JP3449896B2 - Thermoplastic resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to foods, medical supplies,
The present invention relates to a thermoplastic resin composition suitable as a packaging or storage material for industrial parts and the like, and a material for industrial materials. Since this material has excellent permeability to carbon dioxide and oxygen gas, it retains the freshness of foods, produces little odor, retains the taste of contents such as foods, and is used in the packaging of medical supplies. It is excellent in suppressing the offensive odor generated during ionizing radiation sterilization.

[0002]

2. Description of the Related Art Heretofore, thermoplastic resins have been widely used in fields such as packaging or storage materials for foods, medical supplies, industrial parts, materials for industrial materials, etc., by making use of their respective characteristics. Among them, polyolefin resins are generally inexpensive, lightweight, transparent, mechanical strength, heat resistance,
It has excellent chemical resistance and oil resistance and is widely used in various fields. In recent years, as these functions have been improved or costs have been reduced, it has been demanded to improve the characteristics of materials. For example, polyolefin resins are hydrophobic resins and are used in various packaging fields from the viewpoint of easy heat sealability and moldability. Food packaging materials and medical packaging materials are exposed to ionizing radiation such as electron beams and γ-rays of cobalt 60 for the purpose of sterilizing the contents of packaging, but polyolefin resins are severely deteriorated by auto-oxidation when they are exposed to ionizing radiation. There is a problem that an offensive odor is generated. For example, in ordinary polyethylene, acids such as carboxylic acids, ketones, alcohols, etc. are generated by γ-ray irradiation, and even in cross-linked polyethylene, both decomposition and cross-linking reactions occur in a low dose range of 5 Mrad or less, which gives off an offensive odor. It is the cause.

As a method of preventing such irradiation odor, a method of blending an inorganic hydroxide such as calcium hydroxide with a polyolefin resin is disclosed in JP-A-60-181147. Further, a method of enclosing a gas adsorbent in a packaging bag as disclosed in JP-A-60-176659 is disclosed. However, all of these methods have a problem that the control of irradiation odor is not sufficient, the gas adsorbent is expensive, the handling is complicated, and the like, so that it is not practically applicable industrially or commercially. In addition, the taste of the contents may be altered by subjecting it to heat sterilization such as retort sterilization treatment such as retort foods, or the odor of the polyolefin resin used, a so-called poly odor is generated, and the taste of the contents, There was a problem that the flavor changed. Therefore, an HTST sterilization method in which heat sterilization is performed at a temperature of 130 ° C. or higher in a short time has been developed, and a packaging body adapted thereto has been proposed (for example, Japanese Patent Publication No. 55-24420). However, even with such an HTST sterilization method, the deterioration of the taste and flavor of the contents was still insufficient.

On the other hand, polyolefin resins have been used in the field of food freshness-keeping packaging because of their low cost, easy heat-sealing property and high gas permeability. In general, vegetables, root vegetables, fruits, flowers, flowers, mushrooms (hereinafter abbreviated as “fruits and vegetables”) are transferred from conventional open-field cultivation to systematic multi-cultivation by cultivation in horticultural facilities, producing, packing and transporting large quantities of vegetables and fruits. The means to do is adopted. The problem of such fruits and vegetables in the distribution process before reaching the consumer is how to maintain the freshness of the fruits and vegetables when they are harvested. In general, fruits and vegetables continue the ripening process even after harvesting, causing changes such as aroma and color change of fruits and vegetables and softening of pulp. Depending on the type of fruits and vegetables, depending on their type, if they have grown to a certain stage, they do not wait for ripening, and even if they are harvested when they are immature, they are ripened after harvest and become edible. Some can be used as food. This phenomenon of maturity of fruits and vegetables after harvest is called ripening, and this phenomenon is used to transport and store fruits and vegetables, and in general, the ripening action is blocked as necessary, or conversely promoted. I am doing it.

As a conventional technique for inhibiting the ripening action of fruits and vegetables to extend the transportation and storage period, there is known a method of adsorbing ethylene which causes a phenomenon of an increase in respiratory action accompanying ripening of fruits and vegetables (for example, JP-A-56-887
52, JP-A-63-110186, JP-A-63-277249, etc.). In addition, a method in which a hole is formed in a film and used (for example, Japanese Patent Publication No. 8-11036, Japanese Patent Publication No. 8-11037, and JP-A-62-235)
No. 086, Japanese Patent Laid-Open No. 4-327160, etc.) have been disclosed. Furthermore, as a method of preventing decay due to the growth of microorganisms after harvest (for example, mold),
Wash fruits and vegetables with salt water or chlorine water, mix alcohol preparations, antibacterial substances into synthetic resin film or non-woven fabric, or put the coated product together with fruits and vegetables in a cardboard box or synthetic resin film package. A method of storing or directly spraying the antibacterial agent in the form of mist has been proposed.
However, these conventional techniques have not been sufficiently effective in terms of keeping freshness.

Further, there has been a troublesome work such as providing a washing step after harvesting and putting fruits and vegetables into a cardboard box or a synthetic resin package together with alcohol. In the surface coating method, the loss of the antibacterial substance was large and it was difficult to control the freshness retention. The method of opening holes in the film is not only insufficient in freshness-retaining effect, but also inferior in impact resistance when the weight of fruits and vegetables is large, when packaging pointed fruits and vegetables and during the distribution stage. There was a problem that it was easy to break the bag. Further, as a freshness-keeping technique using hinokitiol, a synthetic resin film containing hinokitiol (for example, JP-A-3-167261 and JP-A-4-16761).
325069, JP-A-4-359028,
JP-A-4-359029, etc.), which is mixed with a printing ink and printed on a synthetic resin film (for example, JP-A-6-359029).
-16990 publication). However, since this hinokitiol is a sublimable substance, it is difficult to handle.

The tuff sandstone in the mineral used in the present invention is a kind of natural sedimentary rock, and as a prior art using the natural sedimentary rock, a bath device using substantially spherical ceramic balls (Japanese Patent Laid-Open No. 2-224759). Gazette), plant nutrients and air purifiers containing fine powder of feldspar sandstone or feldspar wacke as a main component, dehumidifying agents (JP-A-8-59402 and JP-A-8-57304), and specific component amounts. Health promoting agent and cerebral metabolism promoting / cerebral function improving therapeutic agent mainly composed of natural sedimentary rocks belonging to feldspar and feldspar wakke (Japanese Patent Laid-Open No. 8-59488 and 8-59)
No. 487) and the like are disclosed. However, in any of these, by blending a mineral containing tuff sandstone as a main component in a thermoplastic resin as in the present invention, the freshness of food is maintained, the occurrence of offensive odors in medical products is suppressed, and in the case of retort foods, etc. Nothing is disclosed about retaining the taste of the contents during retort sterilization.

[0008]

The object of the present invention is to enhance the gas permeability of a thermoplastic resin material, to improve the freshness retention of fruits and vegetables, and to sterilize it by ionizing radiation when used in medical packaging. It is an object of the present invention to provide a thermoplastic resin composition that suppresses the generation of offensive odors during storage and that retains the taste of the contents during retort sterilization of retort foods.

[0009]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that blending a specific fine powder with a thermoplastic resin is effective for achieving the object. That is, the present invention relates to (A) thermoplastic resin,
(B) A thermoplastic resin composition containing fine powder of minerals containing tuff sandstone as a main component. The blending amount is preferably 0.01 to 10% by weight.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below. The thermoplastic resin as the component (A) used in the present invention is
Polyolefin, polyvinyl chloride, polyvinylidene chloride, ethylene vinyl acetate copolymer saponified resin, polyamide, polyester, polystyrene, polycarbonate,
Examples thereof include polymethylpentene, ethylene-alkyl ester-maleic anhydride terpolymer, ethylene-alkyl ester-glycidyl terpolymer, and the like. These may use 1 type or a mixture of 2 or more types. Among these, polyolefin resins are particularly preferable.

Polyolefin resins include ethylene, propylene, 1-butene, 1-hexene and 3-methyl-1-.
A homopolymer of an α-olefin having 12 or less carbon atoms such as pentene, a random or block copolymer of these α-olefins, or an α-olefin as a main component, and vinyl acetate, acrylic acid, methacrylic acid, acrylic Examples thereof include copolymers with acid alkyl esters, methacrylic acid alkyl esters and the like. Specifically, high density polyethylene, low density polyethylene, linear low density polyethylene, polypropylene, ethylene-propylene random copolymer, ethylene-propylene elastomer, ethylene-1-butene elastomer, ethylene-propylene-1-butene random. Copolymer, ethylene-propylene block copolymer, ethylene-propylene-1-butene block copolymer, ethylene-vinyl acetate copolymer,
Propylene-1-butene random copolymer, ethylene-
Examples thereof include acrylic acid copolymers, ethylene-methacrylic acid copolymers, and ionomer resins which are metal salts thereof.

[0012] (B) a kind of tuffaceous sandstone natural sedimentary rocks in the component, which was generated in the neutral Daishiro Aki, are those often seen in the formation of western Japan, Niwa, Kawataira, Matsumoto (Ken ), Matsumoto (Hiroshi); Journal of the Japanese Society of Inflammation, Volume 16, No. 6, pp425-436 (1996), and the like, are introduced as far-infrared radiators. As for natural sedimentary rocks, the green tuff (green tuff, for example, Otaniishi), which is stratigraphically newer than the tuff sandstones produced in western Japan and is mainly produced in eastern Japan, is famous. However, it is distinguished from the tuff sandstone used in the present invention. This green tough has a larger specific surface area and pore volume than the mineral mainly composed of tuff sandstone used in the present invention. Tuff sandstone is a type of volcaniclastic rock mainly composed of volcanic ash, which is a fragment of volcanic debris.Generally, structural minerals show fractured structure and include high-temperature quartz, plagioclase, alkali feldspar, microcline feldspar, etc. It contains a small amount of colored minerals such as volatile stones and shiso stones. The present invention is a blend of a thermoplastic resin and a mineral containing tuff sandstone as a main component. That is, this mineral mainly includes tuff sandstone and tuff sandstone, and also includes a mixture of clay, which has quartz, feldspar, chlorite, amphibolite and mica as a structural mineral. The mineral mainly composed of tuff sandstone used in the present invention is S
iO ₂ 60 to 75% by weight, Al ₂ O ₃ 6 to 21% by weight,
MgO 0.5-4 wt%, CaO 1-4 wt%, F
e ₂ O ₃ 1 to 4% by weight, Na ₂ O 0.8 to 6% by weight,
It contains 0.5 to 4% by weight of K ₂ O. In particular, Si
O ₂ 63 to 73 wt%, Al ₂ O ₃ 8~21 wt%, M
gO 0.6 to 3.5% by weight, CaO 1 to 3.5% by weight, Fe ₂ O _{3 1 to} 3.5% by weight, Na ₂ O 1 to 5% by weight, K ₂ O 1 to 3% by weight Those are preferable.

The mineral components containing tuff sandstone as the main component are in the above-mentioned range, and among them, the dehydration function improving effect,
In order to enhance the effect of maintaining the taste and flavor of foods, those having the following component ranges are preferable (% is based on weight, the same applies hereinafter). Fe ₂ O ₃ and MgO total amount 2 to 7% Na ₂ O and K ₂ O total amount 4 to 8% K ₂ O / Na ₂ O (weight ratio) 0.3 to 2.5 Na ₂ O and K ₂ Total amount of O, MgO, and CaO 5 to 15% MgO / CaO (weight ratio) 0.4 to 3.0 Further, Ni, Rb, Sb, Cs, Pb, Bi, Y, L
It is preferable to include a compound of a, Ba, Zn, and Cu in the range of 0.05 to 0.40% in total as these elemental components. More preferably, it is in the range of 0.1 to 0.35%.

The mineral containing tuff sandstone as the main component (B) has an average particle size of 0.1 to 20 μm and a specific surface area of 50 m.
It is preferably ² / g or less and the pore volume is 1.0 cm ³ / g or less. This is because the minerals mainly composed of tuff sandstone generally contain volatile components, and thus secondary aggregation easily occurs, and if the average particle size exceeds 20 μm, dispersion failure easily occurs. Not only the appearance of the molded product is impaired due to the occurrence of many fish eyes and fish eyes,
There is a problem that the printability is deteriorated due to gel and fish eye. On the other hand, if it is less than 0.1 μm,
It is not preferable because it has a problem of ease of handling during mixing and a problem of water resistance and chemical resistance. Preferably 0.5 to 1
The range is preferably 5 μm, particularly preferably 0.8 to 10 μm.
The range is good.

The specific surface area is preferably 50 m ² / g or less. When the specific surface area exceeds 50 m ² / g, the freshness-retaining property, the effect of suppressing the offensive odor and the maintenance of taste and flavor are poor, which is not preferable. It is preferably 40 m ² / g or less, particularly preferably 30 m ² / g or less. On the other hand, the lower limit of the specific surface area is not particularly limited, but is generally 3 m ² / g.
The pore volume is preferably 1.0 cm ³ / g or less in terms of the freshness-retaining effect, the effect of suppressing off-flavor, and the maintenance of taste and flavor. It is preferably 0.8 cm ³ / g or less, particularly preferably 0.5
It is preferably cm ³ / g or less.

The mineral mainly composed of tuff sandstone corresponding to the component (B) of the present invention is preferably produced in the Kyushu-grandmother-inclined mountain area, Osuzuyama area, Osumi Peninsula and Yakushima. Commercially available from Only Chemical Co., Ltd.
E: Super Grouth Energy ", and these can be preferably used. The blending amount of the thermoplastic resin composition of the present invention is in the range of 0.01 to 10% of (B) a fine powder of minerals containing tuff sandstone as a main component, with respect to the thermoplastic resin as a component (A). It is good to mix with.
When the content of the component (B) is less than 0.01%, the effect of improving the freshness of the food, the effect of suppressing the offensive odor, and the effect of maintaining the taste of the contents are not sufficient. On the other hand, when it exceeds 10%, the appearance of the molded product is deteriorated and the impact resistance and chemical resistance are poor.
It is preferably in the range of 0.02 to 9.5%, particularly preferably in the range of 0.04 to 9.0%.

The composition of the present invention may be prepared by dry blending the components (A) and (B) during molding, and the blended product of the above components may be mixed with a mixer such as a tumbler or a mixer. Then, a method of mixing and then kneading using a mixer such as a Banbury mixer, a kneader, or an extruder can be used. Alternatively, they may be mixed with an open roll or the like. Since the component (B) contains the volatile component and easily secondary-aggregates as described above, the temperature of the component (B) should be 5
Vacuum drying at 0 ° C. or higher for a day or longer is preferable because the dispersibility is improved. In addition, a masterbatch in which the component (B) is blended at a high concentration may be used by a method used for improving dispersibility. Generally, the mixing temperature is 160 to 300 ° C.
And 180 to 280 ° C is preferable. The composition of the composition thus prepared has a melt flow rate (measured in accordance with JIS K7210 at a temperature of 230 ° C. and a load of 2.16 Kg, hereinafter referred to as “MFR”) of 0.1 to 300 g / 1.
Must be 0 minutes, 0.2-250 g / 10
Minutes are preferable, and 0.3 to 200 g / 10 minutes is particularly preferable. If the MFR is less than 0.1 g / 10 minutes, the moldability will be poor. On the other hand, if it exceeds 300 g / 10 minutes, it tends to be difficult to thicken the product.

Further, for the resin composition of the present invention, other additives conventionally used in thermoplastic resins (for example, antioxidant,
A weather resistance stabilizer, an antistatic agent, a lubricant, an anti-blocking agent, an antifogging agent, a dye, a pigment, an oil, a wax, etc.) can be added in an appropriate amount within the range not impairing the object of the present invention. For example, examples of such additives include 2,5-di-t-butylhydroquinone and 2,6-di-
t-butyl-p-cresol, 4,4'-thiobis-
(6-t-butylphenol), 2,2-methylene-bis (4-methyl-6-t-butylphenol), octadecyl-3- (3 ', 5'-di-t-butyl-1'-hydroxyphenyl) Propinate, 4,4′-thiobis- (6-butylphenol), as an ultraviolet absorber, ethyl-2-cyano-3,3-diphenylacrylate,
2- (2'-hydroxy-5-methylphenyl) benzotriazole, 2-hydroxy-4-octoxybenzophenone, dimethyl phthalate as a plasticizer, diethyl phthalate, wax, liquid paraffin, phosphate ester,
As the colorant, phthalocyanine, quinacridone, indoline, azo pigments, titanium oxide, red iron oxide, etc., and many other polymer compounds can also be blended to the extent that the effects of the present invention are not impaired.

From the resin composition of the present invention obtained as described above, a container or film is formed using a known T-die molding method, inflation molding method, injection molding method, blow molding method, calender molding method and molding machine. And the like can be obtained. In film / sheet molding, the temperature of the extruder is usually 180 ° in the case of T-die film / sheet molding.
To 300 ° C, preferably 200 to 290 ° C, and particularly preferably 220 to 280 ° C. Also,
The temperature of the cooling roll may be in the range of 10 to 80 ° C, preferably 20 to 70 ° C, and particularly preferably 30 to 60 ° C. On the other hand, in the case of blown film molding, the temperature of the extruder is 150 to 250 ° C., preferably 16
It is good to carry out in the range of 0 to 230 ° C., particularly preferably 170 to 220 ° C., and the blow-up ratio of 1.5 to 8. In the case of injection molding, the temperature is 150 to 300 ° C, preferably 160 to 280 ° C, particularly preferably 170 to 260.
It is good to carry out in the range of ° C.

In blow molding, the temperature of the extruder is 150.
˜250 ° C., preferably 160 to 230 ° C., particularly preferably 170 to 220 ° C. The calender molding method has a temperature of 150 to 230 ° C., preferably 160 to 230 ° C.
It is good to carry out at 210 ° C., particularly preferably in the range of 170 to 200 ° C. Further, the molded product of the present invention may be used alone or laminated with other materials by various laminating methods and various coextrusion molding methods. The article to be housed in a molded article composed of the thermoplastic resin composition of the present invention, or to be wrapped with a film or the like may be any, for example, fruits and vegetables, processed foods, meats, foods such as fish, syringes, needles, Drip device,
Examples include medical supplies such as absorbent cotton and sutures.

[0021]

EXAMPLES The contents of the present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. (Examples 1 to 10 and Comparative Examples 1 to 9) [Type of thermoplastic resin as component (A)] R-1: Density 0.926 g / cm ³ , MFR 0.7 g /
Linear polyethylene R-2 for 10 minutes (temperature 190 ° C., load 2.16 Kg): ethylene content 3.5% by weight, MFR 6.2 g
/ 10 minutes (temperature 230 ° C., load 2.16 Kg) ethylene-propylene random copolymer R-3: propylene content 43% by weight, ethylene-propylene rubber content 20% by weight, MFR 1.4 g / 1
0 minutes (temperature 230, load 2.16Kg) propylene block copolymer

Minerals containing tuff sandstone as the main component used in the examples (minerals mixed with clay in the tuff sandstone. "SGE" powder manufactured by Only Chemical Co., Ltd.) and natural sedimentary rocks of the comparative example (green The components of tough (green tuff, "Otaniishi" from Utsunomiya, Tochigi Prefecture) are shown below. * The total amount of Ni, Rb, Sb, Cs, Pb, Bi, Y, La, Ba, Zn, Cu elements as the element content

[Mixing of Polymer and Additive] The above components (A) and (B), and components (A) and (B ') are mixed using a Henschel mixer, respectively, and are mixed in the same direction manufactured by Kobe Steel, Ltd. Using a twin-screw extruder (KTX-37 type), pelletization was performed at a temperature of 160 to 210 ° C. The following various physical properties were evaluated by appropriately changing the combination and blending amount of the component (A) and the component (B) and the component (A) and the component (B '). The results are shown in Table 1. [Inflation film molding] Regarding the resin composition using R-1 in the component (A), an extruder with a diameter of 50 mmφ manufactured by Yoshii Iron Works Co., Ltd., an extrusion temperature of 190 ° C.,
An inflation film having a folding width of 270 cm and a thickness of 40 μm was prepared at a take-up speed of 35 m / min.

[Cast Film Molding] The resin composition using R-2 and R-3 of the above-mentioned component (A) was cast with a thickness of 60 μm using an extruder with a diameter of 40 mmφ and a T-die manufactured by Yoshii Iron Works Co., Ltd. I made a film. [Evaluation of Appearance of Film] The films of Comparative Examples 5, 7, and 9 all had a large amount of gel and fish eyes, and a flow pattern that was considered to be caused by adsorbed moisture was generated. On the other hand, in each of the examples of the present invention, a clean film could be obtained.

The method and apparatus for measuring each physical property in the present invention are shown below. Analysis of mineral components Rigaku Corporation fluorescent X-ray analyzer (Rh X-ray tube, 60KV-
2 mA). Gas Permeation Test Using a LYSSY mixed gas permeability tester GPM-500, the permeation amounts of oxygen gas and carbon dioxide gas were measured. Freshness retention test Using the film formed as described above, one of various films was heat-sealed and then cut to a length of 450 cm, and Ome was put into the film, which was then stored for 9 days to evaluate appearance, mold generation, and odor. The occurrence status was evaluated. The evaluation method was as follows. [Appearance evaluation criteria] ◎ ・ ・ ・ ・ Green ○ ・ ・ ・ ・ Yellowish green △ ・ ・ ・ ・ Yellow green × ・ ・ ・ ・ Yellow yellowish green XX ・ ・ ・ Yellow (completely yellowed) ) [Generation of mold] After storage, the bag was opened and the number of molds was measured. [Measurement of Odor] The bag was opened after storage, and the unpleasant odor at the time of opening was evaluated according to the following criteria. ○ ・ ・ ・ ・ No offensive odor at all. △ ・ ・ ・ ・ Slight offensive odor was generated. × ・ ・ ・ ・ A remarkable odor is generated.

Evaluation of gamma ray irradiation odor 20 g of each film was put in a glass bottle having an internal volume of 100 ml, sealed, and gamma of 2.5 Mrad with a cobalt 60 radiation source.
The line was irradiated. The gas in the glass bottle irradiated with γ rays in this manner was sampled with a 1 cc gas tight syringe, and the amount of acetic acid generated was quantified using gas chromatography Shimadzu GC-7A type, detector FID, and capillary column FFAP. Next, 20 cm from each film
After making a pouch of × 20 cm and heat-sealing, a 2.5 Mrad γ ray was irradiated to perform a odor sensory test. In the odor sensory test, the following criteria were evaluated. 1 ・ ・ ・ No feeling 2 ・ ・ ・ Slight feeling 3 ・ ・ ・ Fair feeling 4 ・ ・ ・ Slightly strong 5 ・ ・ ・ Strong feeling Taste after retort sterilization 20 cm x 2 for a film based on odor evaluation R-3
Create a 0 cm pouch, fill it with 100 ml of tap water, and use a Hisaka Seisakusho retort tester at a temperature of 121
After retort treatment at 30 ° C. for 30 minutes and cooling, a taste sensory test and an odor sensory test according to the following criteria were performed.

[Taste sensory test criteria] 1 ... Mellow and rich 2 ... I have no body, but the taste is not bad 3 ... I don't feel well [Odor sensory test criteria] 1 ... I don't feel it at all 2 ... I feel a little 3 ... I feel quite 4 ... Feels somewhat strong 5 ... Feels intense The above results are shown in Table 1.

[0028]

[Table 1]

[0029]

EFFECTS OF THE INVENTION The resin composition of the present invention has an appropriate gas permeability and a high CO ₂ / O ₂ selective permeation ratio, so that it has a freshness-keeping effect on fruits and vegetables and has a prolonged storage period. However, it is possible to minimize post-harvest pretreatment steps, simplify packaging operations, and improve the commercial value of fruits and vegetables. Therefore, the present invention can be widely used as an effective technique for maintaining the freshness of fruits and vegetables. Further, it suppresses the generation of offensive odors upon irradiation with ionizing radiation, and is therefore suitable as a packaging material for medical use. It also improves the taste of fresh fish, meats, processed foods, etc., and is therefore effective as a packaging material for various foods.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-33723 (JP, A) JP-A-10-279729 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08L 1/00-101/16

Claims (7)

(57) [Claims] 1. A thermoplastic resin composition comprising (A) a thermoplastic resin and (B) a fine powder of a mineral containing tuff sandstone as a main component. 2. The thermoplastic resin composition according to claim 1, wherein the amount of fine powder of mineral containing tuff sandstone as a main component is 0.01 to 10% by weight. 3. The thermoplastic resin composition according to claim 1, wherein the thermoplastic resin is a polyolefin resin. 4. The thermoplastic resin composition according to claim 1, wherein the mineral containing tuff sandstone as a main component has the following component composition. SiO ₂ 60 to 75 wt%, Al ₂ O ₃ 6 to 21 wt%, MgO 0.5 to 4 wt%, CaO 1 to 4 wt%, Fe ₂ O ₃ 1 to 4 wt%, Na ₂ O 0.8 6 wt%, K ₂ O 0.5 to 4 wt% 5. A fine powder of mineral containing tuff sandstone as a main component has an average particle size of 0.1 to 20 μm and a specific surface area of 50 m ² /
The thermoplastic resin composition according to any one of claims 1 to 4, wherein the thermoplastic resin composition has a g or less and a pore volume of 1.0 cm ³ / g or less. 6. A food packaging or storage material comprising the thermoplastic resin composition according to claim 1. 7. A packaging or storage material for medical supplies, which comprises the thermoplastic resin composition according to claim 1.