JPH0248181B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a deodorizing resin composition and a deodorizing packaging material, and more specifically, to the provision of a deodorizing packaging material suitable for packaging various malodorous articles. purpose.

(Prior Art) Conventionally, deodorizing agents for various sources of bad odors have been widely used, and in order to package various malodorous articles, non-porous plastic films, aluminum foils, metal Containers, glass containers, etc. are used.

(Problems to be Solved by the Invention) Packaging using conventional packaging materials with no air permeability as described above can prevent the bad odor of the contents from evaporating, but when the containers are opened, It is inconvenient to handle because the foul odor that is pervading the room evaporates outside all at once.

As a result of intensive research to solve the above-mentioned drawbacks of the prior art, the inventor of the present invention has developed a plastic film.
When producing molded products such as plastic sheets or plastic containers, when a specific substance is incorporated into the thermoplastic resin used, the resulting molded product, such as a packaging material, has excellent deodorizing properties and the above-mentioned The present invention was completed based on the finding that the drawbacks of the prior art can be solved.

(Means for Solving the Problems) That is, the present invention provides a deodorizing resin composition comprising 99.9 to 80 parts by weight of a thermoplastic resin selected from polyethylene, polypropylene, and polystyrene and 0.1 to 20 parts by weight of a deodorizing component. A deodorizing resin composition comprising a ferrous salt, citric acid and/or a citrate, and the deodorizing component is melt-kneaded in the thermoplastic resin.

Next, to explain the present invention in more detail, the present inventor has been conducting various research on deodorizing resin compositions, and by blending and using conventionally known deodorizing compounds in a specific combination, individual The present invention was completed based on the finding that a deodorizing compound exhibits a remarkable synergistic effect compared to the case where a deodorizing compound is used alone.

In the present invention, the thermoplastic resin used is
Conventionally, various molded products such as polyolefin resins such as polyethylene and polypropylene, polyvinyl chloride, vinylon, polystyrene, polyamide, polyester, and cellulose acetate, which are used for molding plastic films, plastic sheets, plastic containers, fibers, etc. These thermoplastic resins are synthetic or modified thermoplastic resins, and all of these thermoplastic resins can be easily obtained and used on the market, and these thermoplastic resins can be either solid or liquid such as paste. be.

The individual deodorizing compounds used in the present invention are all known compounds, and various ferrous salts can be used as the ferrous salt, but ferrous sulfate is particularly preferred. As the citrate, an alkali metal salt of citric acid, particularly a sodium salt, is suitable.

The main feature of the present invention is that the above-mentioned ferrous sulfate is used in combination with citric acid and/or citrate as a deodorizing component.

That is, it is known in the prior art that ferrous salts are used as deodorizing ingredients, but when such ferrous salts are kneaded into thermoplastic resins, etc., the processing temperature of the thermoplastic resins Due to the high ferrous salt content, the ferrous salt discolored and colored the thermoplastic resin brown, reducing the deodorizing effect and significantly lowering the commercial value of the resin molded product.
In the present invention, by using citric acid, citrate, or a combination of both in the ferrous salt, the ferrous salt can be used even at high processing temperatures when kneading the ferrous salt into the thermoplastic resin. , the ferrous salt does not impair its deodorizing effect, the brown discoloration of the ferrous salt is small, and together with the deodorizing effect of citric acid and/or citrate, the ferrous salt has a deodorizing effect that is greater than the sum of the unique deodorizing effects of each compound. It was discovered that it exerts a deodorizing effect.

As for the deodorizing component made of ferrous salt and citric acid and/or citrate as described above, the ratio of their usage is also important.If the total amount is 100 parts by weight, ferrous salt is 80 to The ratio of citric acid and/or citrate to 90 parts by weight is 20 to 10 parts by weight, and the most preferable combination and ratio is 80 to 90 parts by weight of ferrous salt and 15 to 5 parts by weight of citric acid. The combination and ratio of citrate is 5 to 1 part by weight, and the object of the present invention is best achieved in such a combination and ratio.

The deodorizing resin composition of the present invention has the above two components as essential components, but it also includes various conventionally known additives for resins, such as colorants, fillers, extender pigments, plasticizers, stabilizers, and ultraviolet absorbers. Agents and the like can be added as desired.

The deodorizing resin composition of the present invention can be obtained by simply mixing the above components, or may be obtained by melt-kneading the mixture and granulating it into pellets or the like. Furthermore, it may be in the form of a masterbatch containing a high concentration (for example, 10 to 20% by weight) of the deodorizing component for later use by diluting with an additive-free thermoplastic resin.

The deodorizing resin composition of the present invention as described above is useful for producing the deodorizing molded article of the present invention.

The deodorizing molded product of the present invention is a molded product of various shapes made of the above-mentioned resin composition, such as a packaging material made of plastic film or sheet, or a container of any shape made by molding the resin composition by various methods. It is a molded product.

Forming of such films, sheets, containers, etc. is carried out using conventionally known inflation devices, presses,
The molded product of the present invention can be easily obtained by using a calendar, an extrusion molding machine, a blow molding machine, an injection molding machine, a vacuum molding machine, etc., using various conventionally known conditions as they are.

(Action/Effect) It is known in the prior art that ferrous salts are used as deodorizing ingredients, but when such ferrous salts are kneaded into thermoplastic resins, Due to the high processing temperature of the ferrous salt, the ferrous salt changes color and turns the thermoplastic resin brown, reducing the deodorizing effect and significantly lowering the commercial value of the resin molded product. By using such ferrous salts with citric acid or citrate, preferably a combination of the two, the ferrous salts can be mixed into thermoplastic resins even at high processing temperatures. The ferrous salt does not impair its deodorizing effect, and the brown discoloration of the ferrous salt is small, and together with the deodorizing effect of citric acid and/or citrate, the deodorizing effect is greater than the sum of the unique deodorizing effects of each compound. It is something that demonstrates the.

Therefore, molded articles such as packaging materials made of the deodorizing resin composition of the present invention can be used for articles with strong malodors, such as
When used to package fish, fish products, various pickles, and various other foods, the packaging material itself absorbs the odor emitted by them, so even when the package is opened, strong odor will not spread to the surrounding area. . Also,
For the same reason, it is also effective for packaging not only food but also various household garbage, factory waste, etc.

In addition to the above-mentioned packaging materials, the deodorizing resin composition of the present invention can also be used in deodorizing molded products, such as granular deodorizing agents, in places where bad odors and foreign odors occur or accumulate.
It is useful as a raw material for deodorizing wall coverings, floor coverings, deodorizing fibers, textiles, and other molded products.

Next, the present invention will be explained in more detail with reference to Examples. In the text, parts or % are based on weight unless otherwise specified.

Example 1 Weight ratio of 99 parts of low density polyethylene to 10:3:1
Blend 1 part of a mixture of ferrous sulfate, citric acid and sodium citrate, mix in a mixer, and use a 40 mm extruder (L/D=28, CR=3.1, screw with dullage, cylinder temperature 130℃, screw The mixture was kneaded at a rotational speed of 70 rpm to obtain a pellet-shaped deodorizing resin composition of the present invention.

Next, the above resin composition was passed through an inflation device (30 mm extruder, 50 mm inner diameter inflation die,
Cylinder temperature 140℃, screw rotation speed 60rpm)
to obtain a polyethylene film with a wall thickness of approximately 50 microns.

Cut the above film into a size of 50mm x 210mm,
These two films were suspended in an umbrella shape inside a 300 ml Erlenmeyer flask, and the mouth was sealed with paraffin. This flask contains 42ppm as a source of bad odor.
Contains 100ml of ammonia water.
Ammonia in the flask after a certain period of time (ppm)
The results of measuring with a Kitagawa detector tube were as follows.

1 day, 2 days, 9 days later Blank 25 25 25 Inventive product 23 20 15 Comparative example 24 23 21 Note: The blank is a polyethylene film of the same thickness and size molded from polyethylene with no deodorizing component added, and the comparative example is a polyethylene film of the same thickness and size molded from polyethylene with no deodorizing component added. This is an example of using ferrous iron alone.

In addition, bags were made from each of the blank, the film of the present invention, and the film of the comparative example, and thawed small fish were placed in the bag and left to stand. When the bag was opened after 3 days, it was found that the film of the present invention The foul odor inside the prepared bag was slight, whereas in the case of the blank and comparative example, a strong foul odor was diffused. In addition, while the film of the comparative example was strongly colored brown,
The product of the present invention was hardly colored.

Examples 2 to 4 A plastic packaging material of the present invention was obtained in the same manner as in Example 1 except for using the following components, and its performance was measured in the same manner as in Example 1, and the results were as follows.

Example 2 High-density polyethylene 95 parts Ferrous sulfate, citric acid and potassium citrate 8:1.5:0.5 mixture 5 parts After 1 day After 2 days After 9 days Blank 25 25 25 Inventive product 10 7 3 Comparative example 23 20 18 Examples 3 Polypropylene 95 parts Ferrous sulfate and potassium citrate 8.5:1.5
Mixture 5 parts 1 day later 2 days later 9 days later blank 25 25 25 Invention product 10 7 4 Comparative example 23 20 18 Example 4 Polystyrene 98 parts 8.7:1.3 mixture of ferrous sulfate and citric acid
2 parts 1 day later 2 days later 9 days later Blank 25 25 25 Invention product 21 18 16 Comparative example 23 21 20 Example 5 Weight ratio of 80 parts of high density polyethylene to 10:3:1
A deodorizing resin composition of the present invention having a deodorizing component concentration of 20% was obtained in the same manner as in Example 1.

This deodorizing resin composition was diluted 20 times with additive-free high-density polyethylene, and was molded using a blow molding machine (45 mm screw, screw rotation speed 30 rpm, cylinder temperature 200°C) into a mold with a wall thickness of 1 mm and a diameter of 60 mm.
A bottle-shaped molded product with a height of 170 mm was obtained. Partially rotten meat was placed in this container and sealed, and when the container was opened after being left for 3 days, the odor was significantly weaker than in the case of the same container without any deodorizing ingredients added.

Example 6 70 parts of polypropylene and deodorizing ingredients (ferrous sulfate, citric acid and sodium citrate = 10:
Mix 30 parts of 3:1) and mix with Henschel mixer.
Mix for 2 minutes at a rotation speed of 1500 rpm, then knead with a 40 mm extruder (L/D = 28, CR = 3.1. screw with dullage, cylinder temperature 200-215°C, screw rotation speed 90 rpm) to form pellets. A deodorizing resin composition of the present invention was obtained. This was diluted 10 times with natural resin, spun at 200 to 215° C. using a spinning machine, and stretched 3 times to obtain a 15 denier fiber.

One gram of the above fibers was bundled and suspended with a thread in a 300 milliliter Erlenmeyer flask containing 10 microliters of 28% ammonia water, and the flask was sealed with paraffin to completely gasify the ammonia water. Thereafter, the change in ammonia gas concentration (ppm) over time was measured using a Kitagawa gas detection tube, and the following results were obtained.

30 minutes 120 minutes 180 minutes Blank 7500 7200 7100 Invention product 2500 1300 700

Claims (1)

[Claims] 1. A deodorizing resin composition comprising 99.9 to 80 parts by weight of a thermoplastic resin selected from polyethylene, polypropylene, and polystyrene and 0.1 to 20 parts by weight of a deodorizing component, wherein the deodorizing component is a ferrous salt, citric acid, and/or citrate. A deodorizing resin composition characterized in that the deodorizing component is melt-kneaded in the thermoplastic resin.