JPS61209226A - Production of binder resin - Google Patents

Abstract

PURPOSE:To obtain the titled resin for electrostatic charge developer having excellent offset-resistance and fixability in the heat-roller fixing process and high pulverizability, etc., by carrying out the copolycondensation of a specific diol component with an acid component containing a specific polybasic carboxylic acid. CONSTITUTION:The objective resin can be produced by the copolycondensation of (A) a diol component of formula I (R is ethylene or propylene; x and y are integer of >=1, and average value of x+y is 2-7) with (B) an acid component obtained by adding (i) a polybasic carboxylic acid (anhydride) or its lower alkyl ester obtained by the copolymerization of alpha-methylstyrene and/or the compound of formula II (R1 is 1-3C hydrocarbon group or H) (e.g. styrene) with the compound of formula III (R2 and R3 are H, methyl or COOH) (e.g. maleic acid) to (ii) a >=2-basic carboxylic acid (anhydride) or its lower alkyl ester. The component A is e.g. polyoxyethylene(2,0)-2,2-bis(4-hydroxyphenyl) propane, etc.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a binding resin, and more specifically, for developing electrostatic images in electrophotography, electrostatic recording, electrostatic printing, etc. The present invention relates to binding resins particularly useful in developer compositions for

[Conventional technology and problems]

As a conventional electrophotographic method, as described in U.S. Patent Nos. 2,297,691 and 2,357,809, 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, which is then coated with a colored pigment called toner. After the visible image is transferred to a transfer material such as transfer paper (transfer process), it is heated,
It consists of a step of permanently fixing (fixing step) by pressure or other suitable fixing method.

In this way, toner is used not only in the development process but also in the transfer process.
It must have the functions required in each step of the fixing process.

Generally, toner is subjected to mechanical frictional force due to shearing force and impact force during mechanical operation in a developing device, and deteriorates during copying of tens 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 are suitable for non-contact fixing methods such as oven fixing and infrared fixing. With radiant fixing, the thermal efficiency is poor, so fixing is not sufficient.Also, since the contact fixing method has good thermal efficiency, even in the widely used heat roller constant fixing method, it is necessary to use the heat roller to achieve sufficient fixing. It becomes necessary to raise the temperature, which not only causes adverse effects such as deterioration of the fixing device, curling of paper, and increased energy consumption, but also causes a significant drop in production efficiency when producing toner by pulverizing such resins. descend. 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 fixed 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 the surfaces come into contact, a so-called offset phenomenon tends to occur, in which toner adheres to the surface of the heating roller and is transferred to a 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 etc.
The fixing device is not preferable because it is thick (which not only increases cost but also complicates it and is likely to cause trouble).

In addition, as described in Japanese Patent Publication No. 55-6895 and Japanese Patent Application Laid-open No. 56-98202, there is a method to improve the offset phenomenon by widening the molecular weight distribution width of the binder resin, but the degree of polymerization of the resin increases and the fixation becomes difficult. The temperature also needs to be high.

As a further improved method, as described in Japanese Patent Publication No. 57-493, Japanese Patent Application Publication No. 50-44836, and Japanese Patent Application Publication No. 57-37353, there is a method of improving the offset phenomenon by making the resin asymmetrical and crosslinking. However, the retention point has not improved.

Generally, the minimum fusing temperature is the same for cold offset and hot offset.
Because it is located between the nozzles, the usable temperature range is between the minimum fixing temperature and hot offset, so lower the minimum fixing temperature as much as possible, and raise the minimum hot offset temperature as much as possible to lower the usable fixing temperature. It is possible to expand the usable temperature range, save energy, achieve high-speed fixing, and prevent paper from curling. In addition, since double-sided copying can be performed without trouble, there are many advantages such as making the copying machine more intelligent, controlling the temperature of the fixing device more accurately, and 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 Nos. 49-65232 and 1972
As described in No. 0-28840 and JP-A No. 50-81342, methods of adding paraffin wax, low molecular weight polyolefin, etc. as anti-offset agents are known; In the case of polyester resin, even if the above-mentioned anti-offset agent is applied, it has little effect (it has been confirmed that the developer deteriorates more quickly if the amount used is large).

Polyester resin inherently has good fixing properties, and can be sufficiently fixed even in a non-contact fixing method as described in U.S. Pat. was difficult to use.

Japanese Patent Application Publication No. 5'〇-44836, Japanese Patent Application Publication No. 57-37353
As described in JP-A-57-109875, polyester resins that use polyhydric carboxylic acids and have improved offset resistance either do not have sufficient offset resistance to be used, or do not have sufficient offset resistance. Not only do they sacrifice the low-temperature fixing properties inherent to polyester resins, but they also have extremely poor pulverization properties in the toner production process, causing problems in developer production.

The present invention has been made to meet these demands, and its purpose is to prevent offset without applying an anti-offset liquid in a heat roller constant fixing method, to enable fixing at a lower fixing temperature, and to improve development speed. It is an object of the present invention to provide a binder resin for a developer that has good kneading and pulverizing properties during the production of the developer.

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 provide a dry developer for electrophotography,
The object of the present invention is to provide a toner binder resin that is inherently negatively charged (electrostatically charged) to provide a toner that forms sharp, fog-free images, and more particularly, to provide a toner binder resin that is highly resistant to the effects of environmental humidity, improving the above-mentioned drawbacks. The object of the present invention is to provide a binder resin for toner that is small, has excellent durability, and has negative triboelectric charging properties.

Another object of the present invention is to provide a method for producing a binding resin used in a clear color developer with good transparency.

Another object of the present invention is to provide a method for producing a binder resin used in a developer that does not cause fusion with the file or transfer of images to the film even when stored in a file.

[Means for solving problems]

The present inventors have arrived at the present invention as a result of intensive research to achieve the above object.

That is, the present invention relates to (a) the following general formula (wherein R represents ethylene or propylene group, x, y
each represents an integer of 1 or more, and the average value of x+y is 2 to 7. ) and (b) an acid component which is a divalent or higher carboxylic acid, an acid anhydride thereof, or a lower alkyl ester thereof. is α-methylstyrene or/and a compound represented by the following general formula (in the formula, R1 represents a hydrocarbon group having 1 to 3 carbon atoms or hydrogen) and the following general formula (in the formula, Rz, R3 represents hydrogen, a methyl group, or a carboxyl group), or an acid anhydride thereof, or a lower alkyl ester thereof. The present invention relates to a method for producing a synthetic resin.

As the diol component (a) in the present invention, for example, polyoxypropylene (2,2) -2,2-bis(4
-hydroxyphenyl)propane, polyoxypropylene (3,3)-2,2-bis(4-hydroxyphenyl)propane, polyoxyethylene (2,0) -2,
2-bis(4-hydroxyphenyl)propane, polyoxypropylene (2,0) ・-polyoxyethylene (
2,0)-2,2-bis(4-hydroxyphenyl)propane, polyoxyethylene(6)-2,2-bis(4
-hydroxyphenyl)propane and the like.

In addition, other polyols may be used, such as polyoxypropylene (12)-2,2-bis(4-hydroxyphenyl)propane, polyoxyphenylethylene (3)-2, if necessary.
, 2-bis(4-hydroxyphenyl)propane, ethylene glycol, diethylene glycol, propylene glycol, triethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, heptamethylene glycol, octamethylene glycol, nonamethylene glycol, decamethylene Glycol, neopentyl glycol, p-xylylene glycol, m-xylylene glycol, 1,4-cyclohexane dimetatool, 1,4-cyclohexane jetanol, 1.4-cyclohexane diol, 1.3-
Cyclohexane dimetatool, glycerin, polyoxytylene (6) glycerin, polyoxypropylene (12
) Pentaerythritol, etc. can be added to the polyol component in an amount of about 10 mol% or less, but if the reaction is highly sterically hindered such as polyoxyphenylethylene (3) -2゜2-bis(4-hydroxyphenyl)propane, the reaction will not proceed. Resins containing highly hydrophilic polyols such as glycerin and polyoxyethylene (6) pentaerythritol tend to deteriorate the image quality of the developer, so care must be taken.

Further, in the present invention, examples of the compound represented by formula (Ila) include styrene, methylstyrene, ethylstyrene, propylstyrene, and the like.

Further, in the present invention, examples of the compound represented by formula (nb) include maleic acid, fumaric acid, acrylic acid, methacrylic acid, and itaconic acid. These may be acid anhydrides or esters of lower alkyl groups.

The meaning of the lower alkyl group herein is an alkyl group of such a size that the alkyl of the alkyl ester does not interfere with the copolymerization of the compound of formula (II a) and the compound of formula (II b).

Further, the compound of formula (IIa) is preferably used in an amount of 1 to 5 mol per 1 mol of the compound of formula (IIb) for copolymerization.

Specific examples of polyhydric carboxylic acid (n) in the present invention are shown below, but in order to control the reaction and get close to the required performance,
It is also possible to use one in which a part of the carboxylic acid group is substituted with an alkyl ester.

These polyhydric carboxylic acids (II) or their acid anhydrides or their lower alkyl esters are contained in the acid component in an amount of 0.05 to 70%.
The content is preferably mol%.

In addition, the acid component of the present invention includes the following general formula (III) R
a II OOH (wherein R4 is an alkyl group or alkenyl group having 4 to 18 carbon atoms) The alkyl or alkenyl group represented by (R4 is an alkyl group or alkenyl group having 4 to 18 carbon atoms) may contain an acid, an acid anhydride thereof, or a lower alkyl ester thereof.

Examples of alkyl or alkenyl succinic acids include n-dodecenyl succinic acid, isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octyl succinic acid, and n-octyl succinic acid.
acid, n-octenylsuccinic acid, n-butylsuccinic acid, and the like. By using alkyl or alkenyl succinic acid, it is possible to lower the minimum fixing temperature without lowering the offset generation temperature, but if there is too little, the effect will be weak.
If the amount is too large, the Tg will decrease and toner caking will occur easily (and the reaction will be difficult to control. Therefore, the content is preferably 1 to 5% in the acid component).
It is 0 mol%. In addition, divalent carboxylic acids other than alkyl or alkenyl succinic acid groups that can be used in the present invention include:
Examples include fumaric acid, maleic acid, adipic acid, speric acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, and the like.

The softening point (AS) of the binding resin obtained by the method of the present invention
Ring and ball softening point according to THE-28-51T) is 90~
180°C is preferred.

The binding resin obtained according to the present invention is used in toners for electrostatic charge development produced by conventional methods.

That is, the resin produced according to the present invention can be mixed with various carbon blanks produced by a thermal black method, an acetylene black method, a channel black method, a furnace black method, a lamp blank method, etc. in the case of a black toner, as a coloring agent in the resin. For color toners, copper phthalocyanine, monoazo pigments (C, 1, PigIlent R
ed 5+C, 1, Pigment Orange
36. C, 1, Pigment Red 2
2), disazo pigment (C,1, Pigment Ye
low 83), anthraquinone pigments (C, 1, P
igment Blue 60), disazo dye (S
solvent Red 19), rhodamine dye (S
Olvent Red 49) and the like are added thereto and sufficiently uniformly dispersed using a ball mill or the like, then melt-kneaded using a kneader, cooled and pulverized, and used as a toner having an average particle size of 5 to 15 μm.

Further, magnetic fine powder can also be used in the developing mechanism or for the purpose of improving images. Examples of the magnetic powder include alloys or compounds containing elements exhibiting ferromagnetism, such as ferrite and magnetite, and the magnetic powder has an average particle size of 0.
It can be used in the form of a fine powder of 0.5 to 1 μm in size and dispersed in a binder resin in an amount of 30 to 70% by weight.

Further, as well-known property improving agents contained in the toner using the binding resin according to the present invention, there are anti-offset agents, fluidizing agents, etc., but their use as appropriate does not impede the present invention in any way.

〔Example〕

Examples of the present invention will be described below, but the present invention is not limited to these examples.

Example 1 Polyoxypropylene (2,2)-2,2-bis(4-
3.5 kg of (hydroxyphenyl)propane, 1.04 kg of fumaric acid, 132 g of dodecenyl succinic anhydride, and the above compound (IHlog) as polyhydric carboxylic acid (If) were placed in a glass 51 four-bottle flask with 3 g of hydroquinone, and a thermometer, A stainless steel stirring bar, a dehydration tube equipped with a reflux condenser tube, and a nitrogen introduction tube were attached, and the reaction was carried out with stirring at 200°C under a nitrogen stream in an electric heating mantle.The degree of polymerization was ASTM E28-51T. The reaction was followed when the softening point reached 125°C.The obtained resin was a pale yellow solid, and the DS
The glass transition temperature measured by C (differential calorimeter) was 59°C.

Example 2 Polyoxyethylene (2)-2,2-bis(4-hydroxyphenyl)propane1. ．． 58kg, polyoxypropylene (2,2)-2,2-bis(4-hydroxyphenyl)propane 1, 78kg, terephthalic acid 83
0g, fumaric acid 464g, dodecenylsuccinic anhydride 1
32g and the above compound (as polycarboxylic acid (II))
2,062 g of the resin was put into the same apparatus as in Example 1 along with 3 g of hydroquinone, and a resin was produced in the same manner as in Example 1. The reaction was terminated when the softening point reached 125°C. The obtained resin was a pale yellow solid and had a glass transition point of 60°C.

Example 3 Polyoxypropylene (2,2)-2,2-bis(4-
Hydroxyphenyl)propane 2848g 12.2-
208 g of dimethyl-1,3-propanediol, 928 g of fumaric acid, 264 g of dodecenyl succinic anhydride, and 616 g of the above compound (3) as the polycarboxylic acid (I[).
゜5g was placed in the same equipment as in Example 1 along with 3g of hydroquinone, and a resin was produced using the same procedure, until the softening point was 1.
The reaction was terminated when 23°C was reached. The obtained resin was a pale yellow solid with a glass transition temperature of 62°C.

Example 4 Polyoxypropylene (2,2)-2,2-bis(4-
3560 g of hydroxyphenyl)propane - 1245 g of isophthalic acid, 104 g of octyl succinic anhydride and the above compound (4) 17 as the polycarboxylic acid (I[)
17g was placed in the same equipment as in Example 1 along with 3g of hydroquinone, and a resin was produced in the same manner as in Example 1.
The reaction was terminated when 25°C was reached. The resulting resin was a pale yellow solid with a glass transition temperature of 65°C.

Comparative Example 1 A resin was produced by the same method as in Example 1 except that compound (1) was removed and fumaric acid was increased to adjust the ratio of carboxyl groups to hydroxyl groups, that is, 1102 g, and softened. The reaction was terminated when the temperature reached 125°C. The obtained resin was a pale yellow solid with a glass transition temperature of 58°C.

Comparative Example 2 A resin was produced in exactly the same manner as in Example 1 except that 110 g of trimellitic acid was added instead of compound (1), and the reaction was terminated when the softening point reached 125°C. The resulting resin is a pale yellow solid with a glass transition temperature of 5.
The temperature was 9°C.

Evaluation Example 1 90 parts by weight of the resin obtained in Example 1 and 10 parts by weight of carbon black (Su-Gal 400R manufactured by Cabot Corporation) were mixed in a ball mill, then kneaded, pulverized, and classified to obtain an average particle size of 12.5μ. I got the toner. The obtained toner was coated with carrier iron powder (manufactured by Nippon Iron Powder Co., Ltd.; IEFV 200/300
), and the amount of charge was measured using a blow-off type charge amount measuring device, and it was found to be -23 μc/g.

91 g of the toner was mixed with carrier iron powder (manufactured by Nippon Tetsuko Co., Ltd.; E
FV 200/300) 1209g to prepare a developer, and use a commercially available electrophotographic copying machine (using an amorphous selenium photoconductor, the rotation speed of the roller is 255 mm/sec, and the temperature of the heat roller in the fixing device is variable). When the image was produced using the same machine (with the oil applicator removed), a clear image was obtained with no background smudges, smearing, or missing solid black areas. Adjust the fixing temperature of the fixing device to 140°C to 220°C.
When the fixing properties and offset properties of the image were evaluated, the image was sufficiently fixed at 142° C. and no hot offset occurred. When images were printed up to 50,000 sheets, clear images were obtained with no background fogging or missing solid black areas.

Here, the minimum fixation area of 1 degree is the bottom surface of 15 mm x 7.
A 500g load was placed on a 5n+m 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 fixation rate was determined as defined below. This refers to the temperature of the fixing roller when the temperature exceeds 70%.

(However, the image density before rubbing is assumed to have an OD value of 0.50.) Evaluation Examples 2 to 6 The resins obtained in Examples 2 to 4 and Comparative Examples 1 to 2 were also evaluated in exactly the same way. The results are shown in Table 1. Note that the results of Evaluation Example 1 are also shown.

Table 1 Umbrella Relative comparison when the production amount per unit time when using the resin of Example 1 is 1.00 □ (□ Kaoru Furuya

Claims (1)

[Claims] 1 (a) The following formula ▲ Numerical formula, chemical formula, table, etc. ▼ (I) (In the formula, R represents an ethylene or propylene group, x and y each represent an integer of 1 or more, and The average value of x+y is 2 to 7.) A diol component represented by In the method for producing adhesive resin, the acid component is α-methylstyrene or/and the following general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (IIa) (In the formula, R_1 is carbonized carbon having 1 to 3 carbon atoms. There are compounds represented by the following general formula ▲ mathematical formula, chemical formula, table, etc. ▼ (IIb) (wherein R_2 and R_3 represent hydrogen, methyl group, or carboxyl group). 1. A method for producing a binding resin, comprising a polyhydric carboxylic acid (II), an acid anhydride thereof, or a lower alkyl ester thereof, which is a copolymer with a compound containing a polyhydric carboxylic acid (II). 2. The manufacturing method according to claim 1, wherein the acid component contains a divalent carboxylic acid represented by the following general formula (III), an acid anhydride thereof, or a lower alkyl ester thereof. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (III) (However, R_4 is an alkyl group or alkenyl group having 4 to 18 carbon atoms) 3 Polyhydric carboxylic acid (II) or its acid anhydride or its lower alkyl ester Content is 0.05-70 in acid component
mol%, and the ring and ball softening point of the binding resin is 90 to 18.
The manufacturing method according to claim 1, wherein the temperature is 0°C. 4. The manufacturing method according to claim 1, wherein the content of the divalent carboxylic acid represented by the general formula (III), its acid anhydride, or its lower alkyl ester is 1 to 50 mol% in the acid component.