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Description  |
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FIELD OF THE INVENTION
The present invention relates to a plastic film improved in its antistatic
property so as to be less affected by the change of humidity. It can be
used for a magnetic tape, a floppy disk, a flexible board, a substrate for
a membrane switch and a recording sheet for a printer. Since a film
transparent sufficiently can be made, it can be used for an OHP film, a
liquid crystal display apparatus, a touch panel and a stained glass. In
addition, it can also be used for a photographic light-sensitive material
because the excellent degree of clearness of the plastic film does not
adversely affect the photographic characteristics of the photographic
light-sensitive material.
BACKGROUND OF THE INVENTION
Because of commonly strong static charge build-up, plastic films have been
hitherto often limited in their use other than the use taking advantage of
such properties. For example, light-sensitive photographic materials
commonly make use of plastic film as a support having electrical
insulation properties. Such materials belong to what is called composite
materials, comprised of a support and a light-sensitive photographic
material layer. Hence the light-sensitive photographic materials tend to
be statically charged when, during their manufacture and use, they come
into contact with the surface of a material of the same or different kind
or they are separated therefrom. Most static charges accumulated as a
result of static charging cause various difficulties. The most important
difficulty is what is called static marks, which are spots or branch-type
or feather-type lines occurring during the photographic processing of the
light sensitive photographic materials whose light-sensitive silver halide
emulsion layers have been sensitized as a result of the discharge of
static electricity accumulated before the photographic processing. When,
for example, this phenomenon occurs in medical or industrial X-ray films,
it leads to a very dangerous determination. This phenomenon becomes known
only when the photographic films have been processed, and is one of very
difficult problems. These accumulated static charges may also cause
troubles such that dust adheres to a plastic film surface and no uniform
coating on the film surface can be carried out.
Such troubles caused by static charging may also occur in many cases
besides the foregoing. For example, in the course of manufacture, the
troubles may be caused by contact friction between photographic films and
rollers and by separation of emulsion sides from support sides in the
course of winding-up or unwinding of photographic films. In finished
products, the troubles may be caused by separation of emulsion sides from
base sides when photographic films are wound up and changeover is made,
and by contact and separation occurring between X-ray films and machine
parts during automatic photographing or between X-ray films and
intensifying screens. The troubles may also be caused by contact with
other packaging materials. The static marks of light-sensitive
photographic materials, caused by accumulation of such static charges
become remarkable with an increase in sensitivity of light-sensitive
photographic materials and an increase in processing speed thereof. In
particular, in these days, static marks tend to occur since photographic
materials have been made to have a higher sensitivity and are often
handled under severe conditions such that light-sensitive coating is
carried out at a higher speed, or photographs are taken at a higher speed
and automatic processing is carried out at a higher speed.
Moreover, in recent years, adhesion of dust after photographic processing
has come into question, and it is sought to make an improvement so that
antistatic properties can also be retained after the processing.
The best method for eliminating such difficulties due to static is to
increase electrical conductivity of substances so that static charges can
be dissipated in a short time before the discharge of accumulated
electricity takes place.
Accordingly, methods of improving the conductivity of supports of
light-sensitive photographic materials or that of surface layers of
various coatings have been hitherto proposed and it has been attempted to
utilize various hygroscopic substances and water -soluble inorganic salts
and certain types of surface active agents and polymers. For example,
Japanese Patent Publications Open to Public Inspection [hereinafter
referred to as Japanese Patent O.P.I. Publication(s)] No. 91165/1974 and
No. 121523/1974 disclose examples in which ion type polymers having a
dissociative group in the polymer main chain are applied. Other invention
is also known which relates to conductive polymers as disclosed in
Japanese Patent O.P.I. Publications No. 9689/1990 and No. 182491/1990 and
surface active agents as disclosed in Japanese Patent O.P.I. Publications
No. 55541/1988, No. 148254/1988, No. 148256/1988 and No. 314191/1989.
These many substances, however, have a specificity depending on the types
of film supports and the difference in photographic compositions and can
give good results on certain types of film supports, photographic
emulsions and photographic components. They, however, not only can be of
no use at all for antistatic in the case of other different types of film
supports and photographic components, but also may adversely affect
photographic performance. Another important disadvantage thereof is that
most of these substances Lose their function as a conductive layer when
used in an environment of a low humidity.
For the purpose of preventing the deterioration of performance in an
environment of low humidity, Japanese Patent Examined Publications No.
6616/1960 and No. 20735/1989 disclose techniques in which metal oxides are
used as antistatic treatments. The former discloses a method in which a
colloidal sol dispersion is used. The latter discloses a method in which a
highly crystalline metal oxide powder having been treated at a high
temperature is used so that a problem concerning conductivity in the
former can be eliminated. In the latter technique, however, it is stated
that because of the use of a highly crystalline powder its particle
diameter, the ratio of particles to a binder, etc. must be taken into
account as countermeasures to the scatter of light. Japanese Patent O.P.I.
Publication No. 29134/1992 also discloses a method in which a particulate
metal oxide and a fibrous metal oxide are employed in conductive materials
used in light-sensitive photographic materials for the purpose of not only
improving performance in an environment of low humidity but also
eliminating other disadvantages. There, however, have remained a problem
concerning the amount of the oxides added.
Thus, in relation to light-sensitive photographic materials provided with a
layer containing conductive fine metal particles , problems have remained
unsettled yet even though means for preventing the deterioration of
performance in an environment of low humidity have been studied for 30
years or more since the above techniques were disclosed in Japanese Patent
Examined Publication No. 6616/1960.
For example, in the case when a layer containing such conductive fine metal
particles is provided adjoiningly to a silver halide layer containing
silver halides, there is the problem that pressure marks or abrasion marks
tend to occur in images as a result of any friction caused when
light-sensitive photographic materials are handled. For another example,
in the case when such particles are used as a mixture with a binder, there
is the problem that fine particles present on the surface of light
sensitive photographic materials may fall as a result of any friction
caused when light-sensitive photographic materials are manufactured or
handled, and hence may adhere to rollers in the course of the manufacture
to scratch the products being carried. In addition, materials mainly
composed of these metal elements generally have a high specific gravity.
Accordingly, when they are coated on a photographic light-sensitive
material, problems such as precipitation of fine particles are caused,
resulting in an adverse effect on uniformity of a coating solution and
preservability.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is provide a plastic film
material or a photographic light-sensitive material wherein pressure
fogging and scratches are not caused, transparency is excellent and a high
antistatic property can be kept even under a low humidity condition.
The above object of the invention has been attained by a plastic film
material comprising particles comprised of 70% or more by weight of a
compound consisting of an element selected from H, B, C, N, O, F, P, S and
C1, said particles having a volume specific resistance of 10.sup.9
.OMEGA.cm or less.
The above object of the invention has been attained preferably by a plastic
film material comprising particles having a volume specific resistance of
not more than 10.sup.9 .OMEGA.cm and comprised of 70% or more by weight of
a compound represented by the following formula (I):
##STR1##
wherein X and X' each represent a group selected from --O--, --NH-- and
--NR"--; R, R' and R" each represent a group comprising at least one
element selected from H, B, C, N, O, F, P, S or Cl; and n is an integer of
3 or more, provided that a+b=2, wherein a and b each represent a positive
number.
It is preferable that R, R' and R" each represent an organic group.
The plastic film material of the invention preferably comprises particles
comprised of 70% or more by weight of an electron or ion conductive
polymer, and this invention may preferably comprise particles comprised of
70% or more by weight of a carbon material. The particles preferably have
an average particle diameter of 1 .mu.m or less and/or have a specific
gravity of 3.0 or less.
The plastic film material of the present invention is most preferably used
as a support for a photographic film. On such occasion, it has a
noticeable effect of the present invention.
This represents that the material of the present invention has solved the
above-mentioned existing problems by incorporating specific fine particles
in which the main components are not a metal element.
The present invention can be used for a magnetic tape, a floppy disk, a
flexible board, a substrate for a membrane switch and a recording sheet
for a printer. Since a film transparent sufficiently can be offered, it
can be used for an OHP film, a liquid crystal display apparatus, a touch
panel and a stained glass. In addition, it can also be used for a
photographic light-sensitive material because the excellent degree of
clearness of the plastic film does not adversely affect the photographic
characteristics of the photographic light-sensitive material.
As known in the art, the conductivity of these metal oxide powders is
exhibited by charge carriers such as cations, anions or electrons or
positive holes present in oxides. The total electrical conductivity
thereof (or) is expressed as follows:
.sigma.t=.sigma.c+.sigma.a+.sigma.n+.sigma.p
wherein;
.sigma.c is electrical conductivity of cations;
.sigma.a is electrical conductivity of anions;
.sigma.n is electrical conductivity of electrons;
.sigma.p is electrical conductivity of positive holes.
When the charge carriers are mainly ions, a solid electrolyte is formed.
When the charge carriers are electrons, semiconductors are formed. In
usual instances, conductors comprised of a mixture of the both are formed,
and non-stoichiometric compounds such as oxygen-deficient oxides,
metal-excess oxides, metal-deficient oxides and oxygen-excess oxides are
formed as semiconductors. While the conductivity of many conductive
materials is exhibited in the above-mentioned manner, many of conductive
or semi-conductive materials have metallic elements as the main
components, resulting in the high specific gravity. Accordingly, compounds
which are metallic oxides having volume specific resistance of 10.sup.9
.OMEGA.cm or less have so far caused a problem of an uneven coating
solution because their precipitation speed is high when they are used as
an antistatic material for a transparent film, though they have excellent
optical properties.
The present inventors have studied the structure, the constitution elements
and the characteristics of conductive or semi-conductive materials to
reach the following conclusions for achievement of the present invention.
(1) If the main components of fine particles are non-metallic elements, a
specific gravity is lowered so that the problem of precipitation can be
solved.
(2) Generally, when a non-metallic element is the main component,
conductivity is lowered. However, some materials having non-localized
electrons or having an ionic group can make fine particles whose volume
specific resistance is not more than 10.sup.9 .OMEGA.cm.
(3) When conductive or semi-conductive materials are mixed with
semi-conductive or insulating materials for producing fine particles, fine
particles whose volume specific resistance is not more than 10.sup.9
.OMEGA.cm can be produced.
(4) When the specific gravity of material is smaller than a certain
specific gravity, the problem of precipitation can be solved even when the
specific gravity of the dispersed fine particles are larger than that of
the dispersion medium or the average particle diameter is about 1 .mu.m.
Thus, they have reached the present invention.
Namely, the present inventors invented a plastic film material or a silver
halide photographic light-sensitive material with improved antistatic
properties and excellent optical characteristics containing fine particles
whose volume specific resistance is not more than 10.sup.9 .OMEGA.cm and
whose main component is non-metallic element.
With regard to volume specific resistance, the volume specific resistance
of a large single crystal means that of the crystal itself. When a large
single crystal is obtained, the volume specific resistance of powder or
particles, which are not a single crystal, means that of a material molded
under a pressure from the powder or particles. When volume specific
resistance is unknown, the value is represented by that obtained by
dividing volume specific resistance of a material molded from powder under
a specific pressure with 10.sup.2. There is no limitation to the value of
specific pressure. However, it is preferably 10 kg/cm.sup.2 or more, and
more preferably 100 kg/cm.sup.2 or more. In general, relation between
pressure applied to powder and volume specific resistance of the molded
material tends that, the higher the pressure is, the lower the volume
specific resistance is. However, even when an isotropic pressure of 3
t/cm.sup.2 is applied by means of a static water pressure type pressurer,
a value lower than the volume specific resistance obtained in a single
crystal cannot be obtained. The value becomes higher by about 100 times.
Accordingly, a value of the volume specific resistance of a molded
material obtained from powder by means of a specific pressure divided by
10.sup.2 is adopted. The volume specific resistance of the invention is a
value obtained by measuring at 25.degree. C. and 20% RH.
In general, a semiconductor material is defined to be a material having a
volume specific resistance of less than 10.sup.12 .OMEGA.cm, and a
conductor material is defined to be a material having a volume specific
resistance of less than 10.sup.12 .OMEGA..
Any fine particles can be used for the present invention provided that a
volume specific resistance of the main components thereof is not more than
10.sup.9 .OMEGA.cm and the main components are non-metallic elements.
Namely, the fine particles may be structured by a single material in which
a non-metallic element is the main component or may be combined with other
kind of materials. In addition, the structure of the fine particles may be
crystalline or amorphous. The higher order structure may have an inclined
composition, regular composition distribution, uneven distribution or the
like provided that the structure and the object of the present invention
are attained.
For example, fine particles composed of an organic or inorganic polymer
having an ionic group and conductive or semi-conductive organic or
inorganic polymer having a non-localized electron, mixed fine particles of
the above-mentioned materials and materials containing minute amount of
metallic element and fine particles containing a non-metallic conductive
material such as carbon or a semi-conductive material are cited.
More particularly, it can be illustrated that the basic skeleton of the
compound constituting the above-mentioned fine particles is composed of a
phosphazene derivative comprising a P.dbd.N bond and that a part of a
substituent is an ionic side chain group, a .pi. electron type side chain
group of a compound which offers conductivity and a polyether side chain
group. These compounds include a linear compound or cyclic compound with a
high molecular weight having a P.dbd.N bond. The linear compound is
generally synthesized by a ring-opening polymerization of a cyclic
compound. It is preferable that, due to its special synthesis method, a
cyclic compound can be synthesized at lower cost. The synthesis method of
the above-mentioned cyclic compound will be described further in detail.
Reactions of a halogen atom in a trimer, a tetramer and an n-mer compound
wherein a side chained group such as (PNF.sub.2).sub.3, (PNF.sub.2).sub.4
or (PNF.sub.2)n (N<15) is an F atom, a halogen atom in a trimer, a
tetramer and an n-mer compound wherein a side chained group such as
(PNCl.sub.2).sub.3, (PNCl.sub.2).sub.4 or (PNCl.sub.2).sub.n (N<15) is a
Cl atom, a halogen atom in a trimer, a tetramer and an n-mer compound
wherein a side chained group such as (PNBr.sub.2).sub.3,
(PNBr.sub.2).sub.4 or (PNBr.sub.2)n (N<15) is an Br atom and a halogen
atom in a trimer, a tetramer and an n-mer compound wherein a side chained
group such as (PNI.sub.2).sub.3, (PNI.sub.2).sub.4 or (PNi.sub.2).sub.n
(N<15) is an I atom on a metallic salt of an aromatic organic compound
such as C.sub.6 H.sub.5 ONa, CH.sub.3 C.sub.6 H.sub.4 ONa, (C.sub.6
H.sub.5 O).sub.2 Ca and CF.sub.3 CH.sub.2 ONa and mixtures of aromatic
group compounds having a hydroxyl group such as C.sub.6 H.sub.5 OH or
aliphatic group compounds which can conduct nucleophilic substitution with
a halogen atom on a P atom such as an aliphatic alcohol such as CH.sub.2
(CH.sub.3).dbd.C--COOCH.sub.2 CH.sub.2 OH and aromatic amines such as
C.sub.6 H.sub.5 NH.sub.2 with a chlorine accepting compound such as amines
such as aniline, sodium hydroxide and potassium carbonate can be cited.
Phosphagene derivatives are generally synthesized in the above-mentioned
manner. However, a synthesis method including a substituting reaction
mainly is not limited especially.
The side chain group of an aromatic group is generally defined to be a
group derived from a compound having an aromatic group ring.
##STR2##
wherein R.sub.1 represents a hydrogen atom, a halogen atom, an alkyl group
or an alkoxy group, and groups derived from compounds having a hydroxyl
group as a functional group on an aromatic group ring such as
##STR3##
are cited.
In addition, groups derived from compounds having an amino group on an
aromatic group ring such as aniline and phenylene diamine as a functional
group or groups derived from compounds having a mercapto group on an
aromatic group ring such as thiophenol and dimercaptobenzene as a
functional group are cited. These aromatic groups may have a sulfonic
group. In addition, a combination of a side-chained group is not
necessarily composed of a single group. A combination of several groups
selected therefrom is allowed. Compounds represented by the
above-mentioned formula (I) synthesized by the above-mentioned synthesis
method are further preferable. It is preferable that R, R' and R" of the
formula (I) is aromatic groups simultaneously.
In addition, conjugated polymers such as tetracyanoquinoedimethane (TCNQ),
tetrathiofurbalene, polyacetylene (TTF), coterylene, polyparaphenylene,
polythiophene, polypyrrol and polyaniline, polymers to which a suitable
dopant is doped and compounds composed of an ionic conductive polymers
such as polyvinyl benzene sulfonates, polyvinyl benzyltrimetyl ammonium
chloride and quaternary salt polymers can also be used.
In addition, fine particles wherein a carbon material is dispersed in an
organic polymer and hardened can be used. With regard to carbon materials,
materials produced by means of a carbonating process with an organic
compound as a starting raw material including coke, carbon fiber, glass
carbon, thermal-decomposed carbon, whisker and carbon black are cited.
Carbon materials include various types depending upon their raw materials.
The main components of their structuring elements occupying 90 wt % or
more are C, O, H and N in this order from larger %. When the C component
contained in compounds is 70 wt % or more, the object of the present
invention can be attained.
With regard to a particle diameter of the particles wherein the component
of 70 wt % or more is selected from H, B, C, N, O, F, P, S and Cl, the
average particle size is not more than 10 .mu.m in terms of smoothness,
preferably not more than 1 .mu.m, and more preferably 0.001 to 1.0 .mu.m.
Though there is no limitation to the measurement method of average
particle size, a method wherein fine particles are dispersed in a suitable
solvent and an average particle diameter calculated from a centrifuged
precipitation speed is generally adopted. However, the average particle
diameter may be calculated through electron micrograph of samples sampled
randomly from powder containing fine particles composed of elements
selected from H, B, C, N, O, F, P, S and Cl. In addition, there are many
methods of measurement for an average particle diameter other than the
methods described here. Any method can be used.
With regard to a specific gravity of fine particles constituted of elements
selected from H, B, C, N, O, F, P, S and Cl, a measurement method capable
of offering a specific gravity nearest that of the material constituting
the fine particle is selected. For example, a method wherein, after weight
is measured by a chemical balance, the volume of a fine particle is
measured by the use of suitable gas or fluid for calculating the specific
gravity is ordinarily used. In the present invention, no special
limitation is placed on the measurement method of specific gravity.
However, the value of the specific gravity of fine particles whose main
component is constituted of elements selected from H, B, C, N, O, F, P, S
and Cl is preferably 3.0 or less with water at 20.degree. C. as a standard
and more preferably, 0.6 to 3.0, in order to avoid a problem of the
precipitation of particles in a coating solution.
As a method for producing conductive or semi-conductive particles, any
conventional synthesizing methods can be used as far as they can attain
the object of the present invention. Any methods capable of attaining the
object of the present invention such as, for example, a method to produce
fine particles by the use of a spray drying after a compound is dissolved
in a suitable solvent, a method to crush a compound with a ball mill and a
sand grinder after being dissolved in a solvent, a method to crush a
compound by means of a drying type crusher such as a jet mill or to
separate the compound into two phases, i.e. a solvent phase and a produced
material phase, in manufacturing the compound and a method make particles
fine by the use of method to produce a compound in condition that the
compound has been separated into two or more phases in advance can be
used. In addition, though a method to produce fine particles while a
conductive layer is coated and dried is allowed, a method to disperse
conductive fine particles stably at the stage of coating and forming a
conductive phase.
The above-mentioned particles and conductive polymer compounds are
dispersed and dissolved in a binder. Or, powder wherein metal oxidized
particles were subjected to surface treatment with an electroconductive
polymer or microcapsulating or a powder, after mixing in medium wherein
metal oxidized particles are dissolved or dispersed in an
electroconductive polymer, subjected to a spray dry method or a freezing
drying method may be dispersed and coated.
The added amounts of particles and electroconductive polymer compound are
explained as follows: The electroconductive polymer compound are added in
an extent that does not deteriorate the physical properties such as
electroconductivity. There is no limitation thereto. With regard to the
added amount of the particles of the invention, it is ordinarily not more
than 60%, preferably not more than 50% and especially preferably not more
than 40% in terms of volume fraction. However, it is preferable as the
added amount is smaller. The powder is preferably added in a volume
fraction of not more than 30%. It may more preferably be in a volume
fraction of not more than 20%. However, it is necessary to add in terms of
a volume fraction of not less than 0.1% and preferably not less than 0.5%.
Some compounds may require its addition in a volume fraction of not less
than 1%. However, with regard to added amount, there is no especial
limitation in the present invention.
According to this volume fraction, the amount used comes to be reduced to
approximately from 0.00005 to 1 g per square meter of a light-sensitive
photographic material, so that a desirable transparency and a higher
antistatic can be achieved. Hence the electroconductive material can be
obtained, and the pressure marks and abrasion marks can be prevented from
occurring when light-sensitive photographic materials are handled. In
addition, in the case of the above-mentioned added amount, the surface
specific resistance of a film obtained in the present invention is less
than 10.sup.13 .OMEGA.cm so that the antistatic of a film can be attained.
There are no particular limitations on the binder used in the present
invention so long as it is capable of forming a film. For example, the
binder may include proteins such as gelatin and casein, cellulose
compounds such as carboxymethyl cellulose, hydroxyethyl cellulose, acetyl
cellulose, diacetyl cellulose and triacetyl cellulose, saccharides such as
dextran, agar, sodium alginate and starch derivatives, and synthetic
polymers such as polyvinyl alcohol, polyvinyl acetate, polyacrylates,
polymethacrylates, polystyrene, polyacrylamide, poly-N-vinyl pyrrolidone,
polyester, polyvinyl chloride and polyacrylic acid.
In particular, it is preferred to use gelatin such as lime-treated gelatin,
acid-treated gelatin, enzymolyzed gelatin, phthalated gelatin or
acetylated gelatin, acetyl cellulose, diacetyl cellulose, triacetyl
cellulose, polyvinyl acetate, polyvinyl alcohol, polybutyl acrylate,
polyacrylamide, or dextran.
As a dispersion method of a conductive substance or semiconductor grains
into a binder, a method to utilize free rotation movement, a method to
utilize hindrance movement inside a vessel provided with a hindrance
plate, a method to utilize tilting movement wherein a sealed vessel is
rotated around the horizontal axis, a method to shake a vessel upward and
downward and a method to utilize cutting strength on a roll. Any method
may be chosen as far as not preventing the object of the present
invention. It is preferable, in one of these method, to mix a conductive
substance or semiconductor grains. For example, a method to utilize
rotation movement wherein grains having a size of 0.1 mm or larger and a
method using a sand grinder are cited.
The plastic film material that can be used in the present invention may
include, for example, cellulose nitrate film, cellulose acetate film,
cellulose acetate butyrate film, cellulose acetate propionate film,
polystyrene film, polyethylene terephthalate film and polycarbonate film,
as well as laminates of any of these.
These plastic film materials can be used as a support of a silver halide
photographic light-sensitive material and may be appropriately selected
from transparent supports and opaque supports according to the purpose for
which light-sensitive photographic materials are used. The transparent
supports are not limited to only colorless transparent ones, and may be
colored transparent ones to which a dye or a pigment has been added.
A polyol compound such as ethylene glycol, propylene glycol or
1,1,1-trimethylol propane may also be added to the protective layer or
other layer of the present invention. Its addition can bring about a more
preferable antistatic effect.
The light-sensitive material according to the present invention may include
various light-sensitive materials including usual black and white
light-sensitive silver halide photographic materials as exemplified by
black and white light-sensitive materials for photographing, X-ray black
and white light-sensitive materials and black and white light-sensitive
materials for printing, and usual multi-layer color light-sensitive
materials as exemplified by color reversal films, color negative films and
color positive film s. In particular, the present invention is greatly
effective for high-temperature processing light-sensitive silver halide
halide photographic materials. The light-sensitive silver halide
photographic material according to the present invention will be briefly
described below.
The binder used in the photographic layers may include proteins such as
gelatin and casein, cellulose compounds such as carboxymethyl cellulose,
hydroxyethyl cellulose and dextran, sugar derivatives such as agar-agar,
sodium alginate and starch derivatives , and synthetic hydrophilic
colloids as exemplified by polyvinyl alcohol, poly-N-vinyl pyrrolidone,
polyacrylic acid copolymers, polyacrylamide, or derivatives or partially
hydrolyzed products of these, which can be used in combination. The
gelatin herein noted refers to what is called lime-treated gelatin,
acid-treated gelatin or enzymolyzed gelatin.
To the photographic component layers of the present invention, other known
surface active agents may also Be added alone or in the form of a mixture.
They are used as coating aids, and in some instances also used for other
purposes, e.g., for emulsification dispersion, sensitization and
improvement of other photographic performances.
Invention may contain in its photographic component layers the polymer
latex disclosed in U.S. Pat. No. 3,411,911.
Silver halide grains in emulsions may be those having a regular crystal
form such as a cube or an octahedron, or may be those having irregular
crystal form such as a sphere, a plate or a potato or those having a
composite form of any of these crystal forms. They may also be comprised
of a mixture of grains having various crystal forms. Tabular grains having
a grain diameter five time s or larger than grain thickness can be
preferably used in the present invention.
In the present invention, light-sensitive silver halide emulsions may be
used in the form of a mixture of two or more silver halide emulsions. The
emulsions mixed may be different in their particle size, halogen
composition, sensitivity and so forth. A substantially non-sensitive
emulsion may be mixed in a light-sensitive emulsion, or may be separately
used in a separate layer. For example, a light-sensitive emulsion
comprising spherical or potatolike grains and a light-sensitive silver
halide emulsion comprising tabular grains having a grain diameter five
times or larger than grain thickness may be used in the same layer or in
different layers. When used in different layers, the light-sensitive
silver halide emulsion comprising tabular grains may be present at the
side near to the support or on the other hand may be present at the side
distant therefrom.
EXAMPLE
Next, the present invention will be explained in detail referring to
examples. However, the present invention is not limited thereto.
(Powder P1)
By means of a spray dry method, a 10% (NP(NHC.sub.6 H.sub.5)1.6(NHC.sub.6
H.sub.4 SO.sub.3 H).sub.0.4).sub.3 solution was sprayed and dried for
collecting in a form of powder. With regard to the resulting powder, the
average particle diameter was 0.15 .mu.m, the specific gravity was 1.25
and the volume specific resistance was 2.3.times.10.sup.4 .OMEGA.cm.
(Powder P2)
By means of a spray dry method, a 10% (NP(NHC.sub.6 H.sub.5)1.6(NHC.sub.6
H.sub.4 SO.sub.3 Na).sub.0.4).sub.4 solution was sprayed and dried for
collecting in a form of powder. With regard to the resulting powder, the
average particle diameter was 0.11 .mu.m, the specific gravity was 1.35
and the volume specific resistance was 8.5.times.10.sup.4 .OMEGA.cm.
(Powder P3)
Kettin Black (produced by Agzo Corporation) was dispersed in methanol by
the use of a ball mill made of SiC so than a 10% Kettin Black dispersion
was produced. The Kettin Black dispersion of 500 cc was dropped in 100 cc
of polyacrylonitrile emulsion (concentration of 3%) while stirring at high
speed by the use of a lab mixer. After the completion of dropping,
stirring was continued for a while. The resulting mixed solution was dried
and powder was collected by means of the spray dry method. Gray powder was
obtained. With regard to the resulting powder, the average particle
diameter was 0.2 .mu.m, the specific gravity was 1.3 and the volume
specific resistance was 3.5.times.10.sup.4 .OMEGA.cm.
(Powder P4)
Kettin Black was dispersed for 2 days in methanol by the use of a ball mill
made of SiC so that a 8% Kettin Black dispersion was produced. The Kettin
Black dispersion of 500 cc was dropped in 100 cc of polyacrylonitrile
emulsion (concentration of 3%) while stirring at high speed by the use of
a lab mixer. After the completion of dropping, stirring was continued for
a while. To the solution, tin oxide sol of 5 cc produced by Tagi Chemical
Co., Ltd. was added thereto while stirring. The resulting mixed solution
was dried and powder was collected by means of the spray dry method. Gray
powder was obtained. With regard to the resulting powder, the average
particle diameter was 0.18 .mu.m, the specific gravity was 1.35 and the
volume specific resistance was 8.2.times.10.sup.4 .OMEGA.cm.
(EXAMPLE 1)
(Preparation of a support for a silver halide photographic light-sensitive
material)
To both sides of a polyethylene terephthalate film having a thickness of
100 .mu.m after biaxial stretching and thermal fixing, corona discharging
was applied at 8 W min/m.sup.2. The film thus treated was coated on one
side thereof with the following subbing coating solution B-1 as described
in Japanese Patent O.P.I. Publication No. 19941/1984, so as to form
subbing layer B-1 having a dried coating thickness of 0.8 .mu.m, followed
by drying at 100.degree. C. for 1 minute. The polyethylene terephthalate
film was further coated on the side opposite to the subbing layer B-1 side
with the following subbing coating solution B-2 as described in Japanese
Patent O.P.I. Publication No. 77439/1984, so as to form subbing layer B-2
having a dried coating thickness of 0.8 .mu.m, followed by drying at
100.degree. C. for minute.
First subbing layers
Subbing coating solution B-1
Copolymer latex solution comprised of 30% by weight of butyl acrylate, 20%
by weight of t-butyl acrylate, 25% by weight of styrene and 25% by weight
of 2-hydroxyethy acrylate.
______________________________________
(solid content: 30%) 270 g
Compound A 0.6 g
Hexamethylene-1,6-bis(ethyleneurea)
0.8 g
______________________________________
Made up to 1 liter by adding water.
Subbing coating solution B-2
Copolymer latex solution comprised of 40% by weight of butyl acrylate, 20%
by weight of styrene and 40% by weight of glycidyl acrylate
______________________________________
(solid content: 30%) 270 g
Compound A 0.6 g
Hexamethylene-1,6-bis(ethyleneurea)
0.8 g
______________________________________
Made up to 1 liter by adding water.
Second subbing layer
To the above subbing layers B-1 and B-2, corona discharging was applied at
8 W min/m.sup.2, and the following coating solution B-3 was coated thereon
so as to give a dried coating thickness of 0.1 .mu.m each, followed by
drying at 100.degree. C. for 1 minute.
Subbing coating solution B-3
______________________________________
Gelatin 10 g
Compound A 0.4 g
Compound B 0.1 g
Silica particles with an average particle diameter of
0.1 g
3 .mu.m
Powder P1 5 g
______________________________________
Made up to 1 liter by adding water.
##STR4##
(Preparation of emulsion)
In an acidic atmosphere of pH 3.0, grains containing rhodium in an amount
of 10.sup.-5 mol per mol of silver was produced by controlled double-jet
precipitation. The grains were grown in a system containing benzyladenine
in an amount of 30 mg per liter of an aqueous 1% gelatin solution. After
silver and halide were mixed, 6-methyl-4-hydroxy-1,3,3a,7-tetrazaindene
was added in an amount of 600 mg per mol of silver halide, followed by
washing to carry out desalting.
Subsequently, 6-methyl-4-hydroxy-1,3,3a,7-tetrazaindene was added in an
amount of 60 mg per mol of silver halide, and thereafter sulfur
sensitization was carried out. After the sulfur sensitization was
completed, 6-methyl-4-hydroxy-1,3,3a,7-tetrazaindene was added as a
stabilizer.
(Silver halide emulsion layer)
To the above emulsion, additives were added so as to give the following
coating weights, and the emulsion thus prepared was coated on the support
described above.
______________________________________
Latex polymer: Styrene/butyl acrylate/acrylic
1.0 g/m.sup.2
acid terpolymer
Tetraphenylphosphonium chloride
30 mg/m.sup.2
Saponin 200 mg/m.sup.2
Polyethylene glycol 100 mg/m.sup.2
Sodium dodecylbe | | |
