JP2014019832A - Method for reducing volatile organic compounds and method for producing polyurethane foam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for reducing volatile organic compounds and a method for producing a polyurethane foam, which are capable of effectively reducing volatile organic compounds including toluene in a polyurethane foam.SOLUTION: The reduction method and the production method include: a heating step of heating an open-cell polyurethane foam into a heated polyurethane foam; and a volatilization step of volatilizing volatile organic compounds, which are contained in the heated polyurethane foam and include toluene, by placing the heated polyurethane foam under a reduced-pressure environment.

Description

  The present invention relates to a method for reducing volatile organic compounds and a method for producing polyurethane foam. More specifically, the present invention relates to a method for reducing volatile organic compounds that can effectively reduce volatile compounds contained in polyurethane foam and a method for producing polyurethane foam.

  In recent years, interest in volatile organic compounds (hereinafter simply referred to as “VOC”) released during use of various products has increased, and various attempts have been made to reduce this. As a method for reducing VOC contained in a polyurethane foam, the following Patent Document 1 and the following Patent Document 2 are known. In addition, the following patent document 3 and the following patent document 4 are known regarding the crushing of a self-foaming polyurethane foam.

JP 2006-054443 A JP 2010-137517 A JP 10-04249 A Japanese Patent Laid-Open No. 11-347269

  An object of this invention is to provide the reduction method of a volatile organic compound which can reduce the volatile organic compound in a polyurethane foam effectively, and the manufacturing method of a polyurethane foam.

  The inventor of the present invention has been particularly studying VOC in a vehicle, and has found that there is a conventionally known release of toluene in addition to various VOCs that have been known to be discharged. Further, it has been found that the generation source is polyurethane foam which is frequently used as an interior material. However, it has long been unclear what causes the polyurethane foam to release toluene and when it is released.

  In general, polyurethane foam is formed by foaming upon reaction of a polyol compound and a polyisocyanate compound. Among these, toluene diisocyanate (hereinafter also simply referred to as “TDI”) used as a polyisocyanate compound is a component synthesized from toluene as a raw material. For this reason, there was a concern that toluene may remain, which may be a source of generation. However, according to the inventor's investigation, there is almost no residue of toluene, and what is the source of toluene in a polyurethane foam product? I found out that it was not.

  On the other hand, it has been found that toluene may be detected from various additives other than polyol compounds and polyisocyanate compounds used as raw materials for polyurethane foam. The reason is that even if toluene is not used as a raw material, toluene is used as a solvent or the like for washing a plant for producing various additives, and the toluene may remain and be contained in the additive It turns out that there is sex. It was found that this toluene was not necessarily included, some manufacturers were included, some were not included, and some were included and some were not included.

  Furthermore, when toluene was contained in the polyurethane foam, it was found that it took a very long time to measure the time until toluene was not released from the polyurethane foam. On the other hand, when the polyurethane foam was observed under magnification, it was found that almost no closed cells were observed, and the inside was constituted by open cells. From this, the present inventor thinks that natural gas exchange should be performed in the open-cell polyurethane foam, but there is a factor that toluene is likely to remain inside the foam, and it takes time for emission decay. It was. Therefore, the reduction of volatile organic compounds containing toluene remaining in the polyurethane foam was investigated.

Conventionally, formaldehyde and acetaldehyde, which are well known as VOCs, have polarity, and thus have been easily removed and supplemented using this property (that is, formaldehyde and acetaldehyde are chemically reactive). Is relatively high). However, toluene and the like are stable compounds having no polarity and poor reactivity at room temperature (that is, toluene and the like have low chemical reactivity). For this reason, trapping using an acid / alkali reaction or trapping using an electric charge cannot be performed, and even if physical adsorption by activated carbon is performed, re-release (desorption) due to temperature rise occurs and effective. It turned out that it was not captured. In addition, since the boiling point is relatively high, it could not be sufficiently reduced by low temperature heating considering the influence on the product.
After repeating such various studies, the present inventor has completed the following invention.

That is, in order to solve the above-mentioned problems, the method for reducing the volatile organic compound of the polyurethane foam according to claim 1 comprises a heating step of heating the open-cell polyurethane foam to form a heated polyurethane foam,
And a volatilizing step of volatilizing a volatile organic compound containing toluene contained in the heated polyurethane foam by placing the heated polyurethane foam in a reduced pressure environment.

  The gist of the method for reducing the volatile organic compound of the polyurethane foam according to claim 2 is that, in claim 1, the open-cell polyurethane foam is obtained using a silicone foam stabilizer.

The method for producing a polyurethane foam according to claim 3 is a heating step in which a foamed polyurethane foam is heated to form a heated polyurethane foam.
And a volatilizing step of volatilizing a volatile organic compound containing toluene contained in the heated polyurethane foam by placing the heated polyurethane foam in a reduced pressure environment.

  According to a fourth aspect of the present invention, there is provided a polyurethane foam manufacturing method according to the third aspect, wherein the open-cell polyurethane foam is obtained using a silicone-based foam stabilizer.

According to the method for reducing the volatile organic compound of the polyurethane foam of the present invention, the volatile organic compound containing toluene can be effectively reduced from within the polyurethane foam.
Furthermore, when the open-cell polyurethane foam is obtained using a silicone-based foam stabilizer, volatile organic compounds containing toluene can be reduced particularly effectively.

According to the method for producing a polyurethane foam of the present invention, volatile organic compounds containing toluene can be effectively reduced from within the polyurethane foam.
Furthermore, when a continuous foam polyurethane foam is obtained using a silicone-based foam stabilizer, volatile organic compounds containing toluene can be reduced particularly effectively.

The present invention will be further described in the following detailed description with reference to the drawings referred to, with reference to non-limiting examples of exemplary embodiments according to the present invention. Similar parts are shown through several figures.
It is a graph which shows the change of the discharge | release amount of toluene.

  The items shown here are exemplary and illustrative of the embodiments of the present invention, and are the most effective and easy-to-understand explanations of the principles and conceptual features of the present invention. It is stated for the purpose of providing what seems to be. In this respect, it is not intended to illustrate the structural details of the present invention beyond what is necessary for a fundamental understanding of the present invention. It will be clear to those skilled in the art how it is actually implemented.

The method for reducing the volatile organic compound of the polyurethane foam according to the present invention includes a heating step and a volatilization step.
Moreover, the manufacturing method of the polyurethane foam of this invention makes it a summary to provide a heating process and a volatilization process.

The “heating step” is a step of heating a foamed polyurethane foam to form a heated polyurethane foam.
The foamed polyurethane foam may be obtained in any way. For example, a composition containing a polyol compound, a polyisocyanate compound and the like is foamed together with resination to form a closed cell polyurethane foam, and then a foamed polyurethane foam obtained through foam breaking treatment. May be. The composition containing a polyol compound, a polyisocyanate compound, and the like may be an open-cell polyurethane foam obtained by being resinized while expanding by foaming and simultaneously generating bubbles.
In the present invention, a polyurethane foam having an open cell ratio (based on ASTM D2856-70) of 50% or more is referred to as an open-cell polyurethane foam.

The heating may be performed in any form. That is, for example, it may be put into a batch type heating furnace and heated, or it may be passed through a line type heating furnace and heated, and various other heating means can be used. These heating forms may use only 1 type and may use 2 or more types together.
Further, the heating means is not particularly limited, and means for heating by applying hot air (hot air heating means) may be used, means for heating by infrared irradiation (infrared heating means) may be used, and various other types. Any heating means can be used. These heating means may use only 1 type and may use 2 or more types together.

Although the heating temperature in a heating process is not specifically limited, Usually, it heats to 70 degreeC or more. The heating temperature is preferably 75 ° C. or higher, more preferably 80 ° C. or higher, still more preferably 90 ° C. or higher, and particularly preferably 100 ° C. or higher. Although the upper limit of the heating temperature is not particularly limited, it is preferable that the physical properties of the resulting polyurethane foam are not greatly affected. Usually, it is 130 ° C or lower, preferably 125 ° C or lower, more preferably 120 ° C or lower, and further 115 ° C or lower. Preferably, 110 degrees C or less is especially preferable.
The heating temperature is a temperature measured by inserting a thermocouple to the center of the polyurethane foam to be measured (measured using a thermocouple thermometer).

The “volatilization step” is a step of volatilizing a volatile organic compound containing toluene contained in the heated polyurethane foam by placing the heated polyurethane foam in a reduced pressure environment.
That is, the boiling point of VOC containing toluene contained in the heated polyurethane foam is lowered in a reduced pressure environment. When the lowered boiling point falls below the temperature of the heated polyurethane foam, the component is volatilized. For this reason, normally, the said heating process is a process of heating a polyurethane foam to temperature higher than the boiling point of toluene fall | descended by pressure reduction in a volatilization process. Conversely, the volatilization step is a step of lowering the boiling point of toluene by reducing the pressure so that the boiling point of toluene is lower than the temperature of the polyurethane foam heated in the heating step.

  For example, the boiling point of toluene at normal pressure (about 101.3 kPa) is about 111 ° C. In contrast, the boiling point at 30 kPa is lowered to about 70 ° C., the boiling point at 10 kPa is lowered to about 50 ° C., and in particular the boiling point at 4 kPa is lowered to about 30 ° C. Thus, the VOC containing toluene has a boiling point lower than the standard boiling point due to reduced pressure for each component. On the other hand, polyurethane foam is preheated in the heating process. For example, toluene contained in a heated polyurethane foam heated to 70 ° C. or more volatilizes in the heated polyurethane foam and is easily discharged outside the foam if the boiling point after decompression becomes 70 ° C. or less due to boiling point drop. Become.

Actually, as the pressure decreases, the temperature of the heated polyurethane foam itself decreases due to the vaporization of moisture contained in the foam. For this reason, the situation where the boiling point of the VOC containing toluene exceeds the temperature in the heated polyurethane foam may be obtained only for a short time. During that short time, the VOC containing toluene is very effectively heated to the polyurethane. It was found that it can be taken out from the foam.
For this reason, in general, in the heating step, as described above, the heated polyurethane foam is preferably heated to 70 ° C. or higher, and in the volatilization step, the pressure is preferably reduced to 30 kPa or lower. This reduced pressure is further preferably 20 kPa or less, more preferably 10 kPa or less, still more preferably 5 kPa or less, and particularly preferably 4 kPa or less. Although the pressure can be reduced to any extent, the lower limit of pressure reduction is about 0.5 kPa from the viewpoint of securing the appearance quality of the polyurethane foam by the reduced pressure and the degree of air escape from the polyurethane foam, and 1 kPa or more. Preferably, 2 kPa or more is preferable, and 3 kPa or more is preferable.

The decompression method in the volatilization step is not particularly limited. For example, the heated polyurethane foam is accommodated in a pressure-resistant container (a container that maintains the internal volume even when the pressure is reduced), and the inside of the pressure-resistant container is decompressed. It can be placed under a reduced pressure environment.
As such an apparatus, a crushing apparatus capable of defoaming a polyurethane foam having closed cells can be used. Further, the pressure reduction may be performed once until a desired value, but it can be performed gradually in steps, and it is particularly preferable to perform the pressure reduction divided into a plurality of times. For example, when the pressure is reduced from 100 kPa to 25 kPa, the pressure is preferably reduced stepwise by dividing into 2 to 5 times, and more preferably stepwise reduced by dividing into 2 to 4 times.

  Furthermore, in the volatilization step, the polyurethane foam under reduced pressure can be heated as necessary. Since the temperature of the polyurethane foam under reduced pressure decreases due to the reduced pressure, as described above, it is difficult to maintain the temperature of the polyurethane foam so as to exceed the boiling point of toluene or the like lowered by the reduced pressure. For this reason, by heating also in a volatilization process, it becomes possible to maintain the temperature of a polyurethane foam so that it exceeds the boiling point of toluene etc. which were dropped by pressure reduction, or to lengthen the time to maintain.

  The method for heating the polyurethane foam under reduced pressure is not particularly limited, but it is particularly preferable to perform microwave heating. The polyurethane foam under reduced pressure is placed in a substantially heat-insulated state in the pressure vessel. For this reason, it is difficult to conduct heat from an external heat source. On the other hand, if it is microwave heating, the polyurethane foam in a pressure-resistant container can be heated directly.

  The polyurethane foam used in the present invention is usually a flexible polyurethane foam. As a raw material for the flexible polyurethane foam, a polyol compound and a polyisocyanate compound are required, and a catalyst, a foaming agent, a foam stabilizer and the like can be usually used.

  The polyol compound is a compound having at least two hydroxyl groups in the molecule. Examples of the polyol compound include polyether polyols, polyester polyols, alkylene glycols, and polymer polyols using polyether polyols or polyester polyols. These may use only 1 type and may use 2 or more types together.

  Polyether polyols include ethylene glycol, diethylene glycol, propylene glycol, 1,3-butanediol, dipropylene glycol, neopentyl glycol, 1,4-hexanediol, 1,5-hexanediol, glycerin, pentaerythritol, sorbitol. And polyether polyols in which alkylene oxides such as ethylene oxide and propylene oxide are added to polyhydric alcohols such as trimethylolpropane, cyclohexanediol, and cyclohexanedimethanol. These may use only 1 type and may use 2 or more types together.

  Examples of the polyester polyol include a polyester polyol compound obtained by polycondensation of an aliphatic carboxylic acid and / or an aromatic carboxylic acid and a polyhydric alcohol. Examples of the aliphatic carboxylic acid include malonic acid, succinic acid, and adipic acid, and examples of the aromatic carboxylic acid include phthalic acid. Further, as the polyhydric alcohol, the above polyhydric alcohol that can constitute the above-described polyether polyol can be applied as it is. These may use only 1 type and may use 2 or more types together.

  Examples of the alkylene glycol include ethylene glycol, diethylene glycol, propylene glycol, 1,3-butanediol, dipropylene glycol, neopentyl glycol, 1,4-hexanediol, 1,5-hexanediol, glycerin, pentaerythritol, sorbitol, triglyceride. Examples include polyhydric alcohols such as methylolpropane, cyclohexanediol, and cyclohexanedimethanol. These may use only 1 type and may use 2 or more types together.

The polyisocyanate compound is a compound having at least two isocyanate groups in the molecule. Examples of the polyisocyanate compound include aliphatic polyisocyanates, aromatic polyisocyanates, and modified compounds thereof. These may use only 1 type and may use 2 or more types together.
Although the compounding quantity of a polyisocyanate compound is not specifically limited, It is 10-60 mass parts normally with respect to 100 mass parts of the whole polyol compound.

Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, isophorone diisocyanate, and dicyclohexamethane diisocyanate. These may use only 1 type and may use 2 or more types together.
Examples of the aromatic polyisocyanate include toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthalene diisocyanate, xylylene diisocyanate, and polymeric polyisocyanate (crude MDI). These may use only 1 type and may use 2 or more types together.
Examples of the modified polyisocyanate compound include a carbodiimide-modified compound of aliphatic polyisocyanate or aromatic polyisocyanate. These may use only 1 type and may use 2 or more types together.

Examples of the catalyst include amines (amine compounds) and organometallic compounds. These may use only 1 type and may use 2 or more types together.
Examples of amines include monoamines, diamines, triamines, polyamines, cyclic amines, alcohol amines, ether amines and the like. These may use only 1 type and may use 2 or more types together.
Examples of organometallic compounds include organotin compounds, organomercury compounds, and organolead compounds. These may use only 1 type and may use 2 or more types together.
Although the compounding quantity of a catalyst is not specifically limited, When using amines, it is 0.01-2 mass parts normally with respect to 100 mass parts of the whole polyol compound. When using an organometallic compound, it is 0.01-1 mass part normally with respect to 100 mass parts of the whole polyol compound.

Examples of the foaming agent include water, hydrocarbons (such as pentane), liquefied carbon dioxide gas, and alkylene chlorides (such as methylene chloride and ethylene chloride). These may use only 1 type and may use 2 or more types together.
Although the compounding quantity of a foaming agent is not specifically limited, When using water, it is 0.5-7 mass parts normally with respect to 100 mass parts of the whole polyol compound.

Various surfactants can be appropriately used as the foam stabilizer. That is, for example, soap surfactants (soap foam stabilizers) such as fatty acid salts, sulfonate surfactants (sulfonate foam stabilizers) such as alkylbenzene sulfonates and alkyl ether sulfonates, Higher alcohol surfactants (higher alcohol foam stabilizers) such as lauryl sulfate, amino acid surfactants (amino acid foam stabilizers), silicone surfactants (silicone foam stabilizers), fluorine compound interfaces Examples include activators (fluorine compound-based foam stabilizers). These may use only 1 type and may use 2 or more types together.
In addition, any surfactant such as a cationic surfactant, an anionic surfactant, and a nonionic surfactant can be used. These may use only 1 type and may use 2 or more types together.
Although the compounding quantity of a foam stabilizer is not specifically limited, Usually, it is 0.001-5 mass parts with respect to 100 mass parts of the whole polyol compound.

Among the above foam stabilizers, the method of the present invention can exert its action particularly effectively when a silicone foam stabilizer is used as the foam stabilizer.
A silicone-based foam stabilizer is a compound having a polysiloxane chain as a skeleton. Further, it may be a polyether-modified compound, a polyether-polysiloxane block polymer (block structure of a polysiloxane chain and a polyoxyalkylene chain), or other modified and structured compounds. May be. These may use only 1 type and may use 2 or more types together.
Of these, the polyether-modified silicone foam stabilizer usually has a polysiloxane chain and a polyoxyalkylene chain, and has a structure in which the polyoxyalkylene chain is modified in the main polysiloxane chain. Can do. The modification form is not particularly limited, and examples thereof include one-end modification, both-end modification, and graft modification. These may use only 1 type and may use 2 or more types together.

  The polysiloxane chain is usually an organopolysiloxane chain having an organic group in the side chain, and examples thereof include a polydimethylsiloxane chain. The polyoxyalkylene chain includes a polyoxyalkylene chain composed of one kind of oxyalkylene group such as a polyoxyethylene chain and a polyoxypropylene chain, an oxyethyleneoxypropylene block chain, and an oxyethyleneoxypropylene random chain. Examples thereof include polyoxyalkylene chains composed of two or more oxyalkylene groups such as chains. These may use only 1 type and may use 2 or more types together.

  Among these, for example, in a silicone-based foam stabilizer having a polydimethylsiloxane chain as a main chain and a polyoxyalkylene chain as a side chain, the polyoxyalkylene chain has an oxyethylene group (E) and an oxypropylene group. It is preferable that it contains both (P). The number of dimethylsiloxane units in the polydimethylsiloxane chain in such a silicone-based foam stabilizer may be 10 to 200. Moreover, the molar ratio (E / P) of the oxyethylene group (E) and the oxypropylene group (P) can be 3 to 9. Furthermore, the average molecular weight of the polyoxyalkylene chain can be 500-2000.

  In addition to the polyol compound, polyisocyanate compound, catalyst, foaming agent, and foam stabilizer, the polyurethane foam used in the present invention contains an antioxidant, an ultraviolet absorber, a flame retardant, a filler, a colorant, and the like. It can be used as appropriate.

  The shape, size, etc. of the polyurethane foam obtained by the polyurethane foam production method of the present invention are not particularly limited, and its use is not particularly limited. For example, the polyurethane foam is used as an interior material for automobiles, railway vehicles, ships, airplanes, and the like. Among these, automobile interior materials include automotive interior materials. Specifically, a seat pad, a headrest pad, an armrest pad material, an armrest pad for a door trim, and the like can be given.

Hereinafter, the present invention will be described more specifically with reference to examples.
(1) Comparative Example 1
The amount of toluene released was measured using the open-cell polyurethane foam in which toluene release was observed without using the heating step and the volatilization step described above.
That is, the seat pad for a rear seat of the vehicle (product life size, weight about 3500 g, a volume of about 0.06 m ³⁾ was placed in a sealed container of volume 1 m ³ of gas of pure nitrogen gas (water in the container and other Gas). Thereafter, the sealed container was left in a heating furnace at 40 ° C. (under atmospheric pressure) for 2 hours.

Next, in accordance with JIS A1966 specified in JASO Standard “JASO M 902 Automotive Parts-Interior Materials-Volatile Organic Compound (VOC) Emission Measurement Method” by the Japan Society for Automotive Engineers, The toluene concentration was measured. As a result, the amount of toluene released was 47.965 (μg / piece).
In this polyurethane foam, a silicone-based foam stabilizer is used as a foam stabilizer.

(2) Example 1
The same open cell polyurethane foam as used in Comparative Example 1 was left in a heating furnace at a temperature of 80 ° C. for 1 hour to obtain a heated polyurethane foam at a temperature of 80 ° C. Next, the heated polyurethane foam is put into a vacuum crushing apparatus, and the pressure is reduced by dividing it into three steps up to 4 kPa to remove and reduce the volatile organic compound, thereby obtaining the polyurethane foam of Example 1. It was.
With respect to the obtained polyurethane foam of Example 1, the amount of toluene released was measured in the same manner as in Comparative Example 1. That is, after putting the polyurethane foam of Example 1 into a sealed container having a volume of 1 m ³ , the gas in the container is replaced with pure nitrogen gas (not containing moisture and other gases), and then the sealed container is placed at 40 ° C. ( It was left in a heating furnace under atmospheric pressure for 2 hours. Next, in accordance with JIS A1966, the toluene concentration in the sealed container after being left for 2 hours was measured. As a result, the amount of toluene released was 22.357 (μg / piece).

(3) Example 2
The same open cell polyurethane foam as used in Comparative Example 1 was left in a heating furnace at a temperature of 90 ° C. for 1 hour to obtain a heated polyurethane foam at a temperature of 90 ° C. Subsequently, the heated polyurethane foam was put into the vacuum crushing apparatus, and the pressure was reduced by dividing the process into three steps up to 4 kPa to remove and reduce the volatile organic compounds.
The polyurethane foam of Example 2 obtained in this way was subjected to the same measurement as in Comparative Example 1, and the amount of toluene released was measured. As a result, the amount of toluene released was 21.315 (μg / piece).

(4) Example 3
The same open cell polyurethane foam as used in Comparative Example 1 was left in a heating furnace at a temperature of 100 ° C. for 1 hour to obtain a heated polyurethane foam at a temperature of 100 ° C. Subsequently, the heated polyurethane foam was put into the vacuum crushing apparatus, and the pressure was reduced by dividing the process into three steps up to 4 kPa to remove and reduce the volatile organic compounds.
The polyurethane foam of Example 3 thus obtained was subjected to the same measurement as in Comparative Example 1, and the amount of toluene released was measured. As a result, the released amount of toluene was 17.864 (μg / piece).

(5) Effect of Example The results of the above (1) to (4) are shown as a graph in FIG. From this result, the polyurethane foams of Examples 1 to 3 in which this reduction method was applied to the polyurethane foam of Comparative Example 1 that was not subjected to the reduction method of volatile organic compounds in the polyurethane foam of the present invention was extremely effective. It can be seen that the amount of toluene released was reduced. That is, the amount of toluene released in Examples 1 to 3 was 37.2 to 46.6% of Comparative Example 1 and was reduced to less than half.

Furthermore, the ethylbenzene measured in the same manner was 31.913 (μg / piece) in Comparative Example 1, whereas it was 10.077 to 12.760 (μg / piece) in Examples 1 to 3. Remarkably reduced. That is, the amount of ethylbenzene released was reduced to less than half, 37.2 to 46.6%.
In addition, xylene was 47.094 (μg / piece) in Comparative Example 1, but was significantly reduced to 12.676 to 16.237 (μg / piece) in Examples 1 to 3. That is, the amount of xylene released was reduced to 26.9-34.5% to less than half.
Further, styrene was 27.000 (μg / piece) in Comparative Example 1, whereas in Examples 1 to 3, it was significantly reduced to 4.138 to 6.393 (μg / piece). That is, the amount of styrene released was 15.3 to 23.7%, which was reduced to less than a quarter.
From the above, the method for reducing the volatile organic compound of the polyurethane foam and the method for producing the polyurethane foam according to the present invention is a compound having a high boiling point as a volatile organic compound. It can be seen that it works very effectively even on difficult and stable compounds.

  The foregoing examples are for illustrative purposes only and are not to be construed as limiting the invention. Although the invention has been described with reference to exemplary embodiments, it is to be understood that the language used in the description and illustration of the invention is illustrative and exemplary rather than limiting. As detailed herein, changes may be made in its form within the scope of the appended claims without departing from the scope or spirit of the invention. Although specific structures, materials and examples have been referred to in the detailed description of the invention herein, it is not intended to limit the invention to the disclosure herein, but rather, the invention is claimed. It covers all functionally equivalent structures, methods and uses within the scope.

Claims (4)

Heating the open-cell polyurethane foam into a heated polyurethane foam;
A volatilizing step for volatilizing a volatile organic compound containing toluene contained in the heated polyurethane foam by placing the heated polyurethane foam in a reduced pressure environment, Reduction method.   The method for reducing volatile organic compounds in a polyurethane foam according to claim 1, wherein the open-cell polyurethane foam is obtained using a silicone foam stabilizer. Heating the open-cell polyurethane foam into a heated polyurethane foam;
And a volatilizing step for volatilizing a volatile organic compound containing toluene contained in the heated polyurethane foam by placing the heated polyurethane foam in a reduced pressure environment.   The method for producing a polyurethane foam according to claim 3, wherein the open-cell polyurethane foam is obtained using a silicone-based foam stabilizer.

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