JP2001181430A - Deodorant expandable styrene-based resin composition and molded product thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a molded product of a deodorant expandable styrene-based resin having high deodorant effects on various kinds of odors and capable of stably sustaining the effects for a long time and a deodorant expandable styrene-based resin composition which is a raw material of the molded product. SOLUTION: This deodorant expandable styrene-based resin composition comprises an expandable styrene-based resin and at least one or more kinds of four kinds of deodorants composed of a specific tetravalent metallic phosphate, a specified composite metallic phosphate, a hydrotalcite compound, a porous silicon dioxide supporting a specified polyamine and the like. The molded product is obtained by molding the composition under heated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foamed styrenic resin article having a deodorizing function for use in various applications including food packaging and a deodorant foamable styrenic resin composition as a raw material thereof. It is.

[0002]

2. Description of the Related Art As is well known, a foamable styrene resin is prepared by dispersing an aliphatic hydrocarbon having a high volatility at room temperature, such as propane, butane, or pentane, in an aqueous medium together with a styrene resin pellet and impregnating the pellet. After that, it is manufactured by a method of heating. Then, the obtained expandable styrene resin is heated with heated steam, filled into a mold having pores after primary foaming, and heated foam is injected from the pores to form a foamed article by secondary foaming. .

[0003] The foamable styrenic resin molded article manufactured in this manner is inexpensive, lightweight and excellent in heat insulation, so that various containers and boxes for heat insulation and heat insulation, heat insulation materials,
Widely used as packing materials or various cushioning materials. In applications where these containers and packing materials come into contact with odorous articles, a function to remove the odor is required. For example, in the case of containers for foods such as fruits and fresh fish, or when these foods are packed together with packing materials, cushioning materials, etc., the odor generated from the foods and the like is generated on the molded article of the expanded styrene resin. Even after the transfer and the removal of the food or the like, the odor remains in the expanded styrene-based resin molded article, which poses a serious problem when the above-mentioned container or packing material is used for another kind of food. It is also desired that a foam molded article to be inserted into a shoe used to prevent the shape of the shoe has a function of eliminating the odor of the shoe.

In order to solve these problems, Japanese Patent Application Laid-Open No. 63-150
No. 353 proposes to include calcareous diatomaceous earth or the like in the styrofoam resin molded article, but the deodorizing performance is not sufficient, and when the adsorption capacity of the deodorant approaches the limit, the malodor once deodorized is reduced. It was released again and sometimes smelled. Further, Japanese Patent Application Laid-Open No. 8-120112 proposes that a foamed styrene resin molded article contains a metal phthalocyanine derivative, but it cannot be said that the deodorizing performance is sufficient.

[0005]

DISCLOSURE OF THE INVENTION The present invention relates to a deodorizing foamable styrenic resin molding which has a high deodorizing effect for various odors when used in various application fields, and which can stably maintain the effect for a long period of time. An object of the present invention is to provide an expandable styrene resin composition as a body and its raw material.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and have found that a styrene-based resin composition comprising an expandable polystyrene-based resin and a specific deodorant is extremely effective. As a result, the present invention has been completed. That is, the present invention provides an expandable polystyrene resin and a specific tetravalent metal phosphate, a composite metal phosphate obtained from the tetravalent metal phosphate, a hydrotalcite compound or a calcined product thereof, hydrated zirconium oxide. Or a deodorant foamable polystyrene-based resin composition comprising at least one deodorant selected from porous silicon dioxide carrying zirconium oxide and a specific polyamine compound, and the resin composition Of a foamed polystyrene-based resin molded article obtained by molding under heat.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

消 Deodorant The deodorant in the present invention includes the following deodorant a, deodorant b,
At least one selected from deodorant C and deodorant D
Species, all of which are compounds with extremely low toxicity to the human body.

(Deodorant A) The deodorant A is a hydrogen-containing tetravalent metal phosphate represented by the above general formula [1]. This deodorant A exhibits excellent deodorizing properties against amine compounds such as trimethylamine, triethylamine and pyridine and basic gases such as ammonia. Specific examples of the tetravalent metal M in the above formula [1], which have a high deodorizing effect and are preferable, include zirconium, titanium,
There are tin, cerium, hafnium, etc., zirconium,
Titanium is more preferred. The coefficients a, b, c and d of the formula [1] in the deodorant A have a relationship of a + 4b = 2c + 3d, and the preferable coefficients are the following numerical values. a = 1, b = 1, c = 1, d = 1 a = 1, b = 2, c = 0, d = 3 a = 2, b = 1, c = 0, d = 2

The tetravalent metal phosphate represented by a = 1, b = 1, c = 1, and d = 1 is a compound which is easily obtained as amorphous fine particles having an average particle diameter of 1 μm or less. , B = 2,
The tetravalent metal phosphate represented by c = 0 and d = 3 is a NASICON-type crystalline compound or an amorphous compound. Furthermore, a
= 2, b = 1, c = 0, d = 2 are classified into crystalline compounds having a layered structure and amorphous compounds, and the former are α-type crystals. Monohydrates, anhydrous salts that are β-type crystals, and dihydrates that are γ-type crystals are included. Particularly preferred tetravalent metal phosphate represented by the above formula [1] has a large crystal interlayer distance and a high deodorizing speed.
α-type crystal monohydrate and γ-type crystal dihydrate having coefficients of a = 2, b = 1, c = 0 and d = 2.

Preferred specific examples of the deodorant a include the following compounds. _{HTiO (PO 4) HZrO (PO} 4) HZr 2 (PO 4) 3 · H 2 O HTi 2 (PO 4) 3 · H 2 O HSn 2 (PO 4) 3 · 3H 2 O H 2 Zr (PO 4) _{2 H 2 Zr (PO 4)} 2 · H 2 O H 2 Zr (PO 4) 2 · 2H 2 O H 2 Ti (PO 4) 2 · 2H 2 O H 2 Sn (PO 4) 2 · H 2 O

(Deodorant B) The deodorant B is a composite metal phosphate represented by the above general formula [2], and contains a monovalent metal and / or a divalent metal and a tetravalent metal in its molecule. Is a compound containing The deodorant b has excellent deodorizing properties against sulfur-containing gases such as hydrogen sulfide and methyl mercaptan, and lower fatty acids such as acetic acid, valeric acid and butyric acid. Preferred specific examples of the tetravalent metal M in the above formula [2] include zirconium, titanium, tin, cerium, hafnium and the like, with zirconium and titanium being more preferred. The composite metal phosphate represented by the above formula [2] is obtained by substituting a part or all of the hydrogen of the tetravalent metal phosphate represented by the above formula [1] with a monovalent or divalent metal. Phosphate having a structure, as a preferred specific example of the monovalent or divalent metal,
Lithium, sodium, potassium, cesium, magnesium, calcium, strontium, barium, copper,
There are iron, zinc, nickel, manganese and cobalt.
Among them, sodium, potassium, copper, zinc and manganese are preferable because of their high deodorizing effect.

It is preferable that the coefficients a, b, c, d, e and f in the deodorant b satisfy the following formula (where a, b and c may be 0, and b and c
Do not become 0 at the same time). a + b + 2c = 1, d = 1, e = 1, f = 1 a + b + 2c = 1, d = 2, e = 0, f = 3 a + b + 2c = 2, d = 1, e = 0, f = 2 Particularly preferable among them Is given by the equation (a + b + 2c =
2, d = 1, e = 0, f = 2)
a, b and c may be 0, and b and c are not simultaneously 0).

Since the tetravalent metal phosphate represented by the above formula [1] has a cation exchange property, the composite metal phosphate represented by the formula [2] is A part of hydrogen in the phosphate can be easily obtained by ion-exchange with a monovalent metal and / or a divalent metal and carrying the same. Specifically, the tetravalent metal phosphate represented by the above formula [1] is easily supported by bringing it into contact with an aqueous solution containing a salt or hydroxide of a monovalent metal and / or a divalent metal. Can be. When two or more metals are supported, they may be supported by one-time ion exchange using an aqueous solution containing two or more metals, or may be supported by multiple times of ion exchange. When a monovalent metal and a divalent metal are supported, if the divalent metal is supported first after supporting the monovalent metal, ion exchange can be performed efficiently.

The supported amount of the monovalent metal and / or the divalent metal is as follows:
If it is within the ion exchange capacity of the tetravalent metal phosphate (deodorant a) represented by the above formula [1], it can be freely controlled up to 100% as desired. In order to exhibit sufficient deodorizing properties against lower fatty acids and the like, the amount of the supported metal is set to 25% of the ion exchange capacity (for example, the deodorant A is H ₂ Zr (PO ₄ ) ₂ .2H). _{In the case of 2} O, that is, α-type zirconium phosphate, 1.6 milligram equivalent /
g) or more, more preferably 50% or more (3.2 milligram equivalent / g when the deodorant a is α-zirconium phosphate).

The complex metal phosphate represented by the formula [2] includes a water-soluble one, but in the present invention, a water-insoluble or sparingly water-soluble one is preferable. On the other hand, since the deodorant b having hydrogen ions has a deodorizing property for basic gas, if it is desired to simultaneously deodorize the basic gas together with the sulfur-containing gas or lower fatty acid, etc. Alternatively, it becomes possible by appropriately adjusting the amount of the supported divalent metal within a range of less than 100% of the ion exchange capacity and leaving hydrogen ions.

(Deodorant C) The deodorant C is at least one compound selected from a hydrotalcite compound or a calcined product thereof, hydrated zirconium oxide, and zirconium oxide. This deodorant c is formaldehyde,
It exhibits excellent deodorizing properties to aldehydes such as acetaldehyde and lower fatty acids such as acetic acid, valeric acid and butyric acid.

The hydrotalcite compound is a compound having a so-called hydrotalcite structure represented by the following general formula [4], and the most preferred compound is magnesium-aluminum hydrotalcite. M ¹ _(1-x) M ² _x (OH) ₂ An _{(x / n)} · mH ₂ O [4] (M ¹ is a divalent metal, M ² is a trivalent metal,
x is a number greater than 0 and equal to or less than 0.5; An is an n-valent anion such as a carbonate ion or a sulfate ion;
Is a positive number. )

The calcined product of hydrotalcite is a compound obtained by calcining a hydrotalcite compound at a temperature of about 500 ° C. or higher and removing carbonate groups and hydroxyl groups.

The hydrated zirconium oxide may be either crystalline or amorphous, and is a compound having the same meaning as zirconium oxyhydroxide, zirconium hydroxide, hydrous zirconium oxide and zirconium oxide hydrate. The hydrated zirconium oxide in the present invention is a known compound, and its production method is not particularly limited. As a preferred production method, there is a wet method, and hydrated zirconium oxide can be easily obtained by hydrolyzing a zirconium-containing aqueous solution such as an aqueous zirconium oxychloride solution with water or an aqueous alkali solution.

The zirconium oxide may be either crystalline or amorphous, but is preferably amorphous in order to exhibit high deodorizing properties. As the zirconium oxide in the present invention, a commercially available product may be used as it is, or an anhydride obtained by calcining the above hydrated zirconium oxide may be used. The preferable firing temperature for firing amorphous hydrated zirconium oxide to obtain amorphous zirconium oxide is 150 ° C to 350 ° C.
It is.

(Deodorant D) The deodorant D is a porous silicon dioxide carrying a specific polyamine compound represented by the above chemical formula [3]. This deodorant exhibits excellent deodorizing properties against aldehyde gases such as formaldehyde and acetaldehyde. Porous silicon dioxide specific surface area is carrier is preferably ^{400~900m 2 / g, 500~900m 2 /} g is more preferable. If the specific surface area is less than 400 m ² / g, the contact area between the polyamine compound and the aldehyde gas decreases, and the gas adsorption amount is impaired. If the specific surface area is larger than 900 m ² / g, too much polyamine compound is adsorbed, and when processed into a foamed polystyrene resin, it tends to cause discoloration by heating. The specific surface area can be easily measured by the BET method calculated from the nitrogen adsorption amount.

The average pore diameter of the porous silicon dioxide is preferably from 0.1 to 10 nm, more preferably from 2 to 8 nm. If the average pore diameter is too large, the specific surface area decreases, the amount of the polyamine compound supported decreases, and the adsorption performance of the aldehyde gas decreases. If an attempt is made to make the specific surface area sufficiently large despite the fact that the average pore diameter is too large, the porosity of the porous body becomes too large, the mechanical strength becomes small, or the ability to support the polyamine compound becomes weak. However, there is a problem that the polyamine compound is released by a slight heating. On the other hand, if the average pore diameter is too small, the specific surface area of silicon dioxide increases, but it becomes difficult for the polyamine compound to enter the pores. As a result, the amount of the polyamine compound carried cannot be increased, and the gas absorption capacity decreases. The average pore diameter (D) is easily calculated from the pore volume and the specific surface area obtained by the BET method using the following formula. D = 4 × V / Sc × 104 (where V represents the pore volume [ml / g] and Sc represents the specific surface area [m ² / g])

The water content of the porous silicon dioxide is 0.1.
It is preferably from 5 to 20% by weight, more preferably from 8 to 15% by weight. The water content of silicon dioxide is
It can be easily measured according to JISK7120-7122. When the water content is less than 0.5% by weight, the supporting force on the polyamine compound in the present invention is small because the surface has few silanol groups. Conversely, when the water content is more than 20% by weight, it causes coloring and deterioration when processed into a foamed styrene resin. Commercially available products of porous silicon dioxide include, for example, silica gel and nip seal (fine particle hydrous silicon dioxide).

The polyamine compound has a primary amino group in the molecule and is represented by the above chemical formula [3]. The preferable loading amount of the polyamine compound on silicon dioxide is 0.02 to 2 mmol / g. If the supported amount is too small, the adsorption capacity of the aldehyde gas decreases, and if the supported amount is too large, the polyamine compound jumps out of silicon dioxide when processing into a foamed styrene-based resin, causing discoloration, and the polyamine compound. The odor itself becomes bad. Also, the amount of aldehyde gas adsorbed decreases. The supported amount of the polyamine compound can be easily calculated from the nitrogen content detected by organic element analysis.

In the resin composition of the present invention, when it is necessary to simultaneously deodorize gases having different properties such as a basic gas, a sulfur-containing gas, an aldehyde gas, and a lower fatty acid gas, the above deodorization is carried out. It is preferable to use two or more agents in combination. When two or more deodorants are used in combination, there is no particular limitation on the combination ratio of each deodorant, and the mixing ratio may be appropriately adjusted depending on the type of gas to be deodorized. When the deodorant foamable styrenic resin molded article according to the present invention is used for packaging or contacting an article generating a certain odor, the most suitable among the four types of deodorants used in the present invention. The deodorant effect can be maximized by combining one or more deodorants. When it is not possible to predict what kind of odor is to be brought into contact, or when it is to be brought into contact with many kinds of odor-generating substances at the same time, it is preferable to use a composition containing all four of these.

[0027] The four types of deodorants used in the present invention can deodorize by adsorbing a specific odor-causing substance corresponding to each, and further reacting with the chemical substance. The effect is very strong and stable for a long time. The deodorant in the present invention is usually obtained in the form of powder, and preferably has an average particle size of 0.01 to 20 μm.
m, more preferably 0.01 to 10 μm,
More preferably, it is 0.01 to 5 μm. If the average particle size is less than 0.01 μm, it is likely to re-agglomerate and the handling may be difficult. If the average particle size is more than 20 μm, the deodorant particles may be used as the expandable styrene resin composition or the expandable styrene resin. There is a possibility that the resin may easily fall off from the resin molded body.

The deodorant of the present invention is stable even when heated at about 200 ° C. or exposed to ultraviolet light, without any change in structure and composition, and no discoloration. Therefore, there is no restriction such as temperature control and light shielding for preventing the deodorant from deteriorating during processing, storage, and use when producing the expandable polystyrene resin molded article of the present invention.

The method of obtaining a deodorant foamable styrene resin composition comprising a foamable styrene resin and a deodorant includes a method of simply mixing the foamable styrene resin with a deodorant at ordinary temperature, a method of foaming. A method of attaching a deodorant to the surface of the styrene resin via another substance, a method of heating and melting the expandable styrene resin and kneading the deodorant, and the like are possible. The time when the deodorant is mixed or attached may be before the foamable resin is primarily foamed or before the foamable resin is foamed secondarily. In addition, in order to enhance the adhesion of the deodorant to the surface of the foamable resin particles, or as another auxiliary agent added simultaneously with the deodorant, the synthesis of the particles of the foamable resin particles is performed. An anti-adhesion agent, a lubricant for facilitating the filling of the foamable resin into the mold, a fusion promoter during molding, a molding cooling time shortening agent, an antistatic agent, a coloring agent, and the like can be used. Specifically, talc, calcium carbonate, colloidal silica, alumina, ethylenebisstearamide, higher fatty acids, higher fatty acid amides, higher fatty alcohols, edible oils, oils and fats, higher fatty acid monoglycerides, paraffin wax, polyethylene wax, stearic acid Zinc and the like can be mentioned.

In order to mix and attach the deodorant to the styrene resin, the deodorant and the styrene resin may be stirred and vibrated in a mixer. As the mixer, a ribbon blender, a tumbler, a Laige mixer, a Nauta mixer, a super mixer, or the like can be used.

The amount of the deodorant used in the deodorant foamable styrene resin composition is determined based on the amount of the foamable polystyrene resin 10.
The amount of the deodorant is preferably from 0.01 to 10.0 parts by weight, more preferably from 0.1 to 5.0 parts by weight, per 0 parts by weight.
If the amount is less than 0.01 part by weight, it is difficult to exert sufficient deodorizing performance. If the amount exceeds 10.0 parts by weight, the strength of the foamed molded article is remarkably reduced, or the deodorant is used as a resin. And it is difficult to uniformly mix the particles with the surface of the particles and to uniformly attach the particles to the surface of the particles. Further, in the present invention, a flame retardant may be added in addition to the deodorant, if necessary, to give flame retardancy.

Styrene resin The styrene resin used in the present invention is a styrene monomer alone or a copolymer with another monomer. Examples of the styrene-based monomer include styrene, p-methylstyrene, vinyltoluene, t-butylstyrene, and the like. Examples of copolymerizable comonomers include acrylonitrile, methacryl acrylate, maleic anhydride, acrylic acid, methacrylic acid, and N-phenylmaleimide. These styrene resins are polymerized by a known method. Among them, a homopolymer of a styrene-based monomer and a styrene-acrylonitrile copolymer resin can be suitably used because a high-magnification foam can be easily obtained by one-time heating and foaming. In the present invention, it is preferable to use the resin composed of these homopolymers or copolymers in the form of particles. The shape of the styrene-based resin particles used in the present invention is not particularly limited, but a pearl shape (spherical shape), an elliptical shape, a pellet shape (column shape) and the like can be preferably used. The particle size is generally used as expanded styrene resin beads, and the particle size of commercially available beads can be used. The preferred particle size is 0.3 to 3.0 mm, and the particularly preferred particle size is 0.5. １．５1.5 mm.

Blowing agent As the blowing agent used in the present invention, a general blowing agent used for producing a expandable resin, for example, an easily volatile blowing agent of an aliphatic hydrocarbon or a halogenated hydrocarbon may be used alone. Or a mixture of two or more. Specific examples of the aliphatic hydrocarbon include, for example, propane, n-butane, isobutane, n-pentane, isopentane, cyclopentane and the like. Further, specific examples of the halogenated hydrocarbon, for example, trichloromonofluoromethane,
Dichlorodifluoromethane, monochlorotrifluoromethane, dichloromonofluoromethane, monochlorodifluoromethane, trichlorotrifluoroethane, dichlorotetrafluoroethane, monochloropentanefluoroethane, monochlorotetrafluoroethane, monochlorotrifluoroethane, monochlorodifluoroethane, tetrafluoroethane, difluoroethane And the like.

The means for incorporating the foaming agent into the styrene resin is not particularly limited, and a known method conventionally used may be used. For example, when producing a styrenic resin by an aqueous suspension polymerization method, a method in which a blowing agent is added during the polymerization and polymerization and impregnation are simultaneously performed,
A method in which styrene-based resin particles are made into an aqueous suspension state, and a foaming agent is added and impregnated into the suspension, or an extruder is used to impregnate the styrene-based resin with the foaming agent and then extruded in an unfoamed state to pelletize the same. Etc. After subjecting the styrene resin impregnated with the blowing agent obtained by these methods to means such as dehydration, drying and aging, an expandable styrene resin can be obtained.

The foaming styrene resin of the present invention preferably contains 1 to 8 parts by weight, more preferably 2 to 6 parts by weight of a foaming agent per 100 parts by weight of the styrene resin. When the amount of the foaming agent is more than 8 parts by weight, it is difficult to impregnate the resin uniformly with the foaming agent, and it is easy to form an uneven foam. On the other hand, if the amount of the foaming agent is less than 1 part by weight, the necessary heat insulating effect and buffering effect cannot be obtained due to insufficient foaming rate.

Uses The deodorant foamable styrenic resin composition of the present invention and the molded article thereof are generally used for foamable styrenic resins, and are particularly used in applications where odor is a problem. Is done. Specifically, cool boxes such as fish boxes and vegetable boxes, cushioning materials for various packing, internal parts of home appliances such as air conditioners and refrigerators, building wall materials, floor materials, ceiling materials, shoe insoles, leisure Seats, pet seats, pet houses, and the like are included.

Molding method The molding method for obtaining a molded article for the above application from the defoamable foamable styrenic resin composition of the present invention includes injection molding, molding, extrusion molding, T-die method, vacuum molding and the like. It can be used, and in particular, the injection molding method and the mold molding method can be used for a wide range of applications. For example, in the molding of a mold that is frequently used in applications such as packaging materials and building materials, a deodorizing foamable styrenic resin composition is put into a mold and heated steam is blown or the mold is foamed by heating to mold. Any of a two-step method and a two-step method in which the deodorant expandable styrenic resin composition is sufficiently foamed by a prefoaming machine and then put into a mold and molded, can be used.

[0038]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to examples.

[Example 1] A particle diameter of 1 m was added to a super mixer.
m expandable styrene resin particles (Eslen beads, Sekisui
150 g with polyethylene glycol
Of polystyrene resin particles.
The surface was covered with polyethylene glycol. In addition,
Tetravalent metal phosphate H, a kind of odorant a_TwoZr (P
O_Four)_Two・ 2H _TwoFurther add 1.5 g of O [] and stir,
[] Was adhered to the surface of the styrene resin particles. Then
This is pre-foamed at a temperature of 126 ° C by a heating pre-foaming machine.
After curing for 24 hours, width 30cm, height 30cm, thickness
Fill into a mold for molding foaming resin plate of 3cm in length,
Water vapor is blown into this mold and again at a temperature of 126 ° C.
Expanding of styrene resin with about 50 times expansion ratio by expanding
I got a body.

[Examples 2 to 4] In Example 1, the deodorant was used.
A foam molded article was obtained in the same manner as in Example 1 except that deodorants [] to [] in Table 1 were added instead of [].

[0041]

[Table 1]

[Example 5] In Example 1, instead of adding 1.5 g of the deodorant [], the deodorant [] was used instead of 6.
A foam molded article was obtained in the same manner as in Example 1 except that 0 g was added.

[Comparative Example 1] Foaming was performed in the same manner as in Example 1 except that activated carbon (Kuraray Coal GC-3H manufactured by Kuraray Co., Ltd.) was added instead of adding the deodorant []. I got a body.

Comparative Example 2 A foam molded article was obtained in the same manner as in Example 1 except that no deodorant was added.

O Deodorizing Test Method A 10 cm long, 10 cm wide, and 3 cm thick plate was cut out from the foamed molded product obtained in each of the examples and comparative examples, placed in seven Tedlar bags, and sealed. A test gas of a predetermined concentration was injected into each Tedlar bag by 1 L. Two hours later, the gas concentration in each Tedlar bag was measured using a detector tube (manufactured by Gastech Co., Ltd.), and the results are shown in Table 3.

[0046]

[Table 2]

[0047]

[Table 3] As is clear from the results in Table 3, it can be seen that the foamed molded article obtained by molding the defoamable foamable resin composition according to the present invention has excellent deodorizing performance.

[0048]

The molded article of the deodorant foamable styrenic resin of the present invention is excellent in the function of deodorizing various odors, and is useful in applications where it comes in contact with substances that generate odors such as malodors. The deodorant foamable styrenic resin composition of the present invention is useful as a raw material for forming the above-mentioned molded article.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 25/02 C08L 25/02

Claims (4)

[Claims] 1. A deodorant foamable styrene resin composition comprising a foamable styrene resin and at least one of the following deodorants a, b, c and d. Deodorant A: tetravalent metal phosphate represented by the following chemical formula [1]. H _a M _b O _c (PO ₄ ) _d · nH ₂ O [1] [M is a tetravalent metal, and a, b, c and d are represented by the formula (a + 4)
b = 2c + 3d) is a positive number (however, c may be 0), and n is 0 or a positive number. Deodorant b: a composite metal phosphate represented by the following chemical formula [2]. _{H a A b B c M d} O e (PO 4) f · nH 2 O [2] [A is a monovalent metallic, B is a divalent metal, M is a tetravalent metal, a, b , C, e and n are 0 or positive numbers, and d and f are positive numbers. Further, a, b, c,
d, e, and f are expressed by the formula (a + b + 2c + 4d = 2e + 3)
f) is satisfied, and b and c do not become 0 at the same time. Deodorant C: hydrotalcite compound or its calcined product, hydrated zirconium oxide, or zirconium oxide. Deodorant d: porous silicon dioxide supporting a polyamine compound represented by the following chemical formula [3]. H ₂ N— (CH ₂ CH ₂ —NH) _n —CH ₂ CH ₂ NH ₂ [3] (where n represents an integer of 0 or more and 3 or less) 2. An expandable styrenic resin and said deodorant a.
2. The deodorant foamable styrenic resin composition according to claim 1, comprising b, c and d. 3. The amount of the deodorant is 10 when the foamable styrenic resin 10 is used.
The deodorant foamable styrenic resin composition according to claim 1 or 2, which is 0.01 to 10.0 parts by weight per 0 parts by weight. 4. A deodorizable foamable styrenic resin molded article obtained by molding the deodorant foamable styrenic resin composition according to claim 1, 2 or 3 under heating.