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The present invention relates to an electrostatic image
developing toner useful for developing an electrostatic
latent image in the field of electrophotographic or
electrostatic recording materials, More particularly, it
relates to an electrostatic image-developing toner to be
used in an image forming apparatus whereby a non-transferred
toner after the transfer is recovered by a
cleaning process and re-used by recycling. Further, it
relates to an electrostatic image developing toner having
an excellent electrification rising property and
electrification stability.
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In an image forming process by an electrophotographic
system, an electrostatic latent image is formed on a
photoreceptor made of an inorganic or organic material, and
the latent image is developed by a toner, then transferred
to a paper sheet, a plastic film or the like and fixed to
obtain a visible image. The photoreceptor is positively
electrifiable or negative electrifiable depending
upon its construction. When a printed portion is to be
retained as an electrostatic latent image by exposure,
development is carried out by means of an inversely
electrifiable toner. On the other hand, when reversal
development is to be carried out by removing
electrification of a printed portion, development is
carried out by means of a toner electrifiable with the same
code of electricity.
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In the above process, the toner on the photoreceptor
will not be all transferred, and a non-transferred toner
will remain at a level of from 5 to 20 wt%. Such a non-transferred
toner is usually recovered by e.g. a step of
scraping by a cleaning blade and collected as a waste toner.
However, with such a waste toner, various properties such
as electrification properties or resin properties are
substantially changed as compared with a fresh toner, and
it used to be usually impossible to reuse such a waste
toner.
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In recent years, along with an increase in demand for
printers and copying machines, consumption of toners has
remarkably increased, and at the same time, the amount of
waste materials discharged from electrophotographic
processes has likely increased. In view of adverse effects
to the environment of such waste materials, it has been
proposed to reuse waste toners. For example, JP-A-1-214874
proposes a toner using, as a binder resin, a specific
polyester resin containing an aliphatic diol, or JP-A-2-110572
proposes a toner wherein a metal-crosslinked
styrene/acrylic copolymer is used as a binder resin, and a
large amount of a polyolefin is added thereto. However, in
either case, the elements constituting the toner are
restricted, and there is an additional problem such that
the storage stability tends to deteriorate. Further, JP-A-7-301954
proposes to reuse a waste toner with respect to a
toner containing, as a charge control agent, an azo type
iron complex compound. However, also in the case of a toner
employing such a charge control agent, it is impossible to
obtain a recovered toner having a performance equal to the
fresh toner, since a decrease in the amount of the charge
control agent in the recovered waste toner or broadening of
the electrification distribution will occur, and problems
have not completely been solved. Further, such a charge
control agent has a color and thus has had a problem that
it can not be used for a color toner which is also
increasingly demanded in recent years.
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Further, for example, in the case of a two component
development, in order to impart an adequate tribocharge to
the developer, it is necessary to drive the developing
section for a predetermined period of time during operation
of the system, to obtain a tribocharge required for the
development process. Usually, it takes a few minutes as a
time for this preparation till the first copy. In recent
years, from the viewpoint of energy saving, it is common to
adopt a system in which a printer or a copying machine
which is not used for a certain period of time, is
maintained in a system standby state, and at the time of
initiating printing, the developing section is driven again
to obtain a tribocharge. Accordingly, it is desired that
the time till the developer obtains the necessary
tribocharge is as short as possible, but in reality, it is
not necessarily possible to obtain an adequate initial
tribocharge.
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Further, in recent years, it is common to employ a mono
component development for e.g. small-size printers. In such
a case, it is required to complete the electrification step
of the toner in a very short time. For this purpose, it has
been proposed to apply a DC voltage during development to
inject an electrical charge or to improve the fluidity by
adding e.g. silica to improve the rising of the initial
electrification. However, by the method of injecting the
electrical charge, it is necessary to carry out very
delicate adjustment of the bias for development, and there
has been a problem that the apparatus tends to be expensive,
or the electrification can not be maintained and will
decrease, whereby it has been often observed that the toner
remaining after the transfer increases or an image defect
such as fogging results. On the other hand, by the use of a
superplasticizing agent, the apparent rising of
electrification will be improved, but this is attributable
to the fact that the agent which is fine particles, is
strongly charged, and the electrification of the toner
itself remains to be low. Accordingly, problems may happen
such that the highly electrified agent selectively remains
on the developing parts or on the photoreceptor. Thus, this
method has not been a method effective to improve the
rising of electrification.
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As a toner to be used for such developing methods, it
has been common to employ a fine powder having a colorant
dispersed in a resin. For example, in the case of a non-magnetic
toner, a colorant such as carbon black is
dispersed in a binder resin such as a styrene/acrylic
copolymer resin, followed by pulverization and
classification to obtain fine particles of from about 1 to
30 µm, which are used as a toner. Further, as a magnetic
toner, it is common to employ one having e.g. magnetite
incorporated as a colorant.
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A dry development method to be used for such
electrophotography may generally be classified into a two
component development and a mono component development. The
system employing a mono component development has a merit
that the developing apparatus may be made small-sized, but
as compared with the two component development, the
electrostatic image developing toner is required to gain a
predetermined quantity of electrification in a short period
of time, whereby it used to have problems that a limited
material must be used, and the design allowance of the
developing system is very narrow. On the other hand, the
two component development is excellent in the
electrification control, but has had a problem that the
apparatus tends to be complex and large-sized.
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In order for such an electrostatic developing toner to
gain a desired level of tribocharge, it has heretofore been
known to incorporate a certain charge control agent to the
toner. However, such a charge control agent usually has a
nature to soil a toner carrier such as a developing roller,
whereby the tribocharge tends to remarkably decrease by
repeated printing operation over a long period of time,
thus leading to problems of image defects such as a
decrease in the image density, background fogging and
scattering in the machine. In order to maintain a constant
clear image in repeated printing operation for a long
period of time, it is not sufficient to merely stabilize
the tribocharge, and it is necessary to take the magnetic
properties of the toner into consideration. The magnetic
properties of magnetic toners are reported, for example, in
JP-A-58-95748, JP-A-58-98744 and JP-A-6-332240.
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JP-A-58-95748 discloses that saturation magnetization
is influential over transportability of the magnetic toner
particles. Namely, when the saturation magnetization is
lower than a certain level, the magnetization transporting
force decreases, thereby leading to uneven development. On
the other hand, if the saturation magnetization is higher
than a certain level, the amount of the magnetic powder
necessarily increases, whereby the fixing property or the
developing property tends to deteriorate. Whereas, if the
coercive force is lower than a certain level, development
failure tends to result, and if it is higher than a certain
level, coagulation of toner particles increases, thus
leading to a decrease in transportability.
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JP-A-6-332240 discloses that stability of an image for
a long period of time can be obtained when there is no
change in the particle size of the toner, and that in such
a case, it is important to maintain the balance of the
tribocharge and the magnetic properties by using a certain
specific charge control agent.
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As a means to solve such problems, certain chromium
compounds have been proposed in JP-B-43-17955, JP-B-55-42752
and JP-B-63-1994. By using such charge control agents,
it is certainly possible to maintain the constant effect
for controlling electrification and to produce a clear
image even in repeated printing operation for a long period
of time. However, there has been a problem from the
viewpoint of environmental safety, since the compounds are
chromium compounds.
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JP-A-6-332240 proposes a negatively electrifiable
charge control agent of an iron compound taking safety into
consideration against the above chromium compounds. However,
with such an iron compound, the initial rising of
electrification and saturated tribocharge are not
comparable to the effects obtainable by the above chromium
compounds, and it has been difficult to obtain an adequate
performance in a mono component development. Under these
circumstances, it has been desired to develop a charge
control agent which is safe and excellent in the
electrification controlling performance for a long period
of time.
-
It is an object of the present invention to provide an
electrostatic image developing toner having the above-described
problems solved, i.e. an electrostatic image
developing toner suitable for reuse by recycling.
-
Namely, it is an object of the present invention to
provide an electrostatic image developing toner which is
capable of obtaining a clear image having an adequate image
density free from background fogging or scattering of the
toner in the machine, in any environment in an
electrophotographic system capable of recycling. Further,
it is intended to obtain a similar clear image also in a
recycling system of a color toner, for which the demand has
been rapidly increasing in recent years.
-
Further, another object of the present invention is to
provide an electrostatic image developing toner which is
excellent in the rising of electrification and has
electrification stability for a long period of time.
-
Namely, the present invention is to provide an
electrostatic image developing toner which is capable of
obtaining a clear image having a sufficient imager density
from the first print, without background fogging or
scattering of the toner in the machine and which is capable
of maintaining the clear image for a long period of time,
in an electrophotographic system.
-
Further, another object of the present invention is to
provide an electrostatic image developing toner which is
capable of forming a clear image by maintaining a constant
electrification controlling effect even in repeated
printing operation for a long period of time and is free
from a problem from the viewpoint of environmental safety
and which has an excellent electrification rising property
and electrification stability.
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To present an electrostatic image developing toner
suitable tor recycling, the present invention provides an
electrostatic image developing toner to be used for an
image forming method wherein in an electrophotographic
process of forming an electrostatic latent image on a
photoreceptor made of an inorganic or organic material,
developing it with a toner, transferring it to a paper
sheet, a plastic film or the like, and fixing it to form a
visible image, the toner remaining on the photoreceptor
after the transfer, is recovered, and the recovered toner
is reused in the development process, said electrostatic
image developing toner comprising at least a binder resin,
a colorant and a charge control agent, wherein the charge
control agent is represented by the following formula (1):
wherein R
1 is quaternary carbon, methine or methylene and
may contain a hetero atom of N, S, O or P, each of R
2 and R
3
which are independent of each other, is an alkyl group, an
alkenyl group, an alkoxy group, an aryl, aryloxy, aralkyl
or aralkyloxy group which may have a substituent, a halogen
atom, a hydrogen atom, a hydroxyl group, an amino group
which may have a substituent, a carboxyl group, a carbonyl
group, a nitro group, a nitroso group, a sulfonyl group or
a cyano group, R
4 is a hydrogen atom or an alkyl group, 1 is
an integer of from 0 to 12, m is an integer of from 1 to 20,
n is an integer of from 0 to 20, o is an integer of from 0
to 4, p is an integer of from 0 to 4, r is an integer of
from 1 to 20, and s is an integer of from 0 to 20.
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Along with a remarkable increase in demand of an
electrostatic image developing toner for printers and
copying machines in recent years, the amount of a waste
toner to be recovered has been substantially increasing.
Such a waste toner is usually recovered from a cleaning
process, stored in a waste toner box and then discharged
from the system. Such a waste toner can not be reused,
because if it is supplied again to the developing section
and used for development, there will be problems such as a
decrease in the image density, an increase of fogging and
soiling in the machine due to scattering of the toner.
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To investigate the causes for such problems, the
present inventors have measured various physical properties
of a fresh toner and a waste toner. As a result, it has
been ascertained that with a toner having such problems,
the amount of the charge control agent contained in the
toner, which should be at the same level as in a fresh
toner, is substantially decreased in the waste toner.
Further, with respect to both toners, the electrification
distributions were measured, and it has been found that as
compared with the fresh toner, with the waste toner, the
proportion of an inversely electrified toner is increased,
and the electrification distribution is broadened.
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Namely, the cause for the above-mentioned image
deterioration and soiling in the machine, is considered to
be such that in the transfer process, among developing
toner particles on the photoreceptor, only sufficiently
electrified toner particles will be selectively transferred,
and weakly or inversely electrified toner particles will
remain as a non-transferred toner on the photoreceptor and
will be recovered in a cleaning process, whereby the
electrification distribution of the recovered toner tends
to be broadened, and the proportion of inversely
electrified toner particles tends to increase.
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The reason for such selective transfer is considered to
be such that in a fresh toner, toner particles having a
small proportion of a charge control agent are already
present, and such toner particles having a small proportion
of a charge control agent will selectively remain during
the transfer and will be recovered, since with such toner
particles, no adequate tribocharge will be obtained. This
is evident also from the fact that the content of the
charge control agent in a recovered toner is rather low.
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To solve such problems, the present inventors have
conducted an extensive study and as a result, have found it
very effective to employ the compound of the above formula
(1) as a charge control agent in a toner to be used for a
recycling system for a waste toner.
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The compound is also thermally stable and is not
susceptible to a thermal change during the
electrophotographic process, whereby a stabilized
electrification property can be maintained. Further, it can
be uniformly dispersed in any binder resin, and thus
presents a feature that the electrification distribution of
a fresh toner is very uniform. Further, the content of the
compound in the non-transferred recovered toner was
analyzed and found to be the same content as in the fresh
toner, and the saturated tribochange and electrification
distribution were also found to be the same.
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To present an electrostatic image-developing toner
which is excellent in the electrification rising and which
has an electrification stability for a long period of time,
the present invention provides an electrostatic image
developing toner to be used for an image forming method
which comprises forming an electrostatic latent image on a
photoreceptor made of an inorganic or organic material,
developing it with a toner, transferring it to a paper
sheet, a plastic film or the like, and fixing it to form a
visible image, said toner comprising at least a binder
resin, a colorant and a charge control agent, wherein the
charge control agent comprises at least one zirconium
compound of the above-mentioned formula (1) and at least
one specific azo metal complex.
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In an electrophotographic process, in order to impart a
sufficient tribocharge to an electrostatic image developing
toner, in a two component development, it is necessary to
drive the developing section for a certain period of time
at the time of operation of the system to obtain a
tribocharge necessary for the developing step. The shorter
the period of time until this necessary tribocharge is
obtained, the better. In reality, however, it usually takes
a few minutes as the time until a first copy, and a
satisfactory initial electrification has not necessarily
been obtained. Further, also in a mono component
development, the system tends to be expensive, and an
excessive charge control agent is used in order to secure a
sufficient electrification rising property, whereby there
is a serious problem such that the charge control agent
tends to remain on various parts.
-
The present inventors have conducted an extensive study
to solve such problems and as a result, have found it very
effective that the charge control agent comprises a
zirconium compound of the above-mentioned formula (1) and a
specific azo metal complex.
-
The above compound (1) is thermally stable and is not
susceptible to a thermal change during the
electrophotographic process, whereby a constant
electrification property can be maintained. Further, with
respect to the electrification property, it shows an
extremely quick electrification rising property, and its
tribocharge has been found to be higher than an azo metal
complex which is presently mostly commonly employed.
However, when the above compound (1) is used alone, it has
been found that the tribocharge tends to increase gradually
during tribe-electrification for a long period of time,
whereby it has been found that a problem such as a decrease
in the image density is likely to result especially when a
long term electrification stability is of importance for
e.g. a high speed copying machine.
-
On the other hand, when an azo metal complex which is
presently most commonly used, is used alone, it has been
impossible to obtain a sufficient rising of electrification,
although there is no problem in the long term
electrification stability.
-
In the present invention, by incorporating the above
compound (1) excellent in the electrification rising
property and a specific azo metal complex excellent in the
long term electrification stability, especially when the
zirconium compound is incorporated in an amount of at least
5 wt% of the azo metal complex, it has been made possible
to obtain an electrostatic image developing toner having
the characteristics of both components.
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The specific azo metal complex may, for example, be an
azo type chromium complex, an azo type zinc complex or an
azo type iron complex. Specifically, azo metal complexes of
the following chemical formula may be mentioned, but the
specific azo metal complex is not limited to such specific
examples.
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The electrophotographic toner of the present invention
i.e. the electrostatic image developing toner suitable for
recycling, is composed basically of a binder resin, a
colorant (a pigment, a dye or a magnetic material) and a
charge control agent comprising a zirconium compound of the
above formula (1). As a method for preparing the
electrophotographic toner, there may be mentioned, for
example, a method wherein such a mixture is kneaded while
melting the binder resin by a heat-mixing apparatus and
cooled, followed by rough pulverization, fine pulverization
and classification, a method wherein such a mixture is
dissolved in a solvent, followed by spraying to form fine
particles, which are then dried and classified, or a method
wherein a colorant and the compound of the formula (1) are
dispersed in suspended monomers particles, followed by
polymerization.
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The electrophotographic toner of the present invention
i.e. the electrostatic image developing toner which is
excellent in the electrification rising property and which
has a long term electrification stability, is composed
basically of a binder resin, a colorant (a pigment, a dye
or a magnetic material), and a charge control agent
comprising the zirconium compound of the formula (1) and an
azo metal complex. As a method for preparing such an
electrophotographic toner, there may be mentioned, for
example, a method wherein such a mixture is kneaded while
melting the binder resin by a heat-mixing apparatus and
cooled, followed by rough pulverization, fine pulverization
and classification, a method wherein such a mixture is
dissolved in a solvent, followed by spraying to form fine
particles, which are then dried and classified, or a method
wherein a colorant and the charge control agent comprising
the compound of the formula (1) and an azo metal complex,
are dispersed in suspended monomer particles, followed by
polymerization.
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To present an electrostatic image developing toner
having an excellent electrification rising property and
electrification stability, which is capable of maintaining
a constant electrification control effect and providing a
clear image even in repeated printing operation for a long
period of time and which is free from a problem from the
viewpoint of environmental safety, the present invention
provides an electrostatic image developing toner to be used
for an image forming method which comprises forming an
electrostatic latent image on a photoreceptor made of an
inorganic or organic material, developing it with a toner,
transferring it to a paper sheet, a plastic film or the
like, and fixing it to form a visible image, said toner
comprising at least a binder resin, a magnetic material and
a charge control agent of the above formula (1) and having
a saturation magnetization of from 2 to 50 Am2/kg and a
coercive force of from 40 to 200 oersted.
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In a one component developer process as an
electrophotographic process, it is necessary to use a
charge control agent in order to impart a sufficient
tribocharge in a very short period of time to an
electrostatic image developing toner. It is known that a
certain chromium compound is effective for remarkably
improving the electrification rising property. However, it
has had a problem from the viewpoint of environmental
safety, as it is a chromium compound. It is also known that
a certain iron compound exhibits a negative electrification
control effect, but as compared with a chromium compound,
this compound is inadequate in the electrification rising
property in a mono component development.
-
The present inventors have conducted an extensive study
to solve such problems and as a result, have found it very
effective that the charge control agent is a zirconium
compound of the above formula (1).
-
The compound (1) is thermally stable and is not
susceptible to a thermal change during the
electrophotographic process, whereby a constant
electrification property can be maintained. Further, with
respect to the electrification property, it exhibits a very
quick electrification rising property, and its tribocharge
has been found to be higher than the above-mentioned azo
chromium complex or the azo iron complex which are
presently most commonly employed.
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The present inventors have made a magnetic toner for a
mono component development by using the above compound (1)
excellent in the electrification rising property. Further,
in order to obtain a clear initial image by using this
toner, a study has been made by applying various magnetic
properties of the magnetic toner, and as a result, it has
been found that when the magnetic properties are within a
certain range, the image quality of an initial image will
be excellent. Namely, it has been found that when the above
compound (1) is applied to an electrostatic image
developing magnetic toner having a saturation magnetization
of from 20 to 50 Am2/kg and a coercive force of from 40 to
200 oersted, the balance of the tribocharge and the
magnetic properties will be proper, a sufficient image
density can be obtained, and a good image quality can be
maintained without background fogging, and the present
invention has been accomplished on the basis of this
discovery.
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Such an electrophotographic toner of the present
invention is composed basically of a binder resin, a
magnetic material as a colorant and a charge control agent
comprising the zirconium compound of the above formula (1).
As a method for producing such an electrophotographic toner,
there may be mentioned, for example, a method wherein such
a mixture is kneaded while melting the binder resin by a
heat-mixing apparatus and cooled, followed by rough
pulverization, fine pulverization and classification, a
method wherein such a mixture is dissolved in a solvent,
followed by spraying to obtain fine particles, which are
then dried and classified, or a method wherein a colorant
and a compound of the formula (1) are dispersed in
suspended monomer particles, followed by polymerization.
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The binder resin to be used in the present invention
preferably has a glass transition point of from 40 to 90°C,
a number average molecular weight (Mn) of from 1,500 to
50,000, a weight average molecular weight (Mw) of from
10,000 to 3,000,000, an acid value of at most 50 and an
acid value of at least 50.
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The binder resin is, for example, a polymer or a
copolymer of a monomer selected from the group consisting
of styrene type monomers, acrylic monomers and methacrylic
monomers, and specifically it may be made of a monomer
component selected from the group consisting of styrene, o-methylstyrene,
m-methylstyrene, p-methylstyrene, p-methoxystyrene,
p-ethylstyrene, acrylic acid, α-ethylacrylic
acid, crotonic acid, methyl acrylate, ethyl
acrylate, n-butyl acrylate, isobutyl acrylate, n-propyl
acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl
acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl
acrylate, 2-hydroxyethyl acrylate, methacrylic acid, methyl
methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl
methacrylate, isobutyl methacrylate, n-octyl
methacrylate, dodecyl methacrylate, 2-ethylhexyl
methacrylate, stearyl methacrylate, phenyl methacrylate,
dimethylaminoethyl methacrylate, diethylaminoethyl
methacrylate, 2-hydroxyethyl methacrylate, acrylonitrile,
methacrylonitrile and acrylamide.
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In the case of a polyester type, the alcohol component
may, for example, be a diol such as ethylene glycol,
propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol,
diethylene glycol, triethylene glycol, 1,5-pentanediol,
1,6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol
or a bisphenol A derivative such as hydrogenated
bisphenol A, or a known polyhydric alcohol such as glycerol,
sorbitol, sorbitan or pentaerythritol. The acid component
may, for example, be a benzenedicarboxylic acid or its
anhydride, such as phthalic acid, terephthalic acid,
isophthalic acid or phthalic anhydride; an
alkyldicarboxylic acid such as succinic acid, adipic acid,
sebacic acid or azelaic acid, or its anhydride; succinic
acid having a C6-18 alkyl or alkenyl group as a substituent,
or its anhydride: a known unsaturated dicarboxylic acid
such as fumaric acid, maleic acid, citraconic acid or
itaconic acid, or its anhydride, or a tri- or higher hydric
carboxylic acid such as trimellitic acid, pyromellitic acid
or benzophenonetetracarboxylic acid, or its anhydride.
Further, it may be a polyester composed solely of an
aromatic compound or an aliphatic compound. These binder
resins may be used alone or in combination as a mixture of
two or more of them.
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As the colorant, for a black colored toner, carbon
black is usually employed for a two component development.
A certain magnetic material is used for a mono component
development, and the following colorants may be employed
for a color toner. As a yellow colorant, an azo type
organic pigment such as CI pigment yellow-l, CI pigment
yellow 5, CI pigment yellow 12 or CI pigment yellow 17, or
an inorganic pigment such as Chinese yellow, or an oil-soluble
dye such as CI solvent yellow 2, CI solvent yellow
6, CI solvent yellow 14 or CI solvent yellow 19, may, for
example, be mentioned. As a magenta colorant, an azo
pigment such as CI pigment 57 or CI pigment red 57;1, a
xanthene pigment such as CI pigment violet 1 or CI pigment
81, a thioindigo pigment such as CI pigment red 87, CI vat
red 1 or CI pigment violet 38, or an oil-soluble dye such
as CI solvent red 19, CI solvent red 49 or CI solvent red
52, may, for example, be mentioned. As a cyan colorant, a
triphenylmethane pigment such as CI pigment blue 1, a
phthalocyanine pigment such as CI pigment blue 15 or CI
pigment blue 17, or an oil-soluble dye such as CI solvent
blue 25, CI solvent blue 40 or CI solvent blue 70, may, for
example, be used.
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The zirconium compound to be used in the present
invention may usually be obtained by reacting a metal-imparting
agent with a salicylic acid derivative in water
and/or an organic solvent, obtaining the product by
filtration, followed by washing. The metal-imparting agent
to be used for the preparation of this compound, may, for
example, be a halogenated zirconium compound such as ZrCl4,
ZrF4, ZrBr4 or ZrI4, an organic acid zirconium compound such
as Zr(OR)4 wherein R is hydrogen, an alkyl group or an
alkenyl group, or an inorganic acid zirconium compound such
as Zr(SO4)2, in the case of a tetravalent cationic compound.
In the case of a bivalent cationic compound of an oxo
complex, it may, for example, be an inorganic zirconium
compound such as ZrOCl2, ZrO(NO3)2, ZrO(ClO4)2, H2ZrO(SO4)2,
ZrO(SO4)Na2SO4 or ZrO(HPO4)2, or an organic zirconium
compound such as ZrO(CO3), (NH4)2ZrO(CO3)2, ZrO(C2H3O2)2,
(NH4)2ZrO(C2H3O2)3 or ZrO(C18H35O2)2.
-
Zirconium compounds represented by the formula (1) to
be used in the present invention, thus obtainable, will be
shown below.
-
For the purpose of protecting the photoreceptor or
carrier, improving the cleaning property, improving the
flowability of the toner, adjusting the thermal property,
the electrical property or the physical property, adjusting
the resistance, adjusting the softening point or improving
the fixing property, the electrophotographic toner of the
present invention may contain other additives including,
for example, hydrophobic silica, a metal soap, a fluorine
type surfactant, dioctyl phthalate, wax, a conductivity-imparting
agent such as tin oxide, zinc oxide, carbon black
or antimony oxide, or an inorganic fine powder such as
titanium oxide, aluminum oxide or alumina, as the case
requires. The inorganic fine powder to be used in the
present invention may preferably be treated with a treating
agent or a combination of various treating agents, such as
silicone varnish, various modified silicone varnishes,
silicone oil, various modified silicone oils, a silane
coupling agent, a silane coupling agent having a functional
group and other organic silicone compounds, for the purpose
of imparting hydrophobicity or controlling the tribocharge.
Further, a lubricant such as Teflon, zinc stearate or
polyvinylidene fluoride, an abrasive such as cesium oxide,
silicon carbide or strontium titanate and a caking-preventive
agent may be incorporated. Furthermore, white
fine particles and black fine particles having a polarity
opposite to toner particles may also be used in a small
amount as a developability-improving agent.
-
When the toner at the present invention is employed in
a two-component developer, it is possible to use, as the
carrier, a binder type carrier of resin particles having
fine glass beads, iron powder, ferrite powder, nickel
powder or magnetic particles dispersed therein, or a resin-coated
carrier having the surface coated with e.g. a
polyester resin, a fluorine resin, a vinyl resin, an
acrylic resin or a silicone resin. Further, a toner
containing the compound of the formula (1) according to the
present invention exhibits excellent performance also when
used as a single component toner. Furthermore, it can be
used for a capsule toner and a polymerized toner.
-
The magnetic material may, for example, be a metal fine
powder of e.g. iron, nickel or cobalt, an alloy of a metal
such as iron, lead, magnesium, antimony, beryllium, bismuth,
cadmium, calcium, manganese, selenium, titanium, tungsten,
vanadium, cobalt, copper, aluminum, nickel or zinc, a metal
oxide such as aluminum oxide, iron oxide or titanium oxide,
a ferrite of e.g. iron, manganese, nickel, cobalt or zinc,
a nitride such as vanadium nitride or chromium nitride, a
carbide such as tungsten carbide or silicon carbide, or a
mixture thereof. As the magnetic material, an iron oxide
such as magnetite, hematite or ferrite is preferred.
However, the charge control agent of the present invention
presents excellent electrification performance irrespective
of the type of the magnetic material.
-
Now, the present invention will be described in further
detail with reference to various Examples. However, it
should be understood that the present invention is by no
means restricted to such specific Examples. Further, in the
following description, "parts" means "parts by weight".
Toner for recycling
EXAMPLE 1
-
Styrene-acrylic copolymer resin (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Zirconium compound (Compound No. 1) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
EXAMPLE 2
-
Styrene-acrylic copolymer resin (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Zirconium compound (Compound No. 2) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
EXAMPLE 3
-
Styrene-acrylic copolymer resin (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Zirconium compound (Compound No. 10) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
EXAMPLE 4
-
Polyester resin (HP-301, tradename, manufactured by Nippon Gosei Kagaku K.K.) |
91 parts |
Zirconium compound (Compound No. 1) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 160°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
EXAMPLE 5
-
Polyester resin (HP-301, tradename, manufactured by Nippon Gosei Kagaku K.K.) |
91 parts |
Zirconium compound (Compound No. 2) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 160°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
EXAMPLE 6
-
Polyester resin (HP-301, tradename, manufactured by Nippon Gosei Kagaku K.K.) |
91 parts |
Zirconium compound (Compound No. 10) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 160°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
EXAMPLE 7
-
Styrene-acrylic copolymer resin (FB-1258, tradename, manufactured by Mitsubishi Rayon Co., Ltd.) |
91 parts |
Zirconium compound (Compound No. 1) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
EXAMPLE 8
-
Styrene-acrylic copolymer resin (FB-1258, tradename, manufactured by Mitsubishi Rayon Co., Ltd.) |
91 parts |
Zirconium compound (Compound No. 2) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
EXAMPLE 9
-
Styrene-acrylic copolymer resin (FB-1258, tradename, manufactured by Mitsubishi Rayon Co., Ltd.) |
91 parts |
Zirconium compound (Compound No. 10) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In both tests i.e. one with the fresh toner and
the other with the toner obtained by mixing the recovered
toner in an amount of 20 wt% to the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time.
COMPARATIVE EXAMPLE 1
-
Styrene-acrylic copolymer resin (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent (T-77, tradename manufactured by Hodogaya Chemical Co., Ltd.) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In the image test with the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time, but in the
test with the toner obtained by mixing the recovered toner
in an amount of 20 wt% to the fresh toner, a decrease in
the image density was observed, fogging tended to increase
and it was not possible to obtain a satisfactory image.
COMPARATIVE EXAMPLE 2
-
Styrene-acrylic copolymer resin (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent (Spilonblack TRH, tradename manufactured by Hodogaya Chemical Co., Ltd.) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In the image test with the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time, but in the
test with the toner obtained by mixing the recovered toner
in an amount of 20 wt% to the fresh toner, a decrease in
the image density was observed, fogging tended to increase
and it was not possible to obtain a satisfactory image.
COMPARATIVE EXAMPLE 3
-
Styrene-acrylic copolymer resin (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent (Borotoron E-84, Tradename, manufactured by Orient Chemical Co., Ltd.) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In the image test with the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time, but in the
test with the toner obtained by mixing the recovered toner
in an amount of 20 wt% to the fresh toner, a decrease in
the image density was observed, fogging tended to increase
and it was not possible to obtain a satisfactory image.
COMPARATIVE EXAMPLE 4
-
Polyester resin (HP-301, tradename, manufactured by Nippon Gosei Kagaku K.K.) |
91 parts |
Charge control agent (T-77, tradename, manufactured by Hodogaya Chemical Co., Ltd. |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 160°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In the image test with the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time, but in the
test with the toner obtained by mixing the recovered toner
in an amount of 20 wt% to the fresh toner, a decrease in
the image density was observed, fogging tended to increase
and it was not possible to obtain a satisfactory image,
COMPARATIVE EXAMPLE 5
-
Polyester resin (HP-301, tradename, manufactured by Nippon Gosei Kagaku K.K.) |
91 parts |
Charge control agent (Spilonblack TRH, Tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 160°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In the image test with the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time, but in the
test with the toner obtained by mixing the recovered toner
in an amount of 20 wt% to the fresh toner, a decrease in
the image density was observed, fogging tended to increase
and it was not possible to obtain a satisfactory image.
COMPARATIVE EXAMPLE 6
-
Polyester resin (HP-301, tradename, manufactured by Nippon Gosei Kagaku K.K.) |
91 parts |
Charge control agent (Borotoron E-84, tradename, manufactured by Orient Chemical Co., Ltd. |
1 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 160°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus, and the
electrification distribution was measured by an E-SPART
analyzer. Further, an image test by a modified commercial
copying machine was also carried out. Firstly, a running
test up to 50,000 sheets was carried out in a system where
no recycling of the toner was carried out. Further, using a
toner obtained by mixing the toner recovered from the above
test in an amount of 20 wt% to a fresh toner, the blow off
charge measurement and the electrification distribution
measurement were carried out under the same conditions as
the above methods. Further, using this toner, an image test
up to 50,000 sheets was carried out. The results are shown
in Table 2. In the image test with the fresh toner, a
sufficient image density was obtained, no fogging or
scattering in the machine was observed, and a high quality
image was obtained over a long period of time, but in the
test with the toner obtained by mixing the recovered toner
in an amount or 20 wt% to the fresh toner, a decrease in
the image density was observed, fogging tended to increase
and it was not possible to obtain a satisfactory image.
Example No. | Resin (tradename) | Charge control agent | Evaluation of toner |
| | | Charge 1 (µC/g) | Charge 2 (µC/g) | In recycling |
| | | | | Image density | Fogging | Scattering of toner |
| | | Initial 50,000 sheets | Initial 50,000 sheets | Initial 50,000 sheets | Initial 50,000 sheets | Initial 50,000 sheets |
1 | SA | Compound | -23.5 | -23.2 | ○ | ○ | ○ |
(CPR-100) | No. 1 | -23.0 | -23.5 | ○ | ○ | ○ |
2 | SA | Compound | -22.6 | -22.8 | ○ | ○ | ○ |
(CPR-100) | No. 2 | -22.2 | -22.2 | ○ | ○ | ○ |
3 | SA | Compound | -23.5 | -23.1 | ○ | ○ | ○ |
(CPR-100) | No. 10 | -22.9 | -22.2 | ○ | ○ | ○ |
4 | PE | Compound | -25.2 | -23.9 | ○ | ○ | ○ |
(HP-301) | No. 1 | -23.5 | -24.9 | ○ | ○ | ○ |
5 | PE | Compound | -24.7 | -24.2 | ○ | ○ | ○ |
(HP-301) | No. 2 | -24.1 | -22.7 | ○ | ○ | ○ |
6 | PE | Compound | -24.0 | -23.2 | ○ | ○ | ○ |
(HP-301) | No. 10 | -24.2 | -23.8 | ○ | ○ | ○ |
7 | SA | Compound | -22.8 | -23.8 | ○ | ○ | ○ |
(FB-1258) | No. 1 | -22.0 | -22.8 | ○ | ○ | ○ |
8 | SA | Compound | -22.4 | -21.2 | ○ | ○ | ○ |
(FB-1258) | No. 2 | -22.2 | -22.9 | ○ | ○ | ○ |
9 | SA | Compound | -22.0 | -21.2 | ○ | ○ | ○ |
(FB-1258) | No. 10 | -21.9 | -22.3 | ○ | ○ | ○ |
Comparative Example 1 | SA | T-77 | -12.3 | -10.5 | ▵ | ▵ | ○ |
(CPR-100) | -8.3 | -5.3 | ▵ | ▵ | ○ |
Comparative Example 2 | SA | TRH | -13.3 | -11.4 | ▵ | X | ▵ |
(CPR-100) | -9.3 | -4.3 | ▵ | X | ▵ |
Comparative Example 3 | SA | E-84 | -22.3 | -15.5 | X | X | X |
(CPR-100) | -10.3 | -4.8 | X | X | X |
Comparative Example 4 | PE | T-77 | -15.3 | -11.2 | ○ | ○ | ○ |
(HP-301) | -10.3 | -7.8 | ▵ | ▵ | ▵ |
Comparative Example 5 | PE | TRH | -14.3 | -14.1 | ▵ | ▵ | ▵ |
(HP-301) | -13.3 | -8.7 | ▵ | X | ▵ |
Comparative Example 6 | PE | E-84 | -21.3 | -19.3 | X | X | ▵ |
(HP-301) | -17.3 | -10.5 | X | X | ▵ |
Charge 1 represents the blow off charge of the fresh toner, and charge 2 represents the
blow off charge of the toner obtained by mixing the waste toner in an amount of 20 wt% to
the fresh toner. |
-
In the evaluation of image density, symbol ○ represents
"sufficient image density", symbol ▵ represents "fair image
density" and symbol X represents "insufficient image
density". In the evaluation of fogging, symbol ○
represents "no fogging", symbol ▵ represents "slight
fogging", and symbol X represents "substantial fogging".
In the evaluation of scattering of toner, symbol ○
represents "no scattering", symbol ▵ represents "slight
scattering", and symbol X represents "substantial
scattering".
Combined toner with an azo metal complex
EXAMPLE 11
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No, 1) |
(0.05 part) |
T-77 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.95 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 12
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.10 part) |
T-77 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.90 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 13
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.50 part) |
T-77 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.50 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 14
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.80 part) |
T-77 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.20 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 15
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.05 part) |
Spilonblack TRH (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.95 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 16
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.10 part) |
Spilonblack TRH (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.90 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 17
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.50 part) |
Spilonblack TRH (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.50 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 18
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.80 part) |
Spilonblack TRH (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.20 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 19
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.05 part) |
T-95 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.95 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 20
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.10 part) |
T-95 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.90 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 21
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.50 part) |
T-95 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.50 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
EXAMPLE 22
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.80 part) |
T-95 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.20 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was excellent, and a sufficient image density was
obtained under all conditions. A high quality image with
sufficient reproducibility of a fine line was obtained over
a long period of time without fogging.
COMPARATIVE EXAMPLE 8
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Zirconium compound (Compound No. 1) |
1.0 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was good, but no adequate image density was
obtained when 50,000 sheets were copied.
COMPARATIVE EXAMPLE 9
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent (T-77, tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
1.0 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture containing only T-77 as the charge
control agent was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and roughly
pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was poor, and no adequate image density was
obtained at the initial stage of printing.
COMPARATIVE EXAMPLE 10
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent (Spilonblack TRH, tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
1.0 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture containing only Spilonblack TRH as
the charge control agent was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was poor, and no adequate image density was
obtained at the initial stage of printing.
COMPARATIVE EXAMPLE 11
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent (T-95, tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
1.0 part |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture containing only T-95 as the charge
control agent was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and roughly
pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was poor, and no adequate image density was
obtained at the initial stage of printing.
COMPARATIVE EXAMPLE 12
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.03 part) |
T-77 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.97 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was poor, and no adequate image density was
obtained at the initial stage of printing.
COMPARATIVE EXAMPLE 13
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
91 parts |
Charge control agent |
1 part |
Zirconium compound (Compound No. 1) |
(0.85 part) |
T-77 (tradename, manufactured by Hodogaya Chemical Co., Ltd.) |
(0.15 part) |
Carbon black (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
5 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized by a jet mill and then classified to obtain a
black toner having a particle size of from 10 to 12 µm.
This toner was mixed with a silicon coated ferrite carrier
(F96-100, tradename, manufactured by Powder Tech Co.) in a
weight ratio of 4:100, and the mixture was shaked to
negatively electrify the toner. Then, the charge was
measured by a blow off charge measuring apparatus. Further,
the electrification rising property was compared by the
time constant. Further, an image test by a modified
commercial copying machine was also carried out. The
results are shown in Table 3. The electrification rising
property was poor, and no adequate image density was
obtained at the initial stage of printing.
-
In the evaluation of image quality, symbol ○ represents
"sufficient image quality", and symbol ▵ represents "fair
image quality". In the evaluation of environmental
stability, symbol ○ represents "safe". In the evaluation
of fogging or scattering of toner, symbol ○ represents "no
fogging or scattering of toner", and symbol ▵ represents
"slight fogging or slight scattering of toner".
Magnetic toner
EXAMPLE 23
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force: 60 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
80 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 28 Am2/kg, and the coercive
force was 60 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. The electrification rising property was
excellent, and a sufficient image density was obtained
under all conditions. A high quality image with sufficient
reproducibility of fine lines was obtained over a long
period of time without fogging.
EXAMPLE 24
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force: 90 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
80 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 28 Am2/kg, and the coercive
force was 90 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. The electrification rising property was
excellent, and a sufficient image density was obtained
under all conditions. A high quality image with sufficient
reproducibility of fine lines was obtained over a long
period of time without fogging.
EXAMPLE 25
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force: 140 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
80 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 28 Am2/kg, and the coercive
force was 140 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. The electrification rising property was
excellent, and a sufficient image density was obtained
under all conditions. A high quality image with sufficient
reproducibility of fine lines was obtained over a long
period of time without fogging.
EXAMPLE 26
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
1 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force; 180 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
80 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 28 Am2/kg, and the coercive
force was 180 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. The electrification rising property was
excellent, and a sufficient image density was obtained
under all conditions. A high quality image with sufficient
reproducibility of fine lines was obtained over a long
period of time without fogging.
EXAMPLE 27
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force: 140 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
100 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 32 Am2/kg, and the coercive
force was 140 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. The electrification rising property was
excellent, and a sufficient image density was obtained
under all conditions. A high quality image with sufficient
reproducibility of fine lines was obtained over a long
period of time without fogging.
EXAMPLE 28
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force: 140 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
120 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 36 Am2/kg, and the coercive
force was 140 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. The electrification rising property was
excellent, and a sufficient image density was obtained
under all conditions. A high quality image with sufficient
reproducibility of fine lines was obtained over a long
period of time without fogging.
EXAMPLE 29
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force: 90 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
100 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 32 Am2/kg, and the coercive
force was 90 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. The electrification rising property was
excellent, and a sufficient image density was obtained
under all conditions. A high quality image with sufficient
reproducibility of fine lines was obtained over a long
period of time without fogging.
EXAMPLE 30
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force; 90 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
120 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 36 Am2/kg, and the coercive
force was 90 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. The electrification rising property was
excellent, and a sufficient image density was obtained
under all conditions. A high quality image with sufficient
reproducibility of fine lines was obtained over a long
period of time without fogging.
COMPARATIVE EXAMPLE 14
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force: 300 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
80 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 28 Am2/kg, and the coercive
force was 300 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. By repeated printing operation for a long
period of time, a decrease in the image density was
observed. Further, at the same time, fogging was observed,
and a distinct image deterioration was observed.
COMPARATIVE EXAMPLE 15
-
Styrene-acrylic copolymer resin (acid value: 0.1) (CPR-100, tradename, manufactured by Mitsui Chemical Co., Ltd.) |
100 parts |
Zirconium compound (Compound No. 1) |
2 parts |
Magnetic powder (average particle size: 0.2 µm, coercive force: 90 oersted) (MA-100, tradename, manufactured by Mitsubishi Chemical Corporation) |
150 parts |
Low molecular weight polypropylene (Biscoal 550P, tradename, manufactured by Sanyo Kasei K.K.) |
3 parts |
-
The above mixture was melted and kneaded by a heat-mixing
apparatus at 140°C, and the mixture was cooled and
roughly pulverized by a hammer mill. It was further finely
pulverized and then classified to obtain a black toner
having a particle size of from 10 to 12 µm. The saturation
magnetization of this toner was 52 Am
2/kg, and the coercive
force was 90 oersted. This toner was mixed with a silicon
coated ferrite carrier (F96-100, tradename, manufactured by
Powder Tech Co.) in a weight ratio of 4:100, and the
mixture was shaked to negatively electrify the toner. Then,
the charge was measured by a blow off charge measuring
apparatus. Further, an image test by a modified commercial
copying machine was also carried out. The results are shown
in Table 4. From the image of the initial stage, formation
of a ghost due to fixing failure or soiling of the fixing
roller was observed. Further, by repeated printing
operation for a long period of time, the image density
decreased. At the same time, fogging was observed, and a
distinct image deterioration was observed.
Example No. | Saturation magnetization | Coercive force | Evaluation of toner |
| | | Charge (µC/g) | Image quality | Fixing property | Fogging Scatterring of toner |
| | | Initial | After 50,000 sheets | Initial | After 50,000 sheets |
23 | 28 | 60 | -18.0 | -18.2 | ○ | ○ | ○ | ○ |
○ |
24 | 28 | 90 | -17.6 | -17.5 | ○ | ○ | ○ | ○ |
○ |
25 | 28 | 140 | -18.5 | -18.2 | ○ | ○ | ○ | ○ |
○ |
26 | 28 | 180 | -19.7 | -21.2 | ○ | ○ | ○ | ○ |
○ |
27 | 32 | 140 | -16.5 | -15.4 | ○ | ○ | ○ | ○ |
○ |
28 | 36 | 140 | -15.6 | -15.3 | ○ | ○ | ○ | ○ |
○ |
29 | 32 | 90 | -16.8 | -16.8 | ○ | ○ | ○ | ○ |
○ |
30 | 36 | 90 | -15.2 | -15.6 | ○ | ○ | ○ | ○ |
○ |
Comp. Ex. 14 | 28 | 300 | -19.2 | -23.5 | ○ | X | X | ▵ |
▵ |
Comp. Ex. 15 | 52 | 90 | -13.4 | -12.7 | X | X | ○ | X |
X |
-
In the evaluation of image quality, symbol ○ represents
"sufficient image quality", and symbol X represents
"insufficient image quality". In the evaluation of fixing
property, symbol ○ represents "good fixing property", and
symbol X represents "poor fixing property".
In the evaluation of fogging or scattering of toner,
symbol ○ represents "no fogging or scattering of toner",
symbol ▵ represents "slight fogging or slight scattering of
toner", and symbol X represents "substantial fogging or
substantial scattering of toner".
-
The zirconium compound of the formula (1) to be used in
the present invention is a colorless or slightly colored
thermally stable compound which can be uniformly dispersed
in a binder resin, and thus it always presents an image of
high quality even when it is used in a recycling system.
-
Further, the zirconium compound of the formula (1) to
be used in the present invention is a colorless or slightly
colored highly stable compound, and by using it in
combination with a specific azo metal complex, it is
possible to present an electrostatic image developing toner
having an extremely quick electrification rising property,
whereby it is possible to always present an image of high
quality from the initial stage of printing.
-
Furthermore, by the magnetic toner employing the
zirconium compound of the formula (1) to be used in the
present invention, it has been made possible to present an
electrostatic image developing toner which is excellent in
the electrification rising property and which is capable of
presenting an image of a sufficient image quality under all
conditions.