JPH0336543A - Reflecting photographic element improving contamination by fingerprint - Google Patents

Abstract

PURPOSE:To provide the photographic element which is resistant to the pickup of the traces of fingerprints on the image plane and has the excellent resolving power of photographic images by specifying the center line average height and the number of projections of the reflecting photographic element. CONSTITUTION:A photosensitive silver halide photographic emulsion layer is applied on at least one surface of a base consisting of a white polyester film contg. >=10wt.% titanium oxide. The center line average height on the surface of the side where the silver halide photographic emulsion layer is applied is >=0.1mum and the number of the projections of >=0.06mum height is specified to >=100 pieces per 5mm<2>. For example, the film molded from the compsn. which is added with the coarse powder of >=3mum titanium oxide obtd. by a classification treatment and/or grinding treatment of a wet process or dry process and is kneaded with polyester as a raw material is used as the base. The traces of the fingerprints are hardly picked up on the image plane and the excellent resolving power of the photographic images is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to a reflective photographic element having a support made of white polyester containing titanium oxide;
More particularly, the present invention relates to the above reflective photographic element having improved fingerprint adhesion.

[Background of the Invention] Conventionally, as a support for a reflective photographic element, a polyethylene-coated paper is generally used, which is a base paper made from pulp and a polyethylene layer formed by kneading white If diagonal or the like on top of the base paper.

However, due to the irregularities on the surface of the adjacent base paper support, the anti-rJJ photographic element using polyethylene-coated paper as a support results in a rough, ripple-like glossy surface, which reduces the brightness of the V-page image. , sharpness and the resulting beauty are markedly 1[1]. In addition, although both sides of the base paper of the support are coated with a water-impermeable thin polyethylene film, the cut surface of the base paper is not coated, so there are disadvantages such as staining due to seepage of the present fl liquid, etc. Ta.

Several methods have been proposed to overcome the above drawbacks, including using only a thermoplastic resin film as a support without using base paper.

In particular, the first British patent for technology using polyester.
, No. 563,591 and No. 1,563,592 discloses a method of adding barium sulfate to polyester and stretching it. However, this method does not provide sufficient whiteness as a support for reflective photographic elements.

This is clear from the fact that optical brighteners and other pigments are added each month in the examples of the same patent. Also, as a result of stretching,
Voids are formed around the barium sulfate particles, and when a photographic layer is coated, the resolution of the resulting image becomes insufficient. Further, Japanese Patent Publication No. 56-4901 discloses a technique in which 1iAfllf barium and butane oxide are used in combination. The patent states that the thermoplastic resins that can be used include various resins with a ul of 0 (polyester resins are also suitable, but polyester resins are not applicable due to the following two points). However, the first point is that barium sulfate and polyester have similar refractive index values, and suitable whiteness cannot be obtained unless stretched. The second point is that when titanium oxide is added to a polyester resin as it is and stretched, it creates voids around the particles, resulting in poor resolution of the image (r(1!i)). It is enough.

To improve these drawbacks, Japanese Patent Application Laid-Open No. 1986-11
No. 8746 discloses polyester having an average particle diameter of 0.1 to 0.
A non-uniform photographic element is disclosed in which an emulsion is coated on a film with the addition of 5 microns of surface-treated titanium oxide and whose film thickness and total visible light transmittance are within specified ranges. Although the above technology has improved the whiteness and resolution of anti-rJ4 photographic elements, it has the drawbacks of insufficient smoothness of the support film surface, the appearance of protruding defects, and a lack of gloss. .

[Problems to be Solved by the Invention] In order to improve the above-mentioned drawbacks, the present invention '8 etc. is disclosed in Patent No. mlil 62-333, filed on December 28, 1988.
No. 450, a reflective photographic element was disclosed in which Milk 71111 was phased on a polyester film containing titanium oxide having an average particle size within a specified range and substantially free of particles larger than 3 μm in size.

Although the above-mentioned defects and glossiness have been almost completely improved by the above-mentioned technology, fingerprint marks may be left on the image surface when printing a photograph obtained by exposing and developing a new reflective photographic element. - There was a drawback that the appearance was impaired.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned open problems and to provide a reflective photographic element which is less likely to leave fingerprint marks on the image surface and which has excellent resolution of photographic images.

[Means for Solving the Problems] In view of the above-mentioned problems, the inventors of the present invention have made extensive studies and found that the above-mentioned object of the present invention is to provide a support made of a white polyester film containing titanium oxide at 10ffi% or more. A reflective photographic element having a light-sensitive silver halide photographic emulsion layer coated on at least one surface thereof, wherein the center surface average roughness of the surface on which the silver halide photographic emulsion layer is provided is 0.1 μm or more. and the number of protrusions with a height o, oeμm or more is 5m
It has been found that this can be achieved by providing a reflection photographic a-cord characterized by more than 100 pieces per 52 pieces.

The present invention will be explained in more detail below.

In the present invention, the center surface average roughness is defined as follows.

In other words, from the roughness curved surface, the jlfi product S
When part M is extracted and the orthogonal coordinate axes, X-axis, and Y-axis are placed on the center plane of this sampled part, and the axis perpendicular to the center plane is placed as the Z-axis, the value given by the following formula is the center plane average. It is defined as roughness (SRa) and is expressed in μm.

However, LX-LY-3M Z-r(X,Y) Further, in the present invention, the number of protrusions is defined as follows.

That is, the peak detection level and the valley detection level are set parallel to the top and bottom of the center plane, separated by a hysteresis width of 0.03 μm, and the number of peaks is counted and expressed as a number converted per 5 m-2.

In the reflective photographic element of the present invention, the center surface average roughness defined as above and the number of protrusions of 0.06 μm or more per 502 are required to be 0.1 μm or more and 100 or more, respectively. but preferably each 0.2 to 2.0
The number of μm is 1200 to SOO.

The reflective photographic element of the present invention has a center surface average roughness of 0.1 μm or more on the side coated with the silver halide emulsion layer;
-■ Number of protrusions with a height of 0.06 μm or more per 2 is 100
The object of the present invention can be achieved if the particle size is 3 μm or more, and there are no particular limitations on the production method number, but preferably 3 μm or more obtained by wet or dry classification (jl+ and/or pulverization, preferably Coarse powder of titanium oxide having a particle size of 3 to 50 μm is added in an amount of 5 to 50 tons based on the total amount of titanium oxide added, and a film formed from a composition obtained by kneading with polyester is used as a support. There are several methods.

The effect of the present invention cannot be obtained with particles having a particle size smaller than 3 μm, and if particles with a particle size exceeding 50 μm are contained,
1Z1, the film may tear during stretching and stable operation may not be possible. Therefore, it is preferable to remove particles having a particle size of less than 3 μm and exceeding 50 μm by classification.

In addition, in the present invention, there is a method of adding organic or inorganic particles in addition to titanium oxide to achieve the average center surface roughness and the number of protrusions, and in this case, the average particle size is 3 to 50 μm.
It is desirable to contain at least one kind of the above-mentioned particles.

If particles with a particle size exceeding 50 μm are contained, stable operation may not be possible as in the case of titanium oxide.

Such organic or inorganic particles are preferably added in an amount of 5 to 50% based on the total amount of titanium oxide.

Typical examples of such Utsukimata tit inorganic particles include zinc oxide, barium sulfate, silica, talc, calcium chloride, and polymethyl methacrylate (PMMA).
, polystyrene, nylon, etc.

The above titanium oxide and organic or inorganic particles are added to the protective layer after coating the emulsion.

The wet classification process is a process in which titanium oxide is suspended in a liquid such as water that does not dissolve titanium oxide, and particles with a certain particle size or more are separated using the difference in sedimentation speed depending on the particle size. Depending on the method, it is classified into natural sedimentation method and centrifugal sedimentation method. Although either method can be used in the present invention, the natural sedimentation method is preferably used because of its high accuracy and simple equipment.

In addition, the suspension concentration is particularly affected by 1. There is no limit, but usually 100
It is carried out in the range of ~7001 J/Il. Further, a dispersant such as sodium hexametaphosphate can be added to the suspension.

Dry classification processing refers to a method of separating particles of a certain particle size or more by utilizing differences in behavior depending on particle size in a gas such as air.For example, I'll! Vine used by li, air heater, cyclone, etc.

In the present invention, a dry classification process is preferably used over a wet classification process in terms of accuracy of classification, ease of handling, etc.

Wet pulverization refers to the operation of pulverizing titanium oxide in a liquid such as water that does not dissolve titanium oxide, and usually
Use a pulverizer such as a ball mill, vibration mill, or sand mill. Among these, Nando mill type ones are effective, and glass beads, alumina beads, zirconia beads, Ottawa sand, etc. are used as media, and there are many commercially available models. In the case of a sand mill, the residence time in the crusher is approximately 3 to 30 minutes.

Dry pulverization is a process in which pulverization is carried out in a stream of air, nitrogen, or the like without using liquids such as water, and Henschel mixers, jet mills, and the like are used.

In the present invention (13), either the classification treatment or the pulverization treatment may be performed, or both may be performed.

In the present invention, even if the classification I18 filling Jj and/or In treatment is performed before the titanium oxide surface treatment step described below,
It may be carried out later, or it may be carried out between the mfi treatment and the organic treatment if the surface treatment involves both inorganic treatment and organic treatment.

As the titanium oxide used in the present invention, both rutile type J3 and anatase type can be used, but the anatase type is more preferably used because of its bluish color tone.

The refractive index of titanium oxide used in the present invention (n −2,5
~2.75) is the refractive index of the polyester used in the present invention (for example, the refractive index of polyethylene prephthalate is approximately 1.75).
57), so when used in the support of a reflective photographic element, it has excellent light refraction ability and the resulting photographic image has excellent conformation power.

In J3 of the present invention, titanium oxide can be subjected to surface treatment. This surface treatment is Al1. Ce.

MO, Ti, Sly, Si, Sn, Zn, Zr'F
j metal hydroxides, hydrated oxides, phosphorus M salts, or basic lii! An inorganic treatment that deposits one or more selected from acid salts, etc.]! [! 33 and/or fatty acid metal salts, various coupling agents, alcohols, amines,
This is a 71-machine treatment in which siloxane polymers, various ester compounds, phosphoric acid compounds, etc. are adsorbed onto the surface of titanium oxide and discharged.

In the present invention, the proportion of the titanium oxide contained in the polyester film is preferably 10% or more, more preferably 10 to 50%, based on the polyester from the viewpoint of whiteness, stretchability, etc. of the support film. It is preferably added in an amount of 15 to 30% by weight, and preferably added in such a manner that the total visible light transmittance of the support film is 20% or less.

In the present invention, titanium oxide may be used as one of the inorganic pigments commonly used as white pigments in the art (for example, inorganic pigments such as nitrous oxide, barium sulfate, silica, talc, calcium carbonate, etc.).
Can be used alone or in combination with two or more scales. However, the white pigment that can be used for these at is the polyester 1 of the present invention.
It should not exceed 10 parts per 00 parts by weight.

The polynisdel used in the present invention is a thermoplastic resin made only of polyester, and is a thermoplastic resin made of polyester, which is the main component, with other polymers, additives, etc. added to the extent that it does not practically change the resin properties. is also included.

The polyester used in the present invention includes aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, naphthalene dicarboxylic acid, ethylene glycol, 1.3
- Polymers of condensates with glycols such as propanediol and 1゜4-butanediol, such as polyethylene terephthalate, polyethylene 2,6-dinaphthalate, polypropylene terephthalate, polyethylene terephthalate, etc., or copolymers thereof. .

As the polyester used in the present invention, polyethylene terephthalate (hereinafter referred to as PET) is preferable. PET film does not penetrate water, has excellent smoothness, and has good mechanical properties such as tensile strength and tear strength. It has excellent dimensional stability such as heat shrinkage, and also has excellent chemical resistance during development processing.

The polyester used in the present invention is phenol/1.1,2.2-te-1-lachloroethane (60/40
The intrinsic viscosity measured at 20°C in a mixed solvent with a
It is preferably from 0.4 to 1.0, more preferably from 0.5 to 0.8.

In the present invention, when kneading titanium oxide with polyester, it is preferable that the polyester is kneaded in a molten state.

Kneading machines for cross-mixing and dispersing titanium oxide into polyester include extruders with rotors and blades for cross-mixing, twin-screw kneading extruders that rotate in the same or opposite directions, and continuous kneaders with a negative shaft. Continuous mixers and batch mixers such as three-roll mixers, Panbury mixers, Henschel mixers, and kneaders are used. Among these, a co-rotating continuous twin-screw extruder is preferably used because it allows continuous mixing while applying a repelling U-shearing force.

In the present invention, the polyester composition obtained by the above-mentioned kneading may be pelletized and then subjected to film forming, or may be subjected to film forming while in a molten state. In either method, the mnm degree may be molded as is, or a composition with a high pigment concentration, a so-called masterbatch, may be prepared and this may be diluted and molded.

For film forming, the polyester composition obtained by cross-wiring is extruded in a molten state through a slit die, grounded on a rapidly cooling surface such as a rotating drum to form an amorphous sheet, and then the amorphous sheet is heated to the glass transition temperature (To ) or more and 130°C or less, with a temperature difference of preferably 10°C or more between the front and back surfaces of the film, and stretching is carried out sequentially in a uniaxial direction in the longitudinal or transverse direction or simultaneously in both the longitudinal and transverse directions.

- The stretching ratio when stretching in the axial direction is preferably 2 to 4 times. Further, in the case of simultaneous biaxial stretching, the stretching ratio is preferably 4 to 1618 times, more preferably 6 to 12 times, in terms of area ratio. Also,
After stretching, it is preferable to carry out heat setting and heat relaxation.

The wA thickness of the film support obtained above is 50 to 30
The thickness is preferably 0 μm, more preferably 75 to 250 μm. If it is thinner than 50 μm, it will not be stiff as a support and will wrinkle easily. Further, if the field exceeds 300μ, there will be disadvantages such as the thickness becomes too thick and it becomes inconvenient to handle.

The film support of the present invention may contain various commonly used additives, such as optical brighteners, dyes, ultraviolet absorbers, antistatic agents, etc., to the extent that the purpose of the present invention is not impaired. can.

At least one light-sensitive silver halide photographic emulsion layer is coated onto the formed, opaque, whitened film support of the present invention as described above to form a reflective photographic element of the present invention. In this case, a surface activation treatment such as corona discharge and/or a subbing layer can be applied, if necessary, prior to coating the light-sensitive silver halide photographic emulsion.

As a coating method for the light-sensitive silver halide photographic emulsion layer, extrusion coating and curtain coating, which allow two or more layers to be coated simultaneously, are particularly useful. Further, the coating speed can be arbitrarily selected, but from the viewpoint of productivity, a speed of 50 m/min or more is preferable.

Here, the term "reflective photographic element" refers to a so-called transmission photographic element that projects a photographic image using transmitted light and utilizes the projected image.
It uses an opaque forest material as a support and has a photographic layer on it.[This paper is called ordinary photographic paper, in which the photographic image formed on the photographic layer is directly viewed by reflected light. Refers to photographic elements.

That is, the reflective photographic element of the present invention can be applied to any photographic element that uses the above-mentioned support, for example, it is not limited to black and white, color, etc., and even in the photographic constituent layers, light-sensitive silver halide is used. Photographic emulsion layer, intermediate layer, protection layer
, filter layer, Barafco-1~! There is no particular restriction on the number and order of layers of IJ, etc., and the invention can be applied.

As the light-sensitive silver halide photographic emulsion layer used in the present invention, various known silver halide emulsion layers can be applied.
For example, a silver halide emulsion layer consisting of silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiodobromide emulsions, etc. can be preferably used. It is also possible to include a coupler for creating a color image in the silver halide emulsion layer, and gelatin or other hydrophilic polymer substances such as polyvinyl alcohol, polyvinylpyrrolidone, etc. can be used as a binder. It is also possible to include Further, the silver halide emulsion layer contains a cyanine dye, merocyanine e.
It is also possible to sensitize the sensitive wavelength range with spectral sensitizing dyes such as A element, and chemical sensitization using various photographic additives such as anti-capri agents, gold, sulfur, etc. Agents, hardeners, antistatic agents, etc. can be preferably added.Therefore, whether the development of the reflective photographic element of the present invention is monochrome II image processing or color development processing,
The present invention is effective.

[Examples] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Anatase type titanium oxide surface-treated with alumina and polydimethylsiloxane was coated with Nissin Turbo Classifier T.
C-25M (manufactured by Nisshin Engineering 0), rotation speed 6000 rpm, % air aG, 5 m1/min, and supply amount 20
The powder was classified into coarse powder and fine powder under the conditions of ko/hour.

When the obtained coarse powder was examined, more than 90% of the powder had a particle size of 3 μm or more.

Then, 10 parts by weight of this coarse powder was mixed with 1 ota part of anatase-type titanium oxide having an average particle size of 0.37 μm.

The titanium oxide 201ffi group obtained above and the optical brightener (
Polyethylene terephthalate with 0.051ffi part and intrinsic viscosity @ 0.80
0 overlapping section and co-rotating three-wheel screw kneading extruder (
Melt with A-Tomabzuku Z CM 53/60) and!
After 1 kneading, it was made into belent.

This pellet was air-dried at 180°C for 6 hours, then melted in an extruder and extruded from a slit die onto a rapidly cooling rotary drum to form an amorphous sheet with a film thickness of 1.4mm, and then longitudinally rotated at 95°C. 2.6 (9 stretches, then 1 in the horizontal direction)
Stretched 3.0 times at 10°C, then heat-set at 210°C,
Then 0.5% in the horizontal direction! Ifll! After cooling, a white opaque film support having a thickness of 180 μm was obtained.

The total visible light transmittance of this film was 5.0%.

After coating this film with a subbing layer consisting of a terpolymer of styrene-butadiene-maleic anhydride, corona discharge was applied, and on top of this a gelatin-silver halide photographic emulsion, which is commonly used in color photographic paper, was applied. Dry! Thickness is 15μm
Reflection photographic element sample No. 091 was prepared.

Regarding the obtained sample N001, the center surface average roughness was 5 m
The number of protrusions with a height of 0.06μ or more per m2, resolution, and fingerprint adhesion were measured and evaluated as follows, and the results are shown in Table 1.
Shown in

(Evaluation method) Center surface average roughness and number of protrusions with a height of 0.06μ or more per 5-12... Using a three-dimensional surface roughness measuring machine (SE-30) manufactured by Koita Research Institute , a cutoff value of 0.25 mm with a diamond nail of diameter 4 um.

Horizontal magnification magnification 2018, height magnification magnification 20
It was determined by measuring an area of 5 mm2 at 00x magnification. Further, the feeding speed on the measurement side at this time was about 0.5+em/sec.

Resolution: A heavy line chart for measuring resolution is printed onto the reflective photographic element sample. After exposure, development is performed in the usual manner.
The optical mrx difference of the heavy line purine 1 image was measured using a microdensitometer PDM-5 (manufactured by Konica i), and the value expressed by the following formula was defined as the resolution.

5/111 smuggled print images (%) 0.1 7ym (DW!, density difference between DIla× and [)sin of flal liplin image Fingerprint adhesion...Put your finger on the reflective photographic element sample [The fingerprint traces on the image surface were visually evaluated according to the following criteria.

O: Fingerprints are hardly visible.

0: Fingerprints can be observed very slightly.

Δ...Fingerprints are slightly visible.

×: Fingerprints can be clearly seen.

If the level is 0 or higher, there will be no practical problem and the reflective photographic element will have excellent fingerprint adhesion.

At a level below Δ, the appearance will be impaired and the fingerprint adhesion will be compromised.

Comparative Example 1 Anatase type titanium oxide 20 with an average particle size of 0.37μ layer
1 part and optical brightener (Sandoz Co., Ltd. Sukopur EGM)
Polyethylene terephthalate 1-80ff with 0.05 parts by weight and intrinsic viscosity O, aO! ffi part were melt-kneaded in the same manner as in Example 1, and then formed into pellets. Using this pellet, a white opaque film support having a thickness of 180 μm was obtained in the same manner as in Example 1.

Next, a silver halide photographic emulsion was coated on the obtained film support in the same manner as in Example 1 to obtain a defective photographic element sample No.
02 was prepared, and the three-dimensional roughness, resolution, and fingerprint adhesion of this sample were measured and evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 2 The amount of coarse powder added in Example 1 was changed to 0.5 kg, and the average particle size was 0.
．． The addition m of anatase type titanium oxide of 37 μm was 19.
Sample N was prepared in the same manner as in Example 1 except that the 511m section was replaced with
0.3 was prepared, and the three-dimensional roughness, resolution, and fingerprint adhesion of this sample were evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Example 2 The amount of coarse powder added in Example 1 was 5ififf and 1 part, and the mother of anatase type titanium oxide with an average particle size of 0.37μ was added to 15f.
Sample N was prepared in the same manner as in Example 1 except that 1 part of flff was used.
0.4 was prepared, and the three-dimensional roughness, resolution, and fingerprint quality of this sample were evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 3 Addition m of coarse powder in Example 1 was 1 part by weight, average particle size 0.3
Sample N005 was prepared in the same manner as in Example 1, except that 1 μm of anatase-type titanium oxide fleas was replaced with 19 parts by weight.
Example 1
Table 1 shows the results of the same evaluation.

Table 1 From the results in Table 1, it can be seen that samples Nos. 1, 4, and 5 of the present invention are all excellent in resolution and fingerprint adhesion.

Furthermore, contrary to the expectation that the sample of the present invention would lack gloss and feel of luxury, the lack of surface waviness resulted in a print that had a smoother, calmer, and more luxurious feel than the conventional paper support.

[Effect of the Invention J As described above in detail, the present invention makes it possible to provide an anti-fouling photographic element with excellent fingerprint adhesion and excellent resolution of photographic images.

Claims (1)

[Claims] A reflective photographic element having a light-sensitive silver halide photographic emulsion layer coated on at least one side of a support made of a white polyester film containing 10% by weight or more of titanium oxide, wherein the silver halide photographic emulsion layer is coated with the light-sensitive silver halide photographic emulsion layer. The center surface average roughness of the surface on which the surface is provided is 0.1 μm or more, and the height is 0.1 μm or more.
A reflective photographic element characterized in that the number of protrusions with a diameter of 0.6 μm or more is 100 or more per 5 mm^2.