WO2018188554A1

WO2018188554A1 - Preparation method for positively charged non-magnetic toner

Info

Publication number: WO2018188554A1
Application number: PCT/CN2018/082331
Authority: WO
Inventors: 袁誉炎; 吴校荣; 于普海
Original assignee: 珠海思美亚碳粉有限公司
Priority date: 2017-04-12
Filing date: 2018-04-09
Publication date: 2018-10-18
Also published as: CN106842841A

Abstract

Provided is a preparation method for a positively charged non-magnetic toner, wherein the positively charged non-magnetic toner includes a toner masterbatch and an additive. The toner masterbatch comprises 100 parts by weight of a styrene-acrylic resin, 3 parts by weight of a mold release agent, 6 parts by weight of a coloring agent, and 3 parts by weight of a charge controlling agent. The additive comprises 0.5 parts by weight of a small particle size hydrophobic silica having a particle size of 7 nm to 20 nm, 0.4 parts by weight of a large particle size hydrophobic silica having a particle size of 40 nm to 200 nm, 0.7 parts by weight of barium titanate, and 0.3 parts by weight of a polymethyl methacrylate. The preparation method comprises a pre-mixing step and a post-mixing step.

Description

Method for preparing positively charged non-magnetic toner

Technical field

[0001] The present invention relates to a method of preparing a toner, and more particularly to a method of preparing a positively charged non-magnetic toner. The present invention is based on a Chinese invention patent whose application date is April 12, 2017, and whose application number is CN201710235981.1, the contents of which are incorporated herein by reference.

Background technique

[0002] Existing printers generally include two major categories, laser printers and inkjet printers. Laser printers are widely used in office workplaces, especially in inkjet printers, which have the advantages of fast printing speed and low printing cost. In recent years, the popularity of color laser printing has become increasingly large, and the original toners (also commonly referred to as toners) used in laser printers tend to be expensive and limit the use of users.

[0003] The compatible consumables produced by general consumables companies are favored by the majority of users because of their low price. However, the researchers are licking the toner of the TN580 toner cartridge of the Brother Laser Printer HL-5240 printer, which is prone to OPC during the printing test. Problems such as ghosting, bottom ash and blackboard smearing, especially in the late development of the life test, the development roller has a poor powder, and the blackboard has a serious tailing. It is difficult to completely solve the above problem only by adjusting the toner formulation and changing the additive.

technical problem

[0004] An object of the present invention is to provide a method for preparing a positively-charged non-magnetic toner having a good printing effect.

[0005] Technical solutions

[0006] In order to achieve the above object, the present invention provides a method for preparing a positively-charged non-magnetic toner, wherein the positively-charged non-magnetic toner includes a toner master batch and an additive; and the preparation method includes a pre-mixing step and a post-mixing step; The premixing step includes first mixing the toner masterbatch in a mixer at 600 rpm for 2 minutes and then mixing at 1200 rpm for 2 minutes; the postmixing step includes, first, the premixing step. An additive was added to the obtained toner master batch mixture, and mixed in a mixer at 600 rpm for 2 minutes to 3 minutes, and then mixed at 1200 rpm for 2 minutes to 4 minutes. [0007] Further, the toner master batch comprises 100 parts by weight of styrene-acrylic resin, 3 parts by weight of a release agent,

6 parts by weight of the colorant and 3 parts by weight of the charge control agent.

[0008] A further solution is that the additive comprises 0.5 parts by weight of small particle size hydrophobic silica having a particle diameter of 7 nm to 20 nm, and 0.4 parts by weight of large particle size hydrophobic dioxide having a particle diameter of 40 nm to 200 nm. Silicon, 0.7 parts by weight of barium titanate and 0.3 parts by weight of polymethyl methacrylate.

[0009] A further solution is that in the post-mixing step, the mixture is first mixed at 600 rpm for 2 minutes and then at 1200 rpm for 2 minutes.

[0010] An alternative is to mix the mixture for 3 minutes at 600 rpm for 3 minutes and then for 2 minutes at 1200 rpm.

[0011] An alternative solution is to first mix at 600 rpm for 3 minutes and then at 1200 rpm for 3 minutes.

[0012] Alternatively, in the post-mixing step, the mixture is first mixed at 600 rpm for 3 minutes and then at 1200 rpm for 4 minutes.

[0013] Further, the pre-mixing step further comprises: a melt-kneading step of melt-kneading the mixed toner masterbatch mixture into a kneaded product in a kneader to control the temperature of the kneading at 100 degrees Celsius to Between 140 degrees Celsius; a cooling step, cooling the kneaded material to room temperature; a pulverizing and grading step, pulverizing the cooled kneaded material into granules, and grading a toner masterbatch having a diameter of 5 μm to 20 μm in the granules.

[0014] Still further, the post-mixing step further comprises: a screening step of sieving the toner masterbatch and the additive mixture obtained by post-mixing to remove coarse particles, the mesh number of which is 80 mesh to 150 mesh, preferably 100 Head.

Problem solution

Advantageous effects of the invention

Beneficial effect

[0015] The beneficial effects of the present invention are: by adding an additive to the toner masterbatch to change the charge amount and fluidity of the toner masterbatch, and premixing the toner masterbatch by a pre-mixing step, and passing the post-mixing The step of post-mixing the toner masterbatch and the additive changes the distribution and embedding of the additive in the positively charged non-magnetic toner, and the same can also change its charge amount and fluidity. The invention combines the selection of raw materials and the mixing process to prepare a positively charged non-magnetic toner having good printing quality.

Brief description of the drawing DRAWINGS

[0016] FIG. 1 is a formulation of four sets of positively charged non-magnetic toner embodiments of different compositions and levels.

2 is a print test result table of the positively-charged non-magnetic toners of Examples 1 to 4.

3 is a table of premixing process parameters for premixing the toner master batches of Example 4 in three groups. [0018] FIG.

4 is a table showing the results of printing test of the toner master batches of the three groups of the premixed Example 4. [0019] FIG.

5 is a post-mixing process parameter table in which the additive of Example 4 is added to the toner master batch obtained by the third group premixing process for post-mixing test. [0020] FIG.

6 is a print test result table of a positively charged non-magnetic toner obtained by post-mixing.

[0022] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Embodiments of the invention

[0023] The positively-charged non-magnetic toner of the present invention includes a toner masterbatch including a styrene-acrylic resin, a mold release agent, a colorant, and a charge control agent, and the additive includes silica, barium titanate, and an additive. Polymethyl methacrylate, the inventors prepared a total of four sets of positively charged non-magnetic toners by adjusting the formula. The content of each component is shown in Fig. _{1 (),} wherein the particle size of fine-grained silica is from 7 nm to 20 nm. Between, the particle size of the large particle silica is between 40 nm and 200 nm, and the surfaces of the fine particle silica and the large particle silica are both subjected to hydrophobic treatment. In the present invention, the coloring agent may be used in addition to carbon black, such as cyanine black, ferrite, aniline black, etc., and the wax used for the release agent may be paraffin wax, low molecular weight polypropylene wax, low molecular weight polyethylene wax, and Brazilian palm. A wax or the like, a charge control agent may be a quaternary ammonium salt or the like in addition to the oil-soluble aniline black.

[0024] The positively charged non-magnetic toners of Examples 1 to 4 were placed in a TN580 toner cartridge, and a printing test was performed on an HL-5240 printer. The test results are shown in FIG.

[0025] wherein, OPC ghosting refers to a phenomenon in which repetitive characters appear below the printed text.

[0026] BG is the bottom gray value, and bottom ash refers to the case where the non-developing area is grayed out, and the value of the blank area on the printing paper and the area covered by the additional paper (the untransferred area) can be measured by the gradation meter. The difference between the values of the values is obtained. The smaller the value of BG, the better the printing effect.

[0027] Blackboard smearing refers to printing a full blackboard, and the situation under the blackboard is grayed out.

[0028] It can be seen that the quality of the positively charged non-magnetic toner prepared according to the formulation of Example 4 is the best, but there is still a phenomenon of OPC ghosting and blackboard smearing. [0029] The inventors continued to study the formulation of Example 4, and solved the above problems thoroughly by the improvement of the process.

[0030] Premixing process: The toner master batch of Example 4 was subjected to three sets of premixing tests in accordance with the formulation in Table 1, and the premixing process is shown in Fig. 3. Wherein, R1 represents the rotational speed 1, the unit rpm is the revolution/minute, T1 represents the inter-turn of R1, and the unit is minute; R1 represents the rotational speed 2, and the unit is also the revolution/minute, and T2 represents the inter-turn of R2, and the unit is minute.

[0031] The first group: 100 parts of styrene resin, 3 parts of wax, 3 parts of oil-soluble aniline black and 6 parts of carbon black in a mixer (such as a Henschel mixer) at 600 rpm The rotation speed is mixed for 5 minutes to form a toner masterbatch mixture; then the mixed toner masterbatch mixture is melt-kneaded into a kneaded product in a kneader (such as a parallel twin-screw kneader) to control the kneading temperature. Between 100 degrees Celsius and 140 degrees Celsius; then cooling the mixture to room temperature; finally, pulverizing the cooled kneaded material into granules, and grading the toner masterbatch having a diameter of 5 micrometers to 20 micrometers in the particles .

[0032] Group 2: 100 parts of styrene resin, 3 parts of wax, 3 parts of oil-soluble aniline black and 6 parts of carbon black in a mixer (such as a Henschel mixer) at 1200 rpm The rotation speed is mixed for 5 minutes to form a toner masterbatch mixture; then the mixed toner masterbatch mixture is melt-kneaded into a kneaded product in a kneader (such as a parallel twin-screw kneader) to control the kneading temperature. Between 100 degrees Celsius and 140 degrees; the mixture is then cooled to room temperature; finally, the cooled kneaded material is pulverized into granules, and a toner masterbatch having a diameter of 5 micrometers to 20 micrometers is fractionated in the granules. .

[0033] The third group: 100 parts of styrene resin, 3 parts of wax, 3 parts of oil-soluble aniline black and 6 parts of carbon black in a mixer (such as a Henschel mixer) first 600 rpm / Mixing at a minute speed for 2 minutes, mixing at 1200 rpm for 5 minutes to form a toner masterbatch mixture; then mixing the mixed toner masterbatch in a mixer (such as a parallel twin-screw mixer) Melt and knead into a kneaded product, control the mixing temperature between 100 ° C and 140 ° C; then cool the kneaded material to room temperature; finally, the cooled kneaded material is pulverized into particles and classified in the particles A toner masterbatch having a diameter of from 5 micrometers to 20 micrometers is produced.

[0034] The toner masterbatch obtained by the first group, the second group and the third group process is respectively loaded into the TN580 toner cartridge, and the printing test is performed on the HL-5240 printer. The test results are shown in FIG.

[0035] It can be seen from the test result of FIG. 4 that in the premixing process, the difference between the rotation speed and the turn has little effect on the OPC ghost and the BG value, and has a certain influence on the blackboard tailing, and the third group premixing process is solved. Blackboard trailing problem However, there is still the problem of OPC ghosting. The inventors conducted a post-mixing process test on the toner masterbatch obtained from the third premixing process.

[0036] Post-mixing process: The additive of Example 4 was added to the color masterbatch obtained in the third group of pre-mixing processes according to the formulation of Fig. 1 to carry out a post-mixing test, and the post-mixing process is shown in Fig. 5.

[0037] The fourth group: adding 0.5 parts by weight to the toner masterbatch obtained in the third group premixing process, having a particle diameter of 7 nm to 2

0 nm of small particle size hydrophobic silica, 0.4 parts by weight of large particle size hydrophobic silica having a particle diameter of 40 nm to 200 nm, 0.7 part by weight of barium titanate, and 0.3 part by weight of polymethyl methacrylate The ester is mixed in a mixer (such as a Henschel mixer) at 600 rpm for 2 minutes, then mixed at 1200 rpm for 2 minutes, and the mixture is sieved to remove coarse particles. The number is 80 mesh to 150 mesh, preferably 1

00 mesh, a positively charged non-magnetic toner Al was obtained.

[0038] The fifth group: adding 0.5 parts by weight to the toner masterbatch obtained in the third group premixing process, having a particle diameter of 7 nm to 2

0 nm of small particle size hydrophobic silica, 0.4 parts by weight of large particle size hydrophobic silica having a particle diameter of 40 nm to 200 nm, 0.7 part by weight of barium titanate, and 0.3 part by weight of polymethyl methacrylate The ester is mixed in a mixer (such as a Henschel mixer) at 600 rpm for 3 minutes, then mixed at 1200 rpm for 2 minutes, and the mixture is sieved to remove coarse particles. The number is 80 mesh to 150 mesh, preferably 1

At 00 mesh, a positively charged non-magnetic toner A2 was obtained.

[0039] The sixth group: adding 0.5 parts by weight to the toner masterbatch obtained in the third group premixing process, having a particle diameter of 7 nm to 2

0 nm of small particle size hydrophobic silica, 0.4 parts by weight of large particle size hydrophobic silica having a particle diameter of 40 nm to 200 nm, 0.7 part by weight of barium titanate, and 0.3 part by weight of polymethyl methacrylate The ester is mixed in a mixer (such as a Henschel mixer) at 600 rpm for 3 minutes, then mixed at 1200 rpm for 3 minutes, and the mixture is sieved to remove coarse particles. The number is 80 mesh to 150 mesh, preferably 1

At 00 mesh, a positively charged non-magnetic toner A3 was obtained.

[0040] Group 7: adding 0.5 parts by weight to the toner masterbatch obtained in the third group premixing process, having a particle diameter of 7 nm to 2

0 nm of small particle size hydrophobic silica, 0.4 parts by weight of large particle size hydrophobic silica having a particle diameter of 40 nm to 200 nm, 0.7 part by weight of barium titanate, and 0.3 part by weight of polymethyl methacrylate The ester is mixed in a mixer (such as a Henschel mixer) at 600 rpm for 3 minutes, then mixed at 1200 rpm for 4 minutes, and the mixture is sieved to remove coarse particles. The number is 80 mesh to 150 mesh, preferably 1

At 00 mesh, a positively charged non-magnetic toner A4 was obtained. [0041] The positive non-magnetic toners A1, A2, A3, and A4 were respectively loaded into a TN580 toner cartridge, and a printing test was performed on the HL-5240 printer. The test results are shown in FIG.

[0042] From the test results of FIG. 6, it can be seen that in the post-mixing process, the difference between the rotational speed and the turn-to-turn affects the OPC ghost and the blackboard tailing because the post-mixing process affects the additive in the positively-charged non-magnetic toner. Distribution and embedding. Among them, the positive electric non-magnetic toner obtained by the sixth group of post-mixing process has the best quality, and solves the problem of the original toner.

[0043] In summary, the bursting process of the positively-charged non-magnetic toner is the result of the selection of the raw materials, the process and the equipment, and the slight difference in the process affects the charge amount and fluidity of the toner. Finally, it is reflected in the printing effect. The invention successfully solves the problems of OPC ghosting, bottom ash and blackboard smearing appearing in the HL-5240 printer by the selection of materials and the improvement of the process.

[0044] The technical idea of the present invention is not limited to the above embodiments, and many different specific solutions can be obtained according to the concept of the present invention, such as adjusting the ratio of each material within a reasonable range, and the speed of mixing the mixing and mixing. Such minor changes and equivalent transformations are intended to be included within the scope of the claims.

Industrial Applicability

[0046] A method for preparing a positively-charged non-magnetic toner of the present invention, by adding an additive to a toner masterbatch to change a charge amount and fluidity of a toner master batch, and performing a toner master batch by a pre-mixing step Premixing, post-mixing the toner masterbatch and additives through a post-mixing step, changing the distribution and embedding of the additive in the positively charged non-magnetic toner, and also changing the charge amount and fluidity. The invention combines the selection and mixing process of the raw materials to prepare a positively charged non-magnetic toner with good printing quality. The positive electroless non-magnetic toner prepared by the present invention is loaded into a toner cartridge for printing test, and can solve the problems of OPC ghosting, bottom ash, and blackboard smearing which are often caused by the existing powder cartridge.

Claims

Claim

A method for preparing a positively-charged non-magnetic toner, characterized in that:

The positively charged non-magnetic toner includes a toner master batch and an additive;

The preparation method includes a pre-mixing step and a post-mixing step;

The premixing step includes:

The toner masterbatch was mixed in a mixer at 600 rpm for 2 minutes, and then mixed at 1 200 rpm for 2 minutes;

The post-mixing step includes:

Adding the additive to the toner masterbatch mixture obtained in the pre-mixing step, mixing in a mixer at 600 rpm for 2 minutes to 3 minutes, and then mixing at 1200 rpm for 2 minutes. Up to 4 minutes.

The preparation method according to claim 1, wherein:

The toner master batch comprises 100 parts by weight of a styrene-acrylic resin, 3 parts by weight of a releasing agent, 6 parts by weight of a coloring agent, and 3 parts by weight of a charge control agent.

The preparation method according to claim 2, wherein:

The additive comprises 0.5 parts by weight of a small particle size hydrophobic silica having a particle diameter of 7 nm to 20 nm, 0.4 parts by weight of a large particle size hydrophobic silica having a particle diameter of 40 nm to 200 nm,

0.7 parts by weight of barium titanate and 0.3 parts by weight of polymethyl methacrylate.

The preparation method according to any one of claims 1 to 3, characterized in that:

In the post-mixing step, the mixture was mixed at 600 rpm for 2 minutes and then mixed at 1200 rpm for 2 minutes.

In the post-mixing step, the mixture was mixed at 600 rpm for 3 minutes and then mixed at 1200 rpm for 2 minutes.

In the post-mixing step, the mixture was mixed at 600 rpm for 3 minutes and then mixed at 1200 rpm for 3 minutes.

The preparation method according to any one of claims 1 to 3, characterized in that: In the post-mixing step, the mixture was mixed at 600 rpm for 3 minutes and then mixed at 1200 rpm for 4 minutes.

[Claim 8] The preparation method according to any one of claims 1 to 7, characterized in that:

The premixing step further includes

In the melt-kneading step, the mixed toner masterbatch mixture is melt-kneaded into a kneaded product in a kneader, and the temperature for controlling the kneading is between 100 degrees Celsius and 140 degrees Celsius;

a cooling step of cooling the kneaded material to room temperature;

The pulverization and classification step, the cooled kneaded product is pulverized into granules, and a toner master batch having a diameter of 5 μm to 20 μm is classified in the granules.

[Claim 9] The preparation method according to any one of claims 1 to 8, characterized in that:

The post-mixing step further includes

In the screening step, the toner masterbatch and the additive mixture obtained by post-mixing are sieved to remove coarse particles, and the mesh number is between 80 mesh and 150 mesh.

[Claim 10] The preparation method according to claim 9, wherein:

The mesh number is 100 mesh.