and / or isothiocyanate group is 30 mol% of the whole compound that reacts with the isocyanate group and / or isothiocyanate group.
However, if it exceeds 30 mol%, the storage stability of the heat dissociative capsule toner is deteriorated, which is not preferable. In addition, the number of moles of the isocyanate compound and / or isothiocyanate compound [(1) + (2)] constituting the outer shell and the compound [(3) + (4)] which reacts with the isocyanate group and / or isothiocyanate group The ratio is preferably 1: 1 to 1:20 to prevent unreacted isocyanate groups from remaining.

In the production of the thermal dissociation type capsule toner,
The outer shell is preferably formed by interfacial polymerization or in-situ polymerization.For example, an outer shell forming material having a core particle as a core substance and a number average particle diameter of 1/8 or less of the number average particle diameter of the mother particles is used. It may be carried out by a dry method in which the shell particles are rapidly stirred in an air stream to form an outer shell.

The outer shell resin can be produced without a catalyst, but when a catalyst is used, a tin-based catalyst such as dibutyltin dilaurate, 1,4-diazabicyclo [2.2.2] octane, N, N,
Known urethane catalysts such as amine-based catalysts such as N-tris (dimethylaminopropyl) -hexahydro-S-triazine can be used.

The resin used for the core material of the thermal dissociation type capsule toner in the present invention has a glass transition point (Tg) of 10 or less.
Thermoplastic resins such as polyester resins, polyester / polyamide resins, polyamide resins, and vinyl resins having a temperature of not lower than 50 ° C. and not higher than 50 ° C. are mentioned, and vinyl resins are particularly preferable. If the glass transition point is lower than 10 ° C, the storage stability of the heat dissociative capsule toner is deteriorated, and if it exceeds 50 ° C, the fixing strength of the heat dissociative capsule toner is deteriorated, which is not preferable.

Examples of the monomer constituting the vinyl resin include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-
Styrene or styrene derivatives such as ethylstyrene, 2,4-dimethylstyrene, p-chlorostyrene, vinylnaphthalene, etc., such as ethylene, propylene, butylene,
Ethylenically unsaturated monoolefins such as isobutylene and the like, vinyl esters such as vinyl chloride, vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propionate, vinyl formate and vinyl caproate, for example acrylic acid,
Methyl acrylate, ethyl acrylate, acrylic acid n-
Propyl, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate,
Amyl acrylate, cyclohexyl acrylate, n-octyl acrylate, isooctyl acrylate, decyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, methoxyethyl acrylate, 2-hydroxyethyl acrylate, acrylic acid Glycidyl, 2-chloroethyl acrylate, phenyl acrylate, α-chloromethyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, T-Butyl methacrylate, amyl methacrylate, cyclohexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate, decyl methacrylate, lauryl methacrylate, methacrylic acid Ethylenic monocarboxylic acids and their esters such as 2-ethylhexyl acid salt, stearyl methacrylate, methoxyethyl methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and the like. , An ethylenic monocarboxylic acid substitution product such as acrylonitrile, methacrylonitrile, acrylamide, etc., an ethylenic dicarboxylic acid such as dimethyl maleate and the substitution product thereof, vinyl ketones such as vinyl methyl ketone, for example vinyl methyl ether Vinylidene halides such as vinylidene chloride and N-vinyl compounds such as N-vinylpyrrole and N-vinylpyrrolidone. is there. Preferably, of the components constituting the resin for the core material according to the present invention, styrene or a styrene derivative is preferably 50 to 90 parts by weight for forming the main skeleton of the resin, and ethylene is used for adjusting the thermal characteristics such as the softening temperature of the resin. The monocarboxylic acid and its ester are preferably used in an amount of 10 to 50 parts by weight.

When a cross-linking agent is added to the monomer composition constituting the resin for the core material according to the present invention, known cross-linking agents can be appropriately used (combined with two or more if necessary). .. When the amount of these cross-linking agents used is large, the toner is less likely to be melted by heat, resulting in poor heat fixing property or heat pressure fixing property. Further, when the amount used is small, it is difficult to prevent the offset phenomenon in which a part of the toner adheres to the roller surface without being completely fixed to the paper and is transferred to the next paper in the thermal pressure fixing. Further, the amount of these crosslinking agents used is preferably 0.001 to 15% by weight (more preferably 0.1 to 10% by weight) based on the polymerizable monomer. If necessary, the core material may contain one or more known anti-offset agents for the purpose of improving offset resistance in heat and pressure fixing. The ratio of these offset preventing agents to the resin in the core material is preferably 1 to 20% by weight.

Although the colorant is contained in the core material of the heat dissociative capsule toner of the present invention, all the dyes, organic or inorganic pigments used in the conventional colorants for toner can be used. Usually 1 for 100 parts by weight of resin in the core material
About 15 parts by weight is used.

In the outer shell material of the heat dissociative capsule toner of the present invention, as a charge control agent, a metal-containing dye such as a metal complex of an organic compound having a carboxyl group or a nitrogen group conventionally used in toners. , Nigrosine and the like may be added in appropriate amounts. Further, this charge control agent may be mixed with a toner and used.

In the heat dissociative capsule toner of the present invention, a fluidity improver, a cleaning property improver and the like can be used if necessary. Further, an additive for adjusting the developability, for example, fine particle powder of a polymer of methacrylic acid methyl ester may be used. Further, a small amount of carbon black may be used for toning and resistance adjustment. The softening point of the heat dissociative capsule toner of the present invention is preferably 80 ° C. or higher and 150 ° C. or lower, but if it is lower than 80 ° C., the offset resistance deteriorates, and if it exceeds 150 ° C., the fixing strength deteriorates, which is not preferable. The particle size of the heat dissociative capsule toner according to the present invention is not particularly limited,
The average particle size is usually 3 to 30 μm. The thickness of the outer shell of the heat dissociative capsule toner is preferably 0.01 to 1 μm, and 0.01 μm
If it is less than m 3, blocking resistance is deteriorated, and if it exceeds 1 μm, heat melting property is deteriorated, which is not preferable.

Next, the developing device used in the developing method of the present invention using the heat dissociative capsule toner as a developer will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an example of an image recording apparatus provided with a developing device used in the present invention. This developing device (hereinafter abbreviated as a first developing device) is a metal roller rotatably supported so as to face a photoconductor (electrostatic latent image forming body) 4 on which an electrostatic latent image is formed with a gap g. And a roller-shaped porous conductive elastic member 2 which is a conductive developer supply member rotatably supported while being partially in contact with the developer carrier 1, and a developer. Through developer carrier 1
A regulating plate 3 which is a regulating member which is in pressure contact with and at least a portion in contact with the developer carrying member 1 is made of a conductive fibrous member and forms a thin layer of the developer on the developer carrying member 1 and charges the developer. A stirring paddle 5 that stirs the developer T in the developer supply unit; a leakage prevention cover 6 that prevents the developer T from leaking from the upper portion of the developer carrier 1; A developing tank container 7 forming a developer supply portion to be housed and a power source E1 connected to the porous conductive elastic member 2.
A power source E2 connected to the regulation plate 3 and the developer carrier 1
The main part of the power source E3 is connected to the power source E3.

The developer carrying member 1 is made of aluminum, stainless steel,
A metal roller made of nickel or the like is usually used, but it is also possible to use a roller having a conductive resin layer formed on the surface. In this case, it is possible to improve the halftone reproduction and reduce the deflection accuracy of the developer carrying member. The conductive resin used is phenol resin, urea resin, acrylic resin or the like in which conductive carbon is dispersed, and has a specific resistance of 1
A layer with a thickness of 0 ³ to 10 ¹² Ωcm and a thickness of 1.5 to 5 mm is formed.

The porous conductive elastic member 2 is made of a material such as soft polyurethane foam having a three-dimensional skeletal structure containing conductive carbon, graphite, conductive resin, etc., and a conductive adhesive on the metal shaft. It is mounted in roll form. The electric resistance is about 10 ³ to 10 ¹⁰ Ωcm. The porosity of the porous conductive elastic member 2 is preferably 15 or more and 45 or less per 25 mm as the number of cells (holes). Further, the contact depth (the amount of bite) of the porous conductive elastic member 2 to the developer carrying member 1 is the transportability of the developer T and the effect of removing the developer T remaining on the developer carrying member 1 after development. 0.5-1.0m from the perspective of
About m is experimentally good.

As described above, the regulation plate 3 serving as the regulation member is made of a conductive fibrous member at least in a portion in contact with the developer carrying member 1. The conductive fibrous member used here is not particularly limited as long as it is a conductive fibrous substance, and is, for example, a non-woven fabric, a cloth woven with regularity, or one obtained by subjecting electric flock to conductive treatment. Is preferably used. For example, a non-woven fabric or a cloth woven with regularity may be one that has been subjected to a conductive treatment by plating, a metal coat, or a conductive polymer coat. When electric flocking is used, electric flocking may be provided on the support and then conductive treatment may be performed.

Specifically, when a non-woven fabric is used, PET,
For non-woven fabrics made of PP, rayon, nylon, acrylic, etc., alone or in combination, Ni, Cu
A conductive non-woven fabric can be obtained by rendering it conductive by metal plating or coating such as or a conductive polymer coating containing a metal filler or carbon. For the production of the nonwoven fabric itself, the short fibers dispersed in water by the spinning method are dehydrated, dried and finished, and the raw material is formed into a web by ordinary spinning or special spinning such as the parallel method, and then melted, chemically and mechanically. Either a dry method of bonding by adhesion or entanglement may be used.

Even when a regular woven cloth is used, a cloth made of fibers based on a single material or a composite material of PET, PP, rayon, nylon, acrylic, etc. is similarly prepared as described above. It can be used by making it conductive as in the case of a non-woven fabric. When electric flocking is used, it is possible to use one in which electric flocking is provided on a support made of aluminum, stainless steel, nickel or the like, and then subjected to a conductive treatment with a metal coat or a conductive polymer coat.

The thickness of such a conductive fibrous member is usually 50 to 2000 μm, preferably 100 to 1000 μm, and the weight is 20 to 2 when it is adhered on a support.
It is 000 g / m ² , preferably 40 to 200 g / m ² . The fiber thickness of the conductive fibrous member is usually 0.1 to 1
The thickness is 00 μm, preferably 1 to 50 μm. If the thickness of the fiber is smaller than 0.1 μm, the contact portion to the developer carrying member becomes substantially flat, and if it is thicker than 100 μm, it becomes difficult to attach it to the support and the contact with the toner becomes difficult. The charge cannot be sufficiently given and the charge is insufficiently applied. The electrical resistance of the conductive fibrous member is preferably about 10 ³ to 10 ⁹ Ω as a volume resistance.

Specific examples of the regulating plate 3 having a conductive fibrous member are shown in FIGS. 2 (a) to 2 (f). (A) On the conductive elastic body 21 such as a metal plate or a rubber plate having conductive carbon dispersed or adhered thereto, a short conductive fibrous member 22 is provided at a portion in contact with the developer carrier via the developer. A regulation plate having one end formed in a brush shape and fixed by a conductive adhesive 23. (B) A regulating plate formed by fixing a conductive fibrous member 22 woven in a mesh shape or a lattice shape in the same manner as in (a) above. In this case, there is no particular problem even if it is attached to the entire surface on one side. (C) In the above (b), a regulation plate formed by covering the tip end portion thereof with the conductive fibrous member 22. In this case, both sides may be covered. (D) An example in which a conductive non-woven fabric is attached as the conductive fibrous member. (E) Although the base member of the regulation plate is insulative, this is an example in which the conductive film 24 is provided and the conductive fibrous member 22 is attached thereto or in a conductive state. (F) This is an example of a metal plate on which electric flocking 25 has been performed and then subjected to a conductive treatment.

The regulation plate 3 is not limited to these examples,
Brush, mesh, non-woven fabric only necessary materials,
Alternatively, a conductive fibrous member is fixed on one side or the entire surface, and the base member may be any of metal, conductive elastic material, and insulating material coated with a conductive film, and the power source E2 and the conductive fiber member are electrically connected. If not, it is not particularly limited. Further, the base member may be one that can satisfy the mechanical contact condition with the developer carrying member.

The stirring paddle 5 is not particularly limited in shape and the like, but has a shape which is effective for stirring and circulating the developer T in the developer supply section in the developing tank container 7, and the development. It is preferable that the retention portion or the agglomeration portion of the agent T is not formed. The leak prevention cover 6 is preferably formed of a thin urethane rubber plate or the like. The developer carrying member 1, the porous conductive elastic member 2, and the stirring paddle 5 are connected to each other outside the developing tank container 7 via a gear (not shown) so that they rotate simultaneously in the directions indicated by the arrows. Is becoming

On the other hand, around the photoconductor 4, a charging unit composed of a corotron or a scorotron for uniform charging, an exposure unit (not shown) by a laser scanning method for performing exposure according to image information, and the photoconductor 4 are provided. A transfer unit formed of a roller or a corotron for transferring the above developer image to a recording medium, a cleaning device for removing the developer T remaining on the photoconductor 4, and a discharge lamp for removing electric charges remaining on the photoconductor 4. Are arranged. The high-voltage power supplies E1, E2, E3 are connected to the porous conductive elastic member 2, the regulation plate 3, and the developer carrying member 1, respectively.

In the first developing device, the developer carrying member 1 is arranged so as to be in non-contact with the photoconductor 4, but in such a case, the toner flies to the surface of the photoconductor and develops.
It is also suitable for multicolor printing such as full color copying. Further, as in a second developing device to be described later, even if the thin layer of the developer on the developer carrying member 1 comes into close contact with the surface of the photosensitive member in order to increase the image density, they may face each other. Good. In the developing method of the present invention, since the surface of the photoconductor and the developer carrying member 1 are not in contact with each other or the thin layer of the developer is in contact with a weak pressure as described above, the toner is not pressured. The risk of breakage of the outer shell of the thermal dissociative capsule toner is greatly reduced, and the life of the developer can be greatly extended. Further, in the developing device used in the developing method of the present invention, since a large frictional force and pressure are not applied to the toner between the developer carrying member and the regulating member that regulates the layer thickness of the thin layer of the developer, the thermal dissociation type capsule is used. The risk of damage to the outer shell of the toner can be greatly reduced, and the life of the developer can be greatly extended.

Next, the operation of the first developing device thus constructed will be described. With the start of the operation of the developing process, the developer carrier 1, the porous conductive elastic member 2, and the stirring paddle 5 start to rotate in the directions indicated by the arrows. The developer T stored in the developer supply portion in the developing tank container 7 is porous due to the rotation of the porous conductive elastic member 2 when the rotation of the porous conductive elastic member 2 and the stirring paddle 5 starts. It is carried to the contact portion between the conductive elastic member 2 and the developer carrying member 1. Here, the developer T is charged by being charged by the porous conductive elastic member 2 connected to the power source E1.

The developer T, which has been charged with electric charge from the porous conductive elastic member 2, moves along with the rotation of the developer carrier 1 and the porous conductive elastic member 2, and a part of the developer T is blocked by the regulating plate 3.
A thin layer is formed on the developer carrying member 1 while being regulated to a thickness of about 0 to 40 μm, and an electric charge is applied from the regulating plate 3 to control a stable predetermined charge amount. This is a conductive fibrous member in which the portion of the regulation plate that is in contact with the developer carrying member is connected to the power source E2. Therefore, when the developer passes between the regulation plate and the developer carrying member, the fibrous member is formed. This is because the toner is in contact with, and the electric charge is applied from the power source E2 together with the triboelectric charge, and the electric charge is controlled to be more stable. In the conventional flat regulation plate, the contact area with the developer was limited, so even if it is a conductive regulation plate that is connected to the power supply, the developer with a stable charge amount does not carry the regulation plate and the developer. Only the developer on the regulation plate side of the developer layer between the bodies was used. However, in the present invention, the contact area with the developer is increased by using the conductive fibrous member, and it is possible to contact with more developer,
The charge amount can be stabilized. This stabilizes the developability and reduces dust and scumming. The adhesive force between the developer carrier 1 and the developer T at this time is a mirror image force between the electric charge of the developer T and the metallic developer carrier 1.

The thin layer of the developer T formed on the developer carrying member 1 is carried to the developing area to develop the photosensitive member 4 on which the electrostatic latent image is formed, as the developer carrying member 1 rotates. It faces the photoconductor 4 with a distance of the gap g (thin layer thickness of the developer T). A power source E3 is connected to the developer carrying member 1, and since the surface charge densities of the image portion and the non-image portion of the electrostatic latent image on the photosensitive member 4 are different in the developing area, the developer T , And the electric field at the position of the developing area is E, the force F = qE acting on the developer T is different between the image portion and the non-image portion of the electrostatic latent image, and the developer is present only in the image portion. T flies from the developer carrying member 1 to the side of the photosensitive member 4 and migrates, and development is performed.

The developer T on the developer carrying member 1 which has not been used for development is stored in the developer supplying portion in the developing tank container 7 with the rotation of the developer carrying member 1 so as to be stored again in the leak preventing cover 6. Is conveyed in the direction. The leakage prevention cover 6 is in contact with the developer carrying member 1, but is in soft contact therewith,
Moreover, since the developer T hits the curved portion, the developer T is guided by the leakage prevention cover 6 into the developing tank container 7 without being stripped from the developer carrier 1.

The developer T remaining on the developer carrying member 1 guided into the developing tank container 7 is conveyed toward the porous conductive elastic member 2 and developed by the porous conductive elastic member 2. The porous conductive elastic member 2 scraped off from the agent carrier 1
Is carried to the stirring paddle 5 in the developing tank container 7 with the rotation. Therefore, the developer T is circulated and stirred in the developing tank container 7 to contribute to the development again.

The power sources E1, E2 and E3 are usually 300 to 900 V in absolute value. For example, in the case of negative polarity reversal development, E1 = -600 V, E2 = -400 V, E3 =-.
By setting the voltage to 500 V, relatively good developing conditions can be obtained. By repeating the above operation, the development process proceeds. Further, as the power source E1, not only a direct current but also an alternating current may be superposed for preventing the aggregation of the developer, improving the transportability, and stabilizing the environment. Further, the power source E2 also improves the charging property of the developer, and it is effective to superimpose an alternating current here for environmental stability. By superimposing an alternating current also on the power source E3, the resolution can be improved and the image density can be further improved. This is realized by the reciprocating motion of the developer between the developer carrying member of the developer and the electrostatic latent image on the photosensitive member.

Furthermore, the development conditions can be controlled by controlling the voltage applied to each part, and even when environmental changes, developer changes, electric resistance changes of these constituent members, lot variations, etc. occur. The level of image density can be adjusted by controlling the applied voltage. For example, in order to control the developing electric field between the photoconductor and the developer bearing member, a signal from a surface potential sensor mounted near the surface of the photoconductor before development can be used to control the environment such as temperature and humidity. A sensor, a humidity sensor, or the like can be mounted and the applied voltage can be controlled by signals from these. In particular, it is effective to control the voltage applied to each of the developer carrier and the conductive fibrous member. The latent image potential change may be measured by a surface potential sensor, and the applied voltage to the developer carrying member corresponding to the variation may be changed and controlled.

With the consumption of the developer T, the developing tank container 7
When the developer T is replenished to the developer supply section in the inside, it can be done by opening the supply lid 7a or by a cartridge. In the developer supply portion in the developing tank container 7, the residual developer T is used as the developer T.
And unused developer T are mixed, but all of the developer T that contributes to adhesion to the photoconductor 4 undergoes contact and conveyance by the porous conductive elastic member 2 and the regulation plate 3, so that charge is imparted there. The charge amount is controlled by the charge amount, and the charge amount is stable regardless of the history of the developer T until then. This stabilizes the image as the flight force F = qE of the developer T to the image portion, which is most important for development, is stabilized.

FIG. 3 is a schematic view showing another aspect of the developing device used in the present invention (hereinafter abbreviated as the second developing device). Here, a fibrous conductive member 8 formed in a brush shape is used as the conductive developer supply member, and it is very close until a thin layer of the developer on the developer carrier 1 comes into contact with the surface of the photoconductor. The regulation member is formed in a rotatable roller shape (roller-shaped regulation member 9). Further, the rotation axis of the developer carrier is opposite to that of the first developing device,
In addition, the rotation direction of the developer carrier is also changed. A partition plate 10 is also provided to prevent the supply of uncharged toner and the like to the developing area.

The brush-like fibrous conductive member 8 as the conductive developer supplying member is, for example, a conductive resin fiber such as nylon or rayon in which conductive carbon is dispersed, or a layer of a conductive substance in the center. It is formed in the shape of a brush from conductive resin fibers such as nylon and rayon that are provided with. Regarding the conductivity of the fibers, there is also a method of making the conductive carbon or the like into fine particles and attaching it to the surface to make the fibers conductive. Like the porous conductive elastic member 2 used in the first developing device, the fibrous conductive member 8 is formed in a brush shape on a rotatable metal shaft supported by the wall of the developing tank container 7. ing. To bond the fibrous conductive member 8 to the metal shaft, a conductive adhesive similar to that used for the porous conductive elastic member 2 is used.

As the developer carrying member 1, a member similar to the porous conductive elastic member used as the conductive developer supplying member in the first developing device from the viewpoint of the developing electrode effect is electrically conductive on the metal shaft. What was formed by adhering with an adhesive agent etc. can be used. In this case, in order to prevent the permeation of the toner into the porous material, one having a small cell diameter or one having a thin dielectric film formed on the surface is used. As the layer forming the surface of the developer carrying member, not only such a porous material but also a fibrous material or a flexible thin material may be used.

The roller-shaped regulating member 9 is formed by cylindrically forming a part of the conductive fibrous member shown in the first developing device in a portion in contact with the developer carrying member. is there. The roller-like member increases the surface area of the conductive fibrous member as compared with the flat plate-like restricting member, and by positively repeating contact with this member, the developer is given an electric charge and a more stable charge amount is obtained. Also, the power source E
1, E2, and E3 are connected to the fibrous conductive member 8, the roller-shaped regulating member 9, and the developer carrying member 1, respectively.

The operation of the second developing device will be described. Similar to the first developing device, the fibrous conductive member 8 imparts an electric charge and the charged developer is carried to a position in contact with the roller-shaped regulating member 9 as the developer carrier 1 rotates. Here, the layer thickness of the developer is regulated by the roller-shaped regulating member 9 which is connected to the power source E2 and is formed of a conductive fibrous member on the surface, and the conductive fibrous member of the roller-shaped regulating member 9 is positively activated. By repeating the contact, the developer is given a charge and the charge amount becomes more stable. The adhesive force between the developer and the developer carrier here is mainly an electrostatic force between the charge of the developer and the developer carrier.

The developer is carried to the developing area as the developer carrying member 1 rotates and comes into contact with the photoconductor, and the developer carrying member 1 connected to the power source E3 is subjected to an electric field between the electrostatic latent images on the photoconductor surface. Then, it adheres to the image area and is developed. After that, the same operation as that of the first developing device is performed, and the developing process proceeds.

The voltages applied to the power sources E1, E2 and E3 are the same as in the first developing device. Further, superimposing not only direct current but also alternating current as a power source is effective as in the case of the first developing device. Further, similarly, the developing conditions can be controlled by controlling the voltage applied to each part, and even if environmental fluctuations, developer fluctuations, electric resistance fluctuations of these constituent members, lot variations, etc. occur, they are stable. Development can be performed. Further, it goes without saying that the present invention can be carried out regardless of the charge polarity of the developer and regular development / reverse development.

As described above, in the developing method of the present invention, the thermal dissociative capsule toner, which is the developer supplied to the developer carrier by the conductive developer supplying member to which a high voltage is applied, is charged. In the regulating member according to the invention, the portion abutting on the developer carrying member is made of a conductive fibrous member and a high voltage is applied, so that the layer of the developer on the developer carrying member is formed by the regulating member. By controlling the thickness to form a thin layer and applying the electric charge from the conductive fibrous member, the thermal dissociation type capsule toner, which is the developer in the present invention, is more uniformly charged and stabilized. Further, the developer carrier to which a high voltage is applied conveys the developer whose charge is stabilized by the above to the electrostatic latent image forming body side, and the electrostatic latent image part potential on the electrostatic latent image forming body is conveyed. Development is performed by causing the developer to migrate in an electric field between the surface potential of the developer carrier and the surface potential of the developer carrier. Further, in the developing method of the present invention, the developing conditions can be controlled by controlling the voltage applied to each part, and can be used stably against environmental changes, changes in the thermal dissociative capsule toner that is the developer, and the like. it can.

[0068]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Production Example 1 Production Example of Thermal Dissociation Capsule Toner 70.0 parts by weight of styrene, 2-ethylhexyl acrylate
30.0 parts by weight, divinylbenzene 1.0 part by weight, carbon black "# 44" (manufactured by Mitsubishi Kasei) 10.0 parts by weight, 2,2'-
4.0 parts by weight of azobisisobutyronitrile and 9.5 parts by weight of 4,4'-diphenylmethane diisocyanate "Millionate MT" (manufactured by Nippon Polyurethane Industry Co., Ltd.) were added, and the mixture was put into an attritor (manufactured by Mitsui Miike Kakoki) and heated to 10 ° C. And dispersed for 5 hours to obtain a polymerizable composition. 30% by weight of this in 800 g of an aqueous colloidal solution of 4% by weight of tricalcium phosphate prepared in a glass separable flask having a volume of 2 liters.
Was added and the mixture was emulsified and dispersed for 2 minutes at 5 ° C. and a rotation speed of 10,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.). A four-neck glass lid was attached, a reflux type cooling tube, a thermometer, a dropping funnel with a nitrogen introducing tube, and a stainless steel stirring rod were attached, and the glass was placed in an electric heating mantle.
Resorcin 22.0 g, diethyl malonate 3.6 g, 1,4-diazabicyclo [2.2.2] octane 0.5 g, ion-exchanged water 40 g
Prepare a mixed solution of and mix with a dropping funnel while stirring.
It dripped over minutes. Then, while continuing stirring under nitrogen, the temperature was raised to 80 ° C. and reacted for 10 hours. 10% after cooling
Dissolve the dispersant in aqueous hydrochloric acid, filter, wash with water, and then
The mixture was dried at 20 ° C. for 12 hours under reduced pressure at 20 mmHg and classified by an air classifier to obtain a heat-dissociable capsule toner having an average particle diameter of 9 μm and a resin having a heat-dissociative urethane bond. The glass transition point derived from the resin in the core material was 30.2 ° C, and the softening point was 130.0 ° C.

Production Example 2 Production Example of Thermal Dissociation Capsule Toner Copolymer 10 comprising 75 parts by weight of styrene and 25 parts by weight of n-butyl acrylate and having a softening point of 75.3 ° C. and a glass transition point of 40.5 ° C.
0 Parts by weight of copper phthalocyanine “Suikaprint Cyanine Bl
ue GN-O "(Sumitomo Chemical Co., Ltd.) 6 parts by weight and polypropylene wax" Bi- scol 550p "(Sanyo Kasei Co., Ltd.) 5 parts by weight are premixed, melt-kneaded by a twin-screw extruder, and cooled. Then, it was crushed. 40 parts by weight of this kneaded product, 50 parts by weight of styrene, 15 parts by weight of n-butyl acrylate, 2,2'-
3 parts by weight of azobis (2,4-dimethylvaleronitrile),
Adduct of 3 moles of 2,4-tolylene-diisocyanate and 1 mole of trimethylolpropane "Takenate D-102"
(Takeda Pharmaceutical Co., Ltd.) 9.0 parts by weight, xylylene-1,4-
The mixture was mixed with 0.5 part by weight of diisothiocyanate to obtain a polymerizable composition. 4% by weight of tricalcium phosphate prepared in advance in a glass separable flask having a volume of 2 liters.
The amount of 30% by weight was added to 800 g of the aqueous colloidal solution of and the rotation speed was 10,000 rpm at 5 ° C using the TK homomixer.
And emulsified and dispersed for 2 minutes.

A four-necked glass lid was attached, a reflux type cooling tube, a thermometer, a dropping funnel with a nitrogen introducing tube, and a stirring rod made of stainless steel were attached, and the glass was installed in an electric heating mantle. Four
-Acetylcatechol 27.4 g, dimethyl malonate 4.0 g,
A mixed solution of 0.8 g of 1,2-ethanedithiol, 0.5 g of 1,4-diazabicyclo [2.2.2] octane and 40 g of ion-exchanged water was prepared and added dropwise from a dropping funnel over 30 minutes while stirring. Then, while continuing stirring under nitrogen, the temperature was raised to 80 ° C. and reacted for 10 hours. After cooling, dissolve the dispersant in 10% aqueous hydrochloric acid, filter, wash with water, dry under vacuum at 20 mmHg for 12 hours at 45 ° C, classify with a wind classifier, and heat the outer shell with an average particle size of 9 μm. A heat dissociative capsule toner made of a resin having a dissociative urethane bond was obtained. To 100 parts by weight of this heat dissociative capsule toner, 0.4 parts by weight of hydrophobic silica fine powder "Aerosil R-972" (manufactured by Aerosil Co., Ltd.) was added and mixed to obtain a capsule toner according to the present invention. The glass transition point derived from the resin in the core material is 35.4 ° C, and the softening point is
It was 133.5 ° C.

Example 1 A laser printer using a commercially available selenium-arsenic photoconductor was used in a modified manner by replacing the developing device with a developing device conforming to the above-mentioned first developing device. The peripheral speed of the developer carrier is 80 m
Development was performed at m / sec. As a result, no deterioration of the image was observed even after continuous output of 30,000 sheets of A4 paper, and good quality image was obtained. The gap g of the developing device used here was 80 μm, and a conductive non-woven fabric was used as the conductive fibrous member used in the portion of the regulating member that abuts the developer carrying member. Also, E1, E2,
The applied voltage of E3 is + 800V, + 400V,
It was + 500V.

Example 2 Obtained in Production Example 2 using a modified apparatus in which the developing apparatus of a laser printer using a commercially available selenium-arsenic photoconductor is replaced with the developing apparatus according to the first developing apparatus described above. Using the thermally dissociative capsule toner, development was performed at a peripheral velocity of the developer carrying member of 50 mm / sec in the same manner as in Example 1. As a result, even after continuous output of 20,000 sheets of A3 paper, no image deterioration was observed and good quality image was obtained. The developing device used here had a gap g of 80 μm, and the conductive fibrous member used for the portion of the regulating member that abuts the developer carrying member was a regular woven cloth made of rayon. I used a thing. The applied voltages of E1, E2, and E3 are + 800V, + 400V, and +50, respectively.
It was 0V.

[0073]

According to the developing method of the present invention, the supply of the developer, the charging, the thin layer formation, the conveyance to the developing zone, and the control of the flight force, which are important in forming the development process by the one-component developer, are controlled. It has a function of removing, stirring, and circulating. In particular, the portion abutting the developer carrying member is a regulating member constituted by a conductive fibrous member connected to a power source, thereby regulating the layer thickness of the developer layer on the developer carrying body, The thermal dissociation type capsule toner used in the present invention is also sufficiently charged, and the stable and uniform charge amount of the developer is charged. Therefore, there is an effect that it is possible to stably form an image having high resolution and high resolution without dust and scumming.

Also, in terms of environmental characteristics, the present invention does not use the triboelectric charging method that greatly affects the surrounding environment and the surface condition of the material, and therefore has the effect of exhibiting stable characteristics. Furthermore, by controlling the voltage applied to each part, the development conditions can be controlled, and even when environmental changes, developer changes, electric resistance changes of these components, lot variations, etc. occur, each applied voltage can be controlled. By doing so, it is possible to adjust the image density levels. The regulating member according to the present invention has an advantage that the conductive fibrous member that has been subjected to the conductive treatment can be easily attached to the metal plate or the conductive elastic body by adhesion or the like, so that the cost can be reduced. Also,
In the developing method of the present invention, the toner surface is not in contact with the developer carrier, or only the thin layer of the developer is in contact with the developer carrier with a weak pressure. Since the risk of damage to the outer shell of the capsule toner is greatly reduced, the life of the developer can be greatly extended.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of an image recording apparatus provided with a first developing device.

FIG. 2 is a schematic view of a regulating member used in the developing device according to the present invention.

FIG. 3 is a schematic diagram showing a configuration of an image recording apparatus provided with a second developing device.

FIG. 4 shows a schematic view of a conventional developing device.

[Explanation of symbols]

 1 Developer Carrier 2 Porous Conductive Elastic Member 3 Regulation Plate 4 Photosensitive Member 5 Stirring Paddle 6 Leak Prevention Cover 7 Developing Tank Container 8 Fibrous Conductive Member 9 Roller Regulation Member 10 Partition Plate

Claims (7)

[Claims] 1. A one-component developing method for developing a latent image on an electrostatic latent image forming body using a heat dissociative capsule toner,
A developing device provided with a developer carrying member carrying at least a developer, and a restricting member for restricting the layer thickness of a thin layer of the developer formed on the developer carrying member and for giving an electric charge to the developer. And using a device in which the portion of the regulating member that is in contact with the developer carrying member is made of a conductive fibrous member, and applying a voltage to each of the developer carrying member and the conductive fibrous member. And a developing method. 2. The main component of the shell material of the heat dissociative capsule toner is composed of a resin having at least one bond of a heat dissociable urethane bond, a thiol urethane bond, or an s-thiourethane bond. Item 1. The developing method according to Item 1. 3. The heat dissociable urethane resin, which is the main component of the shell material according to claim 2, has a phenolic hydroxyl group and / or a thiol group among bonds involving all isocyanate groups and / or isothiocyanate groups. The developing method according to claim 2, wherein the number of bonds by the reaction with is 30% or more. 4. The softening point of the heat dissociative capsule toner is 8
The developing method according to claim 1, wherein the temperature is from 0 ° C to 150 ° C. 5. The developing method according to claim 1, wherein the conductive fibrous member is a brush-shaped conductive fibrous substance. 6. The developing method according to claim 1, wherein the conductive fibrous member is a non-woven fabric obtained by conducting a conductive treatment, a cloth woven with regularity, or electric flocking. 7. The developing method according to any one of claims 1 to 4, wherein an apparatus provided with a control means for controlling a voltage applied to each of the developer carrier and the conductive fibrous member is used.