JPH0422512B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for producing a binding resin, and more particularly to a method for producing a binding resin, and more specifically, a method for producing a binder resin, and more particularly, a method for producing a binding resin, and more specifically, a method for producing a binding resin, and more specifically, a method for producing a binding resin, and more particularly, a method for producing a binding resin, and more specifically, a method for producing a binding resin, and more specifically, a method for producing a binding resin, and more particularly, a method for producing a binding resin, and more particularly, a method for producing a binding resin, and more specifically, a method for producing a binding resin, and more specifically, a method for producing a binding resin, and more specifically, a method for producing a binding resin. The present invention relates to a method for producing a binding resin. [Prior art and problems] As a conventional electrophotographic method, US Patent No. 2297691
As stated in the specification of No. 2357809, etc.
A photoconductive insulating layer is uniformly charged, the layer is then exposed to light, and the charge on the exposed portions is dissipated to form an electrical latent image, and the latent image is injected with toner. After the visible image is transferred to a transfer material such as transfer paper (transfer process), heat and pressure are applied. Alternatively, it consists of a step of permanently fixing (fixing step) by another suitable fixing method. As described above, the toner must have the functions required not only in the development process but also in each of the transfer and fixing processes. Generally, toner is subjected to mechanical frictional force due to shearing force and impact force during mechanical operation in a developing device, and deteriorates while copying several thousand to tens of thousands of sheets.
To prevent such toner deterioration, it is best to use a strong resin with a large molecular weight that can withstand mechanical friction, but these resins generally have a high softening point and cannot be used in oven fixing, which is a non-contact fixing method, or infrared rays. With radiant fixing, the thermal efficiency is poor, so fixing is not sufficient.Also, with the contact fixing method, which has good thermal efficiency, even in the widely used heat roller fixing method, the temperature of the heat roller has to be adjusted to ensure sufficient fixing. It becomes necessary to increase the
Not only does this cause problems such as curling of the paper and increased energy consumption, but also the use of such a resin causes a significant drop in production efficiency when producing toner by pulverizing it. Therefore, it is not possible to use a binder resin (binding resin) whose polymerization degree and even softening point are too high. On the other hand, in the heat roller fixing method, the heating roller surface and the toner image surface of the sheet to be fixed are in pressure contact, so the thermal efficiency is extremely high and it is widely used from low speeds to high speeds. When doing so, a so-called offset phenomenon is likely to occur, in which toner adheres to the surface of the heating roller and is transferred to subsequent transfer paper or the like. To prevent this phenomenon, the surface of the heating roller is treated with a material with excellent mold release properties such as fluorine-based resin, and in addition, a mold release agent such as silicone oil is applied to the surface of the heating roller to completely prevent the offset phenomenon. are doing. However, the method of applying silicone oil or the like is not preferable because it not only increases the size of the fixing device and increases the cost, but also makes it complicated, which can easily cause trouble. Also, as described in Japanese Patent Publication No. 55-6895 and Japanese Patent Application Laid-open No. 56-98202, there is a method to improve offset development by widening the molecular weight distribution width of the binder resin, but the degree of polymerization of the resin increases and fixation becomes difficult. The temperature also needs to be high. As a further improved method, Special Publication No. 57-493,
As described in JP-A-50-44836 and JP-A-57-37353, there is a method of improving the offset phenomenon by making the resin asymmetrical and crosslinking, but the fixing point has not been improved. Generally, the minimum fusing temperature is between cold offset and hot offset, so the usable temperature range is
It is between the minimum fixing temperature and hot offset, and by lowering the minimum fixing temperature as much as possible and raising the minimum hot offset temperature as much as possible, it is possible to lower the usable fixing temperature and expand the usable temperature range, which saves energy. , high-speed fixing, and prevents paper from curling. In addition, since double-sided copying can be performed without trouble, copying machines have become more intelligent, and the temperature control of the fixing device has become more accurate.
There are many advantages such as relaxing the tolerance range. Therefore, resins and toners with good fixing properties and offset resistance are always desired. In addition, when using a styrene-based binder resin to achieve such requirements, Japanese Patent Application Laid-Open No. 49-65232,
As described in JP-A-50-28840 and JP-A-50-81342, methods of adding paraffin wax, low molecular weight polyolefin, etc. as offset preventive agents are known, but they are not effective if the amount added is small. It has been confirmed that if the amount is too large, the developer deteriorates quickly, and in the case of polyester resin, even if the offset preventive agent mentioned above is applied, it has little effect, and if the amount used is too large, the developer deteriorates quickly. Polyester resin inherently has good fixing properties, and as described in U.S. Pat. No. 3,590,000, it can be fixed sufficiently even in a non-contact fixing method, but it is prone to offset phenomenon and cannot be used in a heat roller fixing method. was difficult. As described in JP-A-50-44836, JP-A-57-37353, and JP-A-57-109875, polyester resins with improved offset resistance using polyhydric carboxylic acids have sufficient properties for use. Those that do not have offset resistance, or those that do, not only sacrifice the low-temperature fixing properties inherent to polyester resins, but also have extremely poor crushability in the toner forming process, making it difficult to develop. There were also problems with drug production. Generally, a toner is composed of a binder resin, a colorant, and other additives, with the binder resin being the main component. As toner binder resins, coumaron indene resins, terpene resins, styrene resins or their copolymer resins, polyester resins, epoxy resins, etc. are generally used, but there are few binder resins that are strongly positively triboelectrified. A commonly known method for making toner positive is to add additives such as nigrosine dye as a charge control agent, but this method has poor compatibility with the binder resin that constitutes the main component of toner, and the If they are mixed for a long time in the developing device, the particles will be destroyed, and if nigrosine etc. is simply dispersed, particles of opposite (negative) polarity that do not contain nigrosine etc. will be generated, and the area where there is no image signal will be generated. So-called background fog development occurs in which toner also adheres to the surface. Furthermore, when nigrosine dye or the like is used, since it has hydrophilic properties, the amount of charge changes depending on the humidity of the environment, resulting in a decrease in image quality. In addition, nigrosine dyes generally have strong coloring and have disadvantages such as being incompatible with color toners. In view of the above, it is desired to develop toner binder resins and toners that are strongly positively charged, unaffected by environmental humidity, and have excellent durability. The present invention was made to meet these demands, and its purpose is to provide a developer that can prevent offset without applying an anti-offset liquid in a heat roller fixing system and that can be fixed at a lower fixing temperature. The purpose is to provide a binding resin. Another object of the present invention is to provide a binder resin for a developer which can prevent offset without adding an offset preventive agent in a heat roller fixing system and which can be fixed at a lower fixing temperature. Another object of the present invention is to provide a binder resin for a developer that has good fluidity, does not cause blocking, and has a long life (hard to deteriorate). Another object of the present invention is to improve kneading properties during developer production.
An object of the present invention is to provide a binder resin for a developer with good pulverizability. Another object of the present invention is to provide a toner that forms clear and fog-free images using a toner binder resin that is inherently strongly positively charged in a dry developer for electrophotography. More specifically, it is an object of the present invention to provide a toner in which the above-mentioned drawbacks are improved, the influence of environmental humidity is extremely small, the binder resin has essentially positive triboelectric chargeability, and the binder resin has excellent durability. Another object of the present invention is to provide a clear color developer with good transparency. [Means for Solving the Problems] In order to achieve the above-mentioned object, the present inventors conducted extensive research and arrived at the present invention. That is, the present invention provides (c) when producing a vinyl polymer from (a) styrene and/or styrene derivatives and (b) one or more monomers selected from methacrylic acid, acrylic acid, and esters thereof. The present invention relates to a method for producing a binding resin characterized by reacting a dihydric or higher alcohol having a tertiary amino group and/or an epoxy compound having a tertiary amino group. In the present invention, considering the use of the binding resin,
Preferably, the component (c) above is a dihydric or higher alcohol having a tertiary amino group represented by the following general formulas [] to [], and the amount used is 0.05 to 0.05 to the total amount of monomers. 50% by weight, and the number of moles used does not exceed the number of moles of component (B). (In formulas [] to [], R ₁ , R ₂ , R ₅ , R ₆ ,
R ₇ , R ₈ , ₉ , R ₁₀ , R ₁₁ , R ₁₂ , R ₁₃ , R ₁₄ , R ₁₆ are alkylene groups having 1 to 15 carbon atoms, and R ₃ and R ₄ are alkyl groups having 1 to 10 carbon atoms. The groups R ₁₇ and R ₁₈ represent an alkyl group having 1 to 4 carbon atoms, and R ₁₇ and R ₁₈ may form a heterocyclic ring of the same nitrogen atom. R ₁₅ is an alkyl group having 1 to 3 carbon atoms or

〔Example〕

Examples of the invention will be described below, but the invention is not limited to these examples. It should be noted that all composition ratios shown in Examples are expressed in parts by weight. Example 1 Xylene was placed in a reactor equipped with a stirrer, a nitrogen inlet tube, a thermometer, a reflux condenser tube, and a dropping funnel.
500 parts of N,N'-bis(2-hydroxypropyl)piperazine and 2 parts of dibutyltin oxide were charged, and the temperature was adjusted to 80°C. A mixed solution of 820 parts of styrene, 130 parts of n-butyl acrylate and 10 parts of α-α'-azobisisobutyronitrile was dropwise polymerized over 4 hours under a nitrogen stream. After aging at the same temperature for 10 hours after the dropwise addition, the temperature was gradually raised to 210°C while the pressure was reduced to 2 mmHg, and the xylene was distilled off.
The molten resin was taken out into a stainless steel vat, left to cool, and pulverized to obtain a powdered resin (softening point of Koka flow tester: 126.0°C, Tg: 62.0°C).
This softening point was determined by heating a 1 cm ³ sample at a heating rate of 6°C/min using a Koka type flow tester (manufactured by Shimadzu Corporation) and applying a load of 20 kg/cm ² with a plunger. A 1 mm nozzle is extruded, thereby drawing a plunger drop-temperature curve of the flow tester, and when the height of the S-shaped curve is h, the temperature corresponding to h/2 is taken as the softening point. . After mixing 93 parts of the resin and 7 parts of carbon black (Regal 400R manufactured by Kabot Corporation) in a ball mill,
After coarsely pulverizing with a hammer mill, finely pulverizing with a jet mill, and classifying, a toner having an average particle size of 13.5 μm was obtained.
The obtained toner was mixed with carrier iron powder (manufactured by Nippon Tetsuko Co., Ltd.; EFV200/300), and the amount of charge was measured with a blow-off measuring device, and it was found to be +19 μc/g. A developer was prepared by mixing 91 g of the toner with 1209 g of carrier iron powder, and a commercially available electrophotographic copying machine (the photoconductor is an organic photoconductor, the fixing roller has a diameter of 60 mm, the rotation speed is 255 mm/sec, and the fixing device is When the image was produced using a heat roller with variable temperature and the oil application device removed, a clear image was obtained without background smudges, smearing, or missing solid black areas. When the fixing temperature was controlled between 140℃ and 220℃ and the image fixation and offset properties were evaluated, the result was 150℃.
It was sufficiently fixed at ℃, and no hot offset occurred. When images were printed up to 50,000 sheets, clear images were obtained with no background fog or missing solid black areas. The minimum fixing temperature here is 15mm x 7.5mm on the bottom.
A load of 500g was placed on a sand eraser, and the image fixed through the fixing machine was rubbed back and forth 5 times, and the optical reflection density was measured using a Macbeth reflection densitometer before and after rubbing, and the fixing rate was determined by the following definition. This refers to the temperature of the fixing roller when it exceeds 70%. Fixing rate=image density after rubbing/image density before rubbing Example 2 500 parts of xylene and 20 parts of triethanolamine were charged into the reactor of Example 1, and the temperature was adjusted to 80°C. 790 parts of α-methylstyrene under nitrogen stream,
10 parts of acrylic acid, 2-ethylhexyl acrylate
A mixture of 180 parts of α,α'-azobisdimethylvaleronitrile and 20 parts of α,α′-azobisdimethylvaleronitrile was dropwise polymerized over 4 hours.
After aging at the same temperature for 10 hours after the dropwise addition, the temperature was gradually raised to 210°C while the pressure was reduced to 2 mmHg, the xylene was distilled off, and the molten resin was taken out into a stainless steel vat, left to cool, and pulverized to form a powder. resin (Koka type flow tester softening point 124.5℃,
Tg65.0℃) was obtained. After mixing 93 parts of the resin and 7 parts of carbon black (Regal 400R manufactured by Kabot Corporation) in a ball mill,
The mixture was kneaded, crushed, and classified to obtain a toner with an average particle size of 13.2μ. The amount of charge of the obtained toner was +15 μc/g. A developer was prepared by mixing 91 g of the toner with 1209 g of carrier iron powder, and an image was produced using the same evaluation machine as in Example 1. A clear image was obtained without background smudges, bleeding, or missing solid black areas. It was done. When the fixing temperature of the fixing device was controlled and the image fixability and offset properties were evaluated, the image was fixed at 148° C. and no hot offset occurred. When images were printed up to 50,000 sheets, clear images were obtained with no background fog or missing solid black areas. Example 3 In the reactor of Example 1, 500 parts of xylene, N,N'-
15 parts of dimethyl-N,N'-bis(2-hydroxyethyl)ethylenediamine, 840 parts of styrene, 10 parts of methacrylic acid, 135 parts of butyl acrylate, and α,
Using 10 parts of α′-azobisdimethylvaleronitrile, a powdered resin (softening point 123.0°C, Tg 63.2°C using Koka flow tester) was prepared in the same manner as in Example 1.
I got it. After mixing 93 parts of the resin and 7 parts of carbon black (Regal 400R manufactured by Kabot Corporation) in a ball mill,
The mixture was kneaded, crushed, and classified to obtain a toner with an average particle size of 13.0μ. The charge amount of the obtained toner was +14 μc/g. Mix 91g of the toner with 1209g of carrier iron powder,
When a developer was prepared and an image was produced using the same evaluation machine as in Example 1, a clear image was obtained without background smear, bleeding, or missing solid black areas. When the fixing temperature of the fixing device was controlled and the image fixing and offset properties were evaluated, the image was fixed at 145°C.
No hot offset occurred. When images were printed up to 50,000 sheets, clear images were obtained with no background fog or missing solid black areas. Example 4 In the reactor of Example 1, 500 parts of xylene, 2-methyl-2-N,N-dimethylaminomethyl-1,3
- Propanediol part, 855 parts of styrene, 10 parts of methacrylic acid, 120 parts of lauryl methacrylate and α,
Using 10 parts of α'-azobisdimethylvaleronitrile, a powdered resin (Koka flow tester softening point 123.6°C, Tg 62.3) was prepared in the same manner as in Example 1.
°C) was obtained. After mixing 93 parts of the resin and 7 parts of carbon black (Regal 400R manufactured by Kabot Corporation) in a ball mill,
The mixture was kneaded, crushed, and classified to obtain a toner with an average particle size of 13.2μ. The charge amount of the obtained toner was +16 μc/g. Mix 91g of the toner with 1209g of carrier iron powder,
When a developer was prepared and an image was produced using the same evaluation machine as in Example 1, a clear image was obtained without background smear, bleeding, or missing solid black areas. When the fixing temperature of the fixing device was controlled and the image fixation and offset properties were evaluated, the image was fixed at 144℃.
No hot offset occurred. When images were printed up to 50,000 sheets, clear images were obtained with no background fog or missing solid black areas. Example 5 In the reactor of Example 1, 500 parts of xylene, 13 parts of the following epoxy compound, A powdered resin (Koka formula flow tester softening point
125.4℃, Tg65.2℃). After mixing 93 parts of the resin and 7 parts of carbon black (Regal 400R manufactured by Kabot Corporation) in a ball mill,
The mixture was kneaded, crushed, and classified to obtain a toner with an average particle size of 13.7μ. The charge amount of the obtained toner was +16 μc/g. Mix 91g of the toner with 1209g of carrier iron powder,
When a developer was prepared and an image was produced using the same evaluation machine as in Example 1, a clear image was obtained without background smear, bleeding, or missing solid black areas. When the fixing temperature of the fixing device was controlled and the image fixing and offset properties were evaluated, the image was fixed at 146°C.
No hot offset occurred. When images were printed up to 50,000 sheets, clear images were obtained with no background fog or missing solid black areas. Comparative Example 1 Resin (Koka flow tester softening point
128.4℃, Tg66.0℃). After mixing 93 parts of the resin and 7 parts of carbon black (Regal 400R manufactured by Kabot Corporation) in a ball mill,
The mixture was kneaded, crushed, and classified to obtain a toner with an average particle size of 13.0μ. When the obtained toner was mixed with carrier iron powder and the amount of charge was measured using a blow-off measuring machine, -
It was 7μc/g.

Claims (1)

[Claims] 1. When producing a vinyl polymer from (a) styrene and/or styrene derivatives and (b) one or more monomers selected from methacrylic acid, acrylic acid, and esters thereof, ( c) A method for producing a binding resin, which comprises reacting a dihydric or higher alcohol having a tertiary amino group and/or an epoxy compound having a tertiary amino group. 2. The component (c) is a dihydric or higher alcohol having a tertiary amino group represented by the following general formulas [] to [], and the amount used is based on the total amount of monomers.
The manufacturing method according to claim 1, wherein the amount is 0.05 to 50% by weight, and the number of moles used does not exceed the number of moles of component (b). (In formulas [] to [], R ₁ , R ₂ , R ₅ , R ₆ ,
R ₇ , R ₈ , R ₉ , R ₁₀ , R ₁₁ , R ₁₂ , R ₁₃ , R ₁₄ , R ₁₆ are alkylene groups having 1 to 15 carbon atoms, and R ₃ and R ₄ are alkylene groups having 1 to 10 carbon atoms. The alkyl group R ₁₇ and R ₁₈ represent an alkyl group having 1 to 4 carbon atoms, and R ₁₇ and R ₁₈ may form a heterocyclic ring of the same nitrogen atom. _R15
represents an alkyl group having 1 to 3 carbon atoms or [Formula]. X represents a hydrogen atom or a hydroxyl group. 3. The manufacturing method according to claim 1, wherein the resin has a softening temperature of 100 to 160°C using a Koka type flow tester and a glass transition temperature of 50°C or higher.