KR20150016826A - Polymerized toner and process for preparing thereof - Google Patents

Abstract

The present invention relates to a polymerized toner and a method for producing the same, and more particularly, to a polymerized toner capable of obtaining a high-gloss printed matter upon printing and a method for producing the same. According to the polymerized toner of the present invention, it is possible to provide a toner having high gloss and good transfer efficiency.

Description

POLYMERIZED TONER AND PROCESS FOR PREPARING THEREOF [0002]

The present invention relates to a polymerized toner and a method for producing the same, and more particularly, to a polymerized toner which is obtained by adding an additive having a refractive index higher than that of the binder resin of the toner, ≪ / RTI >

Toner is used for electrophotographic development, electrostatic printer, copying machine, and the like, and refers to a paint capable of forming a desired pattern by being transferred and fixed on an object to be transferred. Recently, with the generalization of document making using a computer, etc., demand for an image forming apparatus such as a printer is rapidly increasing, and accordingly, the amount of toner used is also increasing.

Generally, as a method for producing toner, there are a manufacturing method using pulverization and a manufacturing method using polymerization.

In the manufacturing method using pulverization, a resin and a pigment are put together through a melt-mixing process, and the toner particles are produced by melting-mixing or extruding, pulverizing and classifying. However, when the toner particles are produced by this process, if the content of the wax exceeds 5% by weight, the wax domain can be largely generated, and the wax is cleaved around the wax in the pulverization process, The image has a serious adverse effect. Therefore, in order to improve the fixability of the toner and to improve the gloss of the printed material, the content of the wax is limited to about 2 wt% to 5 wt%.

The production method using polymerization has no physical pulverization process and can increase the content of wax to 20% by weight and provide a toner having a high gloss and off-set windows as compared with the toner prepared by the pulverization method . However, in the polymerized toner, when the content of the wax is more than a certain ratio, the wax domain becomes larger inside the toner particles, and is located on the toner particle surface side. As a result, the charge amount of the toner particles is lowered, and the transfer efficiency and the long-term image characteristics during printing are lowered. Therefore, the use amount thereof is limited and there is a limitation in obtaining a higher glossiness than the conventional ones.

Therefore, in the method for producing a toner by a polymerization method, it is necessary to study additives other than conventional waxes in order to produce a toner having a very uniform chargeability and high gloss.

The present inventors have conducted intensive studies to solve the problems of the prior art as described above. As a result, they have found that when a substance having a refractive index higher than that of the binder resin is added, the additives are located on the surface of the toner, And the present invention has been completed.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a polymerized toner which exhibits visually high gloss after printing by introducing an additive having a refractive index higher than that of the binder resin during polymerization, and a process for producing the polymerized toner.

The present invention includes a binder resin, a pigment dispersed in the binder resin, a pigment stabilizer, a charge control agent, a wax, a dispersant, and a first additive, wherein the first additive is present in an amount of about 0.5 parts by weight To about 15 parts by weight, and the refractive index of the first additive is greater than the refractive index of the binder resin.

The present invention also relates to a method for producing an aqueous dispersion comprising the steps of: forming an aqueous dispersion containing a dispersing agent; Forming a monomer mixture comprising a monomer for a binder resin, a pigment, a pigment stabilizer, a charge control agent, a wax, and a first additive; And adding the monomer mixture to the aqueous dispersion and forming toner particles comprising a binder resin through suspension polymerization, wherein the first additive is present in an amount of from about 0.5 parts by weight to about 100 parts by weight per 100 parts by weight of the binder resin And the refractive index of the first additive is greater than the refractive index of the binder resin.

The polymerized toner according to the present invention can realize a uniform image with high image density and gloss. In particular, according to one embodiment of the present invention, it is possible to manufacture a toner having a very high physical property such as glossiness of not less than 37 on a printing paper.

Accordingly, the polymerized toner of the present invention can be applied to fields such as development of electrophotographic images requiring high image realization, and it is possible to obtain printing products of excellent quality with excellent resolution and color implementation.

Hereinafter, a polymerization toner according to a specific embodiment of the present invention and a method for producing the same will be described in detail. It will be apparent to those skilled in the art that various modifications may be made to the embodiments without departing from the spirit and scope of the invention as defined by the appended claims. .

In the present invention, the terms first, second, etc. are used to describe various components, and the terms are used only for the purpose of distinguishing one component from another.

Moreover, the terminology used herein is for the purpose of describing exemplary embodiments only and is not intended to be limiting of the present invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms "comprising," "comprising," or "having ", and the like are intended to specify the presence of stated features, But do not preclude the presence or addition of one or more other features, integers, steps, components, or combinations thereof.

Hereinafter, the present invention will be described in detail.

According to an aspect of the present invention, there is provided a recording material comprising a binder resin and a pigment, a pigment stabilizer, a charge control agent, a wax, a dispersant, and a first additive dispersed in the binder resin, wherein the first additive has a refractive index Thereby providing a polymerized toner having a large value.

The first additive contained in the toner particles is normally located in the toner particles, and when the toner particles are melted in the transfer step, the first additives are exposed to the surface to increase the refractive index, thereby enhancing the glossiness.

When the first additive is included in an amount of about 0.5 to about 15 parts by weight based on about 100 parts by weight of the binder resin, the chargeability of the toner particles is affected, Can be advantageous because it exhibits an improvement effect. More preferably, the first additive may be included in an amount of about 1 part by weight to about 10 parts by weight based on about 100 parts by weight of the binder resin.

According to an embodiment of the present invention, the binder resin may be at least one selected from the group consisting of a styrene monomer, an acrylate monomer, a methacrylate monomer, a diene monomer, an acidic olefin monomer, and a basic olefin monomer . ≪ / RTI >

In addition, in the process of melting and transferring the toner during printing, the first additive must be able to be positioned on the toner surface side to effectively increase the gloss, so that when an acrylate binder resin having higher hydrophilicity than styrene is used, It is more effective in increasing the glossiness than when a naphthalene-based binder resin is used. However, when the first additive is added, the materials used as the binder resin remain unchanged in that they have a higher gloss than the conventional toner.

The first additive may be dissolved in a binder resin monomer in the form of a polymer resin, or may participate in a polymerization reaction in the form of a monomer upon polymerization of the toner to form a chain. The first additive may have a refractive index larger than that of the binder resin Can be used without limitation. For example, the binder resin may comprise a polymer of a styrenic monomer and an acrylate monomer, and the first additive may have a refractive index greater than 1.59.

According to an embodiment of the present invention, the first additive may be at least one selected from the group consisting of poly (naphthyl methacrylate), polyvinylphenyl sulfide, polyvinyl naphthalene, naphthalene-formaldehyde resin (Naphthalene-formaldehyde resin), and N-vinyl phthalimide (N-vinyl phthalimide).

According to one embodiment of the present invention, the wax may be at least one selected from the group consisting of petroleum refining wax, natural wax, and synthetic wax. The petroleum refining wax may be at least one petroleum refining wax selected from the group consisting of paraffin wax, microcrystalline wax and ceresin wax. The natural wax may be a carnuba wax. The synthetic wax may be polyethylene and polypropylene And at least one selected from the group consisting of

The amount of the wax may be about 0.01 to about 50 parts by weight, preferably about 3 to about 30 parts by weight, and more preferably about 6 to about 20 parts by weight based on about 100 parts by weight of the binder resin. When the wax is contained in an amount of less than about 3 parts by weight, the glossiness may decrease. When the wax is more than about 30 parts by weight, the transfer efficiency and the long-term image characteristics may be deteriorated.

According to an embodiment of the present invention, the pigment may be at least one selected from the group consisting of a metal powder type pigment, a metal compounding type pigment, a carbon type pigment, a sulfide type pigment, a chromium salt type pigment, a ferrocyanide type pigment, an azo type pigment, At least one selected from the group consisting of dye type pigments, modand dye type pigments, phthalocyanine, quinacridone type pigments, and dioxane type pigments.

The content of the pigment may be about 1 to about 30 parts by weight, preferably about 3 to about 15 parts by weight, and more preferably about 5 to about 10 parts by weight based on about 100 parts by weight of the binder resin.

According to one embodiment of the present invention, the charge control agent may be a cationic charge control agent or an anionic charge control agent. The cationic charge control agent may include at least one selected from the group consisting of nigrosine type electron acceptor dyes, higher aliphatic metal salts, alkoxy amines, chelates, quaternary ammonium salts, alkyl amides, fluorine treatment activators and metal salts of naphthalic acid Wherein the anionic charge control agent may comprise at least one member selected from the group consisting of an electron acceptor organic complex, a chlorinated paraffin, a chlorinated polyester, a polyester containing an acid, and a styrene-acrylic polymer containing a sulfonic acid group Or may include at least one selected from the group consisting of azo metal complexes of chromium, salicylic acid metal complexes and chromium chromium organic dyes.

The content of the charge control agent may be about 0.01 to about 30 parts by weight, preferably about 0.1 to about 7 parts by weight, and more preferably about 0.5 to about 5 parts by weight based on about 100 parts by weight of the binder resin.

According to one embodiment of the present invention, the dispersant may include at least one selected from the group consisting of a water-soluble inorganic dispersant, a water-soluble organic polymer dispersant, and an anionic surfactant.

The water-soluble inorganic dispersant may include at least one member selected from the group consisting of a calcium phosphate salt, a magnesium salt, a hydrophilic silica, a hydrophobic silica, and a colloidal silica.

The water-soluble organic polymer dispersant may be a nonionic organic polymer dispersant or an ionic organic polymer dispersant.

The nonionic organic polymeric dispersant may be selected from the group consisting of polyoxyethylene alkyl ether, polyoxyalkylene alkylphenol ether, sorbitan esters of fatty acids, polyoxyalkylene esters Polyoxyethylene fatty acid esters, polyoxyalkylene fatty acid esters, glycerin esters of fatty acids, polyvinyl alcohol, alkyl cellulose, and polyvinyl pyrrolidone. Wherein the ionic organic polymeric dispersant is selected from the group consisting of polyacrylamide, polyvinylamine, polyvinylamine N-oxide, polyvinyl ammonium salt, Polydialkyldiallyl ammonium salt, Polyacrylic acid, Polystyrene su a polyacrylate salt, a polystyrene sulfonate salt, a polyaminoalkyl acrylate salt, and the like may be included in the composition of the present invention.

The content of the dispersing agent may be about 0.01 to about 15 parts by weight based on about 100 parts by weight of the binder resin.

According to one embodiment of the present invention, the pigment stabilizer may be a styrene-butadiene-styrene (SBS) copolymer having a weight average molecular weight of about 2,000 to about 200,000, May be from about 10: 90 to about 90: 10 by weight. If the content of styrene is more than about 90 wt%, the length of the butadiene block is shortened and compatibility with the binder resin is increased, so that it can not sufficiently act as a stabilizer. If the content is less than about 10 wt% The effect of the pigment to pigment can not be sufficiently controlled due to the length of the block. If the molecular weight is less than about 2,000, the pigment can not function as a pigment stabilizer because of its high compatibility with the binder resin. If the molecular weight is about 200,000 or more, the viscosity of the monomer mixture becomes too high, which deteriorates dispersion stability and polymerization stability. A disadvantage of spreading appears.

The content of the pigment stabilizer may be about 1 to about 30 parts by weight, preferably about 1.5 to about 15 parts by weight, and more preferably about 2 to about 7 parts by weight based on about 100 parts by weight of the binder resin.

On the other hand, the polymerized toner may further include a second additive such as a crosslinking agent, a molecular weight modifier, a lubricant (e.g., oleic acid, stearic acid, etc.), a coupling agent,

According to an embodiment of the present invention, the content of the second additive may be about 1 to about 15 parts by weight, and preferably about 1 to about 5 parts by weight based on about 100 parts by weight of the binder resin.

According to an embodiment of the present invention, the crosslinking agent may be selected from the group consisting of divinyl benzene, ethylene dimethacrylate, ethyleneglycol dimethacrylate, diethyleneglycol diacrylate ), 1,6-hexamethylene diacrylate, allyl methacrylate, 1,1,1-trimethylolpropane triacrylate (1,1,1-trimethylolpropane triacrylate) triacrylate, triallylamine, tetraallyloxyethane, and the like.

The amount of the crosslinking agent may be about 0.1 to about 30 parts by weight, preferably about 0.2 to about 15 parts by weight, and more preferably about 0.2 to about 7 parts by weight based on about 100 parts by weight of the binder resin.

According to one embodiment of the present invention, the molecular weight regulator may be t-dodecyl mercaptan, n-dodecyl mercaptan, n-octyl mercaptan, ), Carbon tetrachloride, and the like.

The content of the molecular weight modifier may be about 0.1 to about 10 parts by weight, preferably about 0.25 to about 5 parts by weight, and more preferably about 0.3 to about 4 parts by weight based on about 100 parts by weight of the binder resin.

These actives and coupling agents are known to be applicable to the production of polymerized toners can be used without limitation.

According to one embodiment of the present invention, the average particle diameter of the toner particles in the polymerized toner of the present invention is about 4 to about 10 mu m, preferably about 5 to about 8 mu m, and more preferably about 6 to about 7 mu m . The average particle diameter of the toner particles may be about 4 占 퐉 or more in terms of image density and scattering prevention, and the average particle diameter of the toner particles may be about 10 占 퐉 or less in terms of cost reduction.

On the other hand, according to an embodiment of the present invention, a method for producing the polymerized toner may be provided.

In particular, the method for producing the polymerized toner includes the steps of: forming an aqueous dispersion containing a dispersant; Forming a monomer mixture comprising a monomer for a binder resin, a pigment, a pigment stabilizer, a charge control agent, a wax, and a first additive; And adding the monomer mixture to the aqueous dispersion and forming toner particles containing the binder resin through suspension polymerization, wherein the refractive index of the first additive is larger than the refractive index of the binder resin.

According to one embodiment of the present invention, the aqueous dispersion in which the monomer mixture is dispersed may be formed by mixing a dispersant in water. The dispersant prevents agglomeration between the particles of the binder resin or the pigment, which are present in the form of droplets in the aqueous medium, and enables such particles to be uniformly dispersed. In addition, the dispersant uniformly adsorbs on the surface of the droplet to stabilize the droplet particle. Such a dispersing agent can be solubilized in the aqueous medium through the acid or alkali treatment or hot water washing after completion of the polymerization reaction, and can be separated from the toner particles.

According to one embodiment of the present invention, the dispersant may be at least one selected from the group consisting of a water-soluble inorganic dispersant, a water-soluble organic dispersant, and an anionic surfactant. Such a dispersing agent may be used in an amount of about 0.1 to about 10 parts by weight based on the total weight of the aqueous dispersion, Preferably from about 0.2 to about 5 parts by weight, and more preferably from about 0.3 to about 3 parts by weight. Specific examples of the water-soluble inorganic dispersant include calcium phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate, hydroxyapatite, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, magnesium hydroxide, , Calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica, alumina or mixtures thereof. Specific examples of the water-soluble organic dispersant include polyvinyl alcohol, gelatin, methyl cellulose, methylhydroxypropyl cellulose, ethyl cellulose, carboxymethyl cellulose, cellulose and its sodium salt, polyacrylic acid and salts thereof, starch, or a mixture thereof.

More preferred examples of the dispersant include silica, calcium phosphate, polyvinyl alcohol, and the like. Among them, calcium phosphate can be obtained in the form of crystals in an aqueous solution by mixing sodium phosphate aqueous solution and calcium chloride aqueous solution, and the aqueous dispersion may be a form in which calcium phosphate crystals are uniformly dispersed in water.

According to one embodiment of the present invention, the step of forming the toner particles through the suspension polymerization comprises reacting at about 50 ° C to about 70 ° C for about 8 hours to about 12 hours, Followed by a reaction for about 30 minutes to about 4 hours after elevated temperature.

More preferably, the suspension polymerization is carried out by suspending polymerization at a temperature of about 50 캜 to about 60 캜 for about 8 hours to about 12 hours, and a temperature of about 80 캜 to about 110 캜 for about 30 minutes to about 4 hours Reaction can proceed. By using such a suspension polymerization method, a toner having high gloss can be obtained.

According to an embodiment of the present invention, the monomer mixture may further comprise at least one second additive selected from the group consisting of a crosslinking agent, a molecular weight modifier, a lubricant, a coupling agent, and a plasticizer. The characteristics and content of the second additive are as described above.

According to one embodiment of the present invention, the step of forming the toner particles through the suspension polymerization comprises the steps of: adding the monomer mixture to the aqueous dispersion; Applying a shear force to the aqueous dispersion and the monomer mixture to homogenize the monomer mixture in the form of a droplet in an aqueous dispersion; And suspending and polymerizing the homogenized monomer mixture.

According to one embodiment of the present invention, the monomer mixture and the aqueous dispersion may be homogenized using a homogenizer. Spherical toner particles of an appropriate size can be formed by uniformly dispersing the monomer mixture in the form of droplets in the aqueous dispersion and proceeding the polymerization reaction. In order to disperse the liquid droplets, a homogenizer may be used to homogenize the monomer mixture and the aqueous dispersion by applying a shearing force. Specifically, the monomer mixture mixed with the aqueous dispersion may be homogenized using a homogenizer at about 5,000 rpm Homogenizing at a rate of about 20,000 rpm, preferably about 8,000 rpm to about 17,000 rpm, to disperse the monomer mixture in the form of microdroplets in the aqueous dispersion.

In another embodiment of the present invention, And drying the toner particles.

The step of removing the dispersant may include a step of adjusting the pH to a level suitable for dissolving the dispersant. Adding a water-soluble inorganic acid such as hydrochloric acid or nitric acid to the dispersion in which the toner particles are formed to adjust the pH to about 2 or less, preferably about 1.5 or less, thereby dissolving the dispersant in an aqueous liquid phase to remove it from the toner particles can do. In the step of removing the dispersant, the pH is appropriately adjusted, and the solution is stirred for about 5 hours or more to allow the dispersant to sufficiently dissolve. Thereafter, the toner slurry containing less than about 50 parts by weight of water relative to about 100 parts by weight of the toner Can be obtained.

In addition, the step of removing the dispersant may include a step of homogenizing the solution by applying a shear force with a homogenizer, and a separation step using a centrifugal separator. After the above-described dispersing agent removing step, the dispersing agent can be removed more efficiently by repeating the water removal using the filter device and the addition of the excessive distilled water several times.

According to an embodiment of the present invention, the step of drying the toner particles may include a step of putting a toner cake in which a dispersant has been removed into a vacuum oven and vacuum drying at room temperature. However, the present invention is not limited thereto, and a drying method known to be commonly used in the production of a polymerized toner can be used without any limitation.

In another embodiment of the present invention, the method may further include coating the outside of the toner particles. In this coating step, an inorganic powder including an external additive such as silica, titanium dioxide, or a mixture thereof may be coated on the surface of the toner particles. In the coating step of the external additive, Adding an external additive to the particles, and then stirring at a high speed. The silica can be used without limitation as long as it is known to be usable for polymerized toner.

On the other hand, the polymerized toner of the present invention is capable of realizing high image density and gloss, is uniform, and can have a very excellent physical property, particularly a glossiness of about 37 or more in a printing paper.

The matters other than the contents described above can be added or subtracted as required in the present invention, and therefore they are not particularly limited in the present invention.

Best Mode for Carrying Out the Invention Hereinafter, the function and effect of the present invention will be described in more detail through specific examples of the present invention. It is to be understood, however, that these embodiments are merely illustrative of the invention and are not intended to limit the scope of the invention.

[ Example  One]

Production of Polymerized Toner

686 g of 0.1 M sodium phosphate aqueous solution and 100 g of 1 M calcium chloride were mixed with 500 g of water and stirred at a reaction temperature of 70 캜 for 20 minutes to prepare an aqueous dispersion in which calcium phosphate crystals were precipitated. The content of calcium phosphate in the aqueous dispersion was 3 parts by weight based on 100 parts by weight of the following monomer mixture.

160 g of styrene, 36 g of n-butylacrylate, 4 g of vinyl naphthalene as a first additive, 4 g of allyl methacrylate as a cross-linking agent, 0.4 g of n-Dodecyl mercaptan, 3 g of a styrene-butadiene-styrene (SBS) block copolymer having a molecular weight of 10,000 as a pigment stabilizer, 3 g of a styrene-butadiene-styrene block copolymer having a weight average molecular weight of 16,500 - 4 g of acrylic polymer charge control agent (Styrene / 2EHA / anionic functional monomer copolymer, FCA 1001 NS, Fujikura Kasei) were mixed and thoroughly dissolved. 10 g of carbon black was added thereto and stirred in a bead mill at 2,000 rpm for 1 hour. Respectively.

20 g of ester wax was added to the mixture from which the beads had been removed and stirred to make the wax completely dissolved. 4 g of an azonitrile initiator (V65, Waco Chemical) was added and stirred for 5 minutes to obtain a monomer mixture . At this time, the weight of the monomer mixture was 245.4 g.

The monomer mixture was added to the aqueous dispersion and subjected to shear force at a speed of 13,000 rpm using a homogenizer to disperse the monomer mixture in the form of fine droplets in the aqueous dispersion and homogenize. The monomer mixture dispersed in the aqueous dispersion in the form of fine droplets through the homogenization was reacted at 60 ° C for 10 hours with stirring at 200 rpm with a paddle type agitator, heated to 90 ° C and further reacted for 3 hours to obtain a polymerized toner .

Cleaning and drying toner particles

Hydrochloric acid was added to the slurry containing the polymerized toner to adjust the pH to 2 or less, and the calcium phosphate was dissolved. After centrifugation (Beckman J2-21M, Rotor JA-14), the mixture was centrifuged and centrifuged to remove the supernatant. The supernatant was filtered through a filter to remove water, diluted by adding twice distilled water to the total weight, homogenized with a homogenizer, And centrifuged at 3,000 rpm for 15 minutes. This dilution, homogenization and centrifugation process was repeated three times to remove calcium phosphate and other impurities on the toner surface.

Finally, after the water was removed through filtration, the toner cake was put in a vacuum oven and vacuum-dried at room temperature for 48 hours to prepare a polymerized toner core. The volume average particle diameter of the polymerized toner core thus prepared was 7 mu m and the ratio (standard deviation) of the volume average particle diameter to the number average particle diameter was 1.26. At this time, the volume average particle diameter of the core was measured using a Coulter counter (Multisizer 3, Beckman coulter).

External additive  coating

2 parts by weight of silica was added to 100 parts by weight of the polymerized toner core using a Henschel mixer, and the mixture was stirred at a speed of 5,000 rpm for 7 minutes at a high speed to coat the surface of the polymerized toner core with an external additive.

[ Example  2]

Except that 4 g of poly beta naphthyl methacrylate as a first additive was added to styrene / butylacrylate monomer, which was sufficiently stirred for about 1 hour and then milled. 1, a polymerized toner was prepared.

[ Example  3]

A polymerized toner was prepared in the same manner as in Example 2 except that 4 g of polyvinylphenyl sulfide was used as the first additive.

[ Example  4]

A polymerized toner was prepared in the same manner as in Example 2 except that 4 g of naphthalene-formaldehyde resin was used as the first additive.

[ Comparative Example  One]

A polymerized toner was prepared in the same manner as in Example 1 except that the first additive was not present.

[ Comparative Example  2]

A polymerized toner was prepared in the same manner as in Example 1, except that 4 g of methyl methacrylate was used.

[ Comparative Example  3]

A polymerized toner was prepared in the same manner as in Example 1 except that 4 g of ethyl acrylate was used.

[ Comparative Example  4]

A polymerized toner was prepared in the same manner as in Example 1, except that 0.5 g of vinyl naphthalene was used as the first additive.

[ Comparative Example  5]

A polymerized toner was prepared in the same manner as in Example 1, except that 30 g of vinyl naphthalene was used as the first additive.

[ Experimental Example ]

The polymerized toners prepared in Examples 1 to 4 and Comparative Examples 1 to 5 were evaluated for physical properties as follows.

[ Experimental Example  One]

Evaluation of Toner Transfer Efficiency

After the polymerized toner prepared according to Examples 1 to 4 and Comparative Examples 1 to 5 was filled in the supply portion of the laser printer (CP2025, Hewlett-Packard) cartridge, the weight of the entire supply portion was measured. A rectangle with a width of 19 cm and a length of 1.5 cm was printed on A4 size paper, and then the weight of the feeding portion was measured again, and the amount of toner consumption was calculated as shown in the following Equation 1.

[Equation 1]

Consumption (g) = 1,000 sheets Weight of feed before printing - 1,000 sheets Feed after printing

Also, the weight of the drum part separable from the feeding part was measured before printing, and after printing, the amount of toner that could not be transferred onto paper was calculated as shown in the following equation (2).

[Equation 2]

Amount of toner to be wasted (g) = 1,000 sheets Weight of drum after printing - 1,000 sheets Weight of drum before printing

After the amount of consumed and wasted toner was measured as described above, the transfer efficiency was calculated by the following equation 3. < EMI ID = 3.0 >

[Equation 3]

Transfer efficiency (%) = {(amount of consumption - amount of waste toner) / amount of consumption} × 100

[ Experimental Example  2]

Gloss measurement

After printing on A4-sized paper with a laser printer (CP1215, Hewlett-Packard), measure the gloss of four corners and one center of the print paper using the gloss meter (RD918, Mcbath) The average value was taken.

The results of Experimental Examples 1 and 2 are summarized in Table 1 below.

division additive Refractive index The first additive
Content (g) Glossiness Transfer efficiency
(%) Example 1 Vinyl naphthalene 1.66 4 42 85 Example 2 Poly β naphtayl methacrylate 1.61 4 40 83 Example 3 Polyvinylphenyl sulfide 1.65 4 42 71 Example 4 Naphthalene-formaldehyde resin 1.68 4 43 81 Comparative Example 1 No additive (ST / BA resin) 1.59 0 36 81 Comparative Example 2 Methyl methacrylate 1.49 4 34 74 Comparative Example 3 Ethyl acrylate 1.47 4 33 82 Comparative Example 4 Vinyl naphthalene 1.66 0.5 37 85 Comparative Example 5 Vinyl naphthalene 1.66 30 43 62

As shown in Table 1, when the additive having the refractive index larger than the refractive index of the binder resin according to the present invention is included, the glossiness is remarkably superior to that of the toner particles not containing the additive.

Further, as in the results of Comparative Examples 4 and 5, the gloss improving effect and the transfer efficiency may be somewhat changed depending on the type and content of the additive used. This is because the characteristics and content of the additive depend on the charge structure As well as in the case of the US. However, it can be confirmed that in all cases where the additive having the refractive index larger than the refractive index of the binder resin is included, the gloss can be remarkably improved as compared with the conventional toner.

On the other hand, in Comparative Examples 2 and 3 using a material having a refractive index smaller than that of the styrene-based resin as the basic binder resin, it can be confirmed that the gloss decreases.

Claims (16)

Binder resin; And
A pigment stabilizer, a charge control agent, a wax, a dispersant, and a first additive dispersed in the binder resin,
Wherein the refractive index of the first additive is greater than the refractive index of the binder resin.
The method according to claim 1,
Wherein the binder resin is a polymerized toner comprising a polymer of at least one monomer selected from the group consisting of a styrenic monomer, an acrylate monomer, a methacrylate monomer, a diene monomer, an acidic olefin monomer, and a basic olefin monomer .
3. The method according to claim 1 or 2,
The first additive is selected from the group consisting of poly beta naphthyl methacrylate, polyvinylphenyl sulfide, polyvinyl naphthalene, naphthalene-formaldehyde resin, and N (N-vinyl phthalimide). ≪ Desc / Clms Page number 13 >
The method according to claim 1,
Wherein the binder resin comprises a polymer of a styrene-based monomer and an acrylate-based monomer, and the first additive has a refractive index of greater than 1.59.
The method according to claim 1,
Wherein the first additive is contained in an amount of 0.5 to 15 parts by weight based on 100 parts by weight of the binder resin.
The method according to claim 1,
Wherein the wax comprises at least one member selected from the group consisting of petroleum refining wax, natural wax, and synthetic wax.
The method according to claim 1,
The pigment may be at least one selected from the group consisting of a metal powder type pigment, a metal compounding type pigment, a carbon type pigment, a sulfide type pigment, a chromium salt type pigment, a ferrocyanide type pigment, an azo type pigment, an acid type dye type pigment, a basic dye type pigment, , Phthalocyanine, quinacridone-type pigment, and dioxane-type pigment.
The method according to claim 1,
Wherein the charge control agent is a cationic charge control agent, or an anionic charge control agent.
The method according to claim 1,
Wherein the dispersing agent comprises at least one selected from the group consisting of an inorganic dispersant, a water-soluble organic polymer dispersant, and an anionic surfactant.
The method according to claim 1,
And at least one second additive selected from the group consisting of a crosslinking agent, a molecular weight modifier, a lubricant, a coupling agent, and a plasticizer.
Forming an aqueous dispersion comprising a dispersing agent;
Forming a monomer mixture comprising a monomer for a binder resin, a pigment, a pigment stabilizer, a charge control agent, a wax, and a first additive; And
Adding the monomer mixture to the aqueous dispersion and forming toner particles containing the binder resin through suspension polymerization,
Wherein the refractive index of the first additive is greater than the refractive index of the binder resin.
12. The method of claim 11,
Wherein the first additive is contained in an amount of 0.5 to 15 parts by weight based on 100 parts by weight of the binder resin.
12. The method of claim 11,
The step of forming the toner particles containing the binder resin through the suspension polymerization may include a step of reacting at 50 캜 to 70 캜 for 8 hours to 12 hours and a step of raising the temperature to 80 캜 to 100 캜 for 30 minutes to 4 hours And at least one of the following steps.
12. The method of claim 11,
Wherein the monomer mixture further comprises at least one second additive selected from the group consisting of a crosslinking agent, a molecular weight modifier, a lubricant, a coupling agent, and a plasticizer.
12. The method of claim 11,
Further comprising the step of removing the dispersing agent and the step of drying the toner particles after the step of forming the toner particles.
12. The method of claim 11,
The step of forming the toner particles including the binder resin through the suspension polymerization includes:
Adding the monomer mixture to the aqueous dispersion;
Applying a shear force to the mixture of the monomer mixture and the aqueous dispersion to homogenize the monomer mixture in the aqueous dispersion in the form of droplets; And
And forming toner particles containing a binder resin through suspension polymerization of the homogenized monomer mixture.