JP2881844B2 - Method for producing aldehyde condensation resin dispersion - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a condensation resin dispersion suitable for producing polyurethane.

[Prior Art] Conventionally, what is called a polymer polyol or a graft polyol has been known as a polyol for a polyurethane raw material. This is one in which an addition polymerization type polymer is grafted on the molecular chain of a polyol such as a polyether polyol or unsaturated polyol, or an addition polymer or other polymer is simply dispersed in the polyol. .

As a method for producing this kind of polymer polyol, a method of polymerizing a vinyl monomer such as acrylonitrile or styrene in a liquid polyol, a method of simply dispersing a polymer such as a previously produced vinyl polymer or the like in a polyol, A method of grafting the coalesced to a polyol is known. The polymer in such conventional polymer polyols is almost always a vinyl polymer, except for those in which a linear polyester is dispersed.

It is also known to use an amino resin precondensate as a polyurethane raw material. Since the amino resin precondensate has a hydroxyl group capable of reacting with an isocyanate group such as a methylol group, a polyurethane foam or the like can be obtained by reacting this with a polyisocyanate compound (JP-A-53-16798, etc.).

Further, an etherified amino resin precondensate obtained by etherifying a part of the methylol group of the amino resin precondensate,
It is also known that a mixture with a usual polyol for a polyurethane raw material is used as a raw material for producing a polyurethane foam (Japanese Patent Laid-Open Publication No. 52-153000). A method for performing this has already been proposed (JP-A-54-101848).

[Problems to be Solved by the Invention] The conventional polyurethane raw materials described above still have various problems.

First, so-called polymer polyols are suitable as raw materials for highly elastic polyurethane foams, but they have no effect on, for example, flame retardancy of polyurethane, but rather have an unsolved problem of lowering flame retardancy.

On the other hand, the amino resin precondensate-containing polyol is a polyurethane foam which is a feature of the polymer polyol because the amino resin precondensate is a relatively low molecular weight polyol and not as high in molecular weight as the polymer in the polymer polyol described above. It is difficult to exhibit the high elasticity effect of
It is hardly recognized as a kind of polymer polyol because its use is limited to rigid polyurethane foam.

On the other hand, a method of filling polyurethane with a crosslinked high molecular weight condensation resin powder as a filler to make the polyurethane flame-retardant is also known, but such a filler is stably dispersed in a polyol. Is difficult, the dispersion stability is inferior to that of a so-called polymer polyol, and this is disadvantageous in terms of polyurethane production.

Furthermore, Japanese Patent Publication No. 57-14708 proposes a method for producing a dispersion of aminoplast condensate by condensing a substance capable of forming aminoplast in a polyhydroxy compound. However, a completely stable dispersion of resin particles could not be obtained, and only resin particles having a large particle size could be obtained.

JP-A-51-122193 describes a method of forming sedimentable particles and blending the same with a polyol or the like. However, in this case, the particle size is large, and the particles tend to settle in the polyol. In order to improve the dispersion stability of such condensation-based resin particles, it is necessary to reduce the particle size. However, when the particle size is reduced, there is a problem that sedimentation is difficult and filtration and separation are difficult.

The present invention solves various problems in the conventional polyol containing a polymer as a polyurethane raw material described above, and can be used as a raw material for producing a flame-retardant polyurethane, and has good dispersion stability and low dispersion. It is an object of the present invention to provide a novel method for producing a condensation resin dispersion having a viscosity.

[Means and Actions for Solving the Problems] As a result of various studies of condensation resin dispersions having good dispersion stability and low viscosity, the present inventors have found that the condensation resin is sufficiently crosslinked instead of an initial condensate. Excellent flame retardancy by using a dispersion obtained by dispersing this in an active hydrogen-containing compound having two or more active hydrogen-containing groups having reactivity with an isocyanate compound such as a polyol as a polyurethane raw material. It has been found that a polyurethane foam can be obtained, and that such a dispersion can be produced stably by a method of reacting in the presence of an active hydrogen-containing compound having two or more active hydrogen-containing groups and specific polyurea fine particles. Was.

That is, the present invention provides a polyaddition reaction between a diamine and an aromatic diisocyanate in an active hydrogen compound to obtain an active hydrogen compound in which polyurea fine particles are dispersed in the active hydrogen compound. An aldehyde condensation resin dispersion, characterized in that a compound capable of condensing with aldehydes and an aldehyde or an initial condensate thereof are subjected to a condensation reaction to precipitate fine condensation resin particles in an active hydrogen compound. It is a manufacturing method of.

One of the raw materials for forming the condensation resin in the present invention is an aldehyde. Aldehydes include aliphatic, alicyclic,
Derivatives such as aromatic and heterocyclic aldehyde compounds, other aldehydes, and condensates thereof and 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, for example, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, paraformaldehyde, paraacetaldehyde and the like, Preferably it is formaldehyde.

These aldehydes can be used by dissolving in a solvent, and a particularly preferred solvent is water, but is not limited thereto. In the present invention, it is particularly preferable to use an aqueous solution of formaldehyde, that is, formalin.

Another forming raw material of the condensation resin is a compound capable of forming a solid condensation resin by condensation with an aldehyde (hereinafter referred to as an aldehyde condensable compound). Basically two). The reaction site is typically a carbon atom to which hydrogen is bonded in an aromatic nucleus, or a nitrogen atom to which hydrogen is bonded in an amino group or an amide group. The aromatic nucleus reaction site is particularly preferably an ortho-position or a para-position of the aromatic nucleus 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 a compound having an amino group or an amide group, a polyamine compound having two or more of those 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 polyamine compounds are preferable. Two or more compounds capable of reacting with these aldehydes can be used in combination, and a compound having only one reaction site can be used together with them.

As the phenols of the aromatic compounds,
For example, phenol, cresol, xylenol, p-
Examples thereof include alkylphenol, p-phenylphenol, bisphenol A, and resorcin, and phenol is particularly preferred. Examples of the aromatic amine include aniline, diaminobenzene, p-alkylaniline, N-substituted alkylaniline, diphenylamine, diaminodiphenylmethane, and the like.
More than one species can be used in combination.

Since the amino group of the aromatic amine itself is also a reactive site, the amino group of the aromatic amine may be regarded as one of the following diamine compounds, and the reactive site other than the amine group of the aromatic amine may be one. A particularly preferred aromatic amine is aniline.

The aromatic compound is not limited to the above compounds,
For example, aromatic hydrocarbons such as benzene and xylene and other compounds can also be used. Furthermore, phenols and aromatic amines can be used in combination, and one or more of them can be used in combination with other aromatic compounds.

As the polyamine compound, a compound having basically two or more amino groups or amide groups, particularly a compound having two or more amino groups is preferable, for example, urea (urea, thiourea, N-substituted urea, etc.), melamine Compounds (melamine, N-alkyl-substituted melamine, etc.), s-triazines having two or more amino groups (represented by guanamine compounds such as benzoguanamine, acetoguanamine, etc.), guanidines (guanidine, guanidine hydrochloride, aminoguanidine hydrochloride, Dicyandiamide, etc.) are preferred. Of these, urea, melamine and benzoguanamine are particularly preferred.

These polyamine compounds may be used in combination of two or more, for example, urea-thiourea, urea-melamine, urea-benzoguanamine, urea-melamine-benzoguanamine, melamine-dicyandiamide and the like.

In addition, the polyamine compound and the aromatic compound can be used in combination. Examples of such a combination include phenol-urea, phenol-melamine, aniline-urea, aniline-melamine, phenol-aniline-melamine, and phenol- Urea-melamine and other combinations.

Further, as the aldehyde condensable compound, a ketone compound known as a raw material of a ketone resin in addition to the above compounds may be used. In addition, the reaction site with the aldehyde described above is 2
The compound having one or more reactive sites is a compound having one reactive site or a compound which is not an aldehyde condensable compound but has two or more active reactive sites, such as dialkanolamine, monoalkanolamine, and aliphatic amine. Can be used together.

Further, in the present invention, an initial condensate of an aldehyde condensable compound and an aldehyde, for example, dimethylol urea,
Hexamethylolmelamine, hexakis (methoxymethyl) melamine and the like can also be used as forming raw materials.

The ratio between the aldehyde condensable compound and the aldehyde in the reaction for forming the condensation resin particles is not particularly limited as long as the ratio at which the condensation resin is theoretically generated. For example, even if unreacted aldehyde condensable compounds remain, they may be contained in the resulting dispersion as long as the amount is not excessive. Preferably, the aldehyde is used in an amount of 5 to 500 parts by weight, particularly 10 to 100 parts by weight, based on 100 parts by weight of the aldehyde condensable compound.

The condensed resin produced by this reaction is considered to be similar or identical to a cured product of a conventionally known condensed thermosetting resin such as a phenol resin, a urea resin, and a melamine resin. It is considered to be.
Taking the case where formaldehyde is used as an aldehyde as an example, the aldehyde condensable compound and formaldehyde are condensed in the initial stage of the reaction to produce various methylol group-containing compounds. The above precondensate, which is one of the raw materials for the formation of the present invention, corresponds to the methylol adduct at this stage. Thereafter, the methylol group-containing compound is dehydrated and condensed, so that the methylol group is converted to a methylene group and condensed to form a three-dimensionally crosslinked, insoluble and insoluble condensed resin.

When performing this condensation reaction, water and / or an organic solvent can be used as a dispersion medium together with the active hydrogen-containing compound. The dispersion medium is preferably one that can be removed by means such as heating and / or decompression. Preferably, a dispersion medium having a boiling point of 250 ° C. or lower, particularly 180 ° C. or lower is used, or 250 ° C. or lower, particularly 1
A dispersion medium that evaporates at 80 ° C. or lower is used, and a dispersion medium that can be removed under heating, under reduced pressure, or more preferably under heating under reduced pressure is used.

Examples of such a dispersion medium include water, aliphatic hydrocarbons (pentane, hexane, cyclohexane, hexene, etc.), aromatic hydrocarbons (benzene, toluene, xylene, etc.), and alcohols (methanol, ethanol, isopropanol, butanol). , Cyclohexanol, benzyl alcohol, etc.), ethers (isopropyl ether, tetrahydrofuran, benzyl ethyl ether, acetal, anisole, etc.), ketones (acetone, methyl ethyl ketone, acetophenone, etc.), esters (ethyl acetate, butyl acetate, etc.), halogen Hydrocarbons (chlorobenzene, chloroform, dichloroethane, 1,1,2-
Trinitrotrifluoroethane, etc.), nitro compounds (nitrobenzene, etc.), nitriles (acetonitrile, benzonitrile, etc.), amines (trimethylamine, triethylamine, tributylamine, dimethylaniline, etc.), amides (N, N-dimethylformamide, N -Methyl-2-pyrrolidone, etc.) and sulfur compounds (dimethylsulfoxide, sulfolane, etc.). In the present invention, these dispersion media can be used alone or as a mixture.

The active hydrogen-containing compound described below is a compound which usually has a very high boiling point or substantially no boiling point (decomposes without heating as a gas without heating). Even if it has a boiling point, the boiling point usually exceeds 250 ° C. Even if the active hydrogen-containing compound has a boiling point of 250 ° C. or lower, a compound having a boiling point of 20 ° C. or higher, preferably 50 ° C. or higher than the boiling point of the dispersion medium to be used is preferable. Conversely, when using such an active hydrogen compound having a relatively low boiling point, the boiling point is 20 ° C. lower than the boiling point.
As described above, it is preferable to use a dispersion medium having a boiling point lower by 50 ° C. or more.

One of the features of the present invention is that the condensation reaction is basically terminated. Whether or not the crosslinking is sufficient can be determined from the fact that the methylol group generated in the early stage of the reaction is converted into a methylene group and the hydroxyl value becomes smaller. That is, in the case of using a polyol as the active hydrogen-containing compound, when comparing the hydroxyl value of the polyol and the obtained dispersion, if the hydroxyl value of the dispersion is increased, the crosslinking is insufficient. The presence of a methylol group is considered, and if the hydroxyl value is equal to or less than that, it is considered that sufficient crosslinking has been performed.

The particle size of the fully crosslinked condensation resin particles of the present invention is 0.
The range is preferably from 01 to 5 μm, particularly preferably from 0.1 to 2 μm. If it exceeds 5 μm, it tends to precipitate in an active hydrogen-containing compound such as a polyol. It is preferable that the condensed resin particles do not substantially settle for one month or more, preferably two months or more when left standing.

Hereinafter, the step of obtaining the condensable resin compound will be described more specifically. The aldehyde condensable compound and the aldehyde react under normal temperature to heating and / or under pressure. It is considered that at a relatively low temperature, a methylol group-containing compound to which an aldehyde is added or a low molecular weight condensate is easily formed, and at a relatively high temperature, a methylene bridge or a dimethylene ether bond due to a dehydration reaction of a methylol group or the like is likely to be formed. Of course,
The generated compound is not only related to the reaction temperature but varies depending on the charging ratio of each structural unit, the presence of an additive such as a catalyst, the pH, and the like.

However, considering only the reaction temperature, in the present invention, it is preferable to carry out the reaction at a relatively low temperature in the first stage of the reaction and at a relatively high temperature in the stage of the reaction. In particular, a relatively high temperature in the latter stage of the reaction is often necessary for the condensation reaction of a hydroxyalkyl group such as a methylol group to occur. Therefore, the reaction is preferably carried out at a reaction temperature of about 80 ° C. or lower in the first stage of the reaction, and at a temperature of about 10 ° C. higher than that of the first stage and about 60 ° C. or higher in the latter stage.

The upper limit temperature in the latter stage of the reaction is preferably a temperature at which side reactions other than the decomposition reaction of the active hydrogen-containing compound and the formation reaction of the condensation-based resin hardly occur, and 80 when the active hydrogen-containing compound reacts with water in the presence of water. The temperature is particularly preferably about 80 to 100 ° C. under normal pressure, and preferably about 80 to 200 ° C. in the coexistence system of an active hydrogen compound and an organic solvent or water and an organic solvent.

An acid such as hydrochloric acid or acetic acid, or a base such as sodium hydroxide or triethylamine can be used as a catalyst in order to allow the condensation reaction to proceed at a relatively low temperature. It is also effective to add a small amount of a particle stabilizer such as a surfactant during the condensation reaction in order to increase the stability of the condensation resin particles. Further, the reaction can be carried out in the presence of various additives such as a curing agent such as hexamethylenetetramine, a dispersion stabilizer, and a coloring agent.

It is not preferable that the active hydrogen compound used as a raw material of the polyurethane contains a relatively large amount of water. Therefore, the water initially present at the time of the reaction must be removed when displacing the polyol. Usually, water can be removed under heating or under reduced pressure. In addition, 25
It can be removed by heating at 0 ° C. or lower and / or under reduced pressure. When the condensation-based resin particle precipitation reaction is performed in the presence of water and / or an organic solvent as a dispersion medium in the presence of high-molecular-weight resin fine particles having reactivity with an active hydrogen compound and an aldehyde, the precipitated dispersion liquid contains An active hydrogen compound is added, and water and / or
Alternatively, the organic solvent can be removed under heating and / or reduced pressure.

As the active hydrogen-containing compound in the present invention, the active hydrogen-containing group is a hydroxyl group, a primary amino group, and / or a secondary amino group, and two or more active hydrogen-containing groups per molecule;
It preferably has 2 to 8 and has a molecular weight per active hydrogen-containing group of 100 to 1000, preferably 200 to 7000, particularly preferably
Suitable active hydrogen compounds having a molecular weight of 400 to 5000 are, for example, polyether polyols or polyester polyols, hydrocarbon polymers having a terminal hydroxyl group and so-called polymer polyols, and polyether polyols are particularly preferred.

Examples of the compound having an amino group include polyether polyols, aminated polyethers in which some or all of the hydroxyl groups of the polyester polyol are substituted with primary or secondary amino groups, and mixtures thereof.

Examples of the polyether polyol include a polyhydroxy compound such as a polyhydric alcohol, an amine, a polyether polyol obtained by adding an alkylene oxide to an active hydrogen compound such as phosphoric acid, and a polyether polyol formed of a cyclic ether polymer.

Specifically, polyhydric alcohols (glycol, glycerin, trimethylolpropane, pentaerythritol,
For sorbitol, dextrose, sucrose, and others), alkanolamine (diethanolamine, triethanolamine, and others), polyhydric phenol (bisphenol A, phenol-formaldehyde condensate, and others), and amines (ethylenediamine, diaminodiphenylmethane, and others) And alkylene oxides (ethylene oxide, propylene oxide, butylene oxide, epichlorohydrin, etc.), polyether polyols to which epoxides such as styrene oxide and glycidyl ether are added, and polyether polyols such as tetrahydrofuran polymers. These are 2
More than one species may be used in combination.

Preferred polyether polyols are polyether polyols having a molecular weight of 200 to 7000 per hydroxyl group, particularly 400 to 5,000 molecular weight per hydroxyl group and 2 to 8 hydroxyl groups.
Are preferred.

As the aminated polyol, those obtained by aminating a polyether polyol with ammonia, those obtained by hydrolyzing an isocyanate group-containing prepolymer obtained by reacting a polyether polyol with a polyisocyanate can be used, The former is particularly preferred.

In addition, of the same type as the active hydrogen compound as described above,
Polyhydric alcohols having a lower molecular weight than the above, esters containing hydroxyl groups such as polyhydroxyesters and the like are used, and as the polyhydric alcohol, among the above-mentioned polyethers, polyesters and liquids which can be used as initiators of polyether polyols, Those and the like can also be used.

The polyurea fine particles as high molecular weight resin fine particles having reactivity with aldehyde, which is another component to be present at the time of the condensation reaction, contribute to exhibiting the stability of the aldehyde condensation resin of the present invention. .

In order to make these resin fine particles, in the case of the present invention, the resin fine particles are formed by previously reacting a diamine and an aromatic diisocyanate in the presence of an active hydrogen compound coexisting when producing an aldehyde condensation resin dispersion. Let it be.

In this case, taking the example of using a polyether polyol as the active hydrogen compound, the reaction between the diamine and the aromatic diisocyanate is extremely fast, so the reaction between the diamine and the aromatic diisocyanate has priority over the polyether polyol which is the active hydrogen compound. Thus, a polyether polyol composition in which stable polyurea fine particles are dispersed can be obtained. Here, the reaction of the diamine and the aromatic diisocyanate takes precedence, but it is considered that the reaction of the aromatic isocyanate and the polyether polyol may partially occur, and these are effective grafts for forming aldehyde condensation resin particles later. It could also act as a point.

The amount of the polyurea fine particles is sufficiently effective in the presence of 0.01% by weight of the produced aldehyde condensation resin, and is preferably
An amount of 0.1 to 10% by weight is employed.

The amount of the condensed resin dispersed with respect to the active hydrogen compound in the dispersion of the present invention is not particularly limited as long as the condensed resin is stably dispersed. Therefore, in general, the content of the condensed resin is preferably 200 parts by weight or less, particularly preferably 100 parts by weight or less based on 100 parts by weight of the active hydrogen compound. Although there is no particular limitation, it is preferable that about 5 parts by weight or more of a condensed resin is present with respect to 100 parts by weight of the active hydrogen compound in order to exert the effect of the dispersion of the present invention in the production of polyurethane.

The solid condensed resin dispersion of the present invention obtained as described above is preferably a white or colored translucent or opaque viscous liquid in which condensed resin particles having a particle size of 0.1 to 5 μm are dispersed, and the viscosity is determined by the active hydrogen content used. Although it varies depending on the viscosity of the compound, the proportion of the condensation resin in the dispersion, the type of the condensation resin, and the like, a polyurethane raw material having a viscosity at 25 ° C. of usually 50,000 cP or less is suitable. Even if the viscosity is higher than this, it can be used in some cases by means such as dilution with another active hydrogen-containing compound.

In the dispersion of the present invention, it may be considered that the grafting reaction of the condensation resin of the active hydrogen compound does not basically occur, but the aldehyde-reactive polyurea fine particles coexisting as described above contain the active hydrogen compound. When the aldehyde-condensed resin particles are chemically bonded to the aldehyde-condensed resin particles, an indirect grafting reaction is considered, which may contribute to stabilization of the dispersion of the aldehyde condensation resin particles.

In the present invention, in the case of a dispersion using an active hydrogen compound containing an aromatic nucleus, an amino group, or an amide group, a particularly good dispersion state can be obtained because of good affinity with the condensation resin.

The condensation resin dispersion according to the present invention is preferably one which does not cause separation in a standing state for about 1 month or more, particularly for 2 months or more, but is not limited to this period. The reason why the product of the present invention has such excellent dispersion stability is presumed to be that the particle diameter of the condensation resin fine particles is fine and uniform.

The hydroxyl value of the condensed-diameter resin dispersion of the present invention mainly relates to the hydroxyl group of the active hydrogen-containing compound. In the present invention, the hydroxyl value of the active hydrogen compound is usually preferably 800 or less,
Particularly, in the case of a polyol having a high molecular weight of 400 to 5,000 per hydroxyl group, the hydroxyl value is about 22 to 140.

As described above, in the dispersion of the present invention, since the condensation resin is sufficiently crosslinked, it has almost no functional group containing a hydroxyl group such as a methylol group. As compared to that of the activated hydrogen-containing compound, the hydroxyl group of the dispersion does not become much higher and is lower than the hydroxyl value of the active hydrogen compound in proportion to the content of the condensation resin. It is preferably 1.2 times or less, particularly preferably equal to or less than that of the above. However, when a hydroxyl group-containing compound such as a phenol compound is used as the aldehyde condensable compound, the hydroxyl value of the dispersion may be higher than the hydroxyl value of the active hydrogen compound.

In the case of a known amino resin precondensate-containing polyol, if the hydroxyl value of the polyol used is higher than that of the amino resin precondensate, the hydroxyl value of the dispersion polyol is lower than that of the original polyol, but dimethylol. When a high hydroxyl value such as urea or polymethylol melamine is as high as about 600 or more as a component of the amino resin precondensate, a dispersion using a polyol having a low hydroxyl value (that is, high molecular weight) is used. Is a hydroxyl value significantly higher than the hydroxyl value of the polyol.

The condensation resin dispersion of the present invention obtained by the above-described production method is particularly suitable for use as a part or all of the active hydrogen-containing compound as a main raw material in polyurethane production. Further, the condensation resin dispersion of the present invention containing a relatively low molecular weight active hydrogen compound can also be used as a part or all of a crosslinking agent which is an auxiliary material of polyurethane.

Whereas conventional polymer polyols have rather reduced the flame retardancy of polyurethane, the condensation resins of the present invention improve the flame retardancy of polyurethane. In particular, the condensation resin dispersion of the present invention mainly using a phenolic compound, a urea compound, a melamine compound or a guanamine compound, or a guanidine compound is particularly effective for improving the flame retardancy of polyurethane.

As a polyol as a basic raw material of polyurethane,
Generally, a high molecular weight polyol having a molecular weight of 300 to 3,000 per hydroxyl group, particularly, a molecular weight of 600 to 2 per hydroxyl group.
A polyether polyol having a hydroxyl number of 2 to 8 in the molecule of 500 is used, and a polyol having a lower molecular weight than the above is used for a rigid polyurethane foam. Therefore, when the condensed resin dispersion of the present invention is used as a part of a polyurethane raw material, the above-mentioned conventionally used high molecular weight polyol is suitable as another polyol used in combination therewith.

In the production of polyurethane, polyhydric alcohol is further added to the basic materials of polyol and polyisocyanate compound,
In some cases, a cross-linking agent comprising an active hydrogen-containing compound having a relatively low molecular weight and containing two or more active hydrogen-containing groups such as alkanolamine and polyamine is used. The condensation resin dispersion, particularly the condensation resin dispersion obtained by using a low molecular weight polyol, can be used as a part or all of the crosslinking agent.

As the polyurethane in the present invention, a polyurethane foam is most suitable. The condensation resin dispersion of the present invention can be used in the same manner as a conventional polymer polyol to obtain a high-performance polyurethane foam.

In the production of polyurethane foams it is usually necessary to use blowing agents. As the blowing agent, water, trichlorofluoromethane, dichlorodifluoromethane, dichlorotrifluoroethane, dichloromonofluoroethane, methylene chloride and other halogenated hydrocarbons are used.

In addition, a component often required in the production of polyurethane foams is a foam stabilizer. As a foam stabilizer,
Poly (dialkylsiloxane), polyoxyalkylene chain-containing silanes and other organosilicon compounds are suitable, but fluorine-based surfactants can be used in some cases.

Catalysts are usually used in the production of foamed or non-foamed polyurethanes. As the catalyst, various tertiary amines, other amine compounds, organic tin compounds and the like are used alone or in combination.

Various additives as raw materials for other foamed or non-foamed polyurethanes, such as stabilizers, fillers, reinforcing agents,
Colorants, release agents, crosslinking agents, chain extenders, and flame retardants can be used.

Another basic raw material for polyurethane is a polyisocyanate compound. As the polyisocyanate compound, an aromatic compound having two or more isocyanate groups, an aliphatic compound,
Compounds such as alicyclic and heterocyclic compounds can be used alone or in combination, and the use of aromatic polyisocyanate compounds is particularly preferred.

Specific examples of polyisocyanate compounds include tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), polymethylene polyphenyl isocyanate, xylylene diisocyanate, naphthalene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. The polyisocyanate compound can also be used as a modified polyisocyanate compound modified by various methods or compounds, and can also be used as a blocked isocyanate compound blocked with various compounds.

The method for producing polyurethane using these raw materials is not particularly limited, and for example, a method such as a one-shot method, a prepolymer method, or a RIM method can be used.

In the present invention, the mechanism of action for obtaining a condensation resin dispersion having good dispersion stability and low viscosity is not necessarily clear, but it can be estimated that the condensation resin particles are fine and uniform.

[Examples] Hereinafter, the present invention will be described in more detail with reference to examples. In each example, parts mean parts by weight. Note that the present invention is not limited by these examples.

Preparation Example 1 (Production of Polyurea Resin Fine Particle-Dispersed Polyol) 900 parts of polyoxypropyleneoxyethylene triol having a molecular weight of 5000 starting with glycerin, and ethylenediamine 25
Then, 75 parts of tolylene diisocyanate was gradually added dropwise at room temperature while stirring vigorously. The mixture gently generated heat and became cloudy at the same time as the dropwise addition. After dropping, heat to 80 ° C.
Stirring was continued for an hour to obtain a white viscous polyol composition in which polyurea fine particles were uniformly dispersed.

Example 1 2000 parts of polyoxypropylene oxyethylene triol having a molecular weight of 5,000 starting with glycerin and 50 parts of melamine were introduced into a reactor.
0 parts, 700 parts of a 35% formalin aqueous solution, and 500 parts of the polyurea-dispersed polyol of Preparation Example 1 were charged at 100 ° C. while stirring was continued.
For 4 hours, followed by dehydration under reduced pressure to obtain a white viscous polyol dispersion.

It has a hydroxyl value of 28.0 and a viscosity of 2800 cP (temperature 25
° C, the same applies hereinafter). It was found that the solid particles in the polyol were stably dispersed without separating from the polyol at all for 6 months or more.

Example 2 2500 parts of polyoxypropyleneoxyethylenetriol having a molecular weight of 7,000 starting with glycerin, 500 parts of hexakis (methoxymethyl) melamine, 200 parts of urea, 500 parts of water, and 300 parts of the polyurea-dispersed polyol of Preparation Example 1 were charged at 60 ° C. For 1 hour and further at 100 ° C. for 2 hours. In the system, a pale dispersion in which the particles were emulsified on the way and the fine particles were dispersed was obtained. The water was removed from the dispersion under reduced pressure to obtain a bluish white viscous emulsion.

This product has a hydroxyl value of 22.8, a viscosity of 2100 cP, and 3
It has been stable for more than a month.

Example 3 400 parts of urea, 100 parts of dicyandiamide, 80 parts of the polyurea-dispersed polyol of Preparation Example 1, and 1000 parts of 35% formalin were heated at 60 ° C.
For 2 hours and at 90 ° C. for 3 hours to obtain a white viscous emulsion. To this viscous emulsion, start adding 1500 parts of sorbitol, add 1500 parts of polyoxypropyleneoxyethylene hexaol having a molecular weight of 15,000, stir well, remove the water under reduced pressure, and basically remove the water. A polyol composition was obtained.

This had a hydroxyl value of 17.3 and a viscosity of 6,300 cP, and it was found that the solid particles in the polyol were stably dispersed without separating from the polyol at all for 6 months or more.

Comparative Example 1 As a result of performing a reaction having the same composition as in Example 1 but not containing the polyurea-dispersed polyol of Preparation Example 1, a white uniform dispersion was obtained, but sedimentation of particles was observed within 3 months. .

[Effects of the Invention] The present invention relates to a method for producing a dispersion in which particles of an aldehyde condensation resin are dispersed in a polyol, in which a condensation reaction proceeds in the presence of polyurea fine particles having reactivity with a polyol and an aldehyde. The method of precipitating the aldehyde condensed resin particles has an effect that a dispersion having excellent dispersion stability of the particles can be obtained.

Claims (3)

(57) [Claims] 1. An active hydrogen compound comprising a polyaddition reaction between a diamine and an aromatic diisocyanate in an active hydrogen compound to obtain an active hydrogen compound in which polyurea fine particles are dispersed in the active hydrogen compound. An aldehyde condensation resin dispersion, characterized in that a compound capable of condensing with aldehydes and an aldehyde or an initial condensate thereof are subjected to a condensation reaction to precipitate fine condensation resin particles in an active hydrogen compound. Manufacturing method. 2. The active hydrogen-containing compound has 2 to 8 hydroxyl groups and / or amino groups and has a molecular weight per active hydrogen-containing group.
The method of claim 1, wherein the number is 100 or more. 3. The method according to claim 1, wherein the aromatic diisocyanate is tolylene diisocyanate.