JPS6216356A - Functional synthetic resin film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel functional synthetic resin film that is transparent and has ultraviolet shielding ability and deodorizing ability.

Synthetic resin films are widely used in various fields such as packaging materials, various tapes, agricultural and gardening materials, stationery, WWI, and miscellaneous goods. Among them, it is consumed in large quantities as a packaging material, and is used in the packaging of a wide variety of products such as foods, medicines, appliances, clothing, and daily miscellaneous goods, but it is especially indispensable to the field of food packaging.

Foods are susceptible to deterioration in quality, although the degree of deterioration varies depending on the processing method and product, and an important point in packaging is how to prevent this. Deterioration includes rotting, rancidity, and the effects of ultraviolet light, making it extremely difficult to protect against ultraviolet light when using transparent packaging.

Common countermeasures include using opaque materials such as aluminum foil that do not allow light to pass through, applying opaque printing to block light, or preventing films containing organic ultraviolet absorbers from coming into direct contact with food. In addition to placing the food in the middle layer of a laminate of several layers of transparent film, there are other methods such as using a resin that does not allow UV rays to pass through, but these methods have problems such as making it impossible to see the contents of the food and being expensive. For this reason, it is not widely used except in special products, and many foods are still not protected from ultraviolet rays. However, in recent years, transparent packaging materials that allow the contents to be seen are increasingly being used for frozen foods, paste products, etc., and as they are exposed to more and more fluorescent lights in show windows, they are highly safe and transparent. There is a strong need for packaging materials that have UV-shielding properties that are both durable and economical.

On the other hand, many foods generally have strong odors, and even if foods with strong odors, such as fresh foods and pickles, are packaged in the commonly used polyethylene or polypropylene films, the odor leaks outside and is very serious. Not only is it unpleasant, but it also causes problems such as giving off odor to other items. One possible solution to this problem is to use a synthetic resin film with low gas permeability, but there are drawbacks in terms of cost and processability, and no effective solution has been found. At present, we are trying to resolve the issue.

The present inventors thought that a synthetic resin film containing both an ultraviolet shielding agent and a deodorizing agent would be effective in solving this situation, and developed a transparent synthetic resin film that has the dual functions of ultraviolet shielding and deodorizing. It was invented.

The synthetic resin film of the present invention is produced by adding and mixing a synthetic resin masterbatch containing an ultraviolet shielding agent and a deodorant in a required amount to a synthetic resin that is a raw material for the film, which has been prepared in advance to a required concentration.
It can be obtained by a commonly used molding method.

Depending on the forming method, it is also possible to form a film without forming a masterbatch.

The ultraviolet screening agent referred to in the present invention may be one that blocks ultraviolet rays by reflecting or scattering them, or one that absorbs them; for example, oxides such as Ti, Fe, Zn, AI, Si, etc., carbonates such as Ca + Mg + BB, etc. In addition to inorganic UV absorbers such as and sulfates, organic UV absorbers such as salicylic acid derivatives, benzophenone derivatives, benzotriazole derivatives, and cyanoacrylate derivatives are included.

Among these, inorganic ones are not compatible with the resin, so depending on the amount added, the transparency tends to decrease. Therefore, in order to obtain favorable results, it is desirable that the particle size is minute, and the average particle size is 0.5 mm, which is shorter than the wavelength of visible light.
When it is 1 μm or less, transparency can be maintained sufficiently within a practical addition amount range. Although organic ultraviolet absorbers are most advantageous in terms of transparency, there are some concerns about their safety to the human body. Therefore, highly safe inorganic oxides with small particle sizes are suitable for implementing the present invention. There is. In particular, ultrafine particles of titanium oxide, iron oxide, silicon oxide, and calcium carbonate, which have been developed in recent years and have an average particle diameter of 0.1μ or less, have excellent ultraviolet shielding ability, transparency, and safety, and are suitable for use in the present invention. Perfect for implementation. The amount of these ultraviolet screening agents added to the synthetic resin varies depending on the thickness of the film and the degree of shielding, but a practical amount of 5% or less is sufficient.

The deodorizing agent as used in the present invention is a synonym of the deodorant, and the deodorizing mechanism may be based on a chemical reaction, physical adsorption, or other mechanism, and is not particularly limited.

For example, there are substances extracted from natural products that have an unclear chemical structure but have a deodorizing function, iron compounds stabilized with ascorbic acid, acid-base substances, porous aluminosilicate, and other substances that usually have a deodorizing function. It's good to have. Among these, in particular, the deodorizing preparation (trade name: Fresh Shiraimat) containing an isolate from a plant of the Camellia family as an active ingredient, described in JP-A-58-61751, is extremely effective against basic odors, which are the causative agents of fishy odor. It is effective, transparent, and safe, making it optimal. The amount of the deodorant added to the synthetic resin is determined by taking into consideration the type of odor to be deodorized, the type of deodorant, etc., and is not particularly limited.

The term "transparent" as used herein refers to a film that allows the appearance of an article in contact with the film to be confirmed, and includes what is normally described as translucent.

The synthetic resin used in the present invention may be any material that can be formed into a film, such as high or low density polyethylene, lippyrolene, polyvinyl chloride, polyvinylidene chloride, polyamide,
Examples include polyester, EVA and its hydrolyzate, polyvinyl alcohol, and the like.

Next, the present invention will be explained with reference to examples, but the present invention is not limited to these examples.

Example 8 parts of ultrafine titanium oxide having an average particle size of 0.015 μm and 2 parts of a deodorizing preparation separated from a plant of the Camellia family were kneaded into 90 parts of low-density polyethylene to prepare a masterbatch. Five parts of this masterbatch was added to and mixed with 95 parts of low density polyethylene, and a film of Example 1 was obtained by an inflation method. Films of Examples 2 and 3 were obtained in substantially the same manner.

The film of Example 4 was then prepared as follows. 100 parts of polyvinyl chloride resin, 40 parts of dioctyl phthalate, 2 parts of organotin stabilizer, 0.3 part of ultrafine titanium oxide with an average particle size of 0.05μ, and 0.1 part of the same deodorant as in Examples 1 to 3.
The mixture was mixed with a blender, kneaded with a mixing roll, and formed into a film by calendering. Table 1 shows examples of the films of the present invention.

Table 2 shows the ultraviolet shielding ability and ammonia deodorizing ability of the film in terms of removal rate.

(The following is a blank space) As shown in Table 2, the film of the present invention has a low transmittance and a large shielding effect in the ultraviolet region, and conversely has excellent transparency in the visible light region. It is also highly effective in deodorizing, making it ideal for various packaging materials.

Claims (3)

[Claims] (1) A transparent functional synthetic resin film containing an ultraviolet shielding agent and a deodorant. (2) Titanium oxide, iron oxide, zinc oxide, silicon oxide, calcium carbonate, magnesium carbonate,
The synthetic resin film according to claim 1, which contains one or more organic ultraviolet absorbers. (3) Contains one or more of titanium oxide, iron oxide, silicon oxide, and calcium carbonate with an average particle size of 0.1μ or less as an ultraviolet shielding agent, and uses an isolate from a plant of the Camellia family as an active ingredient as a deodorizer. Claim 1 containing a deodorant preparation
Synthetic resin film.