JP2000242034A - Positive charge type toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positive charge type toner superior in resistances to occurrences of smears and offset and filming, and superior in quick rising in initial charging and charge stability. SOLUTION: The positive charge type toner comprises (A) a binder resin containing no positive chargeable factor, (B) a polymer obtained by copolymerizing a vinyl monomer with a quaternary amino chloride monomer (MTAS, for instance) in a polymerization weight ratio of 7:3-9:1, (C) a polymer obtained by copolymerizing a vinyl monomer with an amino monomer in a polymerization weight ratio of 5:5-7.5:2.5, and (D) a polypropylene wax and a polyethylene wax.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positively chargeable toner used in the field of electrophotography and the like.

[0002]

2. Description of the Related Art Conventionally, as a positively chargeable toner, for example, a toner in which a positive charge control agent such as a nigrosine dye, a quaternary ammonium salt, or triphenylmethane is added to a styrene-acrylic resin is known. However, when such a positively chargeable toner is used in a two-component developer used with a magnetic carrier, the positive charge control agent, which is a toner component, is spent on the surface of the magnetic carrier during repeated use for a long period of time, and the carrier of the carrier is used. There has been a problem that the frictional charging ability with respect to the toner is reduced and toner fog is generated in a non-image portion of an image.

[0003] There have been many reports on charge control in positively chargeable toners. For example, JP-A-62-291667 discloses that a conventional charge control agent such as a nigrosine dye, a quaternary ammonium salt or a positive charge control agent such as triphenylmethane is not contained and an amino group is contained as a binder resin. A toner using a resin has been reported.

In Japanese Patent Application Laid-Open No. 62-21169, amino (meth) acrylic monomers 1 to 1 are used as charge control agents.
A toner using a quaternary ammonium salt in combination with a copolymer or polymer of 00% by weight and 99 to 0% by weight of styrene has been reported.

JP-A-3-15079 discloses, as a charge controlling agent, a block and / or graft copolymer of a styrene-based polymer with a polymer comprising a monomer having a quaternary salt of an amino group, and optionally a quaternary ammonium. A toner using a salt or the like has been reported.

In Japanese Patent Application Laid-Open No. 8-220809, 1-30% by weight of methacryloyloxytrimethylammonium sulfate and a vinyl monomer 9 are used as a charge controlling agent.
A toner using a copolymer of 9 to 70% by weight is disclosed.

However, in any of the toners, the problem of fogging or the like caused by the deterioration of the charging stability as described above is not completely solved, or the initial charge rising property is reduced, and the desired charge amount at the time of startup is reduced. Is not obtained, and a new problem arises in that fogging occurs on the copied image at the initial stage, and it is difficult at present to achieve both excellent charging stability and initial charging startability.

As for the fixing method using toner, for example, a part of the toner constituting an image is transferred to the surface of the hot roll at the time of fixing by the hot roll fixing method, and is transferred again to the next transfer paper. As a result, the occurrence of an offset phenomenon that contaminates the image is a problem. As a technique for preventing this offset phenomenon, for example, a technique in which polypropylene wax is added to a toner as an anti-offset agent (release agent) is known (for example, JP-A-49-65).
No. 231).

Further, in recent years, with the increase in the copying speed of electrophotography and the increase in the number of functions, a copying machine equipped with an automatic current feeder and a duplex copying machine has become a standard. When the original is fed by these devices, or when the back side copy or multi-color copy
In the second copying process, the surface of the copied image is rubbed by a roller at the time of paper feeding, causing problems such as bleeding and dirt on the image. One copy of a plurality of copied images is stored temporarily in a copying machine by a paper feed roller for the second copy.
A similar phenomenon is observed when taking out one sheet at a time, causing a reduction in the image. It is said that toner having such a problem has poor smear property. As a method for improving the smearing property, it is effective to add a polyethylene wax to the toner (for example, Japanese Patent Application Laid-Open No. 4-313762).
Is known.

However, when the above-mentioned polypropylene wax and polyethylene wax are used in combination to simultaneously improve the offset property and the smear property, a new problem occurs that filming occurs and the fluidity and the chargeability of the toner decrease. are doing. This is because the combined use of polypropylene wax and polyethylene wax further deteriorates the compatibility between these and the binder resin,
In particular, it is considered that the polyethylene wax is liberated, and as a result, the liberated wax adheres to the photoreceptor to cause filming, and further, the fluidity and chargeability of the toner are deteriorated.
With respect to such free wax, those having a relatively large particle diameter can be removed by pulverizing and classifying, but those having a small particle diameter cannot be removed even by classification, and thus pose a more serious problem.

[0011]

DISCLOSURE OF THE INVENTION The present invention is directed to a smear property,
An object of the present invention is to provide a positively chargeable toner having excellent offset properties, filming properties, initial charge rising properties and charge stability.

[0012]

According to the present invention, (A) a binder resin containing no positive charge factor, (B) a vinyl monomer and a monomer having a quaternary salt of an amino group are polymerized in a weight ratio of 7: 3-9. : (C) vinyl monomer and amino monomer in a polymerization weight ratio of 5: 5 to 7.
The present invention relates to a polymer obtained by copolymerization at a ratio of 5: 2.5, and (D) a positively chargeable toner containing a polypropylene wax and a polyethylene wax.

The positively chargeable toner of the present invention is obtained by copolymerizing at least a vinyl monomer and a monomer whose amino group has been quaternized into a binder resin, or a copolymer of a vinyl monomer and an amino monomer. And a polypropylene wax and a polyethylene wax.

The binder resin (resin (A) in the present specification) used in the toner of the present invention does not contain a positive charge factor, that is, has a substituent such as an amino group capable of imparting positive chargeability. Absent. Specifically, styrene-acrylic copolymer resin, polyester resin, epoxy resin,
A phenol resin and the like can be exemplified, and a styrene / acrylic copolymer resin is preferable.

The styrene / acrylic copolymer resin preferably used in the present invention is a copolymer of a styrene monomer and a (meth) acrylic acid monomer. Examples of the styrene monomer include styrene, α-methylstyrene, α-ethylstyrene, α-chlorostyrene, α
-Bromostyrene, 2,5-dichlorostyrene and the like, and one or more of these can be selected and used. Examples of (meth) acrylic acid-based monomers include (meth) acrylic acid and derivatives thereof, for example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, amyl (meth) acrylate, and the like. One or more of these can be selected and used. Further, as the resin (A), two or more different resins composed of the above-mentioned monomers can be mixed and used.

The styrene / acrylic copolymer resin preferably used in the present invention is 1 to 10 KOHm
It preferably has an acid value of g / g, preferably 5 to 10 KOH mg / g. By using a styrene-acrylic copolymer resin having such an acid value as the binder resin, the effect as a positive charge inhibitor is exhibited, and an increase in charge level is prevented. Acid value is 1KOHmg / g
It is difficult to suppress the rise in the charge level below
Fog occurs. On the other hand, if it exceeds 10 KOHmg / g, the chargeability at the time of environmental change will be deteriorated. The acid value of the resin can be adjusted by appropriately adjusting the amount of (meth) acrylic acid used as the (meth) acrylic acid-based monomer. When two or more different resins are used as the binder resin, the acid value of the mixed resin may be adjusted so as to be within the above range.
In the present specification, the acid value is a value measured according to the method described in JIS K0070.

Preferred combinations of the above styrene monomer and (meth) acrylic acid monomer constituting the resin (A) include styrene, butyl acrylate and butyl methacrylate, styrene and butyl acrylate,
Examples include styrene and butyl methacrylate, styrene, butyl acrylate, butyl methacrylate, and methacrylic acid.

The resin (A) has a number average molecular weight (Mn) of 20
00 to 10,000, preferably 2500 to 7000, and the weight average molecular weight / number average molecular weight (Mw / Mn) is 2
It is desirably 0 to 90, preferably 20 to 50. In this specification, this measurement is performed by JAS as a GPC device.
CO TWINCLE HPLC, SH
Using ODEX RI SE-31 as a column with SHODE
X GPCA-80M × 2 and KF-802 were performed using tetrahydrofuran as a solvent at a flow rate of 1.2 ml / min.

The peak value of the molecular weight distribution of the resin (A) measured by the above-mentioned GPC apparatus is 5,0.
00 to 200,000, preferably 10,000 to 16
Desirably, it is in the range of 000. If the peak value is less than 5,000, the initial charge rising property is deteriorated, and the charge distribution becomes broad. On the other hand, 200,0
If it exceeds 00, the Tg of the resin increases, and the fixability decreases. The measurement conditions of the peak value are the same as the above conditions. The fixing property refers to a characteristic that the toner can be fixed on a recording material (for example, copy paper) with a fixed fixing strength without causing an offset.

The softening point (Tm) of the resin (A) is 110 to 1
30 ° C, preferably 115 to 125 ° C, and a glass transition point (Tg) of 50 to 75 ° C, preferably 55 to 70 ° C.
Is desirably within the range. Softening point of resin (A) is 1
When the temperature is lower than 10 ° C., the offset property decreases, and the temperature decreases to 130 ° C.
This is because the higher the value, the lower the fixing strength of the image.
When the glass transition point is lower than 50 ° C., the heat resistance of the toner decreases, and when it exceeds 75 ° C., the fixability decreases. When the heat resistance is reduced, the toner aggregates (blocks) at a relatively high temperature, making it difficult to smoothly supply the toner to development, causing black spots and fogging.

In the present specification, the softening point is measured by using a flow tester (CFT-500: manufactured by Shimadzu Corporation) as a measuring device, the nozzle pore diameter is 1 mm, the load is 30 kg / cm ² ,
This is the temperature at which 1.0 g of the sample flows out at a rate of 3 ° C./min. For the glass transition point, a differential scanning calorimeter (DSC-200:
(Seiko Electronics Co., Ltd.) and using alumina as a reference. 10 mg of the weighed sample was heated from normal temperature to 200 ° C. at a heating rate of 30 ° C./min, then cooled, measured at a heating rate of 10 ° C./min between 20 ° C. and 120 ° C., and the shoulder value of the main absorption peak was measured. Was taken as the glass transition point.

When two or more different resins are used as the resin (A), Mn, Mw / Mn, the peak value of the molecular weight distribution of the weight average molecular weight, Tm and Tg of the mixed resin are as described above. It is desirable to be within the range.

In the toner of the present invention, as the resin (A), the peak value of the molecular weight distribution of the styrene-acrylic copolymer resin measured by the GPC apparatus is in the range of 150,000 to 350,000. Resin and 4
It is preferable to use a resin in the range of 000 to 6000 as a mixture. The resin having the peak value in the range of 150,000 to 350,000 has Mn of 100,000 to 500,000 and Mw of 50,000.
10,000 to 1.5 million, Tg of 55 to 75 ° C, Tm of 120 to 1
More preferably, the temperature is 30 ° C. On the other hand, the resin having the peak value in the range of 4000 to 6000 has Mn of 200.
0-5000, Mw is 5000-8000, Tg is 50
More preferably, the Tm is 115 to 125 ° C. By using such a resin, both the fixing property and the offset property can be achieved.

A polymer contained in the toner of the present invention, which is obtained by copolymerizing a vinyl monomer and a monomer whose amino group has been quaternized (herein referred to as a quaternary amino monomer). Medium, referred to as polymer (B))
The monomer whose amino group has been quaternized is not particularly limited as long as it is a monomer having a quaternized amino group that can be copolymerized with a vinyl monomer described below. Formula (I);

Embedded image And methacryloyloxytrimethylammonium sulfate (MTAS).

The vinyl monomer constituting the polymer (B) is not particularly limited as long as it has a polymerizable unsaturated bond, and examples thereof include an acrylic monomer, a styrene monomer and a vinyl monomer. Can be Specifically, acrylic monomers include (meth) acrylic acid, maleic acid, itaconic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, amyl (meth) acrylate, cyclohexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate,
Behenyl (meth) acrylate, acrylamide, etc., and styrene monomers such as styrene, o, m, p
-Chlorostyrene, α-methylstyrene, vinyltoluene and the like, and as the vinyl monomer, vinyl chloride,
Vinyl acetate and the like. One or more of these are selected and used. Among these, it is preferable to use an acrylic monomer and a styrene monomer, and it is more preferable to use styrene and an alkyl (meth) acrylate. Examples of the alkyl (meth) acrylate include those having 1 to 1 carbon atoms.
8, preferably having 3 to 15 alkyl groups (meth)
It is preferred to use alkyl acrylates.

The polymerization weight ratio of the vinyl monomer and the quaternary amino chloride monomer constituting the polymer (B) is 7:
3-9: 1, preferably 7.2: 2.8-8.8: 1.
2. By using the polymer (B) having such a polymerization ratio, both excellent initial charging startability and charging stability can be achieved. If the amount of the quaternary amino chloride monomer is less than the above ratio, it is difficult for the obtained toner to maintain a sufficient charge amount, and the initial charge rising property is deteriorated, causing problems such as toner scattering. On the other hand, when the quaternary amino chloride monomer is more than the above ratio, the dispersibility of the polymer (B) in the toner is reduced, the toner charge amount is increased due to repeated use, and the frictional charging ability of the carrier to the toner is increased. Rises, and toner fog occurs in a non-image portion of the image. Further, the compatibility with the resin (A) is deteriorated, which causes a decrease in the transparency of the resin. Further, when the quaternary amino chloride monomer is more than the above ratio, the dispersibility decreases, and the blocking property deteriorates.

The method of polymerizing the vinyl monomer and the quaternary amino chloride monomer is not particularly limited, and a known radical polymerization method can be employed. Specifically, these monomers can be copolymerized by a solution polymerization method, an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, or the like. Among these polymerization methods, a solution polymerization method in which a polymerization reaction is performed in an organic solvent in the presence of an appropriate polymerization initiator is suitable. As the polymerization initiator at this time, a known initiator usually used in a radical polymerization reaction can be used, for example, azobisisobutyronitrile, benzoyl peroxide, tert-butyl perbenzoate, dicyclohexyl peroxide, Dicumyl peroxide, azobismethylbutyronitrile, azobisdimethylvaleronitrile and the like can be mentioned. At this time, the solvent to be used is not particularly limited as long as it is inert to various monomers to be used, and examples thereof include benzene, toluene, and xylene. In the method for polymerizing the polymer (B) of the present invention, since the monomers are simultaneously mixed and used as described above, the polymer (B) is considered to be a random copolymer.

The content of the polymer (B) is the same as that of the resin (A)
0.2-4.5 parts by weight, preferably 0.5-3.0 parts by weight, more preferably 0.7-2.
Desirably, it is 2 parts by weight. When the content is less than 0.2 parts by weight, the initial charge rising property of the obtained toner is deteriorated, so that a desired charge amount cannot be obtained at the time of startup, and fog tends to occur on a copied image. If the amount exceeds 4.5 parts by weight, the initial charge rising property and the charge stability tend to deteriorate, and the adhesion tends to deteriorate. When the adhesion is deteriorated, the toner easily adheres to the inner wall of the toner manufacturing apparatus, and the toner yield is reduced.

The polymer (copolymer (C) in the present specification) contained in the toner of the present invention, which is obtained by copolymerizing a vinyl monomer and an amino monomer, is quaternary. It is a monomer having an amino group that has not been salified and is not particularly limited as long as it can be copolymerized with a vinyl monomer described below.
The following general formula (II):

Embedded image (Wherein, R ₁ represents hydrogen or a methyl group, R ₂ and R ₃ each independently represent hydrogen or an alkyl group having 1 to 20 carbon atoms, X represents an oxygen atom or a nitrogen atom, and Q represents an alkylene group or an arylene group. )).

Typical examples of amino monomers include N, N
-Dimethylaminomethyl (meth) acrylate, N, N-
Diethylaminomethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-dimethylaminobutyl ( (Meth) acrylate, p-N, N-dimethylaminophenyl (meth) acrylate, p-N, N-diethylaminophenyl (meth) acrylate, p-N, N-dipropylaminophenyl (meth) acrylate, p-N, N
-Dibutylaminophenyl (meth) acrylate, p-N
-Laurylaminophenyl (meth) acrylate, p-N
-Stearylaminophenyl (meth) acrylate, p-
N, N-dimethylaminobenzyl (meth) acrylate, p
-N, N-diethylaminobenzyl (meth) acrylate, pN, N-dipropylaminobenzyl (meth) acrylate, pN, N-dibutylaminobenzyl (meth) acrylate, pN-laurylaminobenzyl (meth) ) Acrylate, p-N-stearylaminobenzyl (meth) acrylate and the like. Further, N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-diethylaminopropyl (meth) acrylamide, p- N, N-dimethylaminophenyl (meth) acrylamide, p-N, N
-Diethylaminophenyl (meth) acrylamide, p-
N, N-dipropylaminophenyl (meth) acrylamide, pN, N-dibutylaminophenyl (meth) acrylamide, pN-laurylaminophenyl (meth) acrylamide, pN-stearylaminophenyl (meth) acrylamide , PN, N-dimethylaminobenzyl (meth) acrylamide, pN, N-diethylaminobenzyl (meth) acrylamide, pN, N-dipropylaminobenzyl (meth) acrylamide, pN, N-dibutyl Examples include aminobenzyl (meth) acrylamide, pN-laurylaminobenzyl (meth) acrylamide, and pN-stearylaminobenzyl (meth) acrylamide.

The vinyl monomer constituting the polymer (C) is not particularly limited as long as it has a polymerizable unsaturated bond, and examples thereof include an acrylic monomer, a styrene monomer, and a vinyl monomer. Can be Specifically, the same monomers as the vinyl monomers constituting the polymer (B) can be exemplified.

Preferred combinations of the above amino monomers and vinyl monomers include N, N-dimethylaminoethyl (meth) acrylate and styrene, N, N
-Dimethylaminoethyl (meth) acrylate and methyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate and butyl (meth) acrylate,
N, N-dimethylaminoethyl (meth) acrylate and butyl acrylate, N, N-dimethylaminoethyl (meth) acrylate and styrene and methyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate and styrene and butyl (Meth) acrylate,
N, N-dimethylaminoethyl (meth) acrylate, styrene, butyl acrylate, and the like.

The method for polymerizing the vinyl monomer and the amino monomer is not particularly limited, and a known radical polymerization method may be employed in the same manner as the polymerization method for the polymer (B). it can. In the method for polymerizing the polymer (C), the monomers are simultaneously mixed and used, and thus the polymer (C) is considered to be a random copolymer.

The polymerization weight ratio of the vinyl monomer to the amino monomer in the polymer (C) is 5: 5 to 7.5: 2.
5, preferably 5.5: 4.5 to 7.2: 2.8. By using the polymer (C) having such a polymerization ratio, both excellent initial charging startability and charging stability can be achieved. If the amount of the amino monomer is less than the above ratio, it is difficult for the obtained toner to maintain a desired charge amount from the beginning, and the initial charge rising property is deteriorated, causing toner scattering. On the other hand, if the amino monomer content is higher than the above ratio, the toner charge increases due to repeated use, and when the obtained toner is used for a two-component developer, the frictional charging ability of the carrier with respect to the toner increases, resulting in non-image quality. Toner fog occurs in the image area. In addition, the Tg of the resin decreases, the blocking property tends to decrease, and the adhesion tends to deteriorate.

The content of the polymer (C) is the same as that of the resin (A)
It is desirable that the amount be 0.5 to 4.5 parts by weight, preferably 2 to 3.7 parts by weight, per 100 parts by weight. If the content is less than 0.5 parts by weight, the initial charging ability of the obtained toner is difficult to reach a satisfactory level. If the amount exceeds 4.5 parts by weight, charging stability is deteriorated, fog is easily generated, and heat resistance and adhesion are also easily deteriorated.

The weight average molecular weight (Mw) of the polymer (B) or the polymer (C) as described above which can be contained in the toner of the present invention measured by gel permeation chromatography (GPC) is from 5,000 to 200. 000,
Preferably, it exists in the range of 10,000 to 150,000. If the weight average molecular weight is less than 5,000, charging rises poorly and the charge distribution becomes broad, causing image noise. On the other hand, if it exceeds 200,000, the fixing property decreases due to an increase in the resin Tg.

In the positively chargeable toner of the present invention, by using the above-mentioned polymer (B) and polymer (C) in combination, it is possible to achieve both initial charge rising property and charge stability. It will be possible.

As described above, the polymer (B) and the polymer (C) are preferably contained in the resin (A) in specific amounts, respectively.
Is more preferably contained than the polymer (B). When the content of the polymer (C) is lower than that of the polymer (B), the stability of charging tends to decrease.

In the present invention, the total content of the polymer (B) and the polymer (C) is 1 to 5 parts by weight, preferably 2 to 4 parts by weight based on 100 parts by weight of the resin (A). Desirably. If the total content is less than 1 part by weight, it is difficult to reach a desired charge level. If it exceeds 5 parts by weight,
Fog is likely to occur due to deterioration of charging stability.

The polyethylene wax contained in the toner of the present invention has a softening point of 100 to 150 ° C., preferably 110 to 100 ° C., which has been conventionally effective for improving the smearing property.
145 ° C., more preferably 120-140 ° C. is used. Softening point of polyethylene wax is 100
If the temperature is lower than ℃, the heat resistance is poor, and filming is liable to occur. On the other hand, if it exceeds 150 ° C, the smearing property is reduced.
Either high-density or low-density polyethylene wax may be used, but high-density polyethylene is preferably used from the viewpoint of improving smearing properties.

As such polyethylene wax, commercially available high wax 800P (manufactured by Mitsui Chemicals, softening point;
About 140 ° C), High Wax 200P (Mitsui Chemicals,
Softening point: about 120 ° C), high wax 400P (manufactured by Mitsui Chemicals, softening point: about 135 ° C), high wax 100P
(Softening point: about 121 ° C., manufactured by Mitsui Chemicals, Inc.) can be used.

The polypropylene wax used in the present invention has been conventionally effective for improving the offset property.
Softening point is 130 to 160 ° C, preferably 140 to 155
° C, more preferably in the range of 145 to 155 ° C. When the softening point is lower than 130 ° C., not only the heat resistance decreases, but also filming easily occurs. Meanwhile, 1
If the temperature is higher than 60 ° C., the offset property decreases. By using a polypropylene wax having a softening point higher than the softening point of the polyethylene wax used in combination, preferably a polyethylene wax having a difference within 25 ° C., high-temperature offset is effectively prevented.

As such a polypropylene wax, commercially available Viscol 660P (manufactured by Sanyo Chemical Industries, softening point;
Viscole 330P (manufactured by Sanyo Chemical Co., softening point: about 152 ° C), Viscol 550P (manufactured by Sanyo Chemical Co., softening point: about 150 ° C), Viscol TS200 (manufactured by Sanyo Chemical Co., softening point: about 145) ° C) can be used.

The total content of the polyethylene wax and the polypropylene wax is 1 to 10 parts by weight, preferably 2 to 7 parts by weight, per 100 parts by weight of the resin (A). If the total content of the polyethylene wax and the polypropylene wax is less than this, the offset property and smearing property decrease, and if the total content is too large, the fluidity of the toner deteriorates and filming easily occurs. In the toner of the present invention, the total content of the polyethylene wax, the polypropylene wax, the polymer (B) and the polymer (C) is 9.5 parts by weight or less, preferably 8.5 parts by weight or less. Accordingly, a toner having excellent heat resistance and adhesion as well as smearing properties, offset properties, filming properties, initial charge rising properties and charging stability can be obtained.

Further, the content weight ratio of polypropylene wax (PP) to polyethylene wax (PE) (PP:
PE) is 20: 1 to 1:10, preferably 20: 1 to 1
It is desirable that the ratio be 1: 1, more preferably 20: 1 to 3: 1. If the content ratio by weight of the polyethylene wax is less than this, the smearing property is reduced, and if it is too large, the offset property tends to be reduced.

It is desirable that the polyethylene wax and the polypropylene wax are contained in such a manner that the total content and the content weight ratio are within the above ranges, but the polyethylene wax is used in an amount of 0.1 to 100 parts by weight of the resin (A). 1 to 5 parts by weight, preferably 0.3 to 4.5 parts by weight, more preferably 0.5 to 3 parts by weight, and the polypropylene wax is 1 to 10 parts by weight based on 100 parts by weight of the resin (A).
More preferably, the content is 1.5 parts by weight, preferably 1.5 to 7 parts by weight, more preferably 3 to 5 parts by weight.

Further, the colorant, magnetic powder, fluidizing agent and cleaning agent commonly used in toners can be appropriately added to the toner of the present invention.

The colorant used in the toner of the present invention is not particularly limited, and a colorant conventionally used in electrophotography can be used, and examples thereof include the following. Black pigments include carbon black, copper oxide,
Manganese dioxide, aniline black, activated carbon, ferrite, magnetite and the like can be used. As a yellow pigment, graphite, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navels yellow, naphthol yellow S,
Bunzer Yellow G, Bunzer Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake, and the like can be used.

Examples of the red pigment include red lead, molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, indaslen brilliant orange RK, benzidine orange G, indaslen brilliant orange GK, bengala, cadmium red, red lead, permanent Red 4R, Risor Red,
Pyrazolone red, watching red, lake red C, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, alizarin lake,
Brilliant Carmine 3B, permanent orange GT
R, Vulcan Fast Orange GG, Permanent Red F4RH, Permanent Carmine FB and the like can be used. Blue pigments include navy blue, cobalt blue, alkaline blue lake, Victoria blue lake,
Phthalocyanine blue or the like can be used. The content of these coloring agents is not particularly limited, either,
Usually, the amount is 1 to 20 parts by weight, preferably 3 to 15 parts by weight based on 100 parts by weight of the resin (A).

As the magnetic powder, iron powder, iron oxide powder, ferrite, nickel and the like can be used.

When a fluidizing agent is used, silica fine particles, titanium dioxide fine particles, amylna fine particles, magnesium fluoride fine particles, silicon carbide fine particles, boron carbide fine particles, titanium carbide fine particles, zirconium carbide fine particles, boron nitride fine particles, titanium nitride fine particles. , Zirconium nitride fine particles, magnetite fine particles, molybdenum disulfide fine particles,
Fine particles of aluminum stearate, fine particles of magnesium stearate, fine particles of zinc stearate and the like can be used. It is desirable that these fine particles are used after being subjected to a hydrophobic treatment with a silane coupling agent, a titanium coupling agent, a higher fatty acid, silicone oil, or the like. The amount of the fluidizing agent is 0.05 to 100 parts by weight of the toner.
It is desirable to use 5 parts by weight, preferably 0.1 to 3 parts by weight.

As a cleaning agent, styrene, acrylic, methacrylic, benzoguanamine, silicone, Teflon, polyethylene, etc. granulated by a wet polymerization method such as emulsion polymerization, soap-free emulsion polymerization, non-aqueous dispersion polymerization or a gas phase method. And various organic fine particles such as polypropylene can be used alone or in combination.

The toner of the present invention can be prepared by a conventionally known method, for example, in addition to the above resin (A), polymer (B), polymer (C), polypropylene wax and polyethylene wax, It is obtained by adding a predetermined amount of other desired additives, mixing, melting and kneading, and then pulverizing and classifying.

It is preferable that the volume average particle diameter of the toner of the present invention thus obtained is controlled to 6 to 10 μm, preferably 7 to 9 μm.

The positively chargeable toner of the present invention thus obtained is excellent in smear property, offset property, filming property, initial charge rising property and charge stability. When the toner of the present invention is used, noises such as fogging and filming hardly occur on a copied image. Further, in the present invention, by adjusting the contents of the polyethylene wax, the polypropylene wax, the polymer (B) and the polymer (C), a toner having more excellent heat resistance and adhesion can be provided.

The toner of the present invention can be used in either a one-component developer without using a carrier or a two-component developer used with a carrier, but is preferably used as a two-component developer. As the carrier used with the toner of the present invention, known carriers can be used, for example, iron powder, a carrier composed of magnetic particles such as ferrite, a coated carrier in which the surface of the magnetic particles is coated with a coating agent such as a resin, Alternatively, any of a dispersion type carrier obtained by dispersing a magnetic fine powder in a binder resin can be used. As such a carrier, those having a volume average particle size of 15 to 100 μm, preferably 20 to 80 μm are suitable. A preferred carrier in the present invention is a carrier having a charge point for the toner, that is, a negatively chargeable resin present on the surface. Such resins include polyester resins, polyolefin resins such as polyethylene,
Examples include a fluoropolymer resin such as a homopolymer of a fluorovinyl monomer such as tetrafluoroethylene and vinylidene fluoride or a copolymer with another vinyl monomer.
In particular, a carrier in which a polyolefin-based resin coating layer is formed by directly polymerizing an olefin monomer on the surface of a magnetic particle, or a carrier obtained by dispersing a magnetic substance fine powder in a polyester resin is used in combination with the toner of the present invention. It is preferable from the viewpoint of chargeability. The following examples illustrate the invention in more detail.

[0057]

EXAMPLES (Production of polymers B1 to B5) 1 liter of 4
In a lip joint, 85 parts by weight of styrene (ST), 10 parts by weight of butyl methacrylate (BMA), the above-mentioned general formula (I)
5 parts by weight of methacryloyloxytrimethylammonium sulfate (MTAS), 50 parts by weight of toluene and azobisisobutyronitrile (AIBN)
After adding and dissolving 0.5 part by weight, under a nitrogen stream, 80 parts by weight were added.
The reaction was carried out at a temperature of 6 ° C. for 6 hours to effect polymerization. Next, after distilling off toluene, the pressure was reduced to 40 to 50 mmHg at 180 to 190 ° C to completely remove volatile components. The obtained polymer was a colorless and transparent solid having a glass transition point (Tg) of 67 ° C. and a weight average molecular weight (Mw) of 45,000, and was designated as Polymer B1. Also, polymers B2 to B5 were obtained in the same manner as in the method for producing polymer B1, except that the compounds shown in Table 1 were used in the amounts indicated. These Tg and M
Table 1 summarizes w. In addition, Mw was measured by gel permeation chromatography (GPC).

[0058]

[Table 1]

(Production of Polymers C1 to C5) 90 parts by weight of styrene (ST), 10 parts by weight of dimethylaminoethyl methacrylate (DAM), 50 parts by weight of toluene and azobisisobutyro were added to a 1-liter four-necked corben. After adding and dissolving 0.5 part by weight of nitrile (AIBN),
The reaction was carried out at 80 ° C. for 6 hours in a nitrogen stream to carry out polymerization.
Next, after distilling off toluene, 40-180 ° C.
The pressure was reduced to ５０50 mmHg, and the volatile components were completely removed.
The obtained polymer is a colorless and transparent solid and has a glass transition point (T
g) The polymer had a weight average molecular weight (Mw) of 60,000 at 72 ° C., and this polymer was designated as polymer C1. Also, polymers C2 to C5 were obtained in the same manner as in the method for producing polymer C1, except that the compounds shown in Table 2 were used in the amounts indicated. Table 2 summarizes these Tg and Mw. Note that Mw
Was measured by gel permeation chromatography (GPC).

[0060]

[Table 2]

Example 1 parts by weight styrene-butyl acrylate-butyl methacrylate copolymer resin 50 (polymerization weight ratio 65:10:25, molecular weight distribution peak value = 4500) styrene-butyl acrylate-butyl methacrylate -Methacrylic acid copolymer resin 50 (polymerization weight ratio 60: 10: 28: 2, molecular weight distribution peak value = 150,000)-carbon black (REGAL330; manufactured by Cabot Corporation) 7-polypropylene wax (PP) 3.5 (Viscol 660P) 1. Polyethylene wax (PE) 0.5 (high wax 800P; softening point 140 ° C., manufactured by Mitsui Chemicals, Inc.)-The above polymer B3 1.0-The above polymer C3 5 ・ Magnetic powder (magnetite BR-605; manufactured by Titanium Industry Co., Ltd.) 2 After thoroughly mixed in a mixer, 2
The mixture was kneaded with a screw extruder and cooled. Next, the kneaded material was coarsely pulverized, further finely pulverized by a jet pulverizer, and classified by an air classifier to obtain toner particles having a volume average particle diameter of 8 μm. To 100 parts by weight of the obtained toner particles, 0.2 part by weight of hydrophobic silica (R974; manufactured by Nippon Aerosil Co., Ltd.) was externally added and mixed to obtain a toner.

Examples 2 to 15 and Comparative Examples 1 to 11 In each of Examples and Comparative Examples, the indicated polymers B and C, polypropylene wax (PP) and polyethylene wax (PE) were used in the indicated amounts. A toner was obtained in the same manner as in Example 1, except that the toner was used.

[0063]

[Table 3]

[0064]

[Table 4]

The toners obtained in the above Examples and Comparative Examples were evaluated for smearing properties, offset properties, filming properties, initial charging rise properties, charging stability, heat resistance (blocking properties), and the like according to the following evaluation methods. Each property of adhesiveness was evaluated. The results are summarized in Tables 3 and 4. In the following evaluations, a developer obtained by mixing a toner with a carrier described below at a weight ratio (toner / carrier) of 5/95 was used.

[Evaluation Method] (1) Smear Property After the developer was fixed on the copy paper using a copying machine (EP4050: manufactured by Minolta Co.), another unused copy paper was copied first. Rub together with the paper on which the image was formed,
The degree of dirt on the unused copy paper was observed and ranked as follows. ：: Almost no stain was noticeable. Δ: Stain was slightly observed, but there was no practical problem. ×: Stain was observed on all paper surfaces.

(2) Offset Property When copying using the above-mentioned copying machine modified so as to be able to change the fixing roller temperature, the fixing roller temperature is raised to around 240 ° C., and the following occurs depending on the temperature at which the offset occurs. Ranking was performed. ：: no offset occurred below 240 ° C. Δ: Offset did not occur below 230 ° C. X: Offset occurred below 220 ° C.

(3) Filming Property After continuously copying 50,000 sheets using the above copying machine (EP4050: manufactured by Minolta), a halftone image was formed and the photosensitive member was observed. Was ranked. The fixing roller temperature was 190 ° C. ：: Neither image stain nor toner component adhesion to the photoreceptor was observed. Δ: Part of the surface of the photoreceptor was slightly hazy, but there was no image disturbance. ×: The entire photoconductor was cloudy, and the image was further disturbed.

(4) Initial Charge Rising Property 30 g of the developer was placed in a 50 cc plastic bottle. The charge amount (μC / g) of the toner was measured after 3 minutes, 10 minutes, and 30 minutes after placing the poly bottle on a gantry rotating at 120 rpm, and ranked as follows. ：: The charge amount reached the saturation region in 3 minutes. Δ: The charge amount reached the saturation region in 10 minutes. ×: The charge amount was not saturated even after 30 minutes, and the charge was still increased and was not stable.

In measuring the charge amount, 1 g of the developer measured by a precision balance was placed on the entire surface of the conductive sleeve (1) of the charge amount measuring device shown in FIG. The rotation speed of the magnet roll (2) provided in the conductive sleeve (1) was set to 100 rpm. Then, a bias voltage of 2 KV was applied from the bias power source (3) to the same polarity as the charged potential of the toner, and the potential Vm at the cylindrical electrode (4) was read and attached to the cylindrical electrode (4) from the conductive sleeve (1). The weight of the toner is measured with a precision balance, and the average charge amount (μ
C / g).

(5) Charge Stability The developer was loaded into a copying machine (EP 9765: manufactured by Minolta), and the toner charge amount after copying after 1000 and 10,000 sheets was measured. The change in charge amount was ranked as follows. The charge amount was measured using the charge amount measuring device shown in FIG. 1 in the same manner as described above. ：: The fluctuation width of the charge amount was less than 3 μC / g. Δ: The fluctuation of the charge amount was 3 μC / g or more and less than 5 μC / g. X: The fluctuation width of the charge amount was 5 μC / g or more.

(6) Heat Resistance (Blocking Property) After leaving 10 g of the toner at a high temperature of 50 ° C. for 24 hours,
This was performed by visually confirming the toner. ：: No aggregate was observed. Δ: Less than 10 aggregates were observed. ×: 10 or more aggregates were observed.

(7) Adhesion In producing a toner as a trial, the amount of toner adhering to each device was calculated from the input amount and the total recovered amount. ：: The adhesion amount was less than 5% of the input amount. Δ: The adhesion amount was less than 10% of the input amount. X: The adhesion amount was 10% or more of the input amount.

(Manufacture of Carrier) Carriers used for evaluating the toners of Examples and Comparative Examples were manufactured as follows. Carrier compounding component: 100 parts by weight of polyester resin (number average molecular weight: 5000, weight average molecular weight: 115000, glass transition point: 67 ° C., softening point: 123 ° C.) 500 parts by weight of ferrite fine particles (MFP-2, manufactured by TDK Corporation) dispersion 3 parts by weight of colloidal silica (Aerosil # 200, manufactured by Nippon Aerosil Co., Ltd.) After thoroughly mixing the above ingredients with a Henschel mixer,
After melt-kneading with a twin-screw extruder, cooling, coarse pulverization, fine pulverization with a jet mill, and classification using an air classifier, a volume average particle size of 60 μm, and an electric resistance value of 5.
A dispersion type carrier of 8 × 10 ¹³ Ω · cm was obtained.

[0075]

As can be seen from the examples and comparative examples,
The positively chargeable toner of the present invention exhibits excellent smearing property, offset property, filming property, initial charge rising property and charge stability, and fog and filming hardly occur on a copied image even after printing a large number of sheets. Further, by adjusting the contents of the polyethylene wax, the polypropylene wax, the polymer (B) and the polymer (C), it is possible to provide a toner further excellent in heat resistance and adhesion.

[Brief description of the drawings]

FIG. 1 is a charge amount measuring device.

[Explanation of symbols]

1: conductive sleeve, 2: magnet roll, 3: bias power supply, 4: cylindrical electrode.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Yoshikazu Nishihara 2-3-13 Azuchicho, Chuo-ku, Osaka-shi, Osaka Inside Osaka International Building Minolta Co., Ltd. (72) Hiroyuki Fukuda Azuchi-cho, Chuo-ku, Osaka-shi, Osaka 2-3-13 Osaka International Building Minolta Co., Ltd. F-term (reference) 2H005 AA01 AA06 CA04 CA13 CA14 CA28 DA03 DA06 EA03 EA07 EA10

Claims (6)

[Claims] (A) a binder resin containing no positive charge factor; and (B) a vinyl monomer and a monomer obtained by quaternary salification of an amino group are copolymerized in a polymerization weight ratio of 7: 3 to 9: 1. (C) a polymer obtained by copolymerizing a vinyl monomer and an amino monomer at a polymerization weight ratio of 5: 5 to 7.5: 2.5; and (D) a polymer comprising a polypropylene wax and a polyethylene wax. Chargeable toner. 2. The positively chargeable toner according to claim 1, wherein the content ratio by weight of the polypropylene wax to the polyethylene wax is from 20: 1 to 1:10. 3. The positively chargeable toner according to claim 1, wherein the content weight ratio of the polypropylene wax to the polyethylene wax is 20: 1 to 3: 1. 4. A polypropylene wax having a softening point of 13
0 ° C to 160 ° C, the softening point of polyethylene wax is 10
The positively chargeable toner according to any one of claims 1 to 3, wherein the temperature is 0 to 150 ° C, and the softening point of the polypropylene wax is higher than the softening point of the polyethylene wax. 5. The positive chargeability according to claim 1, wherein the binder resin (A) is a styrene / acrylic copolymer resin and has an acid value of 1 to 10 KOHmg / g. toner. 6. The total content of the polymer (B) and the polymer (C) is 1 to 5 parts by weight based on 100 parts by weight of the resin (A), and the content of the polymer (C) is heavy. The positively chargeable toner according to any one of claims 1 to 5, wherein the content of the toner is larger than the content of the united toner (B).