JPH1010781A - Surface treatment of thermoplastic resin particle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve or control a fluidity and electrification property of a toner and to improve a developing property and reliability of a developing system by immediately heating a mixture of thermoplastic particles and additives. SOLUTION: A mixture of thermoplastic particles or toner particles and additives, namely, a sample 4 is carried from a quantitative supply device 5 through an inlet tube 6 with a specified amt. of pressurizing air and is sprayed into the hot air flow 8 through sample spray nozzles 7 disposed around a hot air spray nozzle 3. The sample particles 9 sprayed are immediately heated by the hot air at high temp, thereby changing the sample particles having an irregular shape into a spherical shape. Moreover, by subjecting the particles with additives depositing on the particle surfaces to instant surface heat treatment at one time, the additives are embedded in the particle surface and firmly deposit. Therefore, compared to a conventional pulverizing method or wet method, the fluidity and electrification property can be rapidly and precisely controlled, which improves the reliability and life of the toner.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment method for thermoplastic resin particles, and more particularly to a method for producing a developer used in an electrophotographic printing apparatus capable of recording high definition and high image quality.

[0002]

2. Description of the Related Art To cope with high image quality of electrophotographic copying machines and printers, it is essential to reduce the particle size of toner. Mix constituent materials such as resin, colorant and charge control agent
In the conventional dry pulverization method, which is performed by pulverization and classification after melt-kneading, various problems such as a decrease in fluidity and a non-uniform charging property are caused by the reduction in particle size. These problems are attributable to the dispersion state of each constituent material in the toner particles, and it is difficult to achieve further uniform dispersibility by the conventional pulverization method. As a means for solving this problem, a method for producing toner particles is a wet granulation method such as a suspension polymerization method. Further, a method has been proposed in which a material that affects the fluidity and chargeability is added to the surface of the toner particles in a dry or wet manner.

However, in the former wet granulation method, impurities such as a surfactant and a polymerization catalyst used at the time of polymerization and granulation remain in the toner after granulation, and adversely affect charge control and the like. In addition, in the latter addition method, solvent removal /
New problems such as an increase in the size of the apparatus due to the recovery, and desorption due to insufficient adhesive strength of the additive are caused.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner particle surface capable of easily improving or controlling the fluidity and chargeability of a toner to improve development characteristics and reliability of a development system. It is to provide a processing method.

[0005]

The gist of the present invention to achieve the above object is as follows.

(1) Means for preparing particles having a predetermined particle size range containing a thermoplastic resin, means for mixing the thermoplastic particles and an additive, and a softening temperature Sp + of the thermoplastic resin
A thermoplastic resin having means for instantaneously heating a mixture of the thermoplastic particles and the additive in an atmosphere in a temperature range of 0 ° C. to + 300 ° C., and means for cooling and collecting the heat-treated mixture; Surface treatment method for particles.

(2) Means for producing particles of a predetermined particle size range made of at least a thermoplastic resin is a means for producing particles by a pulverization method comprising steps of mixing, melt-kneading, pulverizing, and classifying constituent materials. Surface treatment method for plastic resin particles.

(3) The means for preparing particles of a predetermined particle size range made of at least a thermoplastic resin is a means for preparing particles by a wet granulation method in which a constituent material is dissolved in a solvent and then granulated by suspension. Surface treatment method for plastic resin particles.

(4) The additive to be mixed with the thermoplastic particles is
A surface treatment method for thermoplastic resin particles containing at least one of four substances: a substance having coloring ability, a substance having charge control ability, a substance having fluidity control ability, and a magnetic substance.

(5) Thermoplastic containing at least one of the following four substances: a substance having coloring ability, a substance having charge controlling ability, a substance having fluidity controlling ability, and a substance having magnetic force in thermoplastic particles. Surface treatment method for resin particles.

According to the present invention, in order to achieve the above object, the surface of the thermoplastic resin particles or toner particles is instantaneously exposed to a high-temperature atmosphere to temporarily melt the surface of the toner particles, and the surface tension of the toner particles causes the shape of the toner particles to be reduced during cooling. Spherify.
Further, at that time, a fluidizing agent, a coloring agent, a charge controlling agent, and the like are added, so that the additives are uniformly and firmly adhered to the surface of the thermoplastic resin particles or the toner particles.

Therefore, finer fluidity and chargeability can be more quickly controlled as compared with the conventional pulverization method and wet method, and the reliability and life of the toner can be improved.

In the surface treatment method according to the present invention, an additive is added in the post-treatment after producing the thermoplastic resin particles or the toner particles, and the shape of the toner, the amount of the additive, and the like can be easily determined.
The distribution can be controlled, and the heat treatment is performed during the external addition process, so that the adhesive force of the additive to the surface of the toner particles can be increased as compared with the conventional method.

It is not necessary to use special means for each of the above-mentioned means, that is, a means for preparing particles of at least a predetermined particle size range made of a thermoplastic resin, and a means for mixing the thermoplastic particles with an additive. Absent.

As a means for preparing particles of at least a predetermined particle size made of a thermoplastic resin, a dry pulverization method, a wet granulation method, and the like, which are conventionally used as a method for producing toner particles, can be used. The dry pulverization method is a method in which materials constituting toner particles are mixed, melt-kneaded, and then pulverized and classified to obtain toner particles, and is currently the most common method for producing toner particles. Further, the wet granulation method may include a polymerization step such as a suspension polymerization method or an emulsion polymerization method, or may be a granulation method not including a polymerization step such as a suspension granulation method. In addition, a soap-free emulsion polymerization method, a microcapsule method, a non-aqueous dispersion polymerization method, or the like may be used.

The average particle size of the thermoplastic resin particles or toner particles produced by such a method is 1 to 15 μm,
In particular, the thickness is preferably 2 to 10 μm. If the particle diameter of the thermoplastic resin particles or the toner particles is smaller than this range, the hiding power on paper cannot be obtained, and if it is larger than this range, the image becomes coarse and high definition cannot be obtained. Further, among the above various methods, the thermoplastic resin particles or toner particles obtained by the wet method are dried by a known drying device.

The means for mixing the thermoplastic particles or toner particles with the additives may be a turbulence mixer, a Henschel mixer, a V blender or the like which has been conventionally used as a method for externally adding toner particles to the surface. Mixing methods are available.

The thermoplastic resin constituting the thermoplastic resin particles or the toner particles that can be treated according to the present invention is not particularly limited as long as it is generally used as a binder in toner particles. For example, homopolymers of styrene such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene and substituted products thereof, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer,
Styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-methyl methacrylate copolymer Polymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer Copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-
Styrene copolymers such as indene copolymer, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, silicone resin, polyester resin, polyurethane resin, polyamide resin, epoxy resin, polyvinyl butyral, rosin-modified resin, terpene resin, phenol Resin, xylene resin, aliphatic or alicyclic hydrocarbon resin,
Aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like are used alone or in combination.

Further, the colorant constituting the thermoplastic resin particles or the toner particles which can be treated according to the present invention, or the colorant which is mixed after the particles are formed, is usually added as a substance which controls the color developing ability in the toner particles. There is no particular limitation as long as it is widely used as an agent. For example, C.I. I. Direct Black 19, C.I.
Direct Black 154, CI Food Black 2,
CI Acid Yellow 23, CI Acid Red 8
7, CI Acid Red 35, CI Acid Blue 9, CI Direct Blue 86, and the like, as well as carbon black, nigrosine, as well as coloring agents which have been often used as coloring agents for inkjet inks. In addition to dyes,
Azo dyes (for example, CI Solvent Yellow 2, 1
4, 16, 19, 60, CI Solvent Red 3,
8, 24, 27), dyes such as anthraquinone dyes, indico dyes, phthalocyanine dyes, xanthene dyes (for example, CI Solvent Red 48, 49), and azo-based face amounts (for example, CI Pigment Yellow) 12, CI
Pigment Red 48, 81, CI Pigment Green 4), benzimidazolone-based face amount (for example, CI Pigment Red 185), quinacridone-based face amount (for example, CI Pigment Red 122, 207, 209) , Phthalocyanine face amount (for example, CI Pigment Blue 1)
5, CI Pigment Green 7), isoindolinone-based face amount (for example, CI Pigment Yellow 109, 17)
3), isoindoline-based face amount (for example, CI Pigment Yellow 139), dioxazine-based face amount (for example, CI.
Pigment violet 23), anthraquinone-based face amounts (for example, CI Pigment Yellow 108, CI Pigment Red 177, CI Pigment Blue 6), and perylene-based face amounts (for example, CI Pigment Red 17).
8), perinone-based face amount (for example, CI Pigment Orange 43), thioindico-based face amount (for example, CI Pigment Violet 38), quinophthalone-based face amount (for example, CI Pigment Yellow 133), metal complex Organic face quantity such as systematic face quantity (for example, CI Pigment Yellow 153), inorganic face quantity such as titanium oxide, carbon black, molybdenum red, chrome yellow, titanium yellow, chromium oxide, Berlin blue, and aluminum Known dyes and pigments such as metal powders such as powders can be used as colorants.

Further, the charge controlling agent constituting the thermoplastic resin particles or the toner particles which can be treated according to the present invention, or the charge controlling agent mixed after forming the particles, is usually added as a substance which controls the charging ability of the toner particles. There is no particular limitation as long as the charge control agent is widely used. The charging polarity may be either positive or negative, and the amount of addition is appropriately selected depending on the type of toner, additives and binder, and the toner developing method. The charge control agent is, for example, a metal complex of alkyl salicylic acid, a metal complex of dicarboxylic acid for negative charging,
Examples include polycyclic salicylic acid metal salts, azo metal dyes, chlorinated paraffins, chlorinated polyesters, and the like. For positive charging, a nigrosine dye, an aliphatic metal salt, a quaternary ammonium salt, a benzothiazole derivative, a guanamine derivative, dibutyltin oxide, or the like can be used. These charge control agents are used alone or as a mixture of two or more.

Further, a substance having a fluid controllability capable of forming thermoplastic resin particles or toner particles which can be processed according to the present invention, or a substance having a fluidity controllable ability to mix the particles after the particles are formed, is usually a toner. The material is not particularly limited as long as it is widely used as a substance that controls the flow performance of particles. For example, fluidizing agents such as silica, aluminum oxide, titanium oxide, and magnesium fluoride; non-magnetic inorganic fine particles particularly hydrophobicized such as silicon carbide, boron carbide, titanium carbide, and zirconium carbide; styrene (meth) acrylic; Various organic fine particles such as Teflon, silicone, polyethylene, and polypropylene may be used.

Further, a substance having a magnetic force constituting the thermoplastic resin particles or the toner particles which can be processed by the present invention, or a substance having a magnetic force which is mixed after the particles are formed, is generally used as a substance which controls the magnetic force in the toner particles. There is no particular limitation as long as it is satisfied. For example,
Metal powders such as iron, manganese, nickel and cobalt,
Ferrites such as iron, manganese, nickel, cobalt, and zinc are available. The average particle size of the powder is preferably 1 μm or less, particularly preferably 0.6 μm or less.

Further, other additives such as an anti-offset agent may be added to the thermoplastic resin particles or toner particles that can be treated according to the present invention, for example, to improve the fixability.

Next, the thermoplastic resin particles or toner particles granulated in a predetermined particle size range are jetted into a heated air stream to perform an instantaneous surface heating treatment. The temperature of the heated gas stream is usually in the range of the softening temperature of the particles Sp + 0 ° C. to + 300 ° C., and is preferably set to a temperature at which the constituents in the particles do not decompose. Further, when thermoplastic resin particles or toner particles are produced by a wet granulation method, the temperature is preferably set to a temperature equal to or higher than the decomposition temperature of impurities such as a surfactant and a polymerization initiator remaining in the particles. Suitable conditions for the instantaneous surface heat treatment also depend on the particle size of the thermoplastic resin particles or toner particles, and it is necessary to lower the treatment temperature as the average particle size decreases.

By performing such an instantaneous surface heating treatment, the surfaces of the thermoplastic resin particles or the toner particles are instantaneously melted, and the irregularly shaped particles are made spherical. At the same time, a substance having coloring ability on the particle surface,
Instantaneous surface heating treatment with additives such as substances having charge control ability, substances having fluidity control ability, and substances having magnetic force attached to the surface, and the additives are embedded on the particle surface and adhere firmly I do. In addition, by adjusting and controlling the processing temperature of the instantaneous surface heat treatment and the supply amount of particles or a mixture of particles and additives into a hot air stream, the degree of spheroidization of particles or the degree of embedding of additives is controlled. , The intensity can be controlled. It should be noted that the conditions for these instantaneous surface heat treatments are naturally selected as appropriate according to the particle size, particle size distribution, specific gravity, and thermal characteristics of the particles constituting the particles.

The thermoplastic resin particles or toner particles subjected to the instantaneous surface heat treatment are preferably cooled. By cooling, adhesion of particles to the inner wall of the apparatus and aggregation of particles are less likely to occur, and the yield after treatment is improved.
Even if the particles are uniformly treated as single particles during the instantaneous surface heating treatment, thermal aggregation occurs unless cooling treatment is performed. The temperature of the cooling treatment is appropriately selected depending on the particle size, particle size distribution, specific gravity, and thermal characteristics of the particles constituting the particles.
Specifically, the temperature of the thermoplastic resin particles or toner particles needs to be lower than the glass transition temperature of the particles.

Next, the instantaneous surface heating treatment and the cooling treatment in the present invention will be specifically described with reference to FIG. Note that these processing methods in the present invention are not limited to the processing method shown in FIG. 1, and other methods and apparatuses may be used as long as they satisfy the same processing conditions.

The high-temperature and high-pressure air adjusted by the hot-air generator 1 is injected from the hot-air injection nozzle 3 through the introduction pipe 2.
On the other hand, a mixture of thermoplastic particles or toner particles and an additive, that is, a sample 4 is conveyed from a fixed amount supply device 5 by a predetermined amount of pressurized air through an introduction pipe 6 and is provided by a sample injection nozzle provided around a hot air injection nozzle. 7 is injected into the hot air flow 8. The injected sample particles 9 are instantaneously heated by high-temperature hot air. As a result of the instantaneous surface heating, the shape of the amorphous sample particles is made spherical.
At the same time, by performing an instantaneous surface heating treatment with the additive attached to the particle surface, the additive is embedded on the particle surface and adheres firmly.

Next, the sample particles subjected to the instantaneous surface heating treatment are immediately introduced from the sample introduction hood 10 into the introduction tube 11. At that time, since the sample particles are introduced together with the outside air 12, that is, the cooling air, the temperature of the sample particles is cooled to the glass transition temperature or lower as described above. Next, the sample particles are collected by the cyclone 13 through the introduction tube, and accumulate in the collection bottle. The transport air after the toner is collected is further passed through a bag filter (not shown) to remove fine powder, and then discharged to the atmosphere via a blower (not shown). In the surface treatment method of the present invention, the surface of the thermoplastic resin particles or toner particles is instantaneously exposed to a high-temperature atmosphere to temporarily melt the surface of the toner particles, and the surface tension thereof forms a spherical shape upon cooling. By adding a fluidizing agent, a colorant, a charge control agent, and the like, the additives can be uniformly and firmly adhered to the surface of the thermoplastic resin particles or the toner particles.

Accordingly, fine fluidity and chargeability can be controlled more quickly than in the conventional pulverization method and wet method, and the reliability and life of the toner can be improved.

In the surface treatment method according to the present invention, the additives are added in the post-treatment after producing the thermoplastic resin particles or the toner particles, and the shape of the toner, the amount of the additives, and the like can be easily determined.
This is because the distribution can be controlled and the adhesive force of the additive to the surface of the toner particles can be increased as compared with the conventional method because heat treatment is performed during the external addition treatment.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically based on embodiments. In the following Examples and Comparative Examples, the evaluation method of the toner samples was as follows: bulk density, average particle size,
It is a weight charge amount and a filming test. The non-magnetic one-component developing machine shown in FIG. 2 was used for the weight charge amount and the filming test. The gravimetric charge amount was determined by measuring the charge amount and the attached weight of the toner on the developing roll. Further, the filming test is performed by filling the developing device with the toner and running idling.
After 4 hours, the presence or absence of toner filming on the developing roll and the blade was visually observed. Further, the actual printing test was performed using a color printer shown in FIG. 3 on which the developing machine shown in FIG. 2 can be mounted.

Comparative Example 1 Bisphenol polyester resin 100 parts by weight (Mw = 12,000, Mw / Mn = 8.9, Tg = 56 ° C., Tm = 100 ° C.) CI Pigment Blue 15 5.0 parts by weight CI Pigment Green 7 1.0 parts by weight Boron complex …………………………… ... 4.0 parts by weight Low molecular weight polypropylene 5.0 parts by weight The toner composition is premixed according to a conventional pulverization method. , Melt-kneading, coarse pulverization and fine pulverization were classified by a classifier to prepare a toner. The softening temperature of this toner was 100 ° C., and the average particle size was 7.3 μm.

Example 1 The toner particles obtained in Comparative Example 1 were subjected to 50 ° C., 100 ° C., 200 ° C., 300 ° C., 400
The toner particles were obtained by instantaneous surface treatment in a hot air stream at 450 ° C. and 450 ° C., respectively.

Table 1 shows the physical properties and evaluation results of the toner particles obtained in Comparative Example 1 and Example 1.

[0036]

[Table 1]

Referring to Table 1, the toner of Comparative Example 1 obtained by the pulverization method has low fluidity, and therefore has a low weight charge amount. Further, in the filming test, the toner was fused (filmed) to both the blade and the developing roll. Further, since the weight charge amount is low, fog often occurs in actual printing.

On the other hand, in the toner of the embodiment subjected to the instantaneous surface heating treatment, when the treatment temperature was 50 ° C., the effect of the heat treatment was not exhibited, and the result was almost the same as that of the untreated comparative toner. At a temperature of from 400 ° C. to 400 ° C., the fluidity was improved with an increase in the processing temperature, and as a result, the weight charge was also improved. Accordingly, a good, high-quality image was obtained even in actual printing.
Since the fluidity was further improved, no fusion of the toner was observed in the filming test. When the processing temperature was 450 ° C., when performing the instantaneous surface heating treatment, the toner particles were fused together in a hot air flow and could not be collected.

As described above, since the toner particles having an irregular shape only by pulverization have a small fluidity, when used as a non-magnetic one-component toner, a sufficient charge amount due to weight cannot be obtained. Fusion (filming) of the toner occurs. Further, by subjecting the toner particles to the instantaneous surface heat treatment according to the present invention, the particle shape can be made spherical and the fluidity can be improved, so that a sufficient weight charge amount can be obtained and the occurrence of toner filming can be suppressed. did it.

Example 2 Bisphenol polyester resin 100 parts by weight (Mw = 12,000, Mw / Mn = 8.9, Tg = 56 ° C., Tm = 100 ° C.) Low molecular weight Polypropylene 5.0 parts by weight The composition was premixed, melt-kneaded, coarsely pulverized according to the same toner production method as in Example 1 by the conventional pulverization method.
The finely pulverized product was classified by a classifier to prepare resin particles.
The softening temperature of the resin particles was 100 ° C., and the average particle size was 7.2 μm.

Further, the resin particles and the additive composition shown below were mixed in a Henschel mixer at room temperature at 10,000 rpm for 5 minutes to obtain a toner particle mixture. Further, the toner particle mixture was heated at 50 ° C., 100 ° C., 200 ° C. in the same manner as in Example 1 by using the instantaneous surface heating treatment and the cooling treatment shown in FIG.
The toner particles were obtained by instantaneous surface treatment in hot air flows of 300 ° C., 300 ° C., 400 ° C., and 450 ° C., respectively.

CI Pigment Blue 15: 5.0 parts by weight CI Pigment Green 7: 1.0 parts by weight Boron complex ... ............ 4.0 parts by weight The physical properties and evaluation results of the toner particles obtained in Example 2 are shown in Table 2.

[0043]

[Table 2]

As can be seen from Table 2, when the treatment temperature is 50 ° C., the additive composition is not sufficiently fixed to the resin particles, and furthermore, the shape of the particles themselves remains as an irregular shaped pulverized particle. Remained low, and as a result, the weight charge amount was low and a lot of fogging occurred even in actual printing, and a good image could not be obtained.

When the processing temperature is from 100 ° C. to 400 ° C., the shape of the particles themselves becomes more spherical as the processing temperature increases, and the fixation of the additive composition to the resin particles becomes stronger, and the fluidity and chargeability are improved. did. As a result, even in actual printing, although slight fogging was observed when the processing temperature was 100 ° C., good images could be obtained in other cases. Further, no filming occurred. When the processing temperature is 450 ° C., when performing the instantaneous surface heating processing,
The toner particles fused together in the hot air flow and could not be collected.

Example 3 Styrene monomer 90 parts by weight n-butyl methacrylate 10 parts by weight Low molecular weight polypropylene 5.0 parts by weight The above polymerizable monomer composition was dispersed and mixed with a homomixer to prepare a monomer composition. Thereafter, 112 g of the above monomer composition was placed in 400 ml of a 2% aqueous polyvinyl alcohol solution.
Was dissolved in 1.56 g of azobisisobutylnitrile, and the above monomer / composition was added. Thereafter, the polymerization reaction was carried out for 8 hours at a temperature in the flask of 70 ° C.

After completion of the polymerization, the mixture was cooled to room temperature, left standing overnight, filtered and dried to obtain resin particles. The softening temperature of the resin particles was 98 ° C., and the particle size was measured with a Coulter counter. As a result, the average particle size was 7.5 μm.

Further, the resin particles and the additive composition shown below were mixed in a Henschel mixer at room temperature in the same manner as in Example 2.
The mixture was mixed at 000 rpm for 5 minutes to obtain a toner particle mixture.
Further, the toner particle mixture was heated to 50 ° C. and 50 ° C. in the same manner as in Example 1 by using the instantaneous surface heating treatment and cooling treatment shown in FIG.
The toner particles were obtained by instantaneous surface treatment in hot air at 100 ° C., 200 ° C., 300 ° C., 400 ° C., and 450 ° C., respectively.

CI Pigment Blue 15 5.0 parts by weight CI Pigment Green 7 1.0 parts by weight Boron complex ……………………………………………………………………… ............ 4.0 parts by weight The physical properties and evaluation results of the toner particles obtained in Example 3 are shown in Table 3.

[0050]

[Table 3]

From Table 3, it was found that the treatment temperature was 5 as in Example 2.
At 0 ° C., since the additive composition is not sufficiently fixed to the resin particles, the fluidity remains low. As a result, the weight charge amount is low and a large amount of fogging occurs in actual printing, and a good image is obtained. Could not be obtained. Processing temperature is 100 ° C ~ 40
At 0 ° C., the fixation of the additive composition to the resin particles became stronger with an increase in the treatment temperature, and the fluidity and chargeability were improved. As a result, even in actual printing, although slight fogging was observed when the processing temperature was 100 ° C., good images could be obtained in other cases. Further, no filming occurred. When the processing temperature was 450 ° C., when performing the instantaneous surface heating treatment, the toner particles were fused together in a hot air flow and could not be collected.

[0052]

According to the present invention, means for preparing particles of at least a thermoplastic resin in a predetermined particle size range, means for mixing thermoplastic particles and additives, and softening temperature of thermoplastic resin Sp + 0 ° C. A thermoplastic treatment is performed using a surface treatment method having a means for instantaneously heating a mixture of thermoplastic particles and additives in an atmosphere in a temperature range of + 300 ° C. in a non-contact manner, and a means for cooling and collecting the heat-treated mixture. By instantaneously exposing the surface of the resin particles or toner particles to a high-temperature atmosphere, the surface of the toner particles is once melted, and the surface tension can make the shape spherical upon cooling. Further, at this time, by adding a fluidizing agent, a coloring agent, a charge control agent, and the like, the additives can be uniformly and firmly adhered to the surface of the thermoplastic resin particles or the toner particles.

Accordingly, fine fluidity and chargeability can be controlled more quickly than in the conventional pulverization method and wet method, and the reliability and life of the toner can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram of an instant surface heating apparatus according to the present invention.

FIG. 2 is an explanatory diagram of a non-magnetic one-component developing machine used for evaluating toner particles obtained by the present invention.

FIG. 3 is an explanatory diagram of a color printer used for evaluating toner particles obtained by the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Hot air generator, 2 ... Introduction pipe, 3 ... Hot air injection nozzle,
4 ... Sample, 5 ... Quantitative supply device, 6 ... Introduction tube, 7 ... Sample injection nozzle, 8 ... Hot air flow, 9 ... Sample particle, 10 ... Sample introduction hood, 11 ... Introduction tube, 12 ... Outside air, 13 ... Cyclone, 14 ... Collection bottle.

Claims (5)

[Claims] 1. A means for preparing particles of a predetermined particle size range containing a thermoplastic resin, a means for mixing said thermoplastic particles and an additive, and a softening temperature of the thermoplastic resin Sp + 0 ° C.
A means for instantaneously heating a mixture of the thermoplastic particles and the additive in an atmosphere in a temperature range of + 300 ° C. in a non-contact manner, and a means for cooling and collecting the heat-treated mixture. Surface treatment method for plastic resin particles. 2. Means for producing particles having a predetermined particle size range containing a thermoplastic resin includes mixing, melting, kneading, pulverizing,
2. The surface treatment method for thermoplastic resin particles according to claim 1, wherein the method is a particle preparation means by a pulverization method comprising each step of classification. 3. The means for producing particles of a predetermined particle size range containing a thermoplastic resin is a means for producing particles by a wet granulation method in which a constituent material is dissolved in a solvent and then suspended and granulated.
The surface treatment method for thermoplastic resin particles according to the above. 4. An additive to be mixed with said thermoplastic particles is at least one of a substance having coloring ability, a substance having charge controlling ability, a substance having fluidity controlling ability, and a substance having magnetic force. The surface treatment method for thermoplastic resin particles according to claim 1, wherein the surface treatment includes one type. 5. The thermoplastic particles have at least one of the following four substances: a substance having coloring ability, a substance having charge control ability, a substance having fluidity control ability, and a substance having magnetic force.
The surface treatment method for thermoplastic resin particles according to claim 1, 2, 3, or 4, which comprises a seed.