Toner containing insoluble and infusible conductive polymer

Abstract

The invention discloses a toner containing an insoluble and infusible conductive polymer. The toner can solve the problem that an existing toner is not resistant to thermal offset. According to the technical scheme, the method comprises the following steps: (1) firstly, performing electrochemical doping modification on a conductive polymer to improve the conductivity; (2) crushing a conductive polymer, and performing melt kneading on the crushed conductive polymer and low-melting-point and high-acid-value resin to obtain conductive polymer master batches which are easier to disperse; and (3) preparing the toner composition containing the insoluble and infusible conductive polymer by taking the conductive polymer master batch as an internal additive. The toner obtained by the invention has good thermal migration resistance, narrower charged distribution and good hue, the used materials are wide in source, the treatment method is simple and efficient, and the toner is suitable for large-scale production.

Description

Technical Field

[0001] This invention belongs to the technical field of electrostatic copying and developing consumables. Specifically, it relates to a toner containing an insoluble and infusible conductive polymer, including a method for modifying the conductive polymer and a method for applying it in the toner. Background Technology

[0002] With the development of low-temperature fixing technology for laser printers and the urgent need for energy conservation and emission reduction, toners used as developing consumables are required to have lower softening points and higher melt flow rates. However, this improvement often leads to thermal drift issues during cold starts (the process of shutting down the printer for a sufficient time to allow the fixing unit temperature to return to ambient temperature before restarting) and during long printing sessions. To address this, conventional technical solutions mainly include three approaches: first, increasing the degree of cross-linking in the resin to improve its cohesiveness, as exemplified by patent CN100565359C; second, using crystalline resins to improve the toner's creep resistance at high temperatures, as exemplified by patent CN102236275B; and third, selecting low-melting-point waxes to improve the toner's release properties and enhance its penetration into paper, as exemplified by patent CN101055435A.

[0003] However, the above methods also have certain limitations: First, the increase in resin crosslinking degree will inevitably lead to a deterioration in low-temperature fixing performance, and the crosslinked material generally has low charge properties, resulting in uneven charge distribution; Second, although crystalline resins are highly distinctive, they require careful screening and compatibility testing. If they have good compatibility with the original resin of the toner, the storage stability of the toner will decrease significantly. If the compatibility is too low, it will lead to cold migration, which is more difficult to operate and poses greater risks; Finally, for low-melting-point waxes, on the one hand, when using the melt-pulverization process to produce toners, the wax is prone to breakage at the wax interface during the pulverization process, resulting in wax accumulation on the surface of the toner. This not only affects the efficiency of the subsequent grading process, but also poses a greater challenge to the charge uniformity and storage stability of the toner. In addition, low-melting-point wax exposed on the surface of the toner often leads to serious defects such as adhesion to the carrier, organic photoconductor drum, cleaning scraper, and powder discharge blade, reducing the application performance of the toner.

[0004] To overcome the problems of existing technologies, it is necessary to find a polymer that can function similarly to the cross-linked structure in resin, possesses a certain electrical conductivity to improve its charging properties, and also exhibits good stability and insolubility to prevent dissolution or melting during the mixing process. Through extensive research and cross-disciplinary exploration, the inventors have discovered that conductive polymers can meet this requirement.

[0005] Conductive polymers are a class of high-molecular materials with significant electrical conductivity. Their unique physical and chemical properties make them promising for applications in energy, electronics, sensors, and other fields. First, the insolubility and infusibility of conductive polymers are among their most notable characteristics. Traditional polymers typically exhibit good solubility and melt processability, while conductive polymers often display poor solubility and meltability. This is because the introduction of special groups such as conjugated structures and dopants into the molecular chains of conductive polymers leads to enhanced intermolecular interactions, making the polymers difficult to dissolve in common solvents or melt under heating conditions. This insolubility and infusibility limits the processing and application of conductive polymers to some extent, but it also endows them with unique stability. According to literature reports, their thermogravimetric analysis shows stability up to 200℃ (Zuo S, Liu W, Yao C, et al. Preparation of polyaniline–polypyrrole binary composite nanotube using halloysite as hard-template and its characterization[J]. Chem. Eng. J.,2013, 228: 1092-1097.). Second, conductivity is the most crucial characteristic of conductive polymers. Through specific synthesis methods and doping treatments, conductive polymers can exhibit excellent electrical conductivity. Their conductivity mechanism is primarily based on the π-electron conjugated system within the polymer chain, achieving current conduction through the delocalization of electrons. Furthermore, the introduction of dopants can further modulate the conductivity of conductive polymers. Charge transfer and ion exchange between the dopant and the polymer chain cause the polymer chain to acquire a charge and generate conductive channels, thereby improving its conductivity.

[0006] The ease with which conductive polymers are doped is a significant source of their conductivity. Doping refers to the process of altering the electronic structure and conductivity of a conductive polymer by introducing dopants. Depending on the doping method, conductive polymer doping can be classified into p-type doping and n-type doping. P-type doping involves oxidation reactions that impart a positive charge to the polymer chains, accompanied by the insertion of anions. N-type doping, on the other hand, involves reduction reactions that impart a negative charge to the polymer chains, accompanied by the insertion of cations. However, this type of doping is susceptible to oxidation by air, leading to a decrease in conductivity and making it unsuitable for melt-blending processes. Furthermore, the type and concentration of dopants significantly affect the conductivity of conductive polymers. Appropriate dopant selection and doping processes can optimize the conductivity of conductive polymers to meet the requirements of specific applications. Electrochemical doping is characterized by its simplicity, scalability, and precise control over the doping level of polymers, making it highly suitable for industrial applications (Morvant MC, Reynolds J R. In situ conductivity studies of poly(3,4-ethylenedioxythiophene)[J].Synth. Met., 1998, 92: 57-61. Ma Chun'an, et al. Green Electrochemical Synthesis[M]. Beijing: Chemical Industry Press, 2016: 4-6.).

[0007] Due to the characteristics of conductive polymers, directly using commercially available or conventionally chemically oxidized conductive polymers results in relatively low conductivity and weak charge regulation capabilities, making it difficult to obtain uniformly charged toner particles. Furthermore, directly using conductive polymers as internal additives in toners leads to uneven mixing due to differences in density and structure, severely impacting the toner's resistance to thermal migration. Therefore, after selecting a conductive polymer, process compatibility must be considered to maximize its effectiveness. Summary of the Invention

[0008] In view of the aforementioned problems with the prior art, and the fact that the application of conductive polymers in toners is still in its infancy, the inventors have conducted extensive research to solve these problems. As a result, it has been found that the following objectives can be achieved through the present invention described below. The objective of the present invention is to provide a toner containing an insoluble and infusible conductive polymer that is resistant to thermal displacement, by improving the conductivity of the conductive polymer through electrochemical doping, and by preparing the conductive polymer into a masterbatch to improve its dispersion effect in adhesive resins.

[0009] The implementation scheme of the present invention to solve the above-mentioned technical problems is as follows.

[0010] This invention provides an insoluble and infusible conductive polymer, which is an electrochemically doped conductive polymer; The dopant used in electrochemical doping is p Type dopants, including but not limited to one or more selected from hydrofluoric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, boron trifluoride, boron trichloride, sulfuric acid, nitric acid, lithium perchlorate, sodium perchlorate, p-toluenesulfonic acid, sodium p-toluenesulfonate, sodium dodecylbenzenesulfonate, sodium polystyrene sulfonate, sodium nitrite, copper sulfate, copper nitrate, sodium tetrafluoroborate, tetrabutylphosphine sodium tetrafluoroborate, tetrabutylhexafluorophosphate, tetrabutylammonium hexafluorophosphate, sodium hexafluorophosphate, boron trifluoride ether, styrene sulfonic acid, polystyrene sulfonic acid, and carboxylated carbon nanotubes; The conductive polymer is selected from one or more of polypyrrole and its derivatives, polyaniline and its derivatives, polythiophene and its derivatives, and polycarbazole and its derivatives.

[0011] According to an embodiment of the present invention, the conductivity of the insoluble and infusible conductive polymer is... σ ≥100 S cm -1 For example, 100 S cm -1 ≤ σ ≤400 S cm -1 .

[0012] According to an embodiment of the present invention, the insoluble and infusible conductive polymer can be a micron, submicron, or nanomaterial, such as a microtube, nanotube, nanowire, microsphere, or submicron irregular particle.

[0013] According to embodiments of the present invention, "insoluble" means that the conductive polymer is insoluble in common solvents such as water, ethanol, acetone, toluene, tetrahydrofuran (THF), and dichloromethane; "non-melting" means that the conductive polymer does not melt below 200°C.

[0014] The present invention also provides a polymer masterbatch, which is obtained by melting the above-mentioned insoluble and infusible conductive polymer and resin.

[0015] According to an embodiment of the present invention, the resin is selected from one or two of polyester resin, styrene-acrylic resin, etc.

[0016] According to an embodiment of the present invention, the resin may be the same as or different from the binder resin of the toner composition; when it is different from the binder resin of the toner composition, a polyester resin with a softening point of 90~110°C, a melt index of 50~500 g / 10min, and an acid value of 15~35 mg KOH / g is preferred.

[0017] According to an embodiment of the present invention, the insoluble and infusible conductive polymer accounts for 10-50% by mass in the polymer masterbatch, for example, 20-40%.

[0018] The present invention also provides the use of the above-mentioned insoluble and infusible conductive polymer or polymer masterbatch in the preparation of toner compositions.

[0019] According to an embodiment of the present invention, the toner is a toner used for electrostatic development (electrophotographic development equipment).

[0020] The present invention also provides a method for preparing the above-mentioned insoluble and infusible conductive polymer, comprising the following steps: (1) A conductive polymer, anionic surfactant and water are mixed to form a conductive polymer dispersion; (2) The conductive polymer dispersion is subjected to ultrasonic treatment; (3) After step (2) is completed, a conductive polymer film is prepared; (4) The conductive polymer film is prepared as the working electrode, a platinum mesh is used as the counter electrode, and the electrolyte is... p Electrochemical doping was performed using an aqueous solution of a type of dopant and a potentiostat. (5) After step (4) is completed, remove the conductive polymer film from the working electrode and dry it; (6) The dried conductive polymer film is crushed.

[0021] According to embodiments of the present invention, the anionic surfactant includes, but is not limited to, one or more selected from sodium dodecylbenzenesulfonate, sodium dodecyl sulfonate, sodium dodecyl sulfate, alkyl aryl sulfonate, polyoxyethylene lauryl ether carboxylic acid, phenolic ether phosphate, sodium lauryl alcohol polyoxyethylene ether sulfate, and sodium alkyl allyl succinate sulfonate.

[0022] According to an embodiment of the present invention, in step (1), the amount of the anionic surfactant added (relative to the mass of the conductive polymer) is 0.5 to 5%, for example 1%, 2%, 3%, 4%, 5%.

[0023] According to an embodiment of the present invention, in step (4), the electrochemical doping is performed with the anode current set to positive and the current density set to 0.3~1.5 mA cm⁻¹. -2 The doping time is 10~120 s.

[0024] According to an embodiment of the present invention, the preparation method of the insoluble and infusible conductive polymer is as follows: (1) Weigh 100 g of conductive polymer particles, disperse them in 500 mL of deionized water, add 0.5-5% of anionic surfactant by mass of conductive polymer, stir for 5-30 min to obtain conductive polymer dispersion; (2) The conductive polymer dispersion is ultrasonically dispersed with an ultrasonic power of 200~600W for 5~20min; (3) Using a microporous filter membrane, the conductive polymer dispersion obtained in the above steps is filtered to obtain a conductive polymer film; (4) The conductive polymer film is used as the working electrode, and the platinum mesh is used as the counter electrode. The electrolyte contains 0.1~2 mol / L p Electrochemical doping was performed using an aqueous solution of a type-3 dopant and a potentiostat, with the anodic current set to positive and the current density ranging from 0.3 to 1.5 mA cm⁻¹. -2 The doping time is 10~120 s; (5) Remove the doped conductive polymer film from the working electrode and dry it under vacuum; (6) Use a grinder to pulverize the dried conductive polymer film, with a stirring speed of 1500~3500 rpm and a stirring time of 20~60 min, so as to finally obtain an insoluble and infusible conductive polymer powder.

[0025] The present invention also provides a method for preparing the above-mentioned polymer masterbatch, the method comprising the following steps: S1. Mix the insoluble and infusible conductive polymer and resin; S2. The mixture obtained in step S1 is melt-extruded; S3. After the material discharged from step S2 is cooled and pressed into tablets, it is crushed to obtain the polymer masterbatch.

[0026] According to an embodiment of the present invention, step S1 is carried out in a high-speed mixer with a filling amount of 30-50% and a rotation speed of 200-800 rpm.

[0027] According to an embodiment of the present invention, the melt extrusion temperature in step S2 is 70~125°C.

[0028] According to an embodiment of the present invention, step S2 is carried out in a mixer, which can be a twin-screw extruder or an open-roll kneader. When using an open-roll kneader, the mixing temperature needs to be lowered by 5~15℃.

[0029] According to an embodiment of the present invention, step S3 involves crushing to obtain particles with a particle size of 0.5~2 mm.

[0030] According to an embodiment of the present invention, the method for preparing the polymer masterbatch includes the following steps: S1. Weigh the insoluble and infusible conductive polymer and resin according to the mass ratio of the insoluble and infusible conductive polymer in the polymer masterbatch of 10~50% (e.g. 20~40%), premix them using a high-speed mixer with a filling amount of 30~50% and a rotation speed of 200~800 rpm. S2. Use a mixer to melt-mix the mixture from step S1, and extrude it at a temperature of 70~125℃; S3. After cooling and pressing the material from step S2 into tablets, crush it into coarse particles with a particle size of 0.5~2mm to obtain polymer masterbatch.

[0031] The present invention also provides a toner composition for electrostatic developing (for electrophotographic developing equipment), comprising the insoluble and infusible conductive polymer or polymer masterbatch, preferably the insoluble and infusible conductive polymer or polymer masterbatch being used as an internal additive in the toner composition.

[0032] According to an embodiment of the present invention, the colorant composition includes an internal additive, the internal additive comprising the insoluble and infusible conductive polymer or polymer masterbatch.

[0033] According to an embodiment of the present invention, the range of polymer masterbatch dosage is determined according to the following formula: (I) Where, ω cp ω represents the percentage of conductive polymer masterbatch in the total mass of the toner adhesive resin. cp > 0, in units of %; R is a constant; when the binder resin type is polyester, R = 1.17 K·s·cm -3 When the binder resin type of the toner is styrene-acrylic, R = 0.83 K·s·cm -3 ; M i The melt flow index of the colorant without the addition of polymer masterbatch, in cm⁻¹ 3 ·s -1 ; T 1 / 2 The softening point of the toner without the addition of polymer masterbatch, expressed in K. M sc This represents the mass fraction of insoluble and infusible conductive polymer in the polymer masterbatch, expressed in units of 1.

[0034] According to an embodiment of the present invention, the internal additive may further include, but is not limited to, one or more of the following: adhesive resin, colorant, release agent, charge control agent, and magnetic powder; For example, the adhesive resin is selected from one or two of polyester resin, styrene-acrylic resin, etc. For example, the release agent is selected from one or more of paraffin wax, carnauba wax, polyol ester wax, Fischer-Tropsch wax, polypropylene wax, etc.

[0035] According to an embodiment of the present invention, the colorant composition further includes external additives, the types of which may include, but are not limited to, one or more of silica, metal oxides, metal stearate salts, titanates and carbonates of different forms and particle sizes.

[0036] In addition, the dosage of each material in the internal and external additives can be adjusted according to the required developing environment, and only one type of each material can be used, or a mixture of multiple models and specifications of products can be used.

[0037] For example, the mass ratio of the adhesive resin, colorant, charge control agent and release agent is 100:(1~10):(0.5~15):(1~10), preferably 100:(1~10):(0.5~10):(1~6).

[0038] According to an embodiment of the present invention, the weight ratio of the internal additive to the external additive is 100:(0.5~5), preferably 100:(1~3).

[0039] According to an embodiment of the present invention, the internal additive is a molten powder, for example, with a particle size D. V 50 = 5~15μm molten powder.

[0040] The present invention also provides a method for preparing the above-mentioned colorant composition, comprising the following steps: The internal additives are mixed, and then melt-extruded, cooled, tableted, crushed, and graded to obtain a particle size D. V A toner powder with a particle size of 5~15μm (i.e., the above-mentioned molten powder); the toner powder is mixed with external additives to obtain the toner composition.

[0041] The beneficial effects of this invention are as follows: (1) Adding conductive polymers to the internal additives of the toner can effectively solve the problem of poor thermal offset resistance of the toner; (2) By electrochemically doping the conductive polymer, the conductivity of the conductive polymer can be effectively improved, thereby improving the charging performance of the toner. Specifically, the charging concentration of the toner is increased. (3) By preparing the conductive polymer into a polymer masterbatch in advance, the dispersibility of the conductive polymer in the toner resin can be effectively improved, and the thermal offset resistance of the toner can be further improved. (4) Through the accumulation of a large amount of data, the inventors have established a complete strategy for adding conductive polymer masterbatch, which can design the dosage based on the thermal properties of different toners. Attached Figure Description

[0042] Figure 1 and Figure 2The images are SEM images of the insoluble and infusible conductive polypyrrole obtained before and after electrochemical doping in Example 1 of the present invention (before breakage). Detailed Implementation

[0043] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0044] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0045] Examples 1-1 to 1-5 of the preparation of conductive polymer masterbatches are as follows. The resin used in the preparation of each conductive polymer masterbatch is the same as the resin in the corresponding toner composition.

[0046] Example 1-1 Electrochemical doping of conductive polymers 100g of polypyrrole particles were weighed and dispersed in 500 mL of deionized water. 0.5% (based on the mass of the polypyrrole particles) of sodium dodecylbenzenesulfonate was added, and the mixture was stirred at 500 rpm for 5 min to obtain a conductive polymer dispersion. The conductive polymer dispersion was then ultrasonically dispersed at a power of 200 W for 20 min. The conductive polymer dispersion obtained in the above steps was filtered through a 0.45 μm microporous membrane to obtain a conductive polymer film. The conductive polymer film was used as the working electrode, with a platinum mesh as the counter electrode. The electrolyte was an aqueous solution containing 1.0 mol / L p-toluenesulfonic acid. Electrochemical doping was performed using a potentiostat, with the anolyte current set to positive and the current density to 0.8 mA cm⁻¹. 2 The doping time was 90 s. The doped conductive polymer film was then removed from the working electrode and vacuum dried at 50°C for 24 h. The dried conductive polymer film was then pulverized using a grinder at 1500 rpm for 60 min to obtain electrochemically doped polypyrrole powder. The conductivity of the electrochemically doped polypyrrole powder was measured to be 350 ± 15 S cm⁻¹. -1 .

[0047] Preparation of conductive polymer masterbatch Weigh 100g of electrochemically doped polypyrrole powder and mix it with 900g of polyester resin. Then, premix the mixture using a high-speed mixer with a filling amount of 30% and a rotation speed of 800rpm. Use a twin-screw extruder to melt mix the mixture at an extrusion temperature of 70℃. After cooling and pressing the output into tablets, crush it into coarse particles with a particle size of 0.5 mm to obtain conductive polymer masterbatch A.

[0048] Examples 1-2 Electrochemical doping of conductive polymers 100g of polyaniline particles were weighed and dispersed in 500 mL of deionized water. 2.5% (based on the mass of the polyaniline particles) of polyoxyethylene lauryl ether carboxylic acid was added, and the mixture was stirred at 400 rpm for 15 min to obtain a conductive polymer dispersion. The conductive polymer dispersion was then ultrasonically dispersed at a power of 400 W for 10 min. The conductive polymer dispersion obtained in the above steps was filtered through a 0.45 μm microporous membrane to obtain a conductive polymer film. The conductive polymer film was used as the working electrode, with a platinum mesh as the counter electrode. The electrolyte was an aqueous solution containing 1.5 mol / L sulfuric acid. Electrochemical doping was performed using a potentiostat, with the anolyte current set to positive and the current density to 0.5 mA cm⁻¹. -2 The doping time was 120 s. The doped conductive polymer film was then removed from the working electrode and vacuum dried at 50°C for 24 h. The dried conductive polymer film was then pulverized using a grinder at 2000 rpm for 50 min to obtain electrochemically doped polyaniline powder. The conductivity of the electrochemically doped polyaniline powder was measured to be 150 ± 5 S cm⁻¹. -1 .

[0049] Preparation of conductive polymer masterbatch Weigh 200g of electrochemically doped polyaniline powder and mix it with 800g of styrene-acrylic resin. Then, premix the mixture using a high-speed mixer with a filling amount of 50% and a rotation speed of 500rpm. Use a twin-screw extruder to melt mix the mixture at an extrusion temperature of 125℃. After cooling and pressing the output into sheets, crush it into coarse particles with a particle size of 2.0 mm to obtain conductive polymer masterbatch B.

[0050] Examples 1-3 Electrochemical doping of conductive polymers 100g of polythiophene particles were weighed and dispersed in 500 mL of deionized water. 5.0% (based on the mass of the polythiophene particles) of sodium alkyl allyl succinate sulfonate was added, and the mixture was stirred at 300 rpm for 30 min to obtain a conductive polymer dispersion. The conductive polymer dispersion was then ultrasonically dispersed at a power of 300 W for 15 min. The conductive polymer dispersion obtained in the above steps was filtered through a 0.45 μm microporous membrane to obtain a conductive polymer film. The conductive polymer film was used as the working electrode, with a platinum mesh as the counter electrode. The electrolyte was an aqueous solution containing 0.1 mol / L lithium perchlorate. Electrochemical doping was performed using a potentiostat, with the anolyte current set to positive and the current density to 1.0 mA cm⁻¹. -2 The doping time was 60 s. The doped conductive polymer film was then removed from the working electrode and vacuum dried at 50°C for 24 h. The dried conductive polymer film was then pulverized using a grinder at 2500 rpm for 40 min to obtain electrochemically doped polythiophene powder. The conductivity of the electrochemically doped polythiophene powder was measured to be 280 ± 12 S cm⁻¹. -1 .

[0051] Preparation of conductive polymer masterbatch Weigh 300g of electrochemically doped polythiophene powder and mix it with 700g of polyester resin. Then, premix the mixture using a high-speed mixer with a filling amount of 40% and a rotation speed of 400rpm. Use an open roller kneader to melt-mix the mixture at a kneading temperature of 95℃. After cooling and pressing the output into tablets, crush it into coarse particles with a particle size of 1.5 mm to obtain conductive polymer masterbatch C.

[0052] Examples 1-4 Electrochemical doping of conductive polymers 100g of poly(3,4-ethylenedioxythiophene) particles were weighed and dispersed in 500 mL of deionized water. 1.5% (based on the mass of the poly(3,4-ethylenedioxythiophene) particles) of sodium dodecyl sulfate was added, and the mixture was stirred at 350 rpm for 25 min to obtain a conductive polymer dispersion. The conductive polymer dispersion was then ultrasonically dispersed at a power of 600 W for 5 min. The conductive polymer dispersion obtained in the above steps was filtered through a 0.45 μm microporous membrane to obtain a conductive polymer film. The conductive polymer film was used as the working electrode, with a platinum mesh as the counter electrode. The electrolyte was an aqueous solution containing 2.0 mol / L sodium styrene sulfonate. Electrochemical doping was performed using a potentiostat, with the anolyte current set to positive and the current density to 1.5 mA cm⁻¹. -2The doping time was 10 s. The doped conductive polymer film was then removed from the working electrode and vacuum dried at 50°C for 24 h. The dried conductive polymer film was then pulverized using a grinder at 1800 rpm for 30 min to obtain electrochemically doped poly(3,4-ethylenedioxythiophene) powder. The conductivity of the electrochemically doped poly(3,4-ethylenedioxythiophene) powder was measured to be 190 ± 7 S cm⁻¹. -1 .

[0053] Preparation of conductive polymer masterbatch Weigh 400g of electrochemically doped poly(3,4-ethylenedioxythiophene) powder and mix it with 600g of styrene-acrylic resin. Then, premix the mixture using a high-speed mixer with a filling amount of 35% and a rotation speed of 600rpm. Use a twin-screw extruder to melt mix the mixture at an extrusion temperature of 110℃. After cooling and pressing the output into tablets, crush it into coarse particles with a particle size of 2.0 mm to obtain conductive polymer masterbatch D.

[0054] Examples 1-5 Electrochemical doping of conductive polymers 100g of polycarbazole particles were weighed and dispersed in 500 mL of deionized water. 4.0% (based on the mass of the polycarbazole particles) of phenolic ether phosphate was added, and the mixture was stirred at 450 rpm for 20 min to obtain a conductive polymer dispersion. The conductive polymer dispersion was then ultrasonically dispersed at a power of 500 W for 8 min. The conductive polymer dispersion obtained in the above steps was filtered through a 0.45 μm microporous membrane to obtain a conductive polymer film. The conductive polymer film was used as the working electrode, with a platinum mesh as the counter electrode. The electrolyte was an aqueous solution containing 0.5 mol / L tetrabutylammonium hexafluorophosphate. Electrochemical doping was performed using a potentiostat, with the anolyte current set to positive and the current density to 0.9 mA·cm⁻¹. -2 The doping time was 100 s. The doped conductive polymer film was then removed from the working electrode and vacuum dried at 50°C for 24 h. The dried conductive polymer film was then pulverized using a grinder at 3500 rpm for 20 min to obtain electrochemically doped polycarbazole powder. The conductivity of the electrochemically doped polycarbazole powder was measured to be 250 ± 10 S cm⁻¹. -1 .

[0055] Preparation of conductive polymer masterbatch Weigh 500g of electrochemically doped polybenzazole powder and mix it with 500g of polyester resin. Then, premix the mixture using a high-speed mixer with a filling amount of 45% and a rotation speed of 200rpm. Use an open roller kneader to melt-mix the mixture at a kneading temperature of 85℃. After cooling and pressing the output into tablets, crush it into coarse particles with a particle size of 1.0 mm to obtain conductive polymer masterbatch E.

[0056] Examples 2-1 to 2-5 of the preparation of colorants are as follows, where the parts are parts by mass.

[0057] All materials are calculated based on 100 parts by weight of the binding resin. The actual amount of conductive polymer added in the examples was first determined by experimentally testing the softening point and melt index of the toner prepared under the same formulation and process conditions without the conductive polymer; secondly, the median amount added was calculated according to formula (1) (median = ...). Finally, based on the median addition amount, further experiments were conducted to verify and adjust the results, as detailed in Table 1.

[0058] (I) in, ω cp This represents the percentage of conductive polymer masterbatch in the total mass of the colorant adhesive resin. ω cp > 0, in units of %; R is a constant, when the binder resin used for the toner is polyester type, R = 1.17 K·s·cm -3 When the colorant uses a styrene-acrylic adhesive resin, R = 0.83 K·s·cm -3 ; M i The melt flow index of the toner when no conductive polymer masterbatch is used, in cm⁻¹. 3 ·s -1 ; T 1 / 2 The softening point of the toner when no conductive polymer masterbatch is used, in K; M sc This represents the mass fraction of conductive polymer in the conductive polymer masterbatch, expressed in units of 1.

[0059] Table 1. Amount ω of conductive polymer added in the examples cp Thermal properties of toners (T) 1 / 2 M i The relationship between ) Example Resin type Resin type T1 / 2 (℃) Mi (cm3·s-1) Conductive polymer masterbatch Median ωcp dosage (per serving) Optimal dosage of ωcp (per serving) R Msc 2-1 Polyester NH-3308 105 0.485 A 18.9 18.0 1.17 0.1 2-2 Phenylene XPA8106 135 0.226 B 3.7 5.6 0.83 0.2 2-3 Polyester PI7050 117 0.489 C 6.8 9.3 1.17 0.3 2-4 Phenylene XPA8063 125 0.165 D 1.3 2.5 0.83 0.4 2-5 Polyester HH0710 112 0.782 E 6.3 6.0 1.17 0.5 Example 2-1 100 parts of polyester resin NH-3308, 5 parts of carbon black Raven 1185 Ultra, 1.5 parts of charge control agent E84, 3.5 parts of paraffin HNP-9PD, and 18 parts of conductive polymer masterbatch A were mixed and homogenized. The mixture was then subjected to melt extrusion, cooling, tableting, coarse crushing, fine grinding, and grading to obtain a particle size D. V50 A black toner composition for electrostatic development is obtained by adding 1.5 parts of fumed silica R202 to a toner powder with a particle size of 9.5 μm.

[0060] Example 2-2 100 parts of styrene-acrylic resin XPA8106, 6.5 parts of cyan pigment Hostaperm BG, 0.7 parts of charge control agent N28, 3.5 parts of carnauba wax T-1, and 5.6 parts of conductive polymer masterbatch B were mixed and homogenized. The mixture was then subjected to melt extrusion, cooling, tableting, coarse crushing, fine grinding, and grading to obtain a particle size D. V50 A cyan toner composition for electrostatic development is obtained by adding 1.0 part of fumed silica R202 and 0.5 parts of fumed silica H2000T toner powder with a particle size of 8.8 μm.

[0061] Example 2-3 100 parts of polyester resin PI7050, 4.5 parts of pigment red 146, 8 parts of polymeric charge control agent FCA-1001NS, 3.5 parts of polyol ester wax WE-5, and 9.3 parts of conductive polymer masterbatch C were mixed and homogenized. The mixture was then subjected to melt extrusion, cooling, tableting, coarse crushing, fine grinding, and grading to obtain a particle size D. V50 A magenta toner composition for electrostatic development is obtained by adding 1.3 parts of fumed silica R812S to a toner powder with a particle size of 9.0 μm.

[0062] Examples 2-4 100 parts of styrene-acrylic resin XPA8063, 4.0 parts of yellow pigment Novoperm Yellow HG 01-CN09, 1 part of charge control agent N24H, 2.5 parts of Fischer-Tropsch wax FT115, and 2.5 parts of conductive polymer masterbatch D were mixed and homogenized. The mixture was then subjected to melt extrusion, cooling, tableting, coarse crushing, fine grinding, and grading to obtain a particle size D. V50 A yellow toner composition for electrostatic development is obtained by adding 0.5 parts of fumed silica R976S and 1.0 part of TG-7180 ​​to a toner powder with a particle size of 7.8 μm.

[0063] Examples 2-5 100 parts of polyester resin HH0710, 6 parts of carbon black XPB685, 1.5 parts of charge control agent T-77, 3 parts of polypropylene wax HI-WAX NP105, and 6 parts of conductive polymer masterbatch E were mixed and homogenized. The mixture was then subjected to melt extrusion, cooling, tableting, coarse crushing, fine grinding, and grading to obtain a particle size D. V50 A toner powder with a particle size of 10.0 μm is added, along with 0.7 parts of fumed silica TG-811F and 0.5 parts of sol-gel silica TG-C413, to obtain a black toner composition for electrostatic development.

[0064] Comparative examples 3-1 to 3-5 for the preparation of toners are as follows.

[0065] Comparative Example 3-1 Except for the absence of conductive polymer masterbatch A, the preparation process was the same as in Example 2-1, resulting in a black toner for comparison.

[0066] Comparative Example 3-2 Except for the absence of electrochemical doping in Examples 1-2, where conductive polymer B' was prepared using a masterbatch process, the other preparation formulations and processes were the same as in Examples 2-2, resulting in cyan colorants for comparison.

[0067] Preparation of conductive polymer B': Weigh 200g of polyaniline powder and mix it with 800g of styrene-acrylic resin. Then, premix the mixture using a high-speed mixer with a filling amount of 50% and a rotation speed of 500rpm. Use a twin-screw extruder to melt mix the mixture at an extrusion temperature of 125℃. After cooling and pressing the output into sheets, crush it into coarse particles with a particle size of 2.0 mm to obtain conductive polymer masterbatch B'.

[0068] Comparative Example 3-3 Unlike Examples 2-3, the conductive polymer masterbatch C was replaced with a mixture of electrochemically doped polythiophene powder and polyester resin PI7050 from Examples 1-3 at a mass ratio of 3:7 (by simple physical mixing, i.e., low-speed stirring and mixing, without high-temperature kneading) to obtain a magenta colorant for comparison.

[0069] Comparative Examples 3-4 Except for increasing the amount of conductive polymer masterbatch D to 4 parts, the other preparation formulation and process are the same as in Examples 2-4, resulting in a yellow toner for comparison.

[0070] Comparative Examples 3-5 Except for reducing the amount of conductive polymer masterbatch E to 3 parts, the other preparation formulation and process are the same as in Examples 2-5, resulting in a black toner for comparison.

[0071] Comparative Examples 3-6 Unlike Examples 2-2, the conductive polymer masterbatch B was replaced with a mixture of electrochemically doped polyaniline powder and styrene-acrylic resin XPA8106 from Examples 1-2 at a mass ratio of 2:8 (by simple physical mixing, i.e., low-speed stirring, without high-temperature kneading) to obtain a cyan colorant for comparison.

[0072] Test Example 4-1 The application performance (fixing fastness, anti-electrolyte ratio and temperature at which thermal offset occurs) of the toner compositions prepared in Examples 2-1 to 2-5 and Comparative Examples 3-1 to 3-6 are shown in Table 2.

[0073] The fixing fastness test method is as follows: After the fixing module (HP M254 printer) has cooled down sufficiently (without continuous printing tasks), turn on the printer; print a test pattern with a uniform color block from the computer; measure the initial density D1; then use 3M tape to stick the color block, press it with a 200g weight for 3 seconds, and then slowly peel it off at a uniform speed; after removing the tape, measure the density D2 again; the ratio of (D2 / D1) × 100% is the fixing fastness.

[0074] The method for testing the proportion of anti-electrostatic toner is as follows: Using an HP M254 printer, load 30g of toner composition, print 100 pages of a 5% consumable version at room temperature, remove the drum, and use a q / m-meter charge meter with Airflow=160. Move the moving head to evenly pick up toner from 5 areas on the developing roller. After the equipment stops automatically, remove the slide from the moving head and place it into the test chamber according to the marked charge. Click "Scan" to start the measurement. After the scan is completed, click the "Results" menu and check "q / dDistribution" to obtain the test results of the anti-electrostatic toner mass ratio.

[0075] The method for measuring temperature when thermal offset occurs is as follows: Thermal offset performance is evaluated using a silicone-free fuser unit (hot roller + pressure roller), where the hot roller diameter is 3cm, the pressure opening width is 0.4cm, and the pressure opening pressure is 2kg / cm. The temperature is set to 70g / m² using software. 2 The electrostatic copy paper passes through the fixing unit at a linear speed of 25 cm / s; the hot roller temperatures are set to 180℃, 190℃, 200℃, 210℃, 220℃, 230℃, 240℃, 250℃, and 260℃ respectively. The highest temperature at which thermal offset is observed (i.e., the appearance of a ghost image on the manuscript surface with a hot roller cycle of 9.4cm) is the temperature at which thermal offset occurs.

[0076] Table 2. Evaluation results of application performance of the toner preparation examples and comparative examples Example Fixing fastness / % Reactive powder ratio / % Temperature at which thermal offset occurs / °C Comparative example Fixing fastness / % Reactive powder ratio / % Temperature at which thermal offset occurs / °C 2-1 95.5 7.9 220 3-1 96.7 15.7 180 2-2 97.1 11.2 240 3-2 96.5 22.3 240 3-6 95.7 18.9 210 2-3 98.3 9.6 220 3-3 97.9 13.9 210 2-4 96.6 7.3 230 3-4 88.9 6.6 230 2-5 97.7 10.4 220 3-5 98.9 9.9 200 As can be seen from the test results in Table 2, the toner composition containing insoluble and infusible conductive polymer prepared according to Example 2-x (x=1-5) has high fixing fastness, low proportion of reactive powder and high resistance to thermal offset temperature.

[0077] In Comparative Example 3-1, the toner obtained without the addition of conductive polymer masterbatch A completely lacked resistance to thermal migration, exhibiting thermal migration issues at an initial temperature of 180°C, rendering it unusable. However, in Example 2-1, the addition of conductive polymer masterbatch A significantly enhanced the toner's resistance to thermal migration, raising the temperature at which thermal migration occurred to 220°C. Furthermore, the addition of conductive polymer masterbatch A produced an unexpected technical effect: the proportion of reactive toner decreased from 15.7% to 7.9%. This lower proportion of reactive toner helps improve the concentration of charged distribution in the toner, thereby improving print quality and reducing waste toner.

[0078] To further illustrate the effect of adding the insoluble and infusible conductive polymer on the proportion of anti-reactive powder, we conducted comparative examples 3-2 and 3-6. First, in Comparative Example 3-2, the conductive polymer was not electrochemically doped. In this case, the conductivity of the conductive polymer was low, and the proportion of anti-reactive powder in the toner increased significantly from 11.2% after electrochemical doping to 22.3% without doping, an increase of 99.1%. Second, in Comparative Example 3-6, the conductive polymer was added directly without being prepared as a masterbatch. In this case, the proportion of anti-reactive powder increased from 11.2% in Example 2-2 to 18.9%, an increase of 68.8%. These results show that the conductivity of the conductive polymer is the main reason for reducing the proportion of anti-reactive powder. However, preparing it as a masterbatch improves the uniformity of the conductive polymer's dispersion within the toner, thus also contributing to a reduction in the proportion of anti-reactive powder. The combination of these two factors yielded an unexpected technical effect: a significant reduction in the proportion of anti-reactive powder in the toner composition, thereby improving print quality.

[0079] The amount of insoluble and infusible conductive polymer has a significant impact on the thermal drift resistance of toners, and its application cannot be determined through limited and simple experiments. After extensive experimentation, reasoning, and summarization, the applicant derived the dosage adjustment formula (I). In Comparative Examples 3-4 and 3-5, the amount of conductive polymer was outside the range specified in Formula (I). In Comparative Example 3-4, the amount of conductive polymer exceeded the upper limit of the specified value (3.8 parts), resulting in a significant decrease in the fixing fastness of the toner. In Comparative Example 3-5, the amount of conductive polymer was below the lower limit of the specified value (3.8 parts), resulting in a significant decrease in the thermal drift resistance of the toner.

[0080] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. Application of insoluble and infusible conductive polymers or polymer masterbatches in the preparation of toner compositions.

2. The application according to claim 1, characterized in that, The insoluble and infusible conductive polymer is an electrochemically doped conductive polymer; The dopant used in electrochemical doping is a p-type dopant, including but not limited to one or more selected from hydrofluoric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, boron trifluoride, boron trichloride, sulfuric acid, nitric acid, lithium perchlorate, sodium perchlorate, p-toluenesulfonic acid, sodium p-toluenesulfonate, sodium dodecylbenzenesulfonate, sodium polystyrene sulfonate, sodium nitrite, copper sulfate, copper nitrate, sodium tetrafluoroborate, sodium tetrabutylphosphine tetrafluoroborate, sodium tetrabutylhexafluorophosphate, sodium tetrabutylhexafluorophosphate, ammonium tetrabutylhexafluorophosphate, sodium hexafluorophosphate, boron trifluoride ether, styrene sulfonic acid, polystyrene sulfonic acid, and carboxylated carbon nanotubes; The conductive polymer is selected from one or more of polypyrrole and its derivatives, polyaniline and its derivatives, polythiophene and its derivatives, and polycarbazole and its derivatives.

3. The application according to claim 1, characterized in that, The conductivity σ of the insoluble and infusible conductive polymer is ≥100 S / cm. -1 For example, 100 S cm -1 ≤σ≤400 S cm -1 .

4. The application according to claim 1, characterized in that, The toner is a toner used for electrostatic development.

5. The application according to claim 1, characterized in that, The preparation method of the insoluble and infusible conductive polymer includes the following steps: (1) A conductive polymer, anionic surfactant and water are mixed to form a conductive polymer dispersion; (2) The conductive polymer dispersion is subjected to ultrasonic treatment; (3) After step (2) is completed, a conductive polymer film is prepared; (4) The conductive polymer film is prepared as the working electrode, a platinum mesh is used as the counter electrode, and the electrolyte is... p Electrochemical doping was performed using an aqueous solution of a type of dopant and a potentiostat. (5) After step (4) is completed, remove the conductive polymer film from the working electrode and dry it; (6) The dried conductive polymer film is crushed.

6. A toner composition for electrostatic development, comprising the insoluble and infusible conductive polymer or polymer masterbatch as described in any one of claims 1 to 5, preferably the internal additives of the toner composition comprising the insoluble and infusible conductive polymer or polymer masterbatch; The polymer masterbatch is obtained by melting the insoluble and infusible conductive polymer and resin.

7. The toner composition according to claim 6, characterized in that, In the polymer masterbatch, the mass ratio of the insoluble and infusible conductive polymer to the resin is 10~50:50~90; And / or, the resin is a polyester resin or a styrene-acrylic resin.

8. The toner composition according to claim 6, characterized in that, The method for preparing the polymer masterbatch includes the following steps: S1. Mix the insoluble and infusible conductive polymer and resin; S2. The mixture obtained in step S1 is melt-extruded; S3. After the material discharged from step S2 is cooled and pressed into tablets, it is crushed to obtain the polymer masterbatch.

9. The toner composition according to claim 6, characterized in that, The range of polymer masterbatch dosage is determined according to the following formula: （Ⅰ） Where, ω cp ω represents the percentage of conductive polymer masterbatch in the total mass of the toner adhesive resin. cp >0, in units of %; R is a constant; when the binder resin type is polyester, R = 1.17 K·s·cm -3 When the binder resin type of the toner is styrene-acrylic, R = 0.83 K·s·cm -3 ; M i The melt flow index of the colorant without the addition of polymer masterbatch, in cm⁻¹ 3 ·s -1 ; T 1 / 2 The softening point of the toner without the addition of polymer masterbatch, expressed in K. M sc This represents the mass fraction of insoluble and infusible conductive polymer in the polymer masterbatch, expressed in units of 1.

10. The toner composition according to claim 6, characterized in that, The internal additives also include one or more of the following: adhesive resin, colorant, release agent, charge control agent, and magnetic powder; For example, the adhesive resin is selected from one or both of polyester resin and styrene-acrylic resin; For example, the release agent is selected from one or more of paraffin wax, carnauba wax, polyol ester wax, Fischer-Tropsch wax, and polypropylene wax; And / or, the colorant composition further includes external additives, which include one or more of silica, metal oxides, metal stearate, titanate and carbonate.

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