JP2005325218A - Polyurethane foam molded article and pad for seat - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyurethane foam molded article from which the evaporation of an aldehyde compound is reduced as a countermeasure against VOC (volatile organic compounds), and to provide a pad for a seat. <P>SOLUTION: This polyurethane foam molded article prepared by foaming and molding a polyurethane foam raw material containing a thiosulfate, and a pad comprising the polyurethane foam molded article and used for a seat. Since aldehyde compounds such as acetaldehyde and formaldehyde are reduced with the thiosulfate, the evaporation of the aldehyde compound can be reduced to prevent a nasty smell. Sodium thiosulfate is preferable as the thiosulfate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polyurethane foam molded article and a sheet pad with reduced generation of aldehydes.

  In recent years, as a cause of sick house syndrome, it has been required to reduce volatile organic compounds (VOCs) such as aldehydes in the housing field, and VOC countermeasures have become necessary even in the automobile field.

  For example, a polyurethane foam molded body is generally used for a seat pad of an automobile, but since such a polyurethane foam generates a strange odor due to aldehydes such as acetaldehyde and formaldehyde, such a measure is taken as a measure against VOC. It is required to reduce the generation of aldehydes.

Conventionally, in order to reduce off-flavors generated from polyurethane foam, for example, Patent Document 1 below discloses phosphoric acid, phosphorous acid, hypophosphorous acid, chloric acid, chlorous acid, hypochlorous acid, or salts thereof. A deodorized polyurethane foam containing a deodorizing component containing at least one selected from the above is disclosed. Patent Document 2 below discloses a technique for reducing off-flavors by reducing aldehydes by adding sodium tetrahydroborate (NaBH ₄ ) or the like to a polyurethane resin.
Japanese Patent Laid-Open No. 3-9950 JP 2000-86883 A

  However, although the deodorizing component disclosed in Patent Document 1 shows a deodorizing effect on methyl mercapton, hydrogen sulfide and ammonia, it does not show a deodorizing effect on aldehydes. In addition, the sodium tetrahydroborate disclosed in Patent Document 2 may not exhibit a sufficient aldehyde reduction effect depending on the amount added, and a more reliable VOC countermeasure is required.

  This invention is made | formed in view of the above point, and it aims at providing the polyurethane foam molded object with which generation | occurrence | production of aldehydes was reduced as a countermeasure against VOC, and a sheet pad.

  The present inventor has intensively studied to reduce aldehydes generated from a polyurethane foam molded product for VOC countermeasures. By adding thiosulfate to a polyurethane foam raw material, the aldehyde reduction is superior to the conventional one. It has been found that an effect can be obtained, and the present invention has been completed.

  That is, the polyurethane foam molded body according to the present invention is obtained by foam-molding a polyurethane foam raw material containing a thiosulfate. Moreover, the pad for sheet | seats concerning this invention consists of a polyurethane foam molded object formed by foam-molding the polyurethane foam raw material containing a thiosulfate.

  According to the present invention, since aldehydes such as acetaldehyde and formaldehyde in the polyurethane foam molded product are reduced by thiosulfate, generation of such aldehydes can be reduced to suppress off-flavors.

In the present invention, the polyurethane foam raw material is foam-molded by containing thiosulfate. As such a thiosulfate, alkali metal salts such as potassium salt and sodium salt are preferably used, and sodium salt (Na ₂ S ₂ O ₃ ) is particularly preferably used. The amount of thiosulfate added to the polyurethane foam raw material is not particularly limited, but is preferably 10 to 100 ppm by weight, more preferably 20 to 50 ppm.

  As the polyurethane foam raw material, since it varies depending on the use of the polyurethane foam molded article, it cannot generally be said, but usually, polyols such as polyether polyol, isocyanates such as organic polyisocyanate, further, catalyst, foaming agent, It contains a foam stabilizer. The polyurethane foam molded body of the present invention may be any of soft, semi-rigid and rigid foam.

  In the case of an automobile seat pad, the polyurethane foam molded body is made of a flexible foam. As the polyols, a polyfunctional alcohol compound such as ethylene glycol or glycerin is used as an initiator, and ethylene oxide or propylene oxide is used. A polyoxyalkylene polyol having an alkylene oxide added thereto is preferably used. In addition to the polyoxyalkylene polyol, it is preferable to use a polymer polyol in which polymer particles are dispersed in the form of fine particles in a polyol compound, and the polymer particles include homopolymers or copolymers of vinyl monomers such as acrylonitrile and styrene. And particles of condensation polymerization polymers such as polyester and polyurea.

  Moreover, as the isocyanates, tolylene diisocyanate and diphenylmethane diisocyanate are preferably used. Furthermore, water is preferably used as the foaming agent, and the amount used is usually 0.1 to 8 parts by weight per 100 parts by weight of polyols. As the catalyst, amine-based catalysts such as triethylenediamine and bis (N, N-dimethylamino-2-ethyl) ether are preferably used, and the amount used is usually 0.05 to 100 parts by weight with respect to 100 parts by weight of the polyol compound. 10 parts by weight. Furthermore, as the foam stabilizer, various silicone foam stabilizers such as dimethylsiloxane and polyether dimethylsiloxane are preferably used, and the amount used is usually 0.01 to 5 weights with respect to 100 parts by weight of the polyol compound. Part. In addition, various additives such as a crosslinking agent, an emulsifier, an antioxidant, an ultraviolet absorber, an anti-aging agent, a filler, a flame retardant, and a plasticizer can be added as necessary.

  As a method for producing a polyurethane foam molded article, a known method can be adopted, and any one of a one-shot method and a prepolymer method can be applied, but the one-shot method is preferable. Moreover, it does not specifically limit as a shaping | molding method, All are applicable, such as block shaping | molding which shape | molds a plate-shaped slab, and mold shaping | molding which shape | molds using a shaping | molding die.

  In the case of a pad for a sheet, a thiosulfate is added and mixed in a polyol component to a polyurethane foam raw material, this is mixed with an isocyanate component, and the mixed polyurethane foam raw material is injected into a foam mold, A method of manufacturing by foam molding in a cavity is common.

  Examples of the present invention are shown below, but the present invention is not limited to these Examples.

(Example 1)
30 ppm of sodium thiosulfate (Na ₂ S ₂ O ₃ ) is added to the polyurethane foam raw material (HR formulation) shown in Table 1 below, and foam molding is performed using a prototype mold having a cavity space of 400 × 400 × 100 mm. Thus, a polyurethane foam molded body of Example 1 was obtained. At that time, sodium thiosulfate was added to and mixed with the polyol component, and this was mixed with the isocyanate component and then injected into the mold.

As Comparative Example 1, in place of the above sodium thiosulfate, 30 ppm of sodium tetrahydroborate (NaBH ₄ ) was added, and the others were similarly used to obtain a polyurethane foam molded article. As a control, a polyurethane foam molded article obtained by foam molding without adding these reducing agents was obtained.

About each obtained polyurethane foam molded object, the generation amount of formaldehyde and acetaldehyde was measured. In the measurement, a rectangular parallelepiped test piece having a surface of 100 mm in length and 80 mm in width and a thickness of 70 mm was cut out from each of the above-mentioned molded bodies, and the sample was enclosed in a sampling bag. Heated for hours, collected volatile components in a special collection tube (“DNPH cartridge” manufactured by Waters), and analyzed by high performance liquid chromatography (manufactured by Shimadzu Corporation) to measure the amount of aldehyde gas emitted. . The results are shown in Table 2.

As shown in Table 2, the aldehyde was clearly reduced when Na ₂ S ₂ O _{3 according} to the present invention was added, compared to when NaBH ₄ was added.

(Example 2)
30 ppm of sodium thiosulfate (Na ₂ S ₂ O ₃ ) is added to the polyurethane foam raw material (HOT formulation) shown in Table 3 below, and foam molding is performed using a prototype mold having a cavity space of 400 × 400 × 100 mm. Thus, a polyurethane foam molded body of Example 2 was obtained. At that time, sodium thiosulfate was added to and mixed with the polyol component, and this was mixed with the isocyanate component and then injected into the mold.

As Comparative Example 2, 30 ppm of sodium tetrahydroborate (NaBH ₄ ) was added in place of the sodium thiosulfate, and a polyurethane foam molded article was obtained in the same manner. As a control, a polyurethane foam molded article obtained by foam molding without adding these reducing agents was obtained.

About each obtained polyurethane foam molded object, it carried out similarly to the said Example 1, and measured the generation amount of formaldehyde and acetaldehyde. The results are shown in Table 4.

As shown in Table 4, the aldehyde was clearly reduced when Na ₂ S ₂ O _{3 according} to the present invention was added, compared to when NaBH ₄ was added.

  The present invention can be used for various polyurethane foam molded articles such as automobile seat pads.

Claims (2)

  A polyurethane foam molded article obtained by foam-molding a polyurethane foam raw material containing thiosulfate.   A pad for a sheet comprising a polyurethane foam molded article obtained by foam-molding a polyurethane foam raw material containing thiosulfate.