JP3254017B2 - Binder resin for toner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a binder resin for toner used in electrophotography and electrostatic printing, and more particularly, it has excellent non-offset properties and chargeability, and can be used for ultra-high-speed printing. The present invention relates to a binder resin capable of providing a toner having excellent fixability.

[0002]

2. Description of the Related Art The market for copiers and printers by the electrophotographic method and the electrostatic printing method is roughly divided into a large-volume copying field requiring high-speed printing and a compact-size copying field requiring low energy. You. In the field of large-volume copying, there has been a demand for a toner which can be fixed at a low temperature and a sharp melt, and a binder resin thereof, due to an increase in printing speed. Further, the image characteristics, that is, the charging characteristics, must be stabilized in accordance with the printing speed. In particular, recently, there has been a demand for ultra-high-speed copiers and printers that perform printing at higher speeds than conventional high-speed printing, and those with better fixing properties as toner and its binder resin. Is becoming necessary. Further, the main component of the toner is a binder resin, and various properties of the toner largely depend on the binder resin to be used. Therefore, it is important to obtain a toner with an excellent binder resin design.

The design of a binder resin for a toner is roughly classified into a crosslinked resin containing a THF-insoluble component and a non-crosslinked resin containing no THF-insoluble component. The non-crosslinked resin has a characteristic molecular weight distribution, and is a resin form in which a high molecular weight polymer that improves non-offset properties and a low molecular weight polymer that improves fixing properties are mixed. It is often used in high-speed copiers. However, the low molecular weight component is excessively pulverized, causing a problem of poor image characteristics due to a change in the amount of charge with time, and a method of controlling the molecular weight of the low molecular weight component, a method of introducing a third component having a different molecular weight, and the like. However, even with such a method, problems such as impairing the fixing property arise.

On the other hand, crosslinked resins are often used in low-speed machines, which have a severe non-offset property due to their crosslinked structure.
Further, since the crosslinked resin has a higher elasticity effect than the non-crosslinked resin, it has a feature that it is hard to be excessively pulverized and has good image characteristics. On the other hand, since the resin has a crosslinked structure, there is a problem that the resin has a high melt viscosity and the fixability at low temperatures is impaired. As a method for improving the fixing property of the crosslinked resin, a method of introducing a low molecular weight polymer component, a method of controlling a crosslinked structure, and the like have been tried.

[0005]

However, in a resin into which a low-molecular-weight polymer component has been introduced, the resin has an insufficiently pulverizable property to cause a problem of charging property. Attempts have been made to solve the problem of chargeability by blending different polymers with different molecular weights, but to blend two polymers with different molecular weights and a polymer having a crosslinked structure. In addition, the mixed state of the resin becomes poor, and it becomes difficult to control the fixing property.

On the other hand, in a resin having a controlled cross-linking structure, the chargeability is easily controlled, but when the degree of cross-linking is reduced, the non-offset property becomes poor and the problem of fixing strength also arises. Further, when the degree of crosslinking is increased, there is a problem that the fixability becomes poor. SUMMARY OF THE INVENTION An object of the present invention is to provide a binder resin for a toner that solves the above-mentioned conventional problems and has excellent fixing characteristics and charging characteristics that can be used in an ultra-high-speed copier or printer.

[0007]

Means for Solving the Problems The present inventors have made intensive studies on a crosslinked styrene acrylic resin,
By controlling the degree of cross-linking of the resin and introducing a fixing property improving component that does not affect the charging properties by suspension polymerization, we have found a binder resin that can obtain a toner with excellent fixing properties and charging properties. is there. That is, the binder resin for toner of the present invention,
A styrene-based component, an acrylic-based component and / or a methacryl-based component as a main component, and a THF-insoluble content of 0.1 to 60;
In weight percent, in the molecular weight distribution by gel permeation chromatography of the solvent-soluble portion, the main peak was in a region of 1 × 10 ⁴ to 8 × 10 ⁴ in weight average molecular weight, and 500 or less in weight average molecular weight. The region has at least one peak.

The monomer component used in the binder resin of the present invention mainly contains a styrene component, an acryl component and / or a methacryl component as a main component. It is preferably used in the range of 60 to 90% by weight in the polymer component, and more preferably in the range of 65 to 85% by weight.
As long as the polymerizable vinyl monomer has a reactive double bond as another component, it can be used in combination with these components.

Examples of the styrene component include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, and 3,4-dichlorostyrene. , P-ethylstyrene, 2,4 dimethylstyrene, p
-N-butylstyrene, p-tertbutylstyrene,
pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, α-methylstyrene and the like. Among them, styrene, p-methylstyrene and α-methylstyrene are preferred. By using such a styrene component, it is possible to improve the moisture resistance of the toner.

The acrylic or methacrylic component includes acrylic acid, ethyl acrylate, methyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, and the like. Lauryl acrylate,
Acrylic components such as 2-ethoxyethyl acrylate, 2-methoxyethyl acrylate, 2-butoxyethyl acrylate, methacrylic acid, ethyl methacrylate, methyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, propyl methacrylate, methacrylic 2-ethylhexyl acrylate, stearyl methacrylate, lauryl methacrylate, glycidyl methacrylate, cyclohexyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate, 2-ethoxyethyl methacrylate, 2-methoxyethyl methacrylate, 2-butoxyethyl methacrylate And the like. Among them, n-butyl acrylate, 2-ethylhexyl acrylate, methacrylic acid, methyl methacrylate, n-butyl methacrylate, and 2-ethoxyethyl methacrylate are preferred.

Further, in addition to the above components, unsaturated dibasic acid components may be used. For example, maleic acid, butyl maleate, methyl maleate, dimethyl maleate, fumaric acid, butyl fumarate, dibutyl fumarate , Diisobutyl fumarate, dimethyl fumarate, diethyl fumarate and the like. Among them, dibutyl fumarate is preferred. In the present invention, the aromatic diol component is preferably used in the range of 0.5 to 10% by weight, more preferably in the range of 2 to 8% by weight, based on all polymer components. If the amount of the aromatic diol component is less than 0.5% by weight, the fixability of the toner tends to be insufficient.
If the amount exceeds the weight percentage, the blocking resistance of the toner tends to be inferior.

Examples of the aromatic diol component include bisphenol A derivative components, and specifically, bisphenol A, hydrogenated bisphenol A, polyoxypropylene- (2,4) -2,2-bis (4-hydroxy Phenyl) propane, polyoxyethylene- (2,4) -2,
2-bis (4-hydroxyphenyl) propane and the like. Among them, polyoxypropylene- (2,4)-
2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene = (2,4) -2,2-bis (4-hydroxyphenyl) propane are preferred, and these may be used in combination.

In the present invention, in order to adjust the softening temperature and the molecular weight of the obtained binder resin,
Chain transfer agents such as α-methylstyrene dimer, n-dodecyl mercaptan, thioglycolic acid ester, and n-octyl mercaptan can also be used. Among them,
α-Methylstyrene dimer and thioglycolic acid ester are preferred.

As the binder resin of the present invention, TH resin
It is necessary that the F-insoluble content is 0.1 to 60% by weight, preferably 10 to 55% by weight. This is because if the THF-insoluble content is less than 0.1% by weight, the non-offset property of the toner becomes insufficient, and if it exceeds 60% by weight, the fixability of the toner is inferior. By setting the THF-insoluble content in this range, a toner having a good balance between non-offset properties and fixability can be obtained. In order for the binder resin to have a THF-insoluble content, it is necessary to use a crosslinking agent component. Examples of the crosslinking component include a reactive vinyl monomer, oligomer or polymer having two or more reactive double bonds in one molecule, a crosslinking agent containing many reactive double bonds in one molecule, and the like.

Examples of the reactive vinyl monomer, oligomer or polymer having two or more reactive double bonds in one molecule include aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene, and ethylene glycol di (meth) acrylate. , Triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, dipropylene glycol di (meth)
Acrylate, 1,3-butylene glycol di (meth)
Acrylates and bisphenol A derivative-based di (meth) acrylates are exemplified. Among them, divinylbenzene and 1,3-butylene glycol dimethacrylate are preferred.

Examples of the crosslinking agent containing a large number of reactive double bonds in one molecule include an unsaturated polyester oligomer or polymer of an unsaturated dicarboxylic acid component and a bisphenol A derivative component. Examples of the unsaturated dicarboxylic acid component include fumaric acid, maleic acid, maleic anhydride, and itaconic acid, and fumaric acid is particularly preferably used. In addition to these unsaturated dicarboxylic acids, terephthalic acid, isophthalic acid, sebacic acid,
A dicarboxylic acid such as adipic acid may be used as long as it is in a range of 15 mol% or less in all dicarboxylic acid components. Examples of the bisphenol A derivative component include bisphenol A, hydrogenated bisphenol A, polyoxypropylene- (2,4) -2,2-bis (4-hydroxyphenyl) propane, and polyoxyethylene- (2,
4) -2,2-bis (4-hydroxyphenyl) propane and the like, particularly preferably polyoxypropylene- (2,4) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene- (2,4) -2,
2-bis (4-hydroxyphenyl) propane,
You may use both together. In addition, these bisphenol A
In addition to derivatives, ethylene glycol, neopentyl glycol, butanediol and the like may be used.

These crosslinking agents are preferably used in an amount of from 0.5 to 3% by weight, more preferably from 0.8 to 2.7% by weight, based on all polymer components. If the cross-linking agent component is less than 0.5% by weight, the cross-linking structure of the binder resin tends to be insufficient, and the non-offset property of the toner tends to be inferior. This is because the fixability of the toner tends to be impaired.

In the binder resin of the present invention, in the molecular weight distribution of the solvent-soluble portion of the binder resin by gel permeation chromatography, the weight average molecular weight is in the range of 1 × 10 ⁴ to 8 × 10 ⁴ , preferably 6 × 10 ^4.
It is important to have a main peak in a region of × 10 ^{3 to} 6 × 10 ⁴ and one or more peaks in a region having a weight average molecular weight of 500 or less. A binder resin having such a molecular weight distribution is excellent in sharp melt property and extremely excellent in toner fixability. In particular, by having a peak in a low molecular weight region having a weight average molecular weight of 500 or less, excellent fixability that can be used in a copier or a printer for ultrahigh-speed printing is obtained. In addition, since the binder resin having such a molecular weight distribution contains a specific amount of a THF-insoluble component, a binder resin having a uniform and regular crosslinked structure can be obtained, and the fixing property, non-offset property and charging property of the toner can be obtained. Will be excellent.

The binder resin of the present invention has a glass transition temperature of 45 to 68 ° C. and a softening temperature of 110 to 170.
It is preferable that the acid value is in the range of 25 mgKOH / g or less. This is because if the glass transition temperature is lower than 45 ° C., the blocking resistance of the toner is inferior, and if it exceeds 68 ° C., the fixability of the toner is impaired, and the temperature is more preferably in the range of 50 to 65 ° C. The softening temperature is 110 ° C
If it is less than 170 ° C., the non-offset property of the toner is inferior, and if it exceeds 170 ° C., the fixability of the toner is inferior, and it is more preferably in the range of 115 to 165 ° C. Further, when the acid value is 2
If it exceeds 5 mgKOH / g, the moisture resistance of the toner is inferior, and more preferably 20 mgKOH / g or less.

In producing the binder resin of the present invention, general polymerization methods such as bulk polymerization, suspension polymerization, emulsion polymerization and solution polymerization can be used, and a polymerization method combining these polymerization methods can be used. Can also. Among them, suspension polymerization or a method in which suspension polymerization is combined with another polymerization method is preferable.

The polymerization temperature of the binder resin of the present invention is as follows:
70-150 ° C. is preferred, and the target molecular weight and THF
It is preferable to control according to the insoluble content and the softening temperature. In the present invention, the suspension polymerization is carried out by raising the temperature to the polymerization temperature for 15 to 90 minutes, preferably 20 to 80 minutes, in order to obtain a resin having a specific THF-insoluble component. preferable. This is because if the heating time is less than 15 minutes, it is difficult to obtain a resin having a THF-insoluble content, and a large amount of a crosslinking agent component is required. Conversely, if the heating time exceeds 90 minutes, the THF-soluble content becomes too high, and accordingly, the softening temperature also increases, and the fixability becomes poor.

In the present invention, a chain transfer agent such as α-methylstyrene dimer, n-dodecylmercaptan, thioglycolic acid ester and n-octylmercaptan is used to adjust the softening temperature and molecular weight of the binder resin. You can also. Among them, α-methylstyrene dimer and thioglycolic acid ester are preferable.

Further, the polymerization initiator used for producing the binder resin of the present invention is not particularly limited as long as it is one used for ordinary radical polymerization, but in order to achieve the object of the present invention. Is particularly preferably a peroxide-based polymerization initiator. Examples of the peroxide-based polymerization initiator include benzoyl peroxide, t-butylperoxyisobutyrate, t-butylperoxy 2-ethylhexanoate, t-butylperoxybenzoate, and t-butylperoxy. Isopropyl carbonate, di-t-butyldiperoxyisophthalate and the like can be mentioned, and these can be used alone or in combination. Among them, benzoyl peroxide and t-butyl peroxybenzoate are preferred.

The polymerization initiators other than peroxides that can be used in the present invention include 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 2,2 '-Azobis (2,4'-dimethylvaleronitrile), 1,1-bis (t-butylperoxy)
3,3,5-trimethylcyclohexane, 1,1-azobis (cyclohexane-1-carbonitrile), 2,
2′-azobis (2,4,4-trimethylpentane) and the like. Among them, 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis (2,4′-
Dimethyl valeronitrile) is preferred.

These polymerization initiators can be appropriately selected according to the polymerization temperature and the monomers used.
The amount of these components may be appropriately selected according to the softening temperature, glass transition temperature, and THF-insoluble content of the binder resin, but may be 1 to 10% by weight based on the total amount of all polymer components excluding the aromatic diol component. Is preferably used, and more preferably in the range of 2 to 8% by weight.

In producing the binder resin of the present invention, ordinary emulsifiers and dispersants can be used. As emulsifiers and dispersants, polyvinyl alcohol,
Examples thereof include sodium polyacrylate-based dispersants, polyether-based dispersants, and ethylene oxide-based dispersants. Further, dispersing aids such as sodium sulfate, sodium carbonate, aqueous hydrogen peroxide and boric acid can be used.

In the present invention, after the polymerization is completed, a distillation step for reducing residual monomers and an alkali treatment step for reducing by-products of the peroxide-based initiator may be performed. In the case of suspension polymerization or emulsion polymerization, the temperature in the system is set to about 100 ° C. or higher, and the distillation step is 5 to 35 with respect to the amount of water initially charged.
% By weight, preferably 10 to 30% by weight of deionized water and residual monomers are allowed to flow out of the reaction system. In the alkali treatment step, the temperature in the system is set to 85 to 110 ° C., preferably 90 to 105 ° C.
~ 2.5% by weight, preferably 0.5-2% by weight of alkali metal hydroxide is added and held for about 10 minutes to 3 hours, preferably 20 minutes to 2 hours 30 minutes. Here, examples of the alkali metal hydroxide include alkali metal hydroxides such as lithium, sodium, potassium, and rubidium, and among them, sodium hydroxide is preferable.

In the present invention, the glass transition temperature was determined by a DSC method (heating rate: 10 ° C./min) after the sample was heated to 100 ° C. and melt-quenched. The softening temperature was measured using a flow tester CFT-500 (manufactured by Shimadzu Corporation) having a nozzle of 1 mmφ × 10 mm, when 1/2 of the sample amount flowed out under the conditions of a load of 30 kgf and a heating rate of 3 ° C./min. Temperature.
The acid value was determined using a titration method using KOH.

The molecular weight was determined by gel permeation chromatography HCL-8020 (manufactured by Tosoh Corporation) in terms of polystyrene. In detail, regarding the measuring method in the molecular weight measurement, the calculation of the molecular weight and the molecular weight distribution were obtained from the relationship between the calibration curves prepared from several types of monodisperse polyethylene standard samples and the counted values. At this time, the polyethylene standard sample had a molecular weight of 6 × 10
² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ ,
5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ ,
Examples include 8.6 × 10 ⁵ , 2 × 10 ⁶ , and 4.48 × 10 ⁶ , and it is preferable to select and use 10 or more. In addition, columns TSKgel, G1000H, G20
00H, G2500H, G3000H, G4000H,
G5000H, G6000H, G7000H, GMH, and the like can be mentioned, and it is preferable to use them in combination.

The THF-insoluble matter was prepared by placing 0.5 g of a sample in 50 ml of tetrahydrofuran (THF), heating and dissolving at 60 ° C. for 3 hours, filtering through a glass filter lined with Celite # 545, and using a vacuum dryer at 80 ° C. The weight when sufficiently dried was indicated by a value obtained by dividing the weight by the initial weight.

[0031]

The present invention will be specifically described below with reference to examples. In the embodiment, the charging stability is determined by using a copying machine in which the temperature and speed of the fixing roller can be varied, and controlling the fixing roller temperature to each fixing temperature.
A print test was performed on 00 sheets, and the initial charge amount and 10,000
The charge amount after printing was measured by a blow-off charge measuring device. As a result, the difference between the initial charge amount and the charge amount after printing 10,000 sheets was evaluated according to the following criteria.

A: Charge amount difference of less than 1 μC / g O: Charge amount difference of 1 μC / g or more and less than 2 μC / g Δ: Charge amount difference of 3 μC / g or more and less than 4 μC / g X: Charge amount difference of 4 μC / g or more The fixing temperature was measured using a fixing tester capable of freely changing the temperature and speed, and the results were evaluated according to the following criteria.

◎: less than 140 ° C. ○: 140 to 159 ° C. Δ: 160 to 179 ° C .: 180 ° C. or more For non-offset property, use a fixing tester capable of freely changing temperature and speed. The generation temperature was measured, and the result was evaluated according to the following criteria.

◎: 210 ° C. or more ：: 195 to 209 ° C. Δ: 180 to 194 ° C. ×: less than 180 ° C. For blocking resistance, about 1 g of the toner was placed in a glass container and placed in a hot air dryer kept at about 50 ° C. After standing for about 48 hours, the aggregation state of the toner when the glass container taken out was inverted was evaluated according to the following criteria.

◎: The toner is uniformly dispersed. ト ナ ー: The toner is uniformly dispersed when hit twice. Δ: The toner is uniformly dispersed when hit four times. X: The toner is not aggregated and dispersed. In the evaluation of moisture resistance, fixing property, non-offset property and blocking resistance, those having ◎ to △ are practically usable.

Preparation of Dispersant A A reaction vessel equipped with a stirrer, thermometer, and gas inlet tube was charged with 2,300 parts by weight of deionized water, 25 parts by weight of methyl methacrylate, and 75 parts by weight of 3-sodium sulfopropyl methacrylate. , N ₂ gas was blown in for about 30 minutes to expel air in the reaction system. Then, the mixture was heated from the outside with a hot water bath while stirring, and the temperature was raised to 60 ° C.
Parts by weight were added. When stirring was continued at the same temperature for about 3 hours, the mixture exhibited a bluish white appearance and a viscosity of 340 centipoise (2
5 ° C.) (solid content: 3.3% by weight).

Example 1 220 parts by weight of deionized water, 6.1 parts by weight of dispersant A, 1.5 parts by weight of sodium polyacrylate (3.3% solids) and 1 part by weight of sodium sulfate were mixed and dissolved, and distilled. It was charged into a reaction vessel equipped with a tower and a stirrer. Then, Table 1
Each component of the polymer composition as shown in (1) was sufficiently mixed and dissolved and charged into a reaction vessel. Furthermore, the stirring rotation speed is 200r
pm and the initiators shown in Table 1 were added. About 30
After maintaining this state for minutes, the temperature was raised. About 30 minutes after the start of the temperature increase, the temperature in the reaction system was set to 88 ° C., and the suspension polymerization was started. Approximately 3 hours after the start of the suspension polymerization, the reflux was completed and the heat generation was completed, so the suspension polymerization was completed. Next, the distillation column was changed to a Liebig condenser, the temperature in the reaction system was raised to 100 ° C., and the process was shifted to a distillation step. A mixed solution of deionized water and the remaining monomer was allowed to flow out of the reaction system for about 2 hours, and about 20% by weight of the charge at the time of charging was flowed out. Further, while maintaining the temperature in the reaction system at about 90 ° C., the weight was changed from a Liebig condenser to a distillation column, and 5 parts by weight of sodium hydroxide was added to carry out an alkali treatment for about 30 minutes. Thereafter, the temperature in the reaction system was cooled to room temperature, and the obtained resin was taken out and dried at 50 ° C. for about 48 hours to obtain a binder resin. The obtained resin had a glass transition temperature (Tg), a softening temperature, an acid value, a THF-insoluble matter and a molecular weight distribution as shown in Table 2.

Further, 92 parts by weight of the obtained binder resin, 4 parts by weight of carbon black, 1 part by weight of a negative charge control agent and 3 parts by weight of a low-molecular-weight PP wax were mixed and heated at a temperature 10 ° C. higher than the softening temperature. The mixture was melt-kneaded using a pressure-type two-roll mixer. Then, fine grinding,
Classification was performed to obtain a toner having an area average particle size of 10 to 12 μm. Using the obtained toner, the fixing speed was set to 600 mm /
In seconds, the fixing property, the non-offset property, the anti-blocking property and the charging stability were evaluated. The results are shown in Table 2.

Example 2 Each component having the polymer composition shown in Table 1 was used, and the blending amount of polyvinyl alcohol was changed to 0.8 in place of the dispersant A.
A binder resin was obtained in the same procedure as in Example 1 except that the polymerization temperature was set to 130 ° C., except that the heating time to the polymerization temperature was 45 minutes and the polymerization temperature was 45 parts by weight. The obtained resin had a glass transition temperature (Tg), a softening temperature, an acid value, a T
It had HF insolubles and molecular weight distribution. Using the obtained binder resin, a toner was obtained in the same procedure as in Example 1. Using the obtained toner, a fixing speed of 600
The fixing performance, non-offset property, blocking resistance and charging stability were evaluated as mm / sec.
It was shown to.

Examples 3 and 4 Using the components of the polymer composition shown in Table 1, the temperature was raised to the polymerization temperature for 45 minutes, and the polymerization temperature was set to 130.
A binder resin was obtained in the same procedure as in Example 1 except that the temperature was changed to ° C. The obtained resin had a glass transition temperature (Tg), a softening temperature, an acid value, a THF-insoluble matter and a molecular weight distribution as shown in Table 2. Using the obtained binder resin, a toner was obtained in the same procedure as in Example 1. Using the obtained toner, fixing performance, non-offset performance, blocking resistance, and charging stability were evaluated at a fixing speed of 600 mm / sec, and the results are shown in Table 2.

As is clear from Table 2, the toners of Examples 1 to 4 using the binder resin of the present invention are superior in fixing property to those of Examples 1, 2 and 3;
The toner of Example 4 was slightly inferior, but at a usable level, and all toners exhibited sufficient fixing characteristics even at ultra-high speed printing. Regarding the non-offset property, Example 4
The toner of Example 1 was excellent, the toner of Example 1 was good, and the toners of Examples 2 and 3 were slightly inferior but usable. With respect to blocking resistance, the toner of Example 2 was excellent, the toners of Examples 1 and 4 were good, and the toner of Example 3 was slightly inferior but at a usable level. With respect to charging stability, the toner of Example 2 was excellent, and the toners of Examples 1 and 4 were good.
The toner of Example 3 was slightly inferior but at a usable level.

COMPARATIVE EXAMPLES 1 AND 2 Each component having the polymer composition shown in Table 1 was used, the temperature was raised to the polymerization temperature for 45 minutes, and the polymerization temperature was set to 130.
A binder resin was obtained in the same procedure as in Example 1 except that the temperature was changed to ° C. The obtained resin had a glass transition temperature (Tg), a softening temperature, an acid value, a THF-insoluble matter and a molecular weight distribution as shown in Table 2. Using the obtained binder resin, a toner was obtained in the same procedure as in Example 1. Using the obtained toner, fixing performance, non-offset performance, blocking resistance, and charging stability were evaluated at a fixing speed of 600 mm / sec, and the results are shown in Table 2.

As is clear from Table 2, the toner of Comparative Example 1 had good non-offset properties, anti-blocking properties and charging stability, but was inferior in fixability and could not be used. The toner of Comparative Example 2 was excellent in charge stability, good in anti-blocking properties, and slightly inferior in non-offset properties, but was inferior in fixability and was not usable.

[0044]

[Table 1]

[0045]

[Table 2]

The symbols of the monomers and initiators shown in Table 1 represent the following compounds, respectively. St; styrene n-BA; n-butyl acrylate ET; 2-ethoxyethyl methacrylate BPP; polyoxypropylene- (2,4) -2,2
-Bis (4-hydroxyphenyl) propane propylene oxide 2.5 mol adduct BP3; polyoxypropylene- (2,4) -2,2
-Bis (4-hydroxyphenyl) propane propylene oxide 4 mol adduct BDMA; 1,3-butylene glycol dimethacrylate PB; polyoxyethylene- (2,4) -2,2-
Unsaturated polyester resin composed of bis (4-hydroxyphenyl) propane and fumaric acid BPO; benzoyl peroxide tBP; t-butylperoxybenzoate

[0047]

The binder resin for a toner of the present invention comprises:
By having a specific THF-insoluble content and a specific molecular weight distribution, it is possible to obtain a toner having excellent non-offset properties, anti-blocking properties and charging properties, as well as extremely excellent fixing properties. It can handle high-speed copiers and printers.

Continuation of the front page (56) References JP-A-1-219769 (JP, A) JP-A-4-66957 (JP, A) JP-A-59-45449 (JP, A) JP-A-2-5070 (JP, A) , A) JP-A-63-223014 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/08

Claims (3)

(57) [Claims] 1. A molecular weight based on gel permeation chromatography containing a styrene-based component, an acrylic-based component and / or a methacryl-based component as a main component, a THF-insoluble content of 0.1 to 60% by weight, and a solvent-soluble content. In the distribution,
A binder resin for toner having a main peak in a region of 1 × 10 ⁴ to 8 × 10 ⁴ in weight average molecular weight and at least one peak in a region of 500 or less in weight average molecular weight. 2. An aromatic diol component is contained in the whole polymer in an amount of 0.5 to 10% by weight.
The binder resin for toner described in the above. 3. The binder resin for a toner according to claim 1, wherein the glass transition temperature is 45 to 68 ° C., the softening temperature is 110 to 170 ° C., and the acid value is 25 mgKOH / g or less.