A positively-chargeable toner includes a binder resin, a coloring agent, and a quaternary-ammonium-base containing copolymer with a weight-average molecular weight of 5,000 to 25,000, which included a repeat unit of formula (I), and a repeat unit of formula (II): ##STR1## wherein R.sup.1 is a hydrogen atom or a methyl group; R.sup.2 is a hydrogen atom or a methyl group; R.sup.3 is an alkylene group, and R.sup.4, R.sup.5 and R.sup.6 are an alkyl group. The quaternary-ammonium-base containing copolymer may further include a repeat unit of formula (III): ##STR2## wherein R.sup.7 is a hydrogen atom or a methyl group; and R.sup.8 is an alkyl group.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a positively chargeable toner for use in 
electrophotography. 
2. Discussion of Background 
Varieties of electrophotographic methods have been disclosed, for example, 
in U.S. Pat. No. 2,297,691 and Japanese Patent Publications 49-23910 and 
43-24748. Generally, such electrophotographic methods are capable of 
providing copies of images by the following steps: Electrostatic latent 
images are formed on a photoconductor which comprises an 
electrophotographic material by a variety of methods, the electrostatic 
latent images are developed to visible toner images with toner, and the 
visible toner images are transferred to a transfer sheet such as a sheet 
of paper and fixed thereto by the application of heat and/or pressure 
thereto, whereby copies of the images are obtained. 
The methods of developing such electrostatic latent images can be roughly 
classified into a liquid development method and a dry development method. 
In the liquid development method, there is employed a liquid developer in 
which finely-divided particles of a variety of pigments or dyes are 
dispersed in an insulating organic solvent. 
In the dry development method, a toner comprising a natural or synthetic 
resin and a coloring agent, such as carbon black, which is dispersed in 
the resin, is employed, for example, as in the conventionally known 
cascade method, magnetic brush method and powder cloud method. A specific 
example of the dry development method is a method using a two-component 
dry developer. 
Such a two-component dry developer comprises relatively large carrier 
particles and small toner particles which are held on the surface of the 
carrier particles by the electrostatic force generated by the friction 
between the carrier particles and the toner particles. 
When such a two-component dry developer is brought near electrostatic 
latent images, the toner particles are attracted to the electrostatic 
latent images by the electric field formed by the electrostatic latent 
images and are caused to be deposited on the electrostatic latent images, 
with the bonding force between the toner particles and the carrier 
particles being overcome by the electrostatic attraction between the toner 
particles and the electrostatic latent images, so that the electrostatic 
latent images are developed to visible toner images. 
Therefore, it is required that the carrier particles be capable of 
triboelectrically charging toner particles to the desired polarity with a 
sufficiently large charge quantity for developing electrostatic latent 
images for an extended period of time for use in practice. 
However, in the case of conventional developers, a toner film is formed on 
the surface of carrier particles while in use by the mechanical collision 
between the toner particles and the carrier particles or between these 
particles and parts of a development unit, for example, in a copying 
machine, and/or by the heat generated by the above-mentioned mechanical 
collision. 
The phenomenon that such a toner film is formed on the surface of carrier 
particles while in use is generally referred to as "spent phenomenon". 
Once such a spent phenomenon takes place in the developer, the charging 
characteristics of the carrier particles are significantly degraded with 
time while in use, so that it is required that the developer be replaced 
with a new developer in its entirety. 
Various methods of preventing the occurrence of such a spent phenomenon 
have been conventionally proposed by coating the surface of carrier 
particles with a variety of resins. 
In one of such conventional methods, a silicone resin is coated on the 
surface of carrier particles to prevent the occurrence of the spent 
phenomenon. This method, however, has the shortcoming that the 
silicone-resin-coated carrier particles cannot triboelectrically charge 
toner particles sufficiently for use in practice. 
In order to triboelectrically charge toner sufficiently, there are 
conventionally known, for example, a method of utilizing the triboelectric 
charging properties of a binder resin which is employed as the main 
component of the toner, and a method of adding a charge-imparting agent to 
the toner. 
Specific examples of a positive charge imparting agent which are used in 
practice are Nigrosine dyes as disclosed in Japanese Patent Publication 
41-2427, and quaternary ammonium salts as disclosed in U.S. Pat. No. 
3,565,654, and Japanese Laid-Open Patent Application 60-169857. 
Furthermore, Japanese Patent Publication 59-9906 discloses a positively 
chargeable toner comprising a laked xanthene dye. 
Conventional positive-charge imparting agents have the shortcoming that the 
charge quantity of the developer in which the positive-charge imparting 
agents are employed is largely changed depending upon the ambient 
conditions. 
Recently it is required that the particle size of toner be significantly 
reduced in accordance with the demand for fine toner images with high 
quality. For producing such finely-divided toner particles, it is required 
that a charge-imparting agent be extremely uniformly dispersed in each 
toner particle. Conventional charge imparting agents, however, cannot meet 
this requirement, so that improper deposition of toner particles on the 
background of images, and scattering of toner particles occur when used in 
practice. 
A quaternary ammonium salt disclosed in Japanese Laid-Open Patent 
Application 63-60458 is a charge imparting agent which is improved with 
respect to most of the above-mentioned shortcomings of the conventional 
charge imparting agents. 
This charge imparting agent, however, cannot solve the conventional 
problems sufficiently when used in combination with a developer which 
comprises silicone resin coated carrier particles and extremely 
finely-divided toner particles, so that the toner deposition on the 
background of images and scattering of the toner particles still occur 
when the charge imparting agent is employed. 
SUMMARY OF THE INVENTION 
It is therefore an object of the present invention to provide a toner which 
can be positively charged sufficiently without causing the problems of the 
deposition thereof on the background of developed toner images and 
improper scattering thereof while in use even when the toner is used in 
combination with carrier particles which are coated with a silicone-resin 
for the prevention of the so-called spent phenomenon. 
This object of the present invention can be achieved by a 
positively-chargeable toner which comprises (a) a binder resin, (b) a 
coloring agent, and (c) a quaternary-ammonium-base containing copolymer 
with a weight-average molecular weight of 5,000 to 25,000, comprising a 
repeat unit of formula (I) in an amount by weight of 98.0 to 99.5, and a 
repeat unit of formula (II) in an amount by weight of 2.0 to 0.5, when the 
total amount by weight of the repeat unit of formula (I) and the repeat 
unit of formula (II) is 100: 
##STR3## 
wherein R.sup.1 is a hydrogen atom or a methyl group; R.sup.2 is a 
hydrogen atom or a methyl group; R.sup.3 is an alkylene group, preferably 
with 1 to 12 carbon atoms, and R.sup.4, R.sup.5 and R.sup.6 are an alkyl 
group, preferably with 1 to 12 carbon atoms. 
The above object of the present invention can also be achieved by a 
positively-chargeable toner which comprises (a) a binder resin, (b) a 
coloring agent, and (c) a quaternary-ammonium-base containing copolymer 
with a weight-average molecular weight of 5,000 to 25,000, comprising a 
repeat unit of formula (I) in an amount by weight of 98.5 to 63.0, a 
repeat unit of formula (II) in an amount by weight of 2.0 to 0.5, and a 
repeat unit of formula (III) in an amount by weight of 35.0 to 1.0 when 
the total amount by weight of the repeat unit of formula (I), the repeat 
unit of formula (II), and the repeat unit of formula (III) is 100: 
##STR4## 
wherein R.sup.1, R.sup.2 and R.sup.7 are independently a hydrogen atom or 
a methyl group; R.sup.3 is an alkylene group, preferably with 1 to 12 
carbon atoms, and R.sup.4, R.sup.5, R.sup.6 and R.sup.8 are an alkyl 
group, which may be the same or different, preferably with 1 to 12 carbon 
atoms. 
For the object of the present invention, any of the above-mentioned toners 
in which as the binder agent, a binder resin which contains 50 wt. % or 
more of polyester resin is used, with the softening point of the toner 
being 85.degree. C. or less, may be employed. 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
As the binder resin for use in the toner of the present invention, for 
example, the following conventionally known binder resins can be employed: 
Styrene resins, that is, homopolymers and copolymers of styrene or 
substituted styrene derivatives, such as polystyrene, 
poly-.alpha.-methylstyrene, styrene-chloro-styrene copolymer, 
styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl 
chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid 
copolymer, styrene-acrylic ester copolymer (for example, styrene-methyl 
acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl 
acrylate copolymer, styrene-octyl acrylate copolymer, and styrene-phenyl 
acrylate copolymer), styrene-methacrylic ester copolymer (for example, 
styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate 
copolymer, styrene-butyl methacrylate copolymer, styrene-phenyl 
methacrylate copolymer), styrene-methyl .alpha.-methyl chloroacrylate 
copolymer, styrene-acrylonitrile-acrylic ester copolymer; vinyl chloride 
resin; rosin-modified maleic acid resin, phenol resin; epoxy resin; 
polyester resin; low-molecular-weight polypropylene; ionomer resin; 
polyurethane resin; ketone resin; ethylene-ethyl acrylate copolymer; 
xylene resin; and polyvinyl butylate resin. These resins can be used alone 
or in combination. 
There is no particular limitation on the method of producing these resins, 
and any polymerization methods such as bulk poylmerization, solution 
polymerization, emulsion polymerization, and suspension polymerization can 
be employed. 
As mentioned previously, according to the present invention, a binder resin 
which contains 50 wt. % or more of polyester resin may be used. 
As the polyester resin used for the above-mentioned binder resin, it is 
preferable to use a polyester resin having a glass transition point Tg in 
the range of 65.degree. to 75.degree. C. When the content of the polyester 
resin is 50 wt. % or more, a toner with a softening point of 85.degree. C. 
or less having low temperature image fixing performance and excellent 
preservability can be obtained. 
Examples of the coloring agent for use in the toner of the present 
invention are carbon black, lamp black, iron black, aniline blue, 
Phthalocyanine blue, Ultramarine Blue, phthalocyanine Green, Malachite 
Green Oxalate, chrome yellow, Quinoline Yellow, Benzidine Yellow, 
Quinacridone, Rose Bengal, and triarylmethane dye. Any conventional dyes 
and pigments can be used alone or in combination. It is preferable that 
the amount of such a coloring agent be in the range of 1 to 30 parts by 
weight, more preferably in the range of 3 to 20 parts by weight, to 100 
parts by weight of the binder resin. 
The toner according to the present invention may further comprise a 
fluidity-improving agent such as finely-divided inorganic particles. 
Specific examples of the finely-divided inorganic particles are particles 
of silica, alumina, titanium oxide, barium titanate, magnesium titanate, 
calcium titanate, strontium titanate, zinc oxide, magnesium oxide, 
zirconium oxide, calcium carbonate, silicon carbide, and silicon nitride. 
These inorganic particles can be used alone or in combination. It is 
preferable that the amount of these fluidity-improving agents be in the 
range of 0.1 to 2.0 parts by weight, more preferably in the range of 0.2 
to 1.5 parts by weight, to 100 parts by weight of the toner. 
The toner of the present invention may further comprises a releasing agent 
such as a wax component when necessary. Specific examples of such a wax 
component include polyolefin waxes such as polyethylene wax and 
polypropylene wax, and natural waxes such as carnauba wax, candelilla wax, 
and rice wax. 
A first type quaternary-ammonium-base containing copolymer for use in the 
toner of the present invention has a weight-average molecular weight of 
5,000 to 25,000, and comprises a repeat unit of formula (I) in an amount 
by weight of 98.0 to 99.5, and repeat unit of formula (II) in an amount by 
weight of 2.0 to 0.5, when the total amount by weight of the repeat unit 
of formula (I) and the repeat unit of formula (II) is 100 (hereinafter, 
the amount ratio of the repeat unit of formula (I) is referred to as 98.0 
to 99.5 wt. %, and the amount ratio of the repeat unit of formula (II) is 
referred to as 2.0 to 0,5 wt. %): 
##STR5## 
wherein R.sup.1 is a hydrogen atom or an methyl group; R.sup.2 is a 
hydrogen atom or a methyl group; R.sup.3 is an alkylene group, preferably 
with 1 to 12 carbon atoms, and R.sup.4, R.sup.5 and R.sup.6 are an alkyl 
group, preferably with 1 to 12 carbon atoms. 
In the above-mentioned first type quaternary-ammonium-bass containing 
copolymer for use in the toner of the present invention, the amount ratio 
of the repeat unit of formula (I) to the repeat unit of formula (II) is 
important. 
This first type quaternary-ammonium-base containing copolymer is superior 
in the dispersibility in binder resins to conventional charge-imparting 
agents. However, the charge-imparting effect of the first type 
quaternary-ammonium-base containing copolymer is so extremely strong that 
when the amount ratio of the repeat unit of formula (II) exceeds 2.0 wt. 
%, the amount of the quaternary-ammonium base containing copolymer to be 
added to the toner must be decreased to an extremely small amount in order 
to maintain the charge quantity of the toner appropriately. As a result, 
when high dispersibility is required as in the case of an 
extremely-small-particle size toner, the amount of the quaternary-ammonium 
base containing copolymer is insufficient, so that the deposition of the 
toner particles on the background of toner images and the scattering of 
the toner particles are apt to occur. For these reasons, it is important 
that the amount ratio of the repeat unit of formula (II) is set in the 
range of 0.5 wt. % as stated above, whereby the objects of the present 
invention can be achieved. In other words, when the above-mentioned first 
type quaternary-ammonium base containing copolymer is employed, the charge 
imparting effect is appropriately controlled, so that the amount of the 
quaternary-ammonium base containing copolymer in the toner is appropriate, 
whereby toner with excellent charging characteristics can be obtained. 
When the amount of the repeat unit of formula (II) is less than 0.5 wt. %, 
a large amount of the quaternary-ammonium base containing copolymer must 
be added to the toner. The addition of a large amount of the 
quaternary-ammonium base containing copolymer has adverse effects on the 
thermal characteristics of the binder resin contained in the toner. 
As mentioned previously, it is required that the first type 
quaternary-ammonium-base containing copolymer for use in the toner of the 
present invention have a weight-average molecular weight of 5,000 to 
25,000. 
When the weight-average molecular weight is less than 5,000, the mechanical 
strength of the quaternary-ammonium-base containing copolymer is reduced, 
and accordingly, the mechanical strength of the toner is also reduced. As 
a result, it occurs that the toner particles are destroyed while in use 
within a copying machine. The thus destroyed toner particles are apt to 
adhere to the surface of carrier particles, so that the so-called spent 
phenomenon takes place and therefore the life of the developer is 
significantly shortened. 
When the weight-average molecular weight exceeds 25,000, the compatibility 
of the quaternary-ammonium-base containing copolymer with the binder resin 
for the toner is reduced, so that the dispersion of the 
quaternary-ammonium-base containing copolymer in the binder resin becomes 
improper. This causes the deposition of toner particles on the background 
of toner images and the scattering of the toner particles. 
A second type quaternary-ammonium-base containing copolymer for use in the 
toner of the present invention has a weight-average molecular weight of 
5,000 to 25,000, and comprises a repeat unit of formula (I) in an amount 
by weight of 98.5 to 63.0, a repeat unit of formula (II) in an amount by 
weight of 2.0 to 0.5, and a repeat unit of formula (III) in an amount by 
weight of 35.0 to 1.0, when the total amount by weight of the repeat unit 
of formula (I), the repeat unit of formula (II) and the repeat unit of 
formula (III) is 100 (hereinafter, the amount ratio of the repeat unit of 
formula (I) is referred to as 98.5 to 63.0 wt. %, the amount ratio of the 
repeat unit of formula (II) is referred to as 2.0 to 0.5 wt. %, and the 
amount ratio of the repeat unit of formula (III) is referred to as 35.0 to 
1.0 wt. %): 
##STR6## 
wherein R.sup.1, R.sup.2 and R.sup.7 are independently a hydrogen atom or 
a methyl group; R.sup.3 is an alkylene group, preferably with 1 to 12 
carbon atoms, and R.sup.4, R.sup.5, R.sup.6 and R.sup.8 are an alkyl 
group, which may be the same or different, preferably with 1 to 12 carbon 
atoms. 
In the above-mentioned second type quaternary-ammonium-base containing 
copolymer for use in the toner of the present invention, the amount ratio 
of the repeat unit of formula (I) to the repeat unit of formula (II) is 
important. 
This second type quaternary-ammonium-base containing copolymer is superior 
in the dispersibility in binder resins to conventional charge-imparting 
agents. However, the charge-imparting effect of the second type 
quaternary-ammonium-base containing copolymer is so extremely strong that 
when the amount ratio of the repeat unit of formula (II) exceeds 2.0 wt. 
%, the amount of the quaternary-ammonium base containing copolymer to be 
added to the toner must be decreased to a small amount in order to 
maintain the charge quantity of the toner appropriately. As a result, when 
high dispersibility is required as in the case of an 
extremely-small-particle size toner, the amount of the quaternary-ammonium 
base containing copolymer is insufficient, so that the deposition of toner 
particles on the background of toner images and the scattering of the 
toner particles are apt to occur. For these reasons, it is important that 
the amount ratio of the repeat unit of formula (II) is set in the range of 
0.5 to 2.0 wt. % as stated above, whereby the objects of the present 
invention can be achieved. In other words, when the above-mentioned second 
type quaternary-ammonium base containing copolymer is employed, a toner 
with excellent charging characteristics can be obtained. 
When the amount of the repeat unit of formula (II) is less than 0.5 wt. %, 
a large amount of the quaternary-ammonium base containing copolymer must 
be added to the toner. The addition of a large amount of the 
quaternary-ammonium base containing copolymer has adverse effects on the 
thermal characteristics of the binder resin contained in the toner. 
The repeat unit of formula (III) contained in the quaternary ammonium base 
containing copolymer has the functions of appropriately decreasing the 
melting viscosity of the quaternary-ammonium-base containing copolymer, 
and significantly improving the dispersion of the quaternary-ammonium-base 
containing copolymer in the binder resin. 
As mentioned previously, it is required that the second type 
quaternary-ammonium-base containing copolymer for use in the toner of the 
present invention have a weight-average molecular weight of 5,000 to 
25,000. 
When the weight-average molecular weight is less than 5,000, the mechanical 
strength of the quaternary-ammonium-base containing copolymer is reduced, 
and accordingly, the mechanical strength of the toner is also reduced. As 
a result, it occurs that the toner particles are destroyed while in use 
within a copying machine. The thus destroyed toner particles are apt to 
adhere to the surface of carrier particles, so that the so-called spent 
phenomenon takes place and therefore the life of the developer is 
significantly shortened. 
When the weight-average molecular weight exceeds 25,000, the compatibility 
of the quaternary-ammonium-base containing copolymer with the binder resin 
for the toner is reduced, so that dispersion of the 
quaternary-ammonium-base containing copolymer in the binder resin becomes 
improper. This causes the deposition of toner particles on the background 
of toner images and the scattering of the toner particles. 
As the carrier for use with the toner of the present invention, it is 
preferable to use a carrier with the surface thereof being coated with 
silicone resin. Silicone resin has a very small surface energy so that it 
has a significant effect of preventing the spent phenomenon, but its toner 
charging performance is extremely low. 
A developer comprising the toner of the present invention which contains 
the quaternary-ammonium-base containing copolymer exhibits excellent 
charging performance and therefore a two-component developer, which is 
free from the problems of toner deposition on the background of images, 
the scattering of toner, and the spent phenomenon, and has a long life, 
can be provided when the toner of the present invention is employed. 
It is preferable that the amount of the quaternary-ammonium-base containing 
copolymer be in the range of 0.2 to 5.0 parts by weight, to 100 parts by 
weight of the toner. 
The toner of the present invention can be prepared by kneading and fusing 
(a) a binder resin, (b) a coloring agent, (c) a first type or second type 
quaternary-ammonium-base containing copolymer with a weight-average 
molecular weight of 5,000 to 25,000, and other components such wax when 
necessary, in a kneader such as an extruder, cooling the kneaded mixture 
thereof to solidify the same, pulverizing the solidified mixture, and 
classifying the pulverized mixture to obtain finely-divided particles with 
a volume mean diameter in the range of 5 to 10 .mu.m which are used as the 
toner of the present invention. 
As mentioned previously, as the carrier for use with the toner of the 
present invention, a silicone-resin-coated carrier is most useful. As the 
silicone resin for the carrier, any conventional silicone resins can be 
employed. For example, an ordinary temperature curing type silicone resin 
of the following formula (IV) can be employed: 
##STR7## 
wherein R is a hydrogen atom, a halogen atom, a hydroxyl group, a methoxy 
group, an alkyl group having 1 to 4 carbon atoms, or a phenyl group. 
As the core material for the carrier particles, conventionally employed 
metals, alloys and non-metal materials, such as cobalt, iron, copper, 
nickel, zinc, aluminum, brass, and glass, can be employed. 
The silicone resin can be coated on such a core material by a conventional 
coating method such as spray coating which is conducted by dissolving the 
silicone resin in a solvent and spraying the solution on the surface of 
the core material. 
It is preferable that the carrier and the toner of the present invention be 
mixed in such a ration that the toner particles covers 30 to 90% of the 
entire surface of each carrier particle.

Other features of this invention will become apparent in the course of the 
following description of exemplary embodiments, which are given for 
illustration of the invention and are not intended to be limiting thereof. 
EXAMPLE 1 
[Preparation of Toner No. 1] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 11 .mu.m were obtained: 
______________________________________ 
Parts by 
Weight 
______________________________________ 
Styrene resin (Trademark 88 
"D-125" made by Esso 
Sekiyu K.K.) 
Carbon black (Trademark 10 
"#44" made by Mitsubishi 
Chemical Industries, LTD.) 
First type quaternary-ammonium- 
2 
base containing copolymer 
(Mw. 10,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-1) is 99:1] 
##STR8## 
(I-1) 
##STR9## 
(II-1) 
______________________________________ 
The thus obtained toner particles are referred to as Toner No. 1 of the 
present invention. 
[Preparation of Carrier] 
______________________________________ 
Parts by Weight 
______________________________________ 
Core material: 
Spherical particles 
100 
of iron oxide with 
an average particle 
diameter of 100 .mu.m 
Coating liquid: 
5% toluene solution 
20 
of styrene - methyl- 
methacrylate copolymer 
______________________________________ 
A mixture of the above components with the above formulation was mixed in a 
fluidized bed coating apparatus, whereby the surface of the iron oxide 
particles was coated with the above coating liquid, and the coated liquid 
was dried and solidified, whereby a carrier for use in the present 
invention was obtained. 
Developer No. 1 was prepared by mixing the above prepared Toner No. 1 and 
carrier with the concentration of the toner in the developer being 3 wt.%. 
The charge quantity of this developer using this toner was 28 .mu.C/g. 
The developer was subjected to evaluation tests by use of a commercially 
available copying machine (Trademark "Ricopy FT 3300" made by Ricoh 
Company, Ltd.) by making 100,000 copies to evaluate the toner deposition 
on the background of developed images, the scattering of the toner from a 
development unit of the copying machine, and the occurrence of the spent 
phenomenon by the following respective evaluation methods: 
(1) Evaluation of Toner Deposition on the Background of Images 
A blank white original is copied, and the reflection density of the copy is 
measured by Macbeth densitometer. The evaluation value when there is no 
toner deposition on the copy paper is 0.12, and the larger the value, the 
greater the toner deposition on the copy paper and therefore the more the 
smearing of the copy paper with the toner. 
(2) Evaluation of Toner Scattering 
A white square paper sheet with a size of 4 cm.times.4 cm is applied to the 
inside of a front cover of the copying machine, and the toner deposited 
thereon by the scattering thereof is measured by the Macbeth densitometer. 
The evaluation value when there is no scattering of the toner and 
therefore no toner deposition on the paper is 0.12, and the larger the 
value, the greater the extent of the toner scattering. 
(3) Evaluation of Spent Phenomenon 
A sample developer is subjected to a blow-off treatment to remove the toner 
therefrom, and the weight of the developer is measured W.sub.1. To this 
developer, toluene is added, so that the toner deposited or adhering to 
the surface of the carrier particles is completely dissolved in the 
toluene and removed therefrom. The resulting developer is dried, and the 
weight of the developer is measured W.sub.2. 
The spent toner amount for evaluation of the spent phenomenon is determined 
in accordance with the following formula: 
EQU Spent toner amount W(%)=(W.sub.1 -W.sub.2)/W.sub.1 .times.100 
The results of the above evaluation tests are shown in Table 1. 
Comparative Example 1 
[Preparation of Comparative Toner No. 1] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 11 .mu.m were obtained: 
______________________________________ 
Parts by Weight 
______________________________________ 
Styrene resin (Trademark 
89.5 
"D-125" made by Esso 
Sekiyu K.K.) 
Carbon black (Trademark 
10 
"#44" made by Mitsubishi 
Chemical Industries, LTD.) 
First type quaternary-ammonium- 
0.5 
base containing copolymer 
(Mw. 10,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-1) is 95:5] 
______________________________________ 
The thus obtained toner particles are referred to as Comparative Toner No. 
1. 
Comparative Developer No. 1 was prepared by mixing the above prepared 
Comparative Toner No. 1 and the carrier prepared in Example 1 with the 
concentration of the toner in the developer being 3 wt.%. 
The charge quantity of this developer was using this toner 27 .mu.C/g, 
which was not so much different from the charge quantity of the developer 
prepared in Example 1. 
The above comparative developer was subjected to the same evaluation tests 
as in Example 1. The results are shown in Table 1. 
TABLE 1 
__________________________________________________________________________ 
Number of Copies Made 
Test Items 0 20000 
40000 
60000 
80000 
100000 
__________________________________________________________________________ 
Ex. 1 
Toner 0.12 
0.12 
0.12 
0.12 0.13 
0.13 
Deposition 
Toner 0.12 
0.12 
0.12 
0.13 0.13 
0.14 
Scattering 
Spent Amount 
0 0.01 
0.02 
0.02 0.03 
0.05 
Comp. 
Toner 0.13 
0.13 
0.14 
0.14 0.16 
0.19 
Ex. 1 
Deposition 
Toner 0.12 
0.14 
0.17 
0.20 0.13 
0.46 
Scattering 
Spent Amount 
0 0.02 
0.02 
0.03 0.04 
0.06 
__________________________________________________________________________ 
The results shown in the above Table 1 indicate that Developer No. 1 
comprising Toner No. 1 prepared in Example 1 is superior to Comparative 
Developer No. 1 prepared in Comparative Example 1. 
EXAMPLE 2 
The procedure of preparing Toner No. 1 in Example 1 was repeated except 
that the volume mean diameter of the toner particles prepared in Example 1 
was decreased to 8.5 .mu.m, whereby Toner No. 2 of the present invention 
was prepared. 
The procedure of preparing Developer No. 1 in Example 1 was repeated except 
that Toner No. 1 employed in Example 1 was replaced by the above prepared 
Toner No. 2, whereby Developer No. 2 was prepared. 
The thus prepared Developer No. 2 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 2. 
Comparative Example 2 
The procedure of preparing Comparative Toner No. 1 in Comparative Example 1 
was repeated except that the volume mean diameter of the toner particles 
prepared in Comparative Example 1 was decreased to 8.5 .mu.m, whereby 
Comparative Toner No. 2 was prepared. 
The procedure of preparing Comparative Developer No. 1 in Comparative 
Example 1 was repeated except that Comparative Toner No. 1 employed in 
Comparative Example 1 was replaced by the above prepared Comparative Toner 
No. 2, whereby Comparative Developer No. 2 was prepared. 
The thus prepared Comparative Developer No. 2 was subjected to the same 
evaluation tests as in Example 1. The results are shown in Table 2. 
TABLE 2 
__________________________________________________________________________ 
Number of Copies Made 
Test Items 0 20000 
40000 
60000 
80000 
100000 
__________________________________________________________________________ 
Ex. 2 
Toner 0.12 
0.12 
0.12 
0.12 0.13 
0.13 
Deposition 
Toner 0.12 
0.12 
0.12 
0.13 0.14 
0.15 
Scattering 
Spent Amount 
0 0.01 
0.02 
0.03 0.04 
0.06 
Comp. 
Toner 0.13 
0.13 
0.14 
0.16 0.19 
0.21 
Ex. 2 
Deposition 
Toner 0.12 
0.16 
0.20 
0.36 0.44 
0.69 
Scattering 
Spent Amount 
0 0.03 
0.05 
0.09 0.12 
0.21 
__________________________________________________________________________ 
The results shown in the above Table 2 indicate that Developer No. 2 
comprising Toner No. 2 prepared in Example 2 is superior to Comparative 
Developer No. 2 prepared in Comparative Example 2. 
EXAMPLE 3 
[Preparation of Toner No. 3] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 6.5 .mu.m were obtained: 
______________________________________ 
Parts by 
Weight 
______________________________________ 
Styrene resin (Trademark 86 
"D-125" made by Esso 
Sekiyu K.K.) 
Carbon black (Trademark 10 
"#44" made by Mitsubishi 
Chemical Industries, LTD.) 
First type quaternary-ammonium- 
4 
base containing copolymer 
(Mw. 20,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-2) is 98.5:1.5] 
##STR10## 
(I-1) 
##STR11## 
(II-2) 
______________________________________ 
The thus obtained toner particles are referred to as Toner No. 3 of the 
present invention. 
[Preparation of Carrier] 
______________________________________ 
Parts by Weight 
______________________________________ 
Core material: 
Spherical particles 
100 
of ferrite with an 
average particle 
diameter of 100 .mu.m 
Coating liquid: 
Silicone resin solution 
20 
(Trademark "SR2411" made 
by Dow Corning Toray 
Silicone Co., Ltd.) 
______________________________________ 
A mixture of the above components with the above formulation was mixed in a 
fluidized bed coating apparatus, whereby the surface of the ferrite 
particles was coated with the above coating liquid, and the coated liquid 
was dried and solidified, whereby a carrier for use in the present 
invention was obtained. 
Developer No. 3 was prepared by mixing the above prepared Toner No. 3 and 
carrier with the concentration of the toner in the developer being 3 wt. 
%. 
The charge quantity of this developer using the toner was 22 .mu.C/g. 
The above prepared Developer No. 3 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 3. 
Comparative Example 3 
[Preparation of Comparative Toner No. 3] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 6.5 .mu.m were obtained: 
______________________________________ 
Parts by weight 
______________________________________ 
Styrene resin (Trademark 
89.5 
"D-125" made by Esso 
Sekiyu K.K.) 
Carbon black (Trademark 
10 
"#44" made by Mitsubishi 
Chemical Industries, LTD.) 
First type quaternary-ammonium- 
0.5 
base containing copolymer 
(Mw. 20,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-2) is 90:10] 
______________________________________ 
The thus obtained toner particles are referred to as Comparative Toner No. 
3. 
Comparative Developer No. 3 was prepared by mixing the above prepared 
Comparative Toner No. 3 and the carrier prepared in Example 3 with the 
concentration of the toner in the developer being 3 wt. %. 
The charge quantity of this comparative developer was 24 .mu.C/g, which was 
not so much different from the charge quantity of Developer No. 3 prepared 
in Example 3. 
The above Comparative Developer No. 3 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 3. 
TABLE 3 
__________________________________________________________________________ 
Number of Copies Made 
Test Items 0 20000 
40000 
60000 
80000 
100000 
__________________________________________________________________________ 
Ex. 1 
Toner 0.12 
0.12 
0.12 
0.12 0.12 
0.12 
Deposition 
Toner 0.12 
0.12 
0.12 
0.13 0.12 
0.12 
Scattering 
Spent Amount 
0 0 0.01 
0.01 0.02 
0.02 
Comp. 
Toner 0.12 
0.13 
0.14 
0.15 0.16 
0.18 
Ex. 1 
Deposition 
Toner 0.12 
0.15 
0.27 
0.32 0.40 
0.55 
Scattering 
Spent Amount 
0 0.02 
0.04 
0.07 0.10 
0.11 
__________________________________________________________________________ 
The results shown in the above Table 3 indicate that Developer No. 3 
comprising Toner No. 3 prepared in Example 2 is superior to Comparative 
Developer No. 3 prepared in Comparative Example 3. 
EXAMPLE 4 
[Preparation of Toner No. 4] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 11 .mu.m were obtained: 
______________________________________ 
Parts by 
Weight 
______________________________________ 
Styrene resin (Trademark 88 
"D-125" made by Esso 
Sekiyu K.K.) 
Carbon black (Trademark 10 
"#44" made by Mitsubishi 
Chemical Industries, LTD.) 
Second type quaternary-ammonium- 
2 
base containing copolymer 
(Mw. 10,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-1):the repeat 
unit of formula (III-1) is 
90:1:9] 
##STR12## 
(I-1) 
##STR13## 
(II-1) 
##STR14## 
(III-1) 
______________________________________ 
The thus obtained toner particles are referred to as Toner No. 4 of the 
present invention. 
[Preparation of Carrier] 
______________________________________ 
Parts by Weight 
______________________________________ 
Core material: 
Spherical particles 
100 
of iron oxide with 
an average particle 
diameter of 100 .mu.m 
Coating liquid: 
5% toluene solution 
20 
of styrene - methyl- 
methacrylate copolymer 
______________________________________ 
A mixture of the above components with the above formulation was mixed in a 
fluidized bed coating apparatus, whereby the surface of the iron oxide 
particles was coated with the above coating liquid, and the coated liquid 
was dried and solidified, whereby a carrier for use in the present 
invention was obtained. 
Developer No. 4 was prepared by mixing the above prepared Toner No. 4 and 
carrier with the concentration of the toner in the developer being 3 wt. 
%. 
The charge quantity of this developer was 25 .mu.C/g. 
The above prepared Developer No. 4 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 4. 
Comparative Example 4 
[Preparation of Comparative Toner No. 4] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 11 .mu.m were obtained: 
______________________________________ 
Parts by weight 
______________________________________ 
Styrene resin (Trademark 
89.5 
"D-125", made by Esso 
Sekiyu K.K.) 
Carbon black (Trademark 
10 
"#44" made by Mitsubishi 
Chemical Industries, LTD.) 
Second type quaternary-ammonium- 
0.5 
base containing copolymer 
(Mw. 10,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-1):the repeat 
unit of formula (III-1) is 
55:5:40] 
______________________________________ 
The thus obtained toner particles are referred to as Comparative Toner No. 
4. 
Comparative Developer No. 4 was prepared by mixing the above prepared 
Comparative Toner No. 4 and the carrier prepared in Example 4 with the 
concentration of the toner in the developer being 3 wt. %. 
The charge quantity of this developer was 24 .mu.C/g, which was not so much 
different from the charge quantity of Developer No. 4 prepared in Example 
4. 
The above Comparative Developer No. 4 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 4. 
TABLE 4 
__________________________________________________________________________ 
Number of Copies Made 
Test Items 0 20000 
40000 
60000 
80000 
100000 
__________________________________________________________________________ 
Ex. 4 
Toner 0.12 
0.12 
0.12 
0.12 0.13 
0.13 
Deposition 
Toner 0.12 
0.12 
0.12 
0.1222 
0.13 
0.13 
Scattering 
Spent Amount 
0 0.01 
0.01 
0.02 0.03 
0.04 
Comp. 
Toner 0.13 
0.13 
0.13 
0.14 0.15 
0.18 
Ex. 4 
Deposition 
Toner 0.12 
0.14 
0.15 
0.19 0.28 
0.44 
Scattering 
Spent Amount 
0 0.02 
0.02 
0.03 0.04 
0.05 
__________________________________________________________________________ 
The results shown in the above Table 4 indicate that Developer No. 4 
comprising Toner No. 4 prepared in Example 4 is superior to Comparative 
Developer No. 4 prepared in Comparative Example 4. 
EXAMPLE 5 
[Preparation of Toner No. 5] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 12 .mu.m were obtained: 
______________________________________ 
Parts by Weight 
______________________________________ 
Styrene resin prepared 
88 
by copolymerizing 
styrene and the 
repeat unit of formula 
(III-1) in Example 4 which 
is in an amount of 20 wt. % 
Carbon black (Trademark 
10 
"#44", made by Mitsubishi 
Chemical Industries, LTD.) 
Second type quaternary-ammonium- 
2 
base containing copolymer 
(Mw. 10,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-1):the repeat 
unit of formula (III-1) is 
90:1:9] which is the same 
quaternary-ammonium-base 
containing copolymer as that 
used in Example 4 
______________________________________ 
The thus obtained toner particles are referred to as Toner No. 5 of the 
present invention. 
Developer No. 5 was prepared by mixing the above prepared Toner No. 5 and 
the same carrier as prepared in Example 4 with the concentration of the 
toner in the developer being 3 wt. %. 
The charge quantity of this developer was 29 .mu.C/g. 
The above prepared Developer No. 5 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 5. 
EXAMPLE 6 
The procedure for preparing Toner No. 5 in Example 5 was repeated except 
that the binder resin employed in Example 5 was replaced by a styrene 
resin which was the same styrene resin as that employed in Example 5 
except that the repeat unit of formula (III-1) was eliminated therefrom, 
that is, styrene homopolymer, whereby Toner No. 6 was prepared. 
The procedure for preparing Developer No. 5 in Example 5 was also repeated 
except that Toner No. 5 employed in Example 5 was replaced by the above 
prepared Toner No. 6, whereby Developer No. 6 was prepared. 
The charge quantity of this developer was 27 .mu.C/g, which was not so much 
different from the charge quantity of Developer No. 5 prepared in Example 
5. 
The above prepared Developer No. 6 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 6. 
TABLE 5 
__________________________________________________________________________ 
Number of Copies Made 
Test Items 0 20000 
40000 
60000 
80000 
100000 
__________________________________________________________________________ 
Ex. 1 
Toner 0.12 
0.12 
0.12 
0.12 0.12 
0.13 
Deposition 
Toner 0.12 
0.12 
0.12 
0.12 0.12 
0.13 
Scattering 
Spent Amount 
0 0 0.01 
0.01 0.01 
0.02 
Ex. 6 
Toner 0.12 
0.12 
0.12 
0.13 0.13 
0.17 
Deposition 
Toner 0.12 
0.12 
0.12 
0.12 0.13 
0.13 
Scattering 
Spent Amount 
0 0.01 
0.01 
0.02 0.02 
0.03 
__________________________________________________________________________ 
The results shown in the above Table 5 indicate that Developer No. 5 
comprising Toner No. 5 prepared in Example 5 is superior in the anti-spent 
performance to Developer No. 6 prepared in Example 6. 
EXAMPLE 7 
The procedure of preparing Toner No. 5 in Example 5 was repeated except 
that the volume mean diameter of the toner particles prepared in Example 1 
was decreased to 8.5 .mu.m, whereby Toner No. 7 of the present invention 
was prepared. 
The procedure of preparing Developer No. 5 in Example 5 was repeated except 
that Toner No. 5 employed in Example 5 was replaced by the above prepared 
Toner No. 7, whereby Developer No. 7 was prepared. 
The thus prepared Developer No. 7 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 6. 
EXAMPLE 8 
The procedure of preparing Toner No. 6 in Example 6 was repeated except 
that the volume mean diameter of the toner particles prepared in Example 6 
was decreased to 8.5 .mu.m, whereby Toner No. 8 was prepared. 
The procedure of preparing Developer No. 6 in Example 6 was repeated except 
that Toner No. 6 employed in Example 6 was replaced by the above prepared 
Toner No. 8, whereby Developer No. 8 was prepared. 
The thus prepared Developer No. 8 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 6. 
TABLE 6 
__________________________________________________________________________ 
Number of Copies Made 
Test Items 0 20000 
40000 
60000 
80000 
100000 
__________________________________________________________________________ 
Ex. 7 
Toner 0.12 
0.12 
0.12 
0.12 0.13 
0.13 
Deposition 
Toner 0.12 
0.12 
0.12 
0.13 0.13 
0.15 
Scattering 
Spent Amount 
0 0 0.01 
0.02 0.03 
0.05 
Ex. 8 
Toner 0.12 
0.12 
0.13 
0.13 0.13 
0.14 
Deposition 
Toner 0.12 
0.12 
0.13 
0.14 0.15 
0.16 
Scattering 
Spent Amount 
0 0.01 
0.01 
0.02 0.03 
0.05 
__________________________________________________________________________ 
The results shown in the above Table 6 indicate that Developer No. 7 
comprising Toner No. 7 prepared in Example 7 is superior in the anti-spent 
performance to Developer No. 8 prepared in Example 8. 
EXAMPLE 9 
[Preparation of Toner No. 9] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 6.5 .mu.m were obtained: 
______________________________________ 
Parts by 
Weight 
______________________________________ 
Polyester resin prepared 86 
by copolymerization so 
as to include the repeat 
unit of formula (III-1) 
in Example 4 in an amount 
of 20 wt. % 
Carbon black (Trademark 10 
"#44" made by Mitsubishi 
Chemical Industries, LTD.) 
Second type quaternary-ammonium- 
4 
base containing copolymer 
(Mw. 25,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-1):the repeat 
unit of formula (III-1) is 
90.0:1.5:8.5] 
##STR15## 
(I-1) 
##STR16## 
(II-1) 
##STR17## 
(III-1) 
______________________________________ 
The thus obtained toner particles are referred to as Toner No. 9 of the 
present invention. 
[preparation of Carrier] 
______________________________________ 
Parts by Weight 
______________________________________ 
Core material: 
Spherical particles 
100 
of ferrite with 
an average particle 
diameter of 100 .mu.m 
Coating liquid: 
Silicone resin solution 
20 
(Trademark "SR2411" made 
Dow Corning Toray 
Silicone Co., Ltd. 
______________________________________ 
A mixture of the above components with the above formulation was mixed in a 
fluidized bed coating apparatus, whereby the surface of the ferrite 
particles was coated with the above coating liquid, and the coated liquid 
was dried and solidified, whereby a carrier for use in the present 
invention was obtained. 
Developer No. 9 was prepared by mixing the above prepared Toner No. 9 and 
carrier with the concentration of the toner in the developer being 3 wt. 
%. 
The charge quantity of this developer using the toner was 25 .mu.C/g. 
The above prepared Developer No. 9 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 7. 
Comparative Example 5 
[Preparation of Comparative Toner No. 6] 
The following components were kneaded and pulverized in an extruder, and 
the pulverized mixture was classified, whereby toner particles with a 
volume mean diameter of 6.5 .mu.m were obtained: 
______________________________________ 
Parts by Weight 
______________________________________ 
Polyester resin 99.5 
Carbon black (Trademark 
10 
"#44" made by Mitsubishi 
Chemical Industries, LTD.) 
Second type quaternary-ammonium- 
0.5 
base containing copolymer 
(Mw. 25,000) [the ratio of 
the repeat unit of formula 
(I-1):the repeat unit of 
formula (II-1):the repeat 
unit of formula (III-1) is 
89:10:1 
______________________________________ 
The thus obtained toner particles are referred to as Comparative Toner No. 
5. 
Comparative Developer No. 5 was prepared by mixing the above prepared 
Comparative Toner No. 5 and the carrier with the concentration of the 
toner in the developer being 3 wt. %. 
The charge quantity of this developer using the above toner was 27 .mu.C/g, 
which was not so much different from the charge quantity of the developer 
prepared in Example 9. 
The above Comparative Developer No. 5 was subjected to the same evaluation 
tests as in Example 1. The results are shown in Table 7. 
TABLE 7 
__________________________________________________________________________ 
Number of Copies Made 
Test Items 0 20000 
40000 
60000 
80000 
100000 
__________________________________________________________________________ 
Ex. 9 
Toner 0.12 
0.12 
0.12 
0.12 0.12 
0.12 
Deposition 
Toner 0.12 
0.12 
0.12 
0.12 0.12 
0.12 
Scattering 
Spent Amount 
0 0 0 0.01 0.01 
0.02 
Comp. 
Toner 0.12 
0.12 
0.13 
0.14 0.15 
0.18 
Ex. 5 
Deposition 
Toner 0.12 
0.14 
0.24 
0.30 0.38 
0.55 
Scattering 
Spent Amount 
0 0.01 
0.03 
0.06 0.09 
0.11 
__________________________________________________________________________ 
The results shown in the above Table 7 indicate that Developer No. 9 
comprising Toner No. 9 prepared in Example 9 is superior to Comparative 
Developer No. 5 prepared in Comparative Example 5.