JPH04306647A - White polymer compound, reflection supporting body for photograph using it, and supporting body for photographic paper - Google Patents

Abstract

PURPOSE:To obtain a reflection supporting body for photograph which processes the superior uniformity of white polymer compounds having high light scattering performance and the light reflection efficiency and a supporting body for photographic paper which has the superior glossiness and high quality. CONSTITUTION:A polymer compound is formed by allowing a polymer to contain the hollow polymer particles having an average particle diameter of 0.1-1.0mum, and a reflection supporting body for photograph is formed by shaping the polymer compound to a film form, and a supporting body for photographic paper is formed by covering a base paper, at least the surface on the emulsion coating side with a thin film of he compound.

Description

[Detailed description of the invention]

0001

[Industrial Applicability] The present invention relates to a light-scattering polymer composition, and in particular to a white polymer composition with excellent gloss and film uniformity, and a reflective support for photography and photographic paper using the same. Regarding the support.

0002

BACKGROUND OF THE INVENTION Conventionally, polymer compositions containing kneaded and dispersed titanium oxide have been used in photographic reflective supports or photographic paper in order to increase light reflection efficiency.
For example, JP-A-2-235045 and JP-A-2-242846). When kneading and dispersing titanium oxide into the above polymer, the kneading is usually done in a closed system at high temperatures to prevent deterioration due to oxidation of the polymer, so oxygen in the titanium oxide is lost and Ti2+ becomes Ti3+. However, there was a drawback that the whiteness of titanium oxide decreased (Japanese Patent Application Laid-open No.
242846).

[0003] If the amount of titanium oxide added is increased in order to obtain sufficient whiteness, the resulting polymer composition, when used as a film, has the drawbacks of lowering the glossiness and deteriorating the uniformity of the film. will occur.

[0004] As a result of intensive studies to solve the above-mentioned drawbacks, the present inventors found that by using hollow polymer fine particles with high affinity for polymers instead of titanium oxide, not only light reflection efficiency but also gloss and film quality could be improved. It was discovered that very good results in uniformity could be obtained,
We have arrived at the present invention.

[0005]

SUMMARY OF THE INVENTION Accordingly, a first object of the present invention is to provide a polymer composition that has excellent light reflection efficiency and uniformity. A second object of the present invention is to provide a photographic reflective support that has excellent uniformity and light reflection efficiency. A third object of the present invention is to provide a support for photographic paper that is excellent in uniformity, light reflection efficiency, and gloss.

[0006]

[Means for Solving the Problems] The above-mentioned objects of the present invention are to provide a polymer composition containing hollow polymer particles having an average particle size of 0.1 to 1.0 μm in a polymer, and a polymer composition prepared using the same. This was achieved by a reflective support for photography and a support for photographic paper.

The hollow polymer particles used in the present invention are:
They are white particles of polymer that reflect light because the interior is not filled with polymer and is hollow. Unless the hollow polymer described above dissolves during kneading with the polymer containing it (hereinafter referred to as the main polymer) at high temperatures and becomes unable to maintain its hollow state,
The material is not particularly limited, but it is preferably made of a crosslinked polymer, and in particular, one with a high degree of crosslinking is preferred. Examples of such highly crosslinked hollow polymers include hollow polymers of styrene-acrylic resin manufactured by Nippon Gosei Rubber Co., Ltd.

The average particle size of the hollow polymer used in the present invention is preferably 0.1 to 1.0 μm. 0.1μ
If it is less than 1.0 μm, it will be difficult to uniformly disperse it in the polymer, and if it exceeds 1.0 μm, it will be difficult to smooth the surface roughness when made into a film, making it impossible to obtain high gloss. .

[0009] Also, the inner pore diameter of the hollow polymer is 0.05~
The thickness is preferably 0.7 μm. Inner hole diameter is 0.05μ
When it is less than m, light scattering is insufficient and high whiteness cannot be obtained. On the other hand, when the inner pore diameter is 0.7 μm or more, it is not preferable because it becomes difficult to maintain the hollow state during kneading or extrusion molding under high temperature and high pressure conditions.

In the present invention, the material of the main polymer in which the hollow polymer is dispersed is not particularly limited, but when the composition of the present invention is applied to a photographic reflective support, polyethylene terephthalate is a typical material. It is particularly preferable to use polyesters such as these and cellulose derivatives typified by cellulose triacetate. When applied as a film to cover the surface of a base paper of photographic paper, it is preferable to use polyolefins such as polyethylene and polypropylene.

[0011] Also, unlike inorganic substances, hollow polymers have good affinity with the main polymer, so they can be contained in the main polymer in larger amounts than conventional white inorganic pigments, but usually their content is 0. It is preferable to set it as .1-20 weight%. If the content is 0.1% by weight or less,
When made into a film, the whiteness is insufficient and the intended hiding effect for the base material etc. in photographic applications is insufficient, but when the content is 20% by weight or more, the unique physical properties of the main polymer are maintained. It becomes difficult to do so.

As is known, the hollow polymer and the main polymer are kneaded at the melting temperature of the main polymer and under conditions where they do not come into contact with oxygen so as to prevent oxidative deterioration due to oxygen. Conditions that do not come into contact with oxygen are usually achieved by using a closed type, but are not limited thereto. In this case, since the whiteness due to the hollow polymer does not change before and after kneading, the desired whiteness can be easily achieved by using a designed mixing ratio.

The polymer composition obtained as described above can be suitably made into a film by a known method.
You can also use it as it is as a reflective support for photography.
It can also be used as a support for photographic paper by thinly coating the surface of base paper.

[0014]

Effects of the Invention As detailed above, the polymer composition of the present invention is composed of a mixture of a hollow polymer and a main polymer that have good affinity, so even if the amount of the hollow polymer added is increased, the composition remains uniform. The properties are good. Therefore, the whiteness of the film obtained from the composition of the present invention is sufficient;
In addition to being able to be used as a reflective support for photography, when a support for photographic paper is manufactured, the support for photographic paper has excellent not only whiteness but also gloss.

[0015]

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited thereto.

Example 1. Polyethylene terephthalate (PET) with a polymerization degree of 100
100 parts, the average particle size is 0.7 μm, and the average inner pore size is 0.7 μm.
5% by weight of 4 μm styrene-acrylic resin particles (highly crosslinked polymer particles manufactured by Japan Synthetic Rubber Co., Ltd.) were added under sealed conditions.
After kneading at 295° C., the mixture was extruded into a film and cooled to produce a 30 μm thick PET film. The resulting film was evaluated for gloss, surface roughness, hiding effect, and hardness according to the following methods, and all evaluations were good.

Comparative Example 1. Instead of 5% by weight of the styrene-acrylic resin used in Example 1, 10% by weight of titanium oxide with an average particle size of 0.5 μm was added.
A film was produced in exactly the same manner as in Example 1 except that the film was used, and the obtained film was evaluated, and the same evaluations as in Example 1 were obtained regarding surface roughness, hiding effect, and hardness. However, the gloss was inferior.

Comparative Example 2. Instead of the styrene-acrylic resin particles with an average particle diameter of 0.7 μm and an average inner pore diameter of 0.4 μm used in Example 1, particles with an average particle diameter of 0.08 μm and an inner pore diameter of 0.05 μm were used. The rest was the same as in Example 1, and the surface roughness and hardness were as good as in Example 1, but the gloss and hiding effect were inferior.

Comparative Example 3. Example 1 except that instead of the styrene-acrylic resin particles with an average particle diameter of 0.7 μm and an average inner pore diameter of 0.4 μm used in Example 1, particles with an average particle diameter of 1.2 μm were used.
When the same method as above was used, the hardness was good, but the gloss, surface roughness, and hiding effect were poor.

Comparative Example 4. The same procedure as in Example 1 was used, except that instead of the styrene/acrylic resin particles with an average particle diameter of 0.7 μm and an average inner pore diameter of 0.4 μm used in Example 1, particles with an average particle diameter of 0.04 μm were used. When the same procedure was carried out, good results were obtained in terms of gloss, surface roughness, and hardness similar to those in Example 1, but the hiding effect was insufficient.

Comparative Example 5. Instead of the styrene/acrylic resin particles with an average particle size of 0.7 μm and an average inner pore diameter of 0.4 μm used in Example 1, particles with an average particle size of 0.9 μm and an average inner pore diameter of 0.8 μm were used. Except for the above, the same procedure as in Example 1 was carried out, and although evaluations equivalent to those of Example 1 were obtained in terms of gloss, surface roughness, and hardness, the hiding effect was inferior.

Comparative Example 6. The amount of styrene/acrylic resin used in Example 1 was reduced to 0.
．． When the same procedure as in Example 1 was carried out except that the amount was 2% by weight, the gloss, surface roughness and hardness were good, but the hiding effect was insufficient.

Comparative Example 7. The amount of styrene/acrylic resin used in Example 1 was 25
When the same procedure as in Example 1 was carried out except for the weight percentage, the gloss and hiding effect were sufficient, but the surface roughness and hardness were inferior. The above results are summarized in Table 1.

[Table 1]

Claims (3)

[Claims] Claim 1: In the polymer, the average particle size is 0.1 to 1.
．． A polymer composition containing hollow polymer particles of 0 μm. 2. A photographic reflective support comprising a polymer film containing hollow polymer particles having an average particle size of 0.1 to 1.0 μm. [Claim 3] At least on the emulsion-coated surface of the base paper,
A support for photographic paper coated with the polymer composition according to claim 1.