JPH09249729A - Method for producing flexible polyurethane foam - Google Patents

Abstract

(57) 【Abstract】 PROBLEM TO BE SOLVED: To provide a flexible polyurethane foam excellent in low fogging property, high heat fusion property and flame retardancy. SOLUTION: A mixture of a urethane-modified polyether polyol, a high-molecular weight piperazine-based polyol obtained by ring-opening addition polymerization of an alkylene oxide to a piperazine and a condensation-based resin fine particle-dispersed polyol, and a polyisocyanate in the presence of a small amount of an amine catalyst A lower reaction is performed to produce a flexible urethane foam.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a flexible polyurethane foam excellent in flame retardancy and heat fusion property.

[0002]

2. Description of the Related Art Conventionally, a flexible polyurethane foam obtained from a polyether polyol has excellent properties such as impact resilience, compression set and hardness. But,
The heat fusion property in heat welding, flame welding, high frequency welding, etc. is far inferior to polyurethane foam obtained from polyester polyol.

Heat-fusible flexible polyurethane foams have heretofore been produced using polyether polyols obtained by modifying ordinary polyether polyols or specific additives in order to improve heat-fusability. For example, it is known to use a modified polyether polyol obtained by ester-modifying the end of a polyether polyol. Further, it is known that a polyurethane foam excellent in heat fusion property can be obtained by using it together with a phosphorus compound. Further, in the case of obtaining a flame-retardant heat-fusible polyurethane foam, it was considered that the addition of an organohalogen phosphate ester compound was essential.

On the other hand, in order to produce a flexible polyurethane foam, it is essential to add a certain amount or more of an amine catalyst.

However, in recent years, the problem of fog on the surface of automobile glass caused by the amine catalyst and the organohalogen phosphate compound has come to be highlighted.

[0006] For the purpose of preventing fogging, amine-based catalyst systems are those in which a part of the structure of the amine-based catalyst is hydroxylated or aminated so as to react with isocyanate (hereinafter referred to as reactive amine-based catalyst). It became so. In addition, in the addition of an organic halogen-based phosphoric acid ester compound, an oligomer-type organic halogen-based phosphoric acid ester compound having a molecular weight increased from a low molecular weight type (monomer type) has come to be used.

[0007]

However, since the reactive amine-based catalyst reacts with isocyanate during the reaction,
The catalytic activity in the latter half of the reaction becomes low and the curing becomes insufficient.
Further, in order to perform sufficient curing, it is necessary to increase the amount of the reactive amine-based catalyst added, which causes a problem of fogging due to the amine-based catalyst regenerated by thermal decomposition.

In the case of a flame-retardant heat-fusible polyurethane foam, a large amount of an oligomer type organohalogen phosphate compound is used in order to maintain flame retardancy. It was a problem that it had an adverse effect.

The present invention is a method for producing a flexible polyurethane foam having excellent flame retardancy and heat-sealing property, and by reducing the use amount of an amine-based catalyst or an organic halogen-based phosphate compound, low fogging property is improved. And,
It is an object of the present invention to produce a flame-retardant flexible polyurethane foam having excellent flame-retardant property and heat-sealing property.

[0010]

The present invention is the following invention which solves the above-mentioned problems.

A high-molecular weight active hydrogen compound having two or more active hydrogen-containing groups capable of reacting with an isocyanate group and a polyisocyanate compound are reacted in the presence of a foaming agent, a foam stabilizer, a catalyst and other auxiliaries to give a flexible polyurethane foam. In the production of (1), a mixture of the following polyol (A), polyol (B) and polyol (C) is used as at least a part of the high molecular weight active hydrogen compound, and (2) is an amine catalyst not used? Or a method for producing a flexible polyurethane foam having excellent flame retardancy and heat fusion properties, which comprises using an amine-based catalyst in an amount of less than 0.35% by weight based on the total polyol.

A high-molecular weight active hydrogen compound having two or more active hydrogen-containing groups capable of reacting with an isocyanate group and a polyisocyanate compound are reacted in the presence of a foaming agent, a foam stabilizer, a catalyst and other auxiliaries to give a flexible polyurethane foam. In the production of (1), a mixture of the following polyol (A) and polyol (B) is used as at least a part of the high molecular weight active hydrogen compound, (2) a flame retardant is used as an auxiliary agent, and (3) ) Amine-based catalysts No amine-based catalysts or 0.3 based on total polyol
A method for producing a flexible polyurethane foam having excellent flame retardancy and heat fusion characteristics, which comprises using an amine-based catalyst in an amount of less than 5% by weight.

Polyol (A): A high-molecular-weight piperazine-based polyol obtained by ring-opening addition polymerization of alkylene oxide to piperazines. Polyol (B): A modified polyether polyol selected from urethane modified polyether polyol and ester modified polyether polyol. Polyol (C): Fine particle-dispersed polyol having fine particles of aldehyde condensation resin as a dispersoid.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

(Polyol (A)) The polyol (A) used in the present invention is a high molecular weight piperazine-based polyol obtained by subjecting piperazines to an alkylene oxide ring-opening addition reaction. The piperazine in the present invention means not only piperazine but also substituted piperazine in which a hydrogen atom in piperazine is replaced with an organic group such as an alkyl group or an aminoalkyl group. It is essential that the piperazines have two or more active hydrogens capable of reacting with an alkylene oxide. In a piperazine-based polyol obtained by subjecting an alkylene oxide to a ring-opening addition reaction using such a compound as an initiator, the two nitrogen atoms constituting the ring in the piperazine are tertiary amines.

Among the piperazines, a substituted piperazine is preferable, and a substituted piperazine having 3 or more nitrogen atoms in the molecule, which is obtained by substituting a hydrogen atom with an aminoalkyl group or the like, is particularly preferable. Among the substituted piperazines, N-substituted piperazines are preferable, and N-aminoalkyl piperazines are particularly preferable.

Specific piperazines include piperazine,
2-methylpiperazine, 2-ethylpiperazine, 2-butylpiperazine, 2-hexylpiperazine, 2,5-,
Hydrogen atom bonded to carbon atom constituting ring such as 2,6-, 2,3- or 2,2-dimethylpiperazine, 2,3,5,6- or 2,2,5,5-tetramethylpiperazine And N- (2-aminoethyl) piperazine in which is substituted with a lower alkyl group, N-aminoalkylpiperazine in which a hydrogen atom bonded to a nitrogen atom constituting a ring is substituted with an aminoalkyl group, and the like. Particularly, N- (2-aminoethyl) piperazine is preferable.

The alkylene oxide having a ring-opening addition reaction with piperazines is preferably an alkylene oxide having 2 to 4 carbon atoms. Specifically, at least one selected from ethylene oxide, propylene oxide, 1,2-butylene oxide, and 2,3-butylene oxide is preferable. In particular, the combined use of propylene oxide and ethylene oxide is preferable.

The molecular weight per hydroxyl group of the polyol (A) is preferably 500 to 10,000, particularly preferably 800 to 3,000. The number of hydroxyl groups is preferably 2 to 4.

The polyol (A) preferably contains an oxyethylene group at the terminal or inside, and the content thereof is 3 to.
It is preferably 35% by weight, particularly preferably 5 to 35% by weight. Most of the oxyethylene group is preferably present at the terminal portion of the molecular chain.

The polyol (A) may be a mixture of two or more kinds, and in that case, the preferable average number of hydroxyl groups and the range of average hydroxyl value are as described above.

The amount of these polyols (A) used is preferably 5 to 35% by weight based on the total polyol. If it is less than 5% by weight, the amount of the amine-based catalyst used must be increased, and the effect of low fogging property is lost. 3
If it exceeds 5% by weight, the proportion of the polyol (B) in the total polyol becomes small, resulting in poor heat fusion property.

(Polyol (B)) The polyol (B) used in the present invention is a modified polyether polyol selected from urethane modified polyether polyol and ester modified polyether polyol.

(Polyether polyol) The modified polyether polyol is obtained by modifying the polyether polyol. The polyether polyol before modification is preferably a polyether polyol mainly containing oxypropylene groups and / or oxyethylene groups, which is produced by adding an alkylene oxide to a polyfunctional initiator.

Examples of polyfunctional initiators include polyhydric alcohols, polyhydric phenols, alkanolamines, polyvalent amines, and low molecular weight polyoxyalkylene polyols obtained by adding a small amount of alkylene oxide to these, and there are two types. You may use together the above.

Specifically, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, glycerin, trimethylolpropane, pentaerythritol, diglycerin, methylglycoside, dextrose, sorbitol, sucrose, etc. Polyhydric alcohols, bisphenol A, bisphenol S, polyhydric phenols such as phenol-formaldehyde initial condensation products, alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, diisopropanolamine, ethylenediamine, propylenediamine, diethylenetriamine, diaminotoluene. Addition of a small amount of alkylene oxide to polyvalent amines such as diaminodiphenylmethane and these There are low molecular weight polyoxyalkylene polyol obtained Te.

The alkylene oxide is preferably an alkylene oxide having 2 to 4 carbon atoms such as ethylene oxide, propylene oxide and butylene oxide, but styrene oxide, epichlorohydrin and other monoepoxides can be used together therewith. As the alkylene oxide, propylene oxide alone or a combination of propylene oxide and ethylene oxide is preferable. When two or more kinds of alkylene oxides and other monoepoxides are added, they may be mixed and reacted, or may be separately and sequentially reacted.

These polyether polyols may be used alone or in combination of two or more.

(Urethane-modified polyether polyol)
As the urethane-modified polyether polyol, those obtained by reacting the above polyether polyol with a polyisocyanate compound are preferable.

The polyether polyol used for modification is
A hydroxyl value of 28 to 120 and a hydroxyl group number of 2 to 8 are preferable. The polyether polyol may be a mixture, in which case the hydroxyl value and the number of hydroxyl groups of the mixture may be within this range. The polyether polyol preferably contains a polyether polyol having an aromatic ring.

The ratio of the polyether polyol to the polyisocyanate compound used is preferably such that the isocyanate groups are less than 1 mol per mol of all hydroxyl groups, and more preferably 0.1 to 0.8 mol. It is preferable.

Examples of the polyisocyanate compound include the compounds described below, of which the aromatic polyisocyanate compound is particularly preferable. This urethane-modified polyether polyol may contain unreacted polyether polyol.

The urethane-modified polyether polyol in the present invention is obtained by reacting a mixture of a polyether polyol having a hydroxyl value of 28 to 80 and a polyether polyol having an aromatic ring having a molecular weight of 1000 or less with an aromatic polyisocyanate compound. Particularly preferred.

(Ester-modified polyether polyol)
As the ester-modified polyether polyol, those obtained by reacting a polyether polyol with a polycarboxylic acid or its derivative or a cyclic ester, and then reacting with an alkylene oxide or a polyhydric alcohol are preferable.

As the polycarboxylic acid, dicarboxylic acids are preferable, and among them, aromatic dicarboxylic acids are particularly preferable.
Examples of the derivative include derivatives such as acid halides, acid anhydrides and esters, and acid anhydrides are preferable. Phthalic anhydride is particularly preferred.

As the polyhydric alcohol, a low molecular weight dihydric or trihydric polyol is preferred, and ethylene glycol, 1,4
Particularly preferred are diols having 8 or less carbon atoms such as butanediol.

The polyether polyol used for modification preferably has a hydroxyl value of 28 to 120 and a hydroxyl number of 2 to 8. In the present invention, the polyether polyol contains 2 to 10
A compound obtained by reacting twice the mole of polycarboxylic acid or its derivative or cyclic ester and then further reacting with 2 to 10 times mole of alkylene oxide is preferable.

Furthermore, a modified polyether polyol which has been both urethane modified and ester modified can be used.
For example, such a modified polyether polyol can be obtained by a method of ester-modifying a urethane-modified polyether polyol or a method of urethane-modifying an ester-modified polyether polyol. Further, such a modified polyether polyol can also be obtained by a method in which a polyether polyol and a polyester polyol are linked via a polyisocyanate.

The polyol (B) also means that it is modified and then diluted with another polyol. As the other polyol, the above-mentioned unmodified polyether polyol is preferable. The amount of the modified polyether polyol in the polyol (B) is 10% by weight or more, especially 30% by weight.
The above is preferred. Usually, the viscosity of the polyol (B) at 25 ° C. is preferably 20,000 cP or less, and particularly preferably 10,000 cP or less. When the viscosity is higher than this, it is preferable to use it by mixing it with another polyol so that the viscosity becomes lower than this value. Further, the polyol (B) may be a mixture of two or more modified polyether polyols.

The polyol (B) in the present invention has 28 to 120 hydroxyl groups, particularly 40 to 80 hydroxyl groups, and preferably 2 to 8 hydroxyl groups, particularly 2.4 to 4.5.

The polyol (B) is preferably 35 to 95% by weight with respect to the total polyol. If it is less than 35% by weight, the heat fusion property is poor, and if it exceeds 95% by weight, the amount of the polyol (A) used is reduced. Therefore, the amount of the amine catalyst used must be increased, and the effect of low fogging property is lost. .

(Polyol (C)) The polyol (C) used in the present invention is a fine particle-dispersed polyol having aldehyde condensation resin fine particles as a dispersoid.

The dispersion medium of the polyol (C) is mainly composed of the above polyether polyol, but a small amount of polyester polyol, polycarbonate polyol, polydiene polyol or polyolefin polyol may be used together. In particular, it is preferable to use the polyether polyol alone or a combination of the polyether polyol and a small amount of the polyester polyol.

The hydroxyl value of the polyether polyol used as the dispersion medium is preferably 20 to 80 mgKOH / g, and particularly preferably 25 to 60 mgKOH / g. The number of hydroxyl groups is preferably 2 to 8, and particularly preferably 2.4 to 4.5.

The polyol (C) in the present invention can be produced by a known method. For example, a method of producing a dispersion of an aldehyde condensation resin by causing a substance capable of forming an aldehyde condensation resin to be condensed in a polyether polyol, forming precipitable particles of the aldehyde condensation resin, And the like.

It can also be produced by adding fine powder of an aldehyde condensation resin to a polyol. The fine powder can be produced by a method of pulverizing an aldehyde condensation resin, a method of precipitating fine particles by condensing a substance capable of forming an aldehyde condensation resin in a dispersion medium other than polyol, and the like.

Preferably, fine particles are deposited by condensing a substance capable of forming an aldehyde condensation type resin in a polyol, or condensation of a substance capable of forming an aldehyde condensation type resin in a dispersion medium other than the polyol. It is produced by a method in which fine particles are deposited by the above-mentioned method and then the dispersion medium is converted into a polyol. By these two methods, it is possible to produce a fine particle-dispersed polyol which has a small particle diameter of fine particles to be produced, is hard to settle in the polyol, and has high dispersion stability.

One of the raw materials for forming the aldehyde condensation resin in the present invention is an aldehyde. As the aldehydes, derivatives of aliphatic, alicyclic, aromatic, heterocyclic aldehyde compounds, other aldehydes, their condensates or compounds capable of generating aldehydes can be used alone or in combination.

Preferred aldehydes are lower aliphatic aldehydes, particularly preferably aliphatic aldehydes having 4 or less carbon atoms and derivatives thereof. Examples thereof include formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, paraformaldehyde, paraacetaldehyde, etc., and formaldehyde is preferable. These aldehydes can also be used by dissolving them in a solvent. A particularly preferred solvent is water, but is not limited to this. The use of an aqueous formaldehyde solution, ie formalin, is particularly preferred in the present invention.

The other raw material for forming the aldehyde condensation resin is a compound which can be condensed with aldehydes to form a solid aldehyde condensation resin (hereinafter referred to as aldehyde condensation compound), which can react with aldehydes. Basically, two positions (hereinafter referred to as reaction sites) are required.

The reaction site is typically a hydrogen-bonded carbon atom in an aromatic group or a hydrogen-bonded nitrogen atom in an amino group or an amide group. The aromatic reaction site is particularly preferably an aromatic ortho position or para position to which a hydroxyl group or an amino group is bonded, and has two or more reaction sites. That is, a compound having no substituent at this site is suitable, and as the compound having an amino group or an amide group, a polyvalent amine compound having two or more of these groups is basically suitable.

Therefore, as the aldehyde condensable compound, aromatic compounds such as phenols and aromatic amines, and urea, melamine, guanidine compounds and other polyvalent amine compounds are preferable. Compounds capable of reacting with these aldehydes can be used in combination of two or more kinds, and with them, a compound having only one reaction site can be used together.

Examples of the phenols among the above aromatic compounds include phenol, cresol, xylenol, p-alkylphenol, p-phenylphenol, bisphenol A, resorcin, and the like, with phenol being particularly preferable.

The aromatic amine includes, for example, aniline, diaminobenzene, p-alkylaniline, N-substituted alkylaniline, diphenylamine, diaminodiphenylmethane, etc., which may be used alone or in combination of two or more in the same manner as phenolic compounds. it can. Since the amino group and amide group of an aromatic amine are themselves reactive sites, they may be regarded as one of the following diamine-based compounds, and the reactivity other than aromatic amine groups and amide groups may be considered. There may be only one part. A particularly preferred aromatic amine is aniline.

The aromatic compounds are not limited to the above compounds, but aromatic hydrocarbons such as benzene and xylene, and other compounds can be used. Further, phenols and aromatic amines may be used in combination, and one or more of them may be combined with other aromatic compounds.

The polyvalent amine compound is preferably a compound basically having two or more amino groups or amide groups, and more preferably a compound having two or more amino groups, such as urea, thiourea and N-substituted urea. Urea, melamine, N
-S-triazines having two or more amino groups represented by melamine compounds such as alkyl-substituted melamine and guanamine compounds such as benzoguanamine and acetoguanamine,
Guanidine, guanidine hydrochloride, aminoguanidine hydrochloride,
Guanidines such as dicyandiamide are preferred, and among these, particularly preferred are urea, melamine, and benzoguanamine. Further, in the present invention, when urea is used, the effect of improving the heat fusion property is remarkable.

These polyvalent amine compounds are used in combination of two or more kinds, for example, urea-thiourea, urea-melamine, urea-
It can also be used in combination with benzoguanamine, urea-melamine-benzoguanamine, melamine-dicyandiamide and the like.

It is also possible to use a combination of the above polyvalent amine compound and the above aromatic compound, and as such a combination, for example, phenol-urea, phenol-melamine, aniline-urea, aniline-melamine, phenol-aniline. -Melamine, phenol-urea-melamine and other combinations.

Further, as the aldehyde condensable compound, in addition to the above compounds, a known ketone compound as a raw material for the ketone resin may be used. Further, the compound having two or more reaction sites with aldehydes described above is a compound having one reaction site, or a compound having two or more active reaction sites which is not an aldehyde-condensable compound per se, such as di- It can be used in combination with alkanolamine, monoalkanolamine, aliphatic amine and the like.

Further, an initial condensate of an aldehyde condensable compound and aldehydes such as dimethylol urea, hexamethylol melamine, hexamethoxymethyl melamine, etc. can be used as a forming raw material.

The ratio of the aldehyde condensable compound and the aldehydes in the reaction for forming the aldehyde condensation type fine resin particles is not particularly limited as long as it is a ratio theoretically including the ratio of the aldehyde condensation type resin generated. This is because even if the unreacted aldehyde condensable compound remains, it may be contained in the resulting dispersion unless the amount thereof is excessively large, and the unreacted aldehyde can be removed when the dispersion medium is replaced. The aldehydes are preferably used in an amount of 5 to 500% by weight, particularly 10 to 100% by weight, based on the aldehyde condensing compound.

The aldehyde condensation resin produced by this reaction is considered to be similar to or the same as a cured product of a conventionally known condensation thermosetting resin such as a phenol resin, a urea resin and a melamine resin. The reaction is also believed to be similar.

Taking the case of using formaldehyde as the aldehyde, for example, the aldehyde condensable compound and formaldehyde are subjected to addition condensation in the initial stage of the reaction to produce various methylol group-containing compounds.
The above-mentioned initial condensate, which is one of the forming raw materials of the present invention, corresponds to the methylol addition compound at this stage. Thereafter, the methylol group-containing compound is dehydrated and condensed, whereby the methylol group is converted to a methylene group and condensed to form an aldehyde condensation resin insoluble and insoluble in a three-dimensionally crosslinked solvent.

The particle diameter of the fully crosslinked aldehyde condensation resin fine particles is 0.01 to 5 μm, particularly 0.02 to 2 μm.
The range of m is preferable. If it exceeds 5 μm, it tends to settle in the dispersion medium. It is preferable that the aldehyde condensation resin fine particles do not substantially settle for 1 month or more, preferably 2 months or more when left standing. The aldehyde condensation polymer-dispersed polyol preferably has a particle size of 0.01 to 5 μm.
It is a white or colored translucent or opaque viscous liquid in which aldehyde condensation resin fine particles of m are dispersed. The viscosity is the viscosity of the dispersion medium used, the ratio of the aldehyde condensation resin in the dispersion, and the type of the aldehyde condensation resin. The viscosity of the polyurethane foam raw material of the present invention is usually 50,000 cP or less at 25 ° C. Even if the viscosity is higher than this, it may be usable by means such as dilution with various polyols.

The proportion of the polyol (C) used in the present invention is preferably 5 to 30% by weight based on the total weight of the polyol. If it is less than 5% by weight, the flame retardance is insufficient, and 3
If it exceeds 0% by weight, the proportion of the polyol (B) decreases,
Poor heat fusion.

(Flame Retardant) When the polyol (C) is used in the present invention, it is preferable not to use a flame retardant as an auxiliary agent. This is because sufficient flame retardancy can be obtained by using the polyol (C). When the polyol (C) is not used, a flame retardant is used as an auxiliary agent. When neither the polyol (C) nor the flame retardant is used, sufficient flame retardancy cannot be obtained.

Examples of the flame retardant as an auxiliary agent include halogen compounds, phosphorus compounds and melamine powder. In particular, a condensate (oligomer type) of an organohalogen phosphate compound is preferable, and a condensate of tris (monochloroisopyropyr) phosphate is particularly preferable. The amount of the organic halogen-based phosphate compound used is preferably 15% by weight or less, and particularly preferably 12% by weight or less based on the polyol.

(Others) In the present invention, polyols other than the above polyols (A) to (C) can be used. Examples thereof include a polyol mainly containing an oxytetramethylene group, a polyester polyol mainly containing a dehydration condensation product of a dicarboxylic acid and a diol, and a polyester polyol mainly containing a ring-opening polymer of a cyclic ether such as caprolactone.

Further, as the polymer active hydrogen compound other than polyol, a high molecular weight polyamine having two or more primary amino groups or secondary amino groups, or one or more primary amino groups or secondary amino groups and one or more hydroxyl groups. High molecular weight compounds can also be used in combination.

The molecular weight per functional group of these high molecular weight active hydrogen compounds is 350 or more, particularly 800 or more, and the number of functional groups per molecule is preferably 2-8. The molecular weight per functional group is preferably 10,000 or less.

Examples of such a compound include compounds obtained by converting some or all of the hydroxyl groups of the polyoxyalkylene polyol as described above into amino groups, and polyisocyanates in excess equivalent to the polyoxyalkylene polyol as described above. There is a compound obtained by hydrolyzing an isocyanate group of a prepolymer having an isocyanate group at the terminal obtained by reacting with a compound and converting it into an amino group.

(Polyisocyanate Compound) As the polyisocyanate compound in the present invention, a compound having two or more isocyanate groups or a modified product can be adopted. In particular, aromatic polyisocyanates containing aromatic nuclei are effective for flame retardancy.

Examples of the aromatic polyisocyanate include tolylene diisocyanate (TDI), diphenyl diisocyanate, polymethylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, naphthalene diisocyanate, xylylene diisocyanate, tolidine diisocyanate and triphenylmethane triisocyanate. is there.

If desired, a polyisocyanate compound having no aromatic nucleus, such as hexamethylene diisocyanate or isophorone diisocyanate, may be used together with or alone. As a modified product,
A prepolymer type modified product modified with a polyhydric alcohol such as trimethylolpropane, a carbodiimide modified product, a urea modified product, a trimerized modified product, or a dimerized modified product may be used.

The amount of the polyisocyanate compound to be used is generally 0 with respect to the total amount of the hydroxyl groups of all polyols (or the compound having a functional group capable of reacting with isocyanate groups such as water and a crosslinking agent which can be optionally used). 8 to 1.3 times equivalent, particularly 0.9 to 1.2 times equivalent are used.

(Foaming Agent) In the present invention, it is preferable to use water and / or an inert gas as a blowing agent. Specific examples of the inert gas include air and nitrogen. The amount of these foaming agents used is not particularly limited, but when only water is used, it is 1 with respect to the high molecular weight active hydrogen compound.
Up to 0% by weight, especially 0.1 to 8% by weight is suitable. Other foaming agents may be used in appropriate amounts according to the requirements such as foaming ratio.

Monochlorodifluoromethane, 1,
1-dichloro-1-fluoroethane, 1,1-dichloro-2,2,2-trifluoroethane, 1,1,1,3-
Low boiling halogenated hydrocarbons such as pentafluoropropane, 1,1,1,3,3-hexafluoropropane and 1,1,1,2-tetrafluoroethane may be used in combination.

(Catalyst) When the polyol is reacted with the polyisocyanate compound, an amine catalyst or an organometallic compound catalyst is usually used.

In the present invention, addition of the amine catalyst is not essential. Depending on the conditions such as the curing property, the amine catalyst is not used, or even if it is used, it is less than 0.35% by weight based on the total polyol.

When an amine-based catalyst is used, its amount is [1 / a + 0.15], where a is a weight% of the high-molecular weight piperazine-based polyol in all polyols.
It is particularly preferably less than wt%. That is, the use amount of the amine catalyst can be reduced by increasing the use ratio of the high molecular weight piperazine polyol. 0.15% by weight
Most preferably, it is less than.

Examples of amine-based catalysts include triethylenediamine and bis [(2-dimethylamino) ethyl] ether. Further, a reactive amine-based catalyst in which a part of the structure of the amine-based catalyst is hydroxylated or aminated so as to react with isocyanate can also be used. As the reactive amine-based catalyst, N, N-dimethylethanolamine HO
CH ₂ CH ₂ N (CH ₃ ) ₂ , 2 ethylene oxide adduct of N, N-dimethylethanolamine H (OCH ₂ C
H ₂ ) ₃ N (CH ₃ ) ₂ , trimethylaminoethylethanolamine HOCH ₂ CH ₂ N (CH ₃ ) CH ₂ CH
_{There are 2} N (CH ₃ ) ₂ .

Examples of the organometallic compound catalysts include organic tin compounds, organic bismuth compounds, organic lead compounds and organic zinc compounds. Specifically, for example, di-n-
Butyltin oxide, di-n-butyltin dilaurate, di-n-butyltin, di-n-butyltin diacetate, di-n-octyltin oxide, di-n-octyltin dilaurate, monobutyltin trichloride, di-n-butyltin Dialkyl mercaptan, di-n-octyl tin dialkyl mercaptan, and the like. When an organometallic compound-based catalyst is used, the amount used is preferably up to 1.0 part by weight, particularly preferably 0.005 to 1.0 part by weight, based on 100 parts by weight of the polymer active hydrogen compound.

Various components may be used as an auxiliary agent other than the above. For example, in most cases, a foam stabilizer is an almost essential component, and for example, a silicone-based foam stabilizer such as polyalkylsiloxane and polyalkylsiloxane-polyoxyalkylene block copolymer can be used. Furthermore, inorganic or organic fillers, ultraviolet absorbers, antioxidants, scorch inhibitors, and cross-linking agents such as diethanolamine and triethanolamine can be used.
Other auxiliaries may optionally be used.

The polyurethane foam of the present invention is produced using the above-mentioned raw materials by a method such as a one-shot method, a quasi-prepolymer method or a prepolymer method. The one-shot method is the most suitable. A molding method and a slab molding method are suitable as the molding method, but are not limited thereto.

The flexible polyurethane foam excellent in flame retardancy and heat fusion property according to the present invention preferably has physical properties and flame retardancy satisfying the following conditions. Physical properties: Density (JIS-K6767) 30-40 kg / m
³ , I. L. D. Hardness (ASTM-D-1564) 16
-24 kg / 314 cm ² , impact resilience (JIS-K6
401) 40-60%. Flame-retardant: Passes the US automobile safety standard (FMVSS-302).

The use of the polyurethane foam obtained by the production method of the present invention is not limited, but preferably has a high heat-sealing property and the addition amount of the amine-based catalyst is suppressed, so that the low fogging property is excellent. Therefore, it can be used as a foam for frame lamination.

The present invention is also a method for producing a laminated foam, characterized in that the flexible polyurethane foam and a substrate such as a cloth are laminated and integrated by heat fusion.

[0087]

EXAMPLES The present invention will be described below with reference to Examples (Examples 1 to 6) and Comparative Examples (Examples 7 to 10). Parts are parts by weight. The polyols A to I used are shown below.

Polyol A: Hydroxyl value of 56 in 5 L reactor
Of polyoxypropylene triol, 400 g of polyoxypropylene diol obtained by reacting 1 mol of bisphenol A with 3 mol of propylene oxide
Then, 0.2 g of triethylenediamine was charged and heated to 100 ° C. with stirring. Then, 174 g of tolylene diisocyanate (TDI) was added and reacted at 100 ° C. for 8 hours to obtain polyol A. The viscosity (25 ° C, the same below) was 1500 cP.

Polyol B: Hydroxyl value of 10 in 5 L reactor
1700 g of polyoxypropylene polyol of 0, 444 g of phthalic anhydride and 6 g of 95% potassium hydroxide were charged and reacted at 120 ° C. for 2 hours while stirring. Then, 1050 g of propylene oxide was added, and the temperature was 120 ° C.
To react all of the propylene oxide with polyol B
I got The viscosity was 2000 cP.

Polyol C: Molecular weight 3000 obtained by reacting PO with glycerin as an initiator, hydroxyl value 5
6 mg KOH / g oxypropylene ethylene triol.

Polyol D: EO obtained by reacting PO with glycerin as an initiator and then reacting with EO
Content 13% by weight, molecular weight 3000, hydroxyl value 56 mgK
OH / g oxypropylene ethylene triol.

Polyol E: N- (2-aminoethyl)
React PO with piperazine as initiator, then EO
EO content 12% by weight, molecular weight 30
00, an oxypropylene ethylene polyol having a hydroxyl value of 56 mgKOH / g.

Polyol F: Polyol D in a 5 L reaction tank
2,400 parts of urea, 600 parts of urea and 1300 parts of a 37% formalin aqueous solution were charged and reacted at 100 ° C. for 4 hours while stirring. After that, dehydration under reduced pressure was performed to obtain white viscous fine particle-dispersed polyol F. The viscosity of this polyol was 2800 cP, and the resin fine particles in this polyol were stably dispersed for 6 months or longer without separation. The fine particle concentration was 30% by weight.

(Examples 1 to 10) To 100 parts of the polyol mixture shown in Tables 2 to 3, 5.0 parts of water and a solution of triethylenediamine as a amine catalyst (trade name "Dabco 33LV") in the amounts shown in the table (unit: parts) ), 1.5 parts of silicone-based foam stabilizer,
A mixture was obtained by mixing 0.20 parts of stanna octoate and a condensate of tris (monochloroisopropyl) phosphate as a flame retardant in the amounts shown in the table (unit: parts).
1.05 times the equivalent of TDI with respect to the total amount of hydroxyl groups in this mixture
Was used to produce a flexible polyurethane foam by the one-shot method.

The polyurethane foam block produced as described above was cut into a proper size, and the physical properties of the polyurethane foam were measured according to the criteria shown in Table 1.

Next, a combustion test was conducted according to the FMVSS-302 standard. However, in the result of the combustion test, the non-combustibility (that is, showing that it passed) was judged to be N. B. Was expressed.

A sample (size = 50 mm × 50 mm × 100 mm) dried with a desiccator for 24 hours was put in a glass bottle having a diameter of 47 mm, and the total light transmittance was 0.4%.
The upper part was sealed with the following glass plate and heated in an oil bath at 80 ° C. for 20 hours. Then, a fogging test was conducted by measuring the total light transmittance of the glass plate.

Sheets having widths of 150 mm and 10 mm were cut out, the surface was heated and melted with a flame, and a nylon cloth was laminated with a roll. After allowing the laminate to stand for one day under constant pressure, a test piece having a width of 25 mm was cut out, and this was applied to an Instron meter to measure the peel strength. The moldability was rated as good and the defect was rated as bad. The results are shown in Table 2 (Examples) and Table 3 (Comparative Examples).

Examples 7-10 are compared with Examples 1-6. In Example 7, since the addition amount of the polyol E is small, it is necessary to add a large amount of the amine-based catalyst from the viewpoint of reactivity. As a result, the low fogging property deteriorates. In Example 8, when the addition amount of the polyol E is large, the ratio of the modified polyol in the total polyol becomes relatively small, so that sufficient heat fusion property cannot be obtained.

When the flame retardant was not added in Examples 9 to 10, Example 9 had good low fogging property but poor flame retardancy.
However, since Polyol F is added, the flame resistance is good, but the heat fusion property is poor.

On the other hand, in Examples 1 to 4, since the amount of the amine-based catalyst can be reduced even though the flame retardant is added, the physical properties of the foam, particularly the heat-sealing property and the low fogging property are good. Further, in Examples 5 to 6, since the polyol F is added, the flame retardancy is good and the low fogging property is excellent even though the flame retardant is not added.

[0102]

[Table 1]

[0103]

[Table 2]

[0104]

[Table 3]

[0105]

INDUSTRIAL APPLICABILITY The flexible polyurethane foam according to the present invention can reduce the amount of the amine-based catalyst added while maintaining the heat-sealing property, and the flame test based on FMVSS-302 by using no flame retardant or by using a small amount thereof. Have the characteristics that can pass.

Claims (9)

[Claims] 1. A soft material obtained by reacting a high molecular weight active hydrogen compound having two or more active hydrogen-containing groups capable of reacting with an isocyanate group and a polyisocyanate compound in the presence of a foaming agent, a foam stabilizer, a catalyst and other auxiliaries. In the production of polyurethane foam, (1) a mixture of the following polyol (A), polyol (B) and polyol (C) is used as at least a part of the high molecular weight active hydrogen compound, and (2) an amine-based catalyst is used. A method for producing a flexible polyurethane foam having excellent flame retardancy and thermal fusion resistance, characterized by using no or less than 0.35% by weight of an amine-based catalyst based on the total polyol. Polyol (A): A high molecular weight piperazine-based polyol obtained by ring-opening addition polymerization of an alkylene oxide to piperazines. Polyol (B): A modified polyether polyol selected from urethane modified polyether polyol and ester modified polyether polyol. Polyol (C): Fine particle-dispersed polyol having fine particles of aldehyde condensation resin as a dispersoid. 2. A flame retardant is not used as an auxiliary agent.
Manufacturing method. 3. A flexible compound obtained by reacting a high molecular weight active hydrogen compound having two or more active hydrogen-containing groups capable of reacting with an isocyanate group and a polyisocyanate compound in the presence of a foaming agent, a foam stabilizer, a catalyst and other auxiliaries. In the production of a polyurethane foam, (1) a mixture of the following polyol (A) and polyol (B) is used as at least a part of the high molecular weight active hydrogen compound, (2) a flame retardant is used as an auxiliary agent, and (3) Amine-based catalyst Amine-based catalyst is not used, or 0.3 based on all polyols.
A method for producing a flexible polyurethane foam having excellent flame retardancy and heat fusion characteristics, which comprises using an amine-based catalyst in an amount of less than 5% by weight. Polyol (A): A high molecular weight piperazine-based polyol obtained by ring-opening addition polymerization of an alkylene oxide to piperazines. Polyol (B): A modified polyether polyol selected from urethane modified polyether polyol and ester modified polyether polyol. 4. A urethane-modified polyether polyol,
The method according to any one of claims 1 to 3, which is a urethane-modified polyether polyol obtained by reacting a polyether polyol with a polyisocyanate compound in an amount of less than 1 time. 5. An ester-modified polyether polyol,
An ester-modified polyether polyol obtained by reacting a polyether polyol with a polycarboxylic acid anhydride and then reacting it with an alkylene oxide.
3. The manufacturing method according to any one of 3 above. 6. The production method according to claim 1, wherein the amount of the polyol (A) used in all the polyols is 5 to 35% by weight. 7. When an amine-based catalyst is used, its amount is less than [1 / a + 0.15]% by weight based on the amount of the polyol (A) used in all polyols as a% by weight.
The manufacturing method according to claim 1. 8. The method according to any one of claims 1 to 7, wherein the flexible polyurethane foam is a flexible polyurethane foam having flame retardancy that passes US Motor Vehicle Safety Standard (FMVSS-302). 9. A method for producing a laminated foam, characterized in that the flexible polyurethane foam obtained by the method according to any one of claims 1 to 8 and a substrate such as a cloth are laminated and integrated by heat fusion.