WO2010124616A1

WO2010124616A1 - Developer

Info

Publication number: WO2010124616A1
Application number: PCT/CN2010/072222
Authority: WO
Inventors: 汤付根; 李盛军; 谭红亮
Original assignee: 珠海思美亚碳粉有限公司
Priority date: 2009-04-30
Filing date: 2010-04-27
Publication date: 2010-11-04
Also published as: CN101876794A

Abstract

A developer for electrophotographic imaging devices comprises 100 parts by weight of toner particle, and 0.1-4 parts by weight of hydrophobic silica with a particle size of 5-20 nanometers. The toner particle comprises 100 parts by weight of binder resin with a glass transition temperature of 70-85℃, 20-200 parts by weight of magnetic colorant, 0.1-20 parts by weight of release agent, and 0.1-10 parts by weight of charge control agent. The developer does not agglomerate when stored for 48 hours at 70℃, and is capable of stable imaging at temperatures above 35℃.

Description

Developer technology

The present invention relates to a developer which is used in an electrophotographic image forming apparatus. The present invention is based on a Chinese patent application filed on Apr. 30, 2009, filed on Jan. 30, 2009, the content of which is hereby incorporated by reference. Background technique

In recent years, electrophotographic image forming apparatuses such as laser printers, copiers, facsimile machines, and MFPs have been widely used in society, especially in the field of office automation, in order to cooperate with these electrophotographic image forming apparatuses. In use, a variety of developers suitable for use in these electrophotographic image forming apparatuses have been devised.

At normal office ambient temperatures, the developer should have suitable triboelectric chargeability and charge stability, proper flowability, and good fixing properties to meet the conditions required for development, transfer, and fixing steps. Get a good, stable image output on. The general office environment temperature usually means the ambient temperature is between 10 and 35 °C. According to the national standard of the People's Republic of China (GB/T 10073-1996), the test environment temperature specified in the "Electronic copying image quality evaluation method" is 15 -25 °C.

The existing developer generally obtains a good and stable image output effect under the conditions of office environment temperature, but in the case where the ambient temperature is higher than 35 ° C, for example, the field temperature and the disaster-resistant scene with an ambient temperature of 35-65 ° C, The existing developer may cause the temperature of the surface of the developer to reach or exceed the glass transition temperature of the binder resin because the ambient temperature is too high, and friction occurs with the developing device during development, and the developer particles rub against each other. The fine external additive in the developer is easily embedded in the toner particles, so that the external additive loses its original effect, and under such high temperature conditions, the developer easily agglomerates and agglomerates in the developing device, directly affecting To the development quality, the image output is unstable, and the color density is lowered, the color density is uneven, the high bottom ash, the image is scratched, and the like, and more seriously, the image cannot be developed, so that the image text cannot be output. If a developer is required to obtain a good and stable image output at an ambient temperature higher than 35 ° C, it is necessary to provide a developer having superior high temperature resistance.

The high-temperature storage stability of the developer is also a property of interest, and the Chinese Patent Application No. CN1040101A discloses a polyester resin for a developer for an electrophotographic image forming apparatus having a glass transition temperature of 40-8 CTC. The defined glass transition temperature range is too wide when its glass transition temperature In the range of 40-7 CTC, the developer produced from the resin inevitably causes agglomeration after standing at 70 ° C for 48 hours. When the glass transition temperature is in the range of 70-8 CTC, although the problem that the produced developer is prevented from agglomerating after being left at 70 ° C for 48 hours, it is not used in combination with a certain high temperature resistant external additive. The agent cannot be printed at temperatures above 35 °C. Summary of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a developer which can perform normal imaging under a high temperature environment of 35 ° C;

Another object of the present invention is to provide a developer which can be placed at an ambient temperature of up to 70 ° C for 48 hours without causing agglomeration.

To achieve the above object, the magnetic developer provided by the present invention includes

100 parts by weight of the toner particles, the toner particles including

100 parts by weight of a binder resin having a glass transition temperature of 70-85 Torr;

20-200 parts by weight of a magnetic colorant;

0. 1-20 parts by weight of a release agent;

0. 1-10 parts by weight of a charge control agent;

0. 1-4 parts by weight of hydrophobic silica having a particle diameter of 5 to 20 nm.

The preferred embodiment is that it further comprises 0.1 to 3 parts by weight of hydrophobic silica having a particle diameter of 40 to 200 nm; 0. 05 to 2 parts by weight of the metal organic fine powder; Micro powder.

5-5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 2-2重量份; The metal organic fine powder is 0.1. The weight of the hydrophobic silica is 0. 2-2 parts by weight; 5重量份。 The 1-1. 5 parts by weight.

The non-magnetic developer provided by the present invention includes

100 parts by weight of the toner particles, the toner particles including

1-40 parts by weight of a non-magnetic colorant;

0. 1-20 parts by weight of a release agent;

0. 1-10 parts by weight of a charge control agent;

0. 1-4 parts by weight of hydrophobic silica having a particle diameter of 5-20 nm. The preferred embodiment is that it further comprises 0.1 to 3 parts by weight of hydrophobic silica having a particle diameter of 40 to 200 nm; 0. 05 to 2 parts by weight of the metal organic fine powder; Micro powder.

5-10重量份。 The charge control agent is 0. 5- 2-2重量份; The metal organic fine powder is 0. 2-2 parts by weight; the hydrophobic organic silica having a particle size of 40-200 nm is 0. 2-2 parts by weight; 1-1. 5重量份。 The 1-1. 5 parts by weight.

The glass transition temperature of the binder resin in the toner particles of the present invention is between 70 and 85 Torr, more preferably 71 to 80 °C. The glass transition temperature is lower than 70 ° C, which affects the high temperature resistance and storage stability of the developer. When the glass transition temperature is higher than 85 ° C, the fixing performance of the developer is deteriorated and the output efficiency at the time of pulverization is lowered. The binder resin also had the following characteristics, and it did not agglomerate after being left in an oven at 70 ° C for 48 hours.

Various known resins can be used as the binder resin of the present invention, such as polystyrene, poly-p-chlorostyrene, poly-α-methylstyrene, styrene-based copolymers such as styrene-chlorostyrene. Copolymer, styrene-propylene copolymer, styrene-vinyl toluene copolymer, styrene-vinyl naphthalene copolymer, styrene-acrylic acid copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate Copolymer, styrene-propyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer , styrene-propyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-methyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-ethylene Methyl ether copolymer, styrene-vinyl ethyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-ruthenium copolymer, styrene -Malay Copolymers, styrene - maleic acid ester copolymer. The above resins may be used singly or in combination of two or more. Among the above resins, a styrene-acrylate copolymer is preferred as the binder resin of the present invention.

The toner particles of the present invention further comprise a coloring agent, and when the toner is a magnetic toner, the coloring agent is selected from a black magnetic material. Specifically, it may be triiron tetroxide, antimony-iron oxide, magnetite powder, zinc iron oxide, antimony iron oxide, calcium iron oxide, antimony iron oxide, copper oxide iron, lead oxide iron, nickel iron oxide. , yttrium iron oxide, lanthanum oxyhydroxide, iron oxide iron, ferromanganese oxide, lanthanum oxyhydroxide, iron powder, cobalt powder and nickel powder. Preferred in the present invention are triiron tetroxide or antimony-ferric oxide. The average particle diameter of the magnetic material in the 0. 1-1 μ ηι, preferably 0. 1-0 5 μ _ηι;. The morphology of the particles may be spherical, cubic, an octahedral shape, and irregular shape, preferably spherical. Smaller spherical particle size facilitates more uniform dispersion of magnetic material In the toner.

When the toner of the present invention is a non-magnetic toner, the colorant is a non-magnetic colorant, and may be a black pigment and a dye, specifically carbon black, aniline black, non-magnetic ferrite, monoazo black dye, A bisazo black dye and a trisazo black dye. Carbon black is preferred in the present invention.

The toner of the present invention may contain one kind or two kinds and two or more kinds of mold release agents. The addition of the release agent helps to improve the fixing performance of the developer. The release agent may be polyethylene wax, polypropylene wax, microcrystalline wax, paraffin wax, Fischer-Tropsch wax, oxidized polyethylene wax, carnauba wax, montan acid ester wax, deacidified carnauba wax, calcium stearate, stearic acid. Zinc acid, calcium laurate, magnesium stearate, and the like. Polyethylene waxes and polypropylene waxes are preferred in the present invention.

The charge control agent plays a role in regulating and controlling the triboelectric charging of the developer in the developer. When the toner of the present invention is finally made into a negatively charged developer, the charge control agent in the toner is a negative charge control agent, which may be an organic metal complex such as a chromium-containing azo dye, monoazo. A metal complex or a chelate compound, a salicylic acid compound containing a metal such as chromium, iron or zinc, an organic metal complex containing an aromatic hydroxycarboxylic acid or an aromatic dicarboxylic acid, or the like. The present invention is preferably an organometallic complex and a metal-containing salicylic acid compound. The negative charge control agents may be used singly or in combination of two or more kinds.

When the toner of the present invention is finally made into a positively charged developer, the charge control agent in the toner is a positive charge control agent, and specific examples may include modified products such as nigrosine and its fatty acid metal salt, and organic Quaternary ammonium salts such as tributylbenzylammonium 1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate. The positive charge control agents may be used singly or in combination of two or more.

The binder resin, the colorant, the mold release agent, and the charge control agent are weighed according to the above ratio, and a toner can be produced by a conventional developer production process. The production process steps are: pre-mixing, melt-kneading, cooling, coarse pulverization, micro-grinding, grading, mixing, and sieving. The classified particles are the toner particles required in the developer of the present invention. The binder resin, the colorant, the mold release agent, and the charge control agent, which were weighed in the above ratio, were placed in a high-speed mixer manufactured by Henschel for premixing. After the components are thoroughly mixed under high-speed agitation, the premixed mixture is melt-kneaded by a screw mixer, and the temperature of the kneading is between 110 and 18 CTC, so that the coloring agent and the charge control agent are in the binder resin. It is uniformly dispersed in the binder resin in the case where the release agent is melted. The sufficiently melt-kneaded mixture can be rapidly cooled by air cooling or indirect water cooling, and the cooled mixture is coarsely pulverized by a hammer mill. The coarsely pulverized mixture was finely pulverized and classified by a jet type air flow pulverizing classifier. The jet-type airflow pulverizing and classifying machine is controlled so that the volume distribution medium diameter (MVD) value of the classified particles is between 6. 0-10. 0 μ ιη, and the volume distribution is greater than 20 μ ιη (V>20). Between 0_2%, number The distribution medium diameter (MPD) value is between 4. 0-9. Ο μ ιη, the ratio of the number distribution is greater than 5 μ ιη ( Ρ>5 ) is between 60-100%, thereby obtaining the invention described in the present invention Toner particles.

The external additive of the present invention is a small-sized hydrophobic silica having a primary average particle diameter of 5 to 20 nm produced by a surface-treated gas phase method, and a surface-treated large-particle hydrophobic colloid having an average particle diameter of 40 to 200 nm. A combination of silica, a metal organic compound fine powder, and a polymer micropowder. A small-diameter hydrophobic silica having a primary average particle diameter of 5 to 20 nm produced by a surface-treated vapor phase method is used to improve the fluidity of the toner particles and the speed and stability of triboelectric charging. Silica having a primary average particle size of 5-20 nm has very excellent fluidity. Generally, the surface of the silica particles contains a hydroxyl group, which is a hydrophilic group and is susceptible to humidity in the air. Therefore, it is necessary to apply silica to the surface of the developer to treat the surface of the silica to make the silica a hydrophobic silica. The treating agents which are usually used for surface treatment of silica for producing a positively charged developer are aminosilicon germanium, hexamethyldisilazane and cyclosilazane, etc., for use in making negatively charged development. The treating agent for the surface treatment of the silica of the agent is polydimethylsiloxane, hexamethyldisilazide, dimethyldichlorosilane, and hydrocarbyl silicon germanium. The large-diameter silica used in the present invention is produced by a colloidal method which is suitable for producing silica having an average particle diameter of 40 nm or more, and the obtained silica particles have a spherical shape. It is then treated as an external additive for the developer by surface hydrophobic treatment. The large-diameter silica adheres to the surface of the toner particles, and functions mainly to block the toner, prevent the toner particles from agglomerating and agglomerate, and improve the high temperature resistance, blocking resistance and storage stability of the developer. . Further, the spherical large-diameter silica combines with the small-diameter silica adhered to the surface of the toner particles to contribute to the improvement of the fluidity of the toner. Thus, in the case where the ambient temperature is higher than 35 °C, the excellent powder fluidity reduces the heat generated by the friction and effectively reduces the possibility of agglomeration of the developer. Due to the isolation of the large-diameter silica, the probability of the small-diameter silica being embedded in the surface of the toner during the rubbing motion is greatly reduced, so that the developer is stable in the development under high temperature conditions, achieving good performance. , stable image output effect.

The fine powder of the metal organic compound in the developer of the present invention may be zinc stearate fine powder, magnesium stearate fine powder, calcium stearate fine powder or the like, and the polymer fine powder in the developer of the present invention may be polyvinylidene fluoride. Micropowder, PTFE micropowder, melamine-based micropowder, etc. The adhesion of these fine powders to the surface of the toner also helps to prevent the developer from agglomerating and agglomerating at an ambient temperature higher than 35 ° C, improving the high temperature resistance, blocking resistance and storage stability of the developer, and It is beneficial to improve the adaptability between the developer and the organic photosensitive drum (0PC), making the output of the image more stable.

According to the above ratio, small particle size silica, large particle size silica, metal organic powder The high molecular weight polymer powder was weighed and placed in a high-speed mixer manufactured by Henschel for high-speed and sufficient mixing so that the external additives were uniformly adhered to the surface of the toner. The mixed mixture is then sieved on an ultrasonic vibrating screen to remove coarse particles produced during the post-mixing process, and finally the developer described in the present invention is obtained. detailed description

The scheme and the preparation method of the present invention have been described above, and an embodiment according to the present invention is given below. The first embodiment of the invention:

Styrene-acrylate copolymer resin (Tg=73 °C) 100 weight: t part

Triiron tetroxide 80 weight: t share

Polypropylene wax 2 weight: t parts

Chromium-containing azo dye 1 weight: [: serving

The above four materials were produced into toner particles in accordance with the aforementioned conventional developer production process. The particle characteristics of the toner are:

MVD 7. 8 μ m

V>20 0%

MPD 6. 6 μ m

P>5 85. 8%

Then, weigh the following materials:

Toner particles loo weight [: serving

Silica (primary average particle size 14nm) 1 weight: I: part

Colloidal silica (average particle size lOOnm) 0. 3 parts by weight

1% by weight of stearic acid micropowder

Polyvinylidene fluoride fine powder 0.2 parts by weight

The developer is produced in accordance with the aforementioned conventional developer production process.

A second embodiment of the invention:

Toner particles as in the first embodiment 100 parts by weight

Silica (primary average particle size 14 nm) 1. 5 parts by weight

To further illustrate the advantages of the present invention, a comparison of the test results of the above two embodiments with an existing developer is given below. 1. Evaluation of anti-caking properties

The developer prepared in the first and second embodiments of the present invention and a conventional developer are placed in an oven at a constant temperature of 70 ° C for 48 hours, and then taken out to pick up the developer with a small spoon, and visually inspected. It is judged whether the developer is agglomerated. The results are shown in Table 1.

2. Evaluation of the effect of printout image

The first and second embodiments of the present invention and an existing developer are loaded into a toner cartridge for the HP LaserJet 1010 model, and then the toner cartridge is loaded into the HP LaserJet 1010 machine, and the machine is placed together with the paper. Continuously placed for 24 hours in an environmental test chamber with low temperature and low humidity (10 ° C, relative humidity 30%), normal temperature and humidity (23 ° C, relative humidity 60%) and high temperature and high humidity (30 ° C, relative humidity 90%) Then print it. The printed manuscript is obtained by measuring the density of the solid image on the printing paper using a color densitometer (D19C, GretagMacbeth Co., Ltd.) to obtain a color density value (SAD) by using a gamma meter (Model 577, PH0T0V0LT Co., Ltd.) The bottom gray value (BG) is obtained by measuring the difference between the value of the blank area on the printing paper and the value of the area covered by the additional paper (the area not subjected to transfer). The effect of the printout image is evaluated by the color density value and the bottom gray value.

The first and second embodiments of the present invention and an existing developer are loaded into a toner cartridge for the HP LaserJet 1010 model, and then the toner cartridge is loaded into the HP LaserJet 1010 machine, and the machine is placed together with the paper. The temperature was constant at 65 ° C in an oven and printing was continued for 48 hours. The printed manuscript is obtained by measuring the density of the solid image on the printing paper using a color densitometer (D19C, GretagMacbeth Co., Ltd.) to obtain a color density value (SAD) by using a gamma meter (Model 577, PH0T0V0LT Co., Ltd. ) The bottom gray value (BG) is obtained by measuring the difference between the value of the blank area on the printing paper and the value of the area covered by the additional paper (the area not subjected to transfer). The effect of the printout image is evaluated by the color density value and the bottom gray value.

The first and second embodiments of the present invention and an existing developer are loaded into a toner cartridge for the HP LaserJet 1010 model, and then the toner cartridge is loaded into the HP LaserJet 1010 machine, and the machine is placed together with the paper. Printing was carried out in an oven at a constant temperature of 70 ° C for 3 hours. The printed manuscript is obtained by measuring the density of the solid image on the printing paper using a color densitometer (D19C, GretagMacbeth Co., Ltd.) to obtain a color density value (SAD) by using a gamma meter (Model 577, PH0T0V0LT Co., Ltd. ) The bottom gray value (BG) is obtained by measuring the difference between the value of the blank area on the printing paper and the value of the area covered by the additional paper (the area not subjected to transfer). The effect of the printout image is evaluated by the color density value and the bottom gray value. The results are shown in Table 2.

Table 1 Acamination of each developer after standing at 70 ° C for 48 hours Developer agglomeration

The first embodiment has no agglomeration.

The second embodiment has no agglomeration.

The existing developer has agglomerated and the block is relatively hard.

Table 2 Printed output image effects of each developer under different environments

As can be seen from the test results, the first and second embodiments according to the present invention have excellent high temperature resistance, blocking resistance and storage stability. It is kept at a temperature of 70 ° C for 48 hours without agglomeration, and has excellent anti-knot performance, while the existing developer is agglomerated; at an ambient temperature higher than 35 ° C, Excellent and stable image output effects can be obtained, and with the present invention, the first embodiment has better image quality than the second embodiment.

The above two embodiments of the present invention are only used for the description of the present invention, and are not intended to limit the present invention. According to the concept of the present invention and the above description, there are many simple component content changes and component selections. Many embodiments are within the scope of the claims of the present invention. Industrial applicability

The developer provided by the invention has better high temperature resistance than the general developer, and at an ambient temperature higher than 35 ° C, an excellent and stable image can be obtained, so that the developer can not only It is used in a general office environment and can be used in environments where the ambient temperature is higher than normal. And it is kept at an ambient temperature of 70 ° C for 48 hours without causing agglomeration, and has excellent anti-knot property, so that it has more excellent storage stability than a general developer.

Claims

Claim

1. Developer, including:

100 parts by weight of the toner particles, the toner particles including

100 parts by weight of a binder resin having a glass transition temperature of 70 to 85 Å; 20 to 200 parts by weight of a magnetic colorant;

0. 1-20 parts by weight of a release agent;

0. 1-10 parts by weight of a charge control agent;

2. The developer according to claim 1, further comprising:

0 to 1-3 parts by weight of hydrophobic silica having a particle diameter of 40 to 200 nm;

0. 05-2 parts by weight of metal organic fine powder;

0. 05-2 parts by weight of a high molecular polymer fine powder.

3. The developer according to claim 2, wherein: the binder resin has a glass transition temperature of 71-8 CTC;

The magnetic colorant is 30-120 parts by weight;

5-10重量份; The release agent is 0. 5-10 parts by weight;

5-5重量份; The charge control agent is 0. 5-5 parts by weight;

2-2重量份; The metal organic matter; the hydrophobic silica having a particle size of 40-200 nm is 0. 2-2 parts by weight;重量重量为; 1-1. 5重量份;

5重量份。 The high molecular weight polymer is 0. 1-1. 5 parts by weight.

4. Developer, including:

100 parts by weight of the toner particles, the toner particles including

1-40 parts by weight of a non-magnetic colorant;

0. 1-20 parts by weight of a release agent;

0. 1-10 parts by weight of a charge control agent;

5. The developer according to claim 4, wherein:

Also includes

0. 05-2 parts by weight of metal organic fine powder;

0. 05-2 parts by weight of a high molecular polymer fine powder.

The developer according to claim 5, wherein the binder resin has a glass transition temperature of 71-8 CTC;

The non-magnetic colorant is 30-120 parts by weight;

5-10重量份; The release agent is 0. 5-10 parts by weight;

5-5重量份; The charge control agent is 0. 5-5 parts by weight;

5重量份。 The high molecular weight polymer is 0. 1-1. 5 parts by weight.