Toner with high fixability and preparation method thereof

Abstract

The invention relates to a high-fixability toner, and relates to the field of electrostatic charge image developing toners for printers, copying machines and the like. The invention relates to a high-fixability toner which comprises the following raw materials in parts by weight: 70-85 parts of bonding resin; 4-7 parts of a coloring agent; 2-3 parts of a charge additive; 2-5 parts of an external additive; 6-9 parts of a release agent; wherein the bonding resin is prepared from the following raw materials in parts by weight: 3-8 parts of glycidyl methacrylate; 75 to 80 parts of styrene; 15 to 25 parts of n-butyl methacrylate; 1 to 3 parts of isophorone diisocyanate; and 0.5-1 part of an initiator. According to the present invention, the fixing property and the demolding property of the toner can be balanced, and the toner has excellent fixing property and excellent fixing fastness.

Description

Technical Field

[0001] The present invention relates to the field of toner for developing electrostatic charge images in printers, copiers, etc., and in particular to a toner with strong fixing property and a preparation method thereof. Background Art

[0002] Printers and copiers contain image forming devices, which use charging means to uniformly charge the image forming area on the surface of the image carrier, use exposure means to write to the image carrier, and use development means to form an image on the image carrier using friction-charged toner. The image on the image carrier is then directly transferred to the printing paper sent by the paper feeding means by the transfer means, and the image is fixed on the printing paper by the fixing means. Toner is a consumable material such as carbon water and ink used in printers and copiers, which is used to form an image on paper.

[0003] Toners are usually composed of a significant amount of binder resin, release agent, colorant, charge additive and external additive. The toner adheres to the paper surface under pressure and temperature with the help of the binder resin, the charge additive is used to control the charge amount, increase the charging rate or improve the stability of the charge, and the external additive is used to improve the fluidity or adhesion of the toner.

[0004] The fixability of toner refers to the ability of toner to be stably fixed on the image carrier after forming an image on the image carrier, and not to fall off, fade or diffuse. Traditional toners have weak fixability and poor stability, but when a curing agent is used to promote the adhesion of toner to the image carrier, the release property of the toner will be affected, and it is impossible to find a balance between fixability and release property. Summary of the invention

[0005] In order to balance the fixability and release properties of a toner, the present application provides a toner with strong fixability and a method for preparing the same.

[0006] The present application provides a strong fixing toner and a preparation method thereof using the following technical solutions: In a first aspect, the present application provides a toner with strong fixing properties, comprising the following raw materials in parts by weight: 70-85 parts of adhesive resin; 4-7 parts of colorant; 2-3 parts of charging additive; 2-5 parts of external additives; 6-9 parts of release agent; The adhesive resin is prepared from the following raw materials in parts by weight: 3-8 parts of glycidyl methacrylate; Styrene 75-80 parts; 15-25 parts of n-butyl methacrylate; 1-3 parts of isophorone diisocyanate; Initiator 0.5-1 part.

[0007] By adopting the above technical scheme, by selecting styrene, glycidyl methacrylate and n-butyl methacrylate for polymerization, epoxy groups exist in the polymerized resin, and the polymerization reaction continues after isophorone diisocyanate is added, so that the glass transition temperature and hydroxyl value of the polymerized adhesive resin are easy to control, and the weight average molecular weight distribution Mw / Mn is moderate.

[0008] By controlling the adhesive resin, the adhesive resin has good stability and can be stably fixed on the image carrier to form an image. The adhesive resin is not prone to diffusion. The toner formed with the colorant, charging additive, external additive and release agent can be stably attached to the image carrier after the image is formed. It is not easy to fall off, fade or diffuse. It has excellent fixing property and fixing fastness. At the same time, it does not affect the ability of the toner to be detached from the printing equipment and has good demolding properties.

[0009] Preferably, the adhesive resin has a glass transition temperature of 60-75° C. and a number average molecular weight of 3000-6000.

[0010] By adopting the above technical solution, the glass transition temperature and the number average molecular weight are restricted, so that the binder resin can be fully cured and fixed, and at the same time, the heat resistance and dispersion performance of the toner are improved.

[0011] Preferably, the external additive is one or more of fumed silica, titanium dioxide, barium titanate, titanate coupling agent, and silane coupling agent.

[0012] By adopting the above technical solution, the external additives are attached to the surface of the adhesive resin particles, which is beneficial to improving the fluidity of the toner, facilitating the formation of images on the image carrier, and improving the low-temperature fixing property of the toner.

[0013] Preferably, the external additive is a mixture of fumed silica and isopropyl tristearate titanate coupling agent in a weight ratio of 1:(0.6-1), wherein the specific surface area of ​​the fumed silica is 50-80 m 2 / g.

[0014] By adopting the above technical scheme, fumed silica is selected to be attached to the surface of the adhesive resin particles and used as a surface treatment agent between the toner and the image carrier to improve the fluidity and fixing fastness of the toner. The isopropyl tristearate titanate coupling agent is beneficial to improving the bonding force between the fumed silica and the adhesive resin particles, making the toner more stable.

[0015] Preferably, the charging additive is selected from one or more of aniline black, distearate dimethylamine methyl sulfonate, and sodium trifluoromethane sulfonate.

[0016] By adopting the above technical solution, the charging additive is used to control the charge amount of the toner, thereby controlling the friction charging performance of the toner.

[0017] Preferably, the release agent is selected from one or more of polyethylene wax, polypropylene wax, carnauba wax, oxidized polyethylene wax, and microcrystalline wax.

[0018] By adopting the above technical solution, a release agent is selected to reduce the viscosity of the toner, which facilitates the separation of the toner from the printing equipment for transfer and ensures the dispersion of the release agent in the adhesive resin.

[0019] Preferably, the colorant is one or more of carbon black, aniline black, and monoazo black dye.

[0020] By adopting the above-mentioned technical scheme, the colorant is used to provide color so that the toner forms a visible image through development.

[0021] Preferably, the initiator is one or more of azobisisobutyronitrile, tert-butyl hydroperoxide, and isobutyl peroxide.

[0022] By adopting the technical scheme, the polymerization reaction of styrene, dehydrated glycerol methacrylate and n-butyl methacrylate is promoted by an initiator.

[0023] In a second aspect, the present application provides a method for preparing a toner with strong fixing properties, comprising the following steps: Premixing: Mix the adhesive resin, colorant, release agent and charging additive at high speed at 900-1200 rpm for 3-5 minutes; Melt mixing: melt mixing the pre-mixed mixture at a mixing temperature of 100-130°C, and slice it after cooling; Crushing and grading: The mixture obtained by slicing is coarsely crushed into particles, and then finely crushed and graded using a jet airflow crushing and classifying machine to obtain graded particles; Post-mixing: Stir and mix the graded particles with the external additives at a stirring speed of 600-800 rpm for 4-7 minutes; Screening: The particles obtained after the mixing are screened through a sieve to obtain a toner.

[0024] By adopting the above technical scheme, a stable, durable and strong fixing toner is obtained by melt-kneading a binder resin, a colorant, a release agent and a charge additive, coarsely pulverizing the obtained mixture, adding an external additive and coarsely pulverizing and classifying.

[0025] Preferably, the adhesive resin is prepared by the following steps: Styrene and xylene are mixed and placed in a flask, nitrogen is introduced, and an oil bath is heated to 130-140°C, and a mixture of glycidyl methacrylate, n-butyl methacrylate and part of the initiator is added dropwise for 3-4 hours, and the mixture is kept warm for reaction for 0.5-1 hour. After the remaining initiator is added dropwise, the polymerization is continued for 1-2 hours, and the solvent is removed by flash evaporation to obtain a polymerized resin; The polymer resin is supplied to a kneader, and isophorone diisocyanate is supplied to the kneader, kneading is performed at 160-180° C., and after cooling, an adhesive resin is obtained.

[0026] By adopting the above technical scheme, the initiator promotes the polymerization of monomers of glycidyl methacrylate, n-butyl methacrylate and styrene, and then isophorone diisocyanate is added for cross-linking at high temperature to achieve the synthesis of the adhesive resin, so that the cross-linking bonding of the adhesive resin is strong and more stable.

[0027] Preferably, the particle size of the classified particles is 5-15 μm, and the mesh number of the sieve is between 100 mesh and 150 mesh.

[0028] By adopting the above technical solution, the particle size of the toner is controlled, the effectiveness of the toner in the development process is ensured, and the imaging quality is guaranteed.

[0029] In summary, this application has the following beneficial effects: 1. By using styrene, glycidyl methacrylate and n-butyl methacrylate for polymerization, epoxy groups exist in the polymerized resin, and the polymerization reaction continues after adding isophorone diisocyanate, so that the glass transition temperature and hydroxyl value of the polymerized adhesive resin are easy to control, and the weight average molecular weight distribution Mw / Mn is moderate.

[0030] By controlling the adhesive resin, the adhesive resin has good stability and can be stably fixed on the image carrier to form an image. The adhesive resin is not prone to diffusion. The toner formed with the colorant, charging additive, external additive and release agent can be stably attached to the image carrier after the image is formed. It is not easy to fall off, fade or diffuse. It has excellent fixing property and fixing fastness. At the same time, it does not affect the ability of the toner to be detached from the printing equipment and has good demolding properties.

[0031] 2. Use fumed silica attached to the surface of the adhesive resin particles as a surface treatment agent between the toner and the printing medium to improve the fluidity and fixing fastness of the toner. Isopropyl tristearate titanate coupling agent is beneficial to improve the binding force between fumed silica and the adhesive resin particles, making the toner more stable. DETAILED DESCRIPTION

[0032] The present application is further described in detail below in conjunction with Examples 1-6 and Comparative Examples 1-2.

[0033] Preparation Example Preparation Example 1 An adhesive resin is prepared from the following raw materials in parts by weight: 3 parts of glycidyl methacrylate; Styrene 75 parts; 15 parts of n-butyl methacrylate; 1 part of isophorone diisocyanate; 0.5 parts of initiator, specifically azobisisobutyronitrile is selected as the initiator.

[0034] In this preparation example, the preparation method of the adhesive resin includes the following steps: Pass nitrogen into the flask, add styrene and 40 parts of xylene, stir and mix, and heat the oil bath to 130°C. Evenly mix glycidyl methacrylate, n-butyl methacrylate and 0.3 parts of initiator, and drop the mixture into the flask for 3 hours, and keep the temperature for 0.5 hours. Drop the remaining 0.2 parts of initiator into the flask and continue polymerization for 1 hour, and remove the solvent xylene by flash evaporation to obtain a polymerized resin; The polymerized resin was supplied to a kneader at a rate of 10 kg / hr, and isophorone diisocyanate was supplied to the kneader, kneaded at 160° C., and then cooled to obtain an adhesive resin.

[0035] The test results show that the glass transition temperature of the adhesive resin is 72°C, the number average molecular weight is 4500, and the weight average molecular weight distribution is 4.

[0036] Preparation Example 2 An adhesive resin is prepared from the following raw materials in parts by weight: Glycidyl methacrylate 8 parts; Styrene 80 parts; 25 parts of n-butyl methacrylate; 3 parts of isophorone diisocyanate; 1 part of initiator, wherein the initiator is specifically selected from tert-butyl hydroperoxide.

[0037] In this preparation example, the preparation method of the adhesive resin includes the following steps: A flask was filled with nitrogen, styrene and 50 parts of xylene were added and stirred, and the mixture was heated to 140°C in an oil bath. Glycidyl methacrylate, n-butyl methacrylate and 0.5 parts of initiator were mixed evenly, and the mixture was added dropwise to the flask for 4 hours, and the reaction was kept warm for 1 hour. The remaining 0.5 parts of initiator were added dropwise to the flask and the polymerization was continued for 2 hours. The solvent xylene was removed by flash evaporation to obtain a polymerized resin; The polymer resin was supplied to a kneader at a rate of 10 kg / hr, and isophorone diisocyanate was supplied to the kneader, kneaded at 180° C., and cooled to obtain an adhesive resin.

[0038] The test results show that the glass transition temperature of the adhesive resin is 70°C, the number average molecular weight is 4200, and the weight average molecular weight distribution is 4.

[0039] Preparation Example 3 An adhesive resin is prepared from the following raw materials in parts by weight: Glycidyl methacrylate 5 parts; Styrene 78 parts; 20 parts of n-butyl methacrylate; 2 parts of isophorone diisocyanate; 0.8 parts of initiator, specifically 0.5 parts of tert-butyl hydroperoxide and 0.3 parts of isobutyl peroxide.

[0040] In this preparation example, the preparation method of the adhesive resin includes the following steps: A flask was filled with nitrogen, styrene and 45 parts of xylene were added and stirred, and the mixture was heated to 135°C in an oil bath. Glycidyl methacrylate, n-butyl methacrylate and 0.5 parts of initiator were mixed evenly, and the mixture was added dropwise to the flask for 3.5 hours, and the reaction was kept warm for 1 hour. The remaining 0.3 parts of initiator were added dropwise to the flask and the polymerization was continued for 1.5 hours. The solvent xylene was removed by flash evaporation to obtain a polymerized resin; The polymer resin was supplied to the kneader at a rate of 10 kg / hr, and isophorone diisocyanate was supplied to the kneader, kneaded at 170° C., and cooled to obtain an adhesive resin.

[0041] The test results show that the glass transition temperature of the adhesive resin is 69°C, the number average molecular weight is 3800, and the weight average molecular weight distribution is 3. Example

[0042] Example 1 A toner with strong fixing property comprises the following raw materials in parts by weight: 70 parts of an adhesive resin. In this embodiment, the adhesive resin is the adhesive resin prepared in Preparation Example 1; 4 parts of colorant. In this embodiment, the colorant is carbon black; 2 parts of a charging additive. In this embodiment, the charging additive is aniline black; 2 parts of external additives. In this embodiment, the external additive is fumed silica, and the specific surface area of ​​fumed silica is 30-40m 2 / g; 6 parts of release agent. In this embodiment, the release agent is polyethylene wax, the molecular weight of the polyethylene wax is 2000, and the melting point of the polyethylene wax is 110°C.

[0043] A method for preparing a toner with strong fixing properties comprises the following steps: Premixing: Put the adhesive resin, colorant, release agent and charging additive into a mixer and stir at high speed at 900 rpm for 3 minutes; Melt mixing: the pre-mixed mixture is put into a mixer for melt mixing at a mixing temperature of 100°C, and sliced ​​after cooling; crushing and classification: the sliced ​​mixture is coarsely crushed into particles, the particle size of the coarsely crushed particles is 1-2mm, and finely crushed and classified by a jet airflow crushing and classifying machine to obtain graded particles, the particle size of the graded particles is 5-15μm; Post-mixing: Stir and mix the graded particles with the external additives at a stirring speed of 600 rpm for 4 min; Screening: The particles obtained by post-mixing are screened through a sieve with a mesh size of 100 to obtain a toner.

[0044] Example 2 A toner with strong fixing property comprises the following raw materials in parts by weight: 85 parts of a bonding resin. In this embodiment, the bonding resin is the bonding resin prepared in Preparation Example 2; 7 parts of colorant. In this embodiment, the colorant is ferrosoferric oxide; 3 parts of a charging additive. In this embodiment, the charging additive is distearate dimethylamine methyl sulfonate; 5 parts of external additives. In this embodiment, the external additives are titanium dioxide and barium titanate, specifically 3 parts of titanium dioxide and 2 parts of barium titanate; 9 parts of release agent. In this embodiment, the release agent is carnauba wax, and the melting point of carnauba wax is 82°C.

[0045] A method for preparing a toner with strong fixing properties comprises the following steps: Premixing: Put the adhesive resin, colorant, release agent and charging additive into a mixer and stir at high speed at 1200 rpm for 5 minutes; Melt mixing: the pre-mixed mixture is put into a mixer for melt mixing at a mixing temperature of 130°C, and sliced ​​after cooling; crushing and grading: the sliced ​​mixture is coarsely crushed into particles, the particle size of the coarsely crushed particles is 1-2mm, and finely crushed and graded with a jet airflow crushing and classifying machine to obtain graded particles, the particle size of the graded particles is 5-15μm; Post-mixing: Stir and mix the graded particles with the external additives at a stirring speed of 800 rpm for 7 minutes; Screening: The particles obtained by post-mixing are screened through a sieve with a mesh size of 150 to obtain a toner.

[0046] Example 3 A toner with strong fixing property comprises the following raw materials in parts by weight: 80 parts of an adhesive resin. In this embodiment, the adhesive resin is the adhesive resin prepared in Preparation Example 3; 5 parts of colorant. In this embodiment, the colorant is a monoazo black dye; 2.5 parts of a charging additive. In this embodiment, the charging additive is sodium trifluoromethanesulfonate; 4 parts of external additives. In this embodiment, the external additive is silane coupling agent KH-550; 8 parts of release agent. In this embodiment, the release agent is oxidized polyethylene wax, the molecular weight of the oxidized polyethylene wax is 2400, and the melting point of the oxidized polyethylene wax is 105°C.

[0047] A method for preparing a toner with strong fixing properties comprises the following steps: Premixing: Put the adhesive resin, colorant, release agent and charging additive into a mixer and stir at high speed at 1000 rpm for 4 minutes; Melt mixing: the pre-mixed mixture is put into a mixer for melt mixing at a mixing temperature of 110°C, and sliced ​​after cooling; crushing and grading: the sliced ​​mixture is coarsely crushed into particles, the particle size of the coarsely crushed particles is 1-2mm, and finely crushed and graded with a jet airflow crushing and classifying machine to obtain graded particles, the particle size of the graded particles is 5-15μm; Post-mixing: Stir and mix the graded particles with the external additives at a stirring speed of 700 rpm for 5 min; Screening: The particles obtained by post-mixing are screened through a sieve with a mesh size of 120 to obtain a toner.

[0048] Example 4 The difference between this embodiment and the first embodiment is that the selection of the external additive in the toner raw material is different.

[0049] The external additive of this embodiment is a mixture of fumed silica and isopropyl tristearate titanate coupling agent, specifically 1 part of fumed silica and 1 part of isopropyl tristearate titanate coupling agent, and the specific surface area of ​​fumed silica is 50-80m 2 / g.

[0050] Example 5 The difference between this embodiment and the first embodiment is that the selection of the external additive in the toner raw material is different.

[0051] The external additive of this embodiment is a mixture of fumed silica and isopropyl tristearate titanate coupling agent, specifically 1.25 parts of fumed silica and 0.75 parts of isopropyl tristearate titanate coupling agent, and the specific surface area of ​​fumed silica is 50-80 m 2 / g.

[0052] Example 6 The difference between this example and Example 1 is that the selection of the external additive in the toner raw material is different.

[0053] The external additive of this embodiment is a mixture of fumed silica and isopropyl tristearate titanate coupling agent, specifically 1 part of fumed silica and 1 part of isopropyl tristearate titanate coupling agent, and the specific surface area of ​​fumed silica is 30-50m 2 / g.

[0054] Comparative Example Comparative Example 1 This comparative example is different from Example 1 in that the binder resin in the toner raw material is different.

[0055] The adhesive resin of this comparative example is styrene-acrylate resin, specifically styrene-butyl acrylate resin manufactured by FUJIKURAKASEI CO.LTD., with a weight average molecular weight of 270,000 and a glass transition temperature of 70°C.

[0056] The toner is prepared in the same manner as in Example 1.

[0057] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that the binder resin in the toner raw material is different.

[0058] When preparing the adhesive resin of this comparative example, no isophorone diisocyanate is added to the raw materials, and the adhesive resin is obtained by polymerization of styrene, glycidyl methacrylate and n-butyl methacrylate.

[0059] The test results show that the glass transition temperature of the adhesive resin is 66°C, the number average molecular weight is 4000, and the weight average molecular weight distribution is 3.

[0060] Performance Test: 1. Heat stability: 10 g of the toners of Examples 1-6 and Comparative Examples 1-2 were weighed in an propylene cup and allowed to stand for 24 h in an environment with a temperature of 50°C and a humidity of 50%. The toner agglomeration was visually determined and classified into three grades, A, B, and C, from good to bad. The results were recorded in Table 1.

[0061] 2. Low-temperature fixability: The toners of Examples 1 to 6 and Comparative Examples 1 to 2 were filled in a printer with a fixing machine removed, and the toners were printed on a paper surface at a coverage rate of 1 mg / cm2 to form an image, so that the paper surface passed through the heating roller at a fixing speed of 150 mm / s and a temperature of the heating roller in the range of 120-170°C at intervals of 5°C. Whether cold offset occurred on the image was visually inspected, and the occurrence temperature of cold offset was measured and recorded in Table 1.

[0062] 3. Fixing fastness: Use a printer filled with the toner of Examples 1-6 and Comparative Examples 1-2 to make a copy based on GB / T13334-2008 as the original, cut a 30 mm wide paper strip with any solid circle with a diameter of 6 cm in the middle as the center line, and measure the density value D1 of the solid circle with a reflection densitometer.

[0063] Place the sample on the friction tester, with the test point located at the center of the friction table, rub it back and forth twice, and re-measure the reflection density value D2. Calculate the fixing fastness = D2 / D1×100%, and put the fixing fastness results in Table 1.

[0064] 4. Strength: Use a developer filled with the toners of Examples 1-6 and Comparative Examples 1-2 to continuously print 3,000 solid images with an area ratio of 50%. Observe whether there is toner breakage caused by the cleaning scraper and film contamination caused by toner breakage on the photoreceptor, classify them, and record the results in Table 1.

[0065] A+: Toner breakage and filming were not observed; A: Slight breakage was observed, but no filming was observed; A-: Toner breakage and filming were observed.

[0066] Table 1 Sample Heat stability Low temperature fixability Fixing firmness strength Example 1 A 140℃ 94.7％ A+ Example 2 A 145℃ 94.2％ A+ Example 3 A 145℃ 94.5％ A+ Example 4 A 120℃ 97.3％ A+ Example 5 A 120℃ 97.1％ A+ Example 6 A 140℃ 95.0％ A+ Comparative Example 1 B 160℃ 91.4％ A Comparative Example 2 B 165℃ 92.6％ A According to the data in the table, the toner prepared in the present application has good strength and fixability, and is excellent in low-temperature fixability, fixability, and heat-resistant storage, and can be suitably used as a toner for electrostatic image development used in electronic photography, electrostatic recording, electrostatic printing, etc.

[0067] The present application improves the binder resin in the toner raw material, and selects styrene, glycidyl methacrylate, n-butyl methacrylate and isophorone diisocyanate as monomers for polymerization, so as to control the thermodynamic properties such as the glass transition temperature and weight average molecular weight distribution of the binder resin, so that the binder resin has good curing performance and can be well adhered to media such as paper.

[0068] This specific implementation manner is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the specific implementation manner as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A toner with strong fixing property, characterized in that: The invention comprises the following raw materials in parts by weight: 70-85 parts of adhesive resin; 4-7 parts of colorant; 2-3 parts of charging additive; 2-5 parts of external additives; 6-9 parts of release agent; The adhesive resin is prepared from the following raw materials in parts by weight: 3-8 parts of glycidyl methacrylate; Styrene 75-80 parts; 15-25 parts of n-butyl methacrylate; 1-3 parts of isophorone diisocyanate; Initiator 0.5-1 part.

2. A toner with strong fixing property according to claim 1, characterized in that: The adhesive resin has a glass transition temperature of 60-75° C. and a number average molecular weight of 3000-6000.

3. A toner with strong fixing property according to claim 1, characterized in that: The external additive is selected from one or more of fumed silica, titanium dioxide, barium titanate, titanate coupling agent, and silane coupling agent.

4. A toner with strong fixing property according to claim 3, characterized in that: The external additive is a mixture of fumed silica and isopropyl tristearate titanate coupling agent in a weight ratio of 1:(0.6-1), wherein the specific surface area of ​​the fumed silica is 50-80 m 2 / g.

5. A toner with strong fixing property according to claim 1, characterized in that: The charging additive is selected from one or more of aniline black, distearate dimethylamine methyl sulfonate, and sodium trifluoromethane sulfonate.

6. A toner with strong fixing property according to claim 1, characterized in that: The release agent is selected from one or more of polyethylene wax, polypropylene wax, carnauba wax, oxidized polyethylene wax, and microcrystalline wax.

7. A toner with strong fixing property according to claim 1, characterized in that: The colorant is selected from one or more of carbon black, ferrosoferric oxide, and monoazo black dye.

8. The method for preparing a toner with strong fixing property according to any one of claims 1 to 7, characterized in that: The steps include: Premixing: Mix the adhesive resin, colorant, release agent and charging additive at high speed at 900-1200 rpm for 3-5 minutes; Melt mixing: melt mixing the pre-mixed mixture at a mixing temperature of 100-130°C, and slice it after cooling; Crushing and grading: The mixture obtained by slicing is coarsely crushed into particles, and then finely crushed and graded using a jet airflow crushing and classifying machine to obtain graded particles; Post-mixing: Stir and mix the graded particles with the external additives at a stirring speed of 600-800 rpm for 4-7 minutes; Screening: The particles obtained after the mixing are screened through a sieve to obtain a toner.

9. The method for preparing a toner with strong fixing property according to claim 8, characterized in that: The adhesive resin is prepared by the following steps: Styrene and xylene are mixed and placed in a flask, nitrogen is introduced, and an oil bath is heated to 130-140°C, and a mixture of glycidyl methacrylate, n-butyl methacrylate and part of the initiator is added dropwise for 3-4 hours, and the mixture is kept warm for reaction for 0.5-1 hour. After the remaining initiator is added dropwise, the polymerization is continued for 1-2 hours, and the solvent is removed by flash evaporation to obtain a polymerized resin; The polymer resin is supplied to a kneader, and isophorone diisocyanate is supplied to the kneader, kneading is performed at 160-180° C., and after cooling, an adhesive resin is obtained.

10. The method for preparing a toner with strong fixing property according to claim 8, characterized in that: The particle size of the classified particles is 5-15 μm, and the mesh number of the sieve is between 100 meshes and 150 meshes.