JPH0521146B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for forming a flame-retardant foam from a specific synthetic resin emulsion containing a specific substance and a flame retardant, and more specifically,
The present invention relates to a method for stably forming a modified high-strength flame-retardant foam from a urethane emulsion containing a propylene oxide random copolymer, a conjugated diene and/or vinyl polymer emulsion, and a flame retardant. The flame-retardant foam of the present invention can be injected into a mold to form a foamed molded product that can retain its shape when the foam layer is in close contact with a base material such as a textile, and has flame-retardant and modified properties. Due to its high physical properties, it is useful in a wide range of industrial fields. It is particularly suitable for use as a flame-retardant foam coating for car seats. [Prior Art] Traditionally, blowing agents, coagulants, crosslinking agents and other additives are added to natural and synthetic resin emulsions.
A known method is to mechanically foam the material, apply it onto a substrate or inject it into a mold, and then dry, solidify, and cure it to form a foam. Such natural and synthetic resin emulsions include natural rubber latex, styrene-butadiene copolymer emulsion, acrylonitrile-butadiene copolymer emulsion, and acrylic acid ester copolymer emulsion. The formed foams are used in a variety of applications due to their structural advantages such as light weight, wall thickness, texture, and feel. However, many of these foams are inferior in performance such as mechanical strength and durability, and in order to be used in a wider range of applications, improvements such as higher strength and higher durability are required. For example, in the case of natural rubber and butadiene-based copolymers, improvements in durability such as light resistance and heat resistance and mechanical strength are achieved, while in the case of acrylic ester copolymers, mechanical strength, solvent resistance, and cold resistance are improved. It is necessary to improve properties such as properties or elasticity. Various methods have also been proposed for forming foams from polyurethane emulsions, and these foams are attracting attention as having high performance that has improved the above-mentioned drawbacks. However, polyurethane emulsions are not satisfactory in terms of foam moldability using conventionally proposed mechanical foaming methods, and the inherent properties of the resin have not yet been exploited for a wide range of applications, and improvements are needed. For example, high foaming ratio,
It is unsatisfactory in terms of stable and wide foaming moldability that allows the formation of foams with high coating thickness and requires improvement. On the other hand, it is known that a flame retardant is added to a synthetic resin emulsion and applied to a base material (non-foamed) to impart flame retardancy, but the combined use of a flame retardant tends to reduce the strength of the synthetic resin film. It is in. This is because flame retardants are generally in liquid or insoluble powder form. It has also been proposed to add a flame retardant to a synthetic resin emulsion, mechanically foam it, and apply the foamed liquid to a substrate to impart flame retardancy. For example, there is Japanese Patent Publication No. 44-24272 which is based on a vinylidene chloride synthetic resin emulsion based on a special manufacturing method. or,
There is also a proposal suggesting the possibility of adding flame retardants to general polyurethane emulsion foams (Special Publication No. 58
−36112). However, the former requires a large amount of chlorine content and has the disadvantage of being inferior in flexibility and rebound, while the latter solves the aforementioned unsatisfactory foam moldability in urethane emulsion foaming by adding a flame retardant. It will only make things worse. In this way, when forming a foam from a synthetic resin emulsion, it is desirable to have both excellent foam physical properties such as high strength and high durability, and foam moldability that allows it to be freely molded into a stable and industrially useful form. Although there is a strong demand for flame retardancy in addition to these properties, it has not been possible to achieve this. [Problems to be Solved by the Invention] An important and difficult technical issue in such prior art is foam moldability. In other words, it is necessary to generate and maintain fine and uniform air bubbles when foaming the emulsion, and to coalesce or eliminate air bubbles from an aqueous dispersion called emulsion, which essentially has no strength and forms partition walls containing air bubbles. The objective is to form a resin film strong enough to withstand permanent bubble retention without forming bubbles. That is, contradictory properties are required, firstly, the ability to stabilize the dispersion of the emulsion, and secondly, the ability to destabilize the dispersion to quickly fuse the dispersed resin particles.
Therefore, the method of improving physical properties by combining different types of emulsions, which is adopted in non-foaming systems, is similar to that in foaming systems.
This was difficult because the dispersion stabilizing ability and destabilizing ability of each emulsion were different. Furthermore, when a flame retardant is added to these systems, it becomes increasingly difficult to do so because the stability of compatibility, film formation (fusion), blocking resistance, etc. are inhibited. In fact, with the mixed emulsion of polyurethane emulsion and styrene-butadiene copolymer emulsion and flame retardant according to the prior art, the viscosity increases significantly during mechanical foaming and solidifies into a tofu-like shape, or a large number of coarse bubbles are mixed in. However, the foam had no commercial value. The same applies to mixed emulsions of polyurethane emulsions and acrylic acid ester copolymer emulsions and flame retardants.Especially when molding at high expansion ratios and high coating thicknesses, bubbles may become coarse and disappear. Therefore, the product value of the foam was lost. Of course, it is not impossible to obtain something that has some commercial value with a low expansion ratio and low coating thickness (for example, about 1 mm thickness), but it is possible to significantly improve both the physical properties and foam moldability of the foam. It was not possible to do so, and the above requirements could not be met. [Means for Solving the Problems] The present inventors have developed a foam that has significantly improved physical properties such as strength and durability, flame retardancy, and foam moldability that allows it to be freely molded into a stable and industrially useful form. As a result of intensive research on the moldability of foams made from synthetic resin emulsions, it was found that when a mixture of a specific synthetic resin emulsion containing a specific substance and a flame retardant is used, the foam has excellent physical properties and flame retardancy. The present invention was achieved by discovering that foam moldability can be imparted. That is, the present invention provides a synthetic resin emulsion containing an ethylene oxide/propylene oxide random copolymer (D), that is, a mixed emulsion of (A) a polyurethane emulsion and (B) a conjugated diene and/or vinyl polymer emulsion, and a flame retardant (C). ) is mechanically foamed, the foamed solution is applied onto a base material or poured into a mold, and then heat treated. do. An object of the present invention is to provide a foam having excellent mechanical strength, flame retardance, heat resistance, cold resistance, light resistance, solvent resistance, and elasticity. Another object is to provide an emulsion with industrially useful foam moldability that allows the formation of such high-performance foams in stable and wide forms. Still another object is to provide a method for forming a flame-retardant foam having excellent physical properties and moldability from an emulsion that is a mixture of a polyurethane emulsion and another emulsion obtained by a completely different manufacturing method. It is in. [Function] According to the present invention, a flame retardant, a foaming aid, a viscosity modifier,
Adding a foam stabilizer, crosslinking agent, etc., mechanically blowing gas (mainly air) and stirring to foam, applying the foaming liquid onto a base material or pouring it into a mold, and then heat-treating. As a result, even under conditions such as high expansion ratio, high-speed processing (high-speed discharge, coating, and drying using a continuous mechanical foaming machine), and high coating thickness, it has a uniform porous shape with excellent surface smoothness, and has excellent mechanical strength and durability. This results in a flame-retardant foam with excellent properties. [Structure] The polyurethane emulsion used in the present invention is already known and can be produced by various methods. For example, by emulsifying a polyurethane solvent solution, or by reacting a polyhydroxy compound having a hydroxyl group at the end with an organic polyisocyanate in excess of the stoichiometric amount, as basically described in Japanese Patent Publication No. 33-1141, Then, a polyurethane emulsion obtained by emulsifying the obtained prepolymer in an aqueous dispersion medium using a surfactant and adding a chain extender to this to extend the chain of the prepolymer is also used. can do. Such polyhydroxy compounds usually have a molecular weight of 300 to 4000, preferably 600 to 3000,
Typical examples include polyether polyols and polyester polyols. Polyether polyols include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, trimethylene glycol, 1,3-butylene glycol,
Tetramethylene glycol, hexamethylene glycol, decamethylene glycol, glycerin,
Sorbitol, sucrose, aconitic acid, trimellitic acid, hemimellitic acid, phosphoric acid, ethylene diamine, propylene diamine, diethylene triamine, triisopropanolamine, pyrogallol, dihydrobenzoic acid, hydroxyphthalic acid,
Ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, using as an initiator one or more compounds having at least two active hydrogen atoms such as 1,2,3-propane trithiol, etc.
It is produced by addition polymerization of one or more monomers such as tetrahydrofuran and cyclohexylene by a conventional method. On the other hand, polyester polyols include, for example, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol,
At least two such as trimethylene glycol, 1,3-butylene glycol, tetramethylene glycol, hexamethylene glycol, decamethylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, etc.
one or more compounds having hydroxyl groups, malonic acid, maleic acid, succinic acid,
Adipic acid, tartaric acid, pimelic acid, sebacic acid,
One or more compounds having at least two carboxyl groups, such as oxalic acid, phthalic acid, terephthalic acid, hexahydrophthalic acid, aconitic acid, trimellitic acid, hemimellitic acid, etc., are condensed by a conventional method. Manufactured by polymerization. Polyhydroxy compounds such as polyether polyols and polyester polyols can be used alone or in combination of two or more, and further include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene Glycol, trimethylene glycol, 1,3-butylene glycol,
Tetramethylene glycol, hexamethylene glycol, decamethylene glycol, glycerin,
It can be used in admixture with low molecular weight polyols such as trimethylolpropane, pentaerythritol, sorbitol and the like. In addition, organic polyisocyanates include aliphatic,
Alicyclic or aromatic polyisocyanates, such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, m-phenylene diisocyanate, xylylene diisocyanate, tetramethylene diisocyanate, hexa Methylene diisocyanate, lysine diisocyanate, 1,4
-cyclohexylene diisocyanate, 4,4-
Dicyclohexyl diisocyanate, 3,3'-dimethyl-4,4-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,
4'-biphenyl diisocyanate-3,3'-3,
3'-dichloro-4,4'-biphenylene diisocyanate, 1,5-naphthalene diisocyanate,
Examples include 1,5-tetrahydronaphthalene diisocyanate and diphenyl-2,4,4-triisocyanate. Chain extenders are compounds having at least two active hydrogen atoms capable of reacting with isocyanate groups, such as ethylene glycol, tetramethylene glycol, hexamethylene glycol, diethylene glycol, monoethanol alumine, ethylene diamine, triethylene diamine, 1, 2-
propylene diamine, hexamethylene diamine,
N-ethanolethylenediamine, N,N'-diethanolethylenediamine, m-phenylenediamine, 2,4-tolylenediamine, bis-4-
Aminophenylmethane, 3,3'-dichloro-4,
4'-diaminodiphenylmethane, piperazine, 2
- Typical examples include glycols such as methylpiperazine, alkanolamines, and diamines, but also reaction products of 1 mole of alkylene diamine and 2 moles of acrylamide, and reaction products of 1 mole of alkylene diamine and 2 moles of acrylonitrile. Can be used. In the case of the present invention, the concentration of the polyurethane emulsion is not particularly limited, but in view of the economic efficiency during drying and the homogeneity of the foamed material, it is appropriate to range from 30 to 60% by weight, preferably from 40 to 50% by weight. The conjugated diene and/or vinyl polymer emulsion used in the present invention is a radical emulsion polymerization emulsion synthesized from one or more monomers selected from ethylenically unsaturated monomers and/or conjugated diene monomers. It is. It includes all mechanically foamable conjugated diene and/or vinyl polymer emulsions in the art. For example, acrylic ester polymers, styrene-butadiene polymers, acrylonitrile-butadiene polymers, methyl methacrylate-butadiene polymers, vinyl acetate polymers, ethylene-vinyl acetate polymers, and vinyl chloride polymers. Examples include emulsions such as The solid content concentration of these is 30 to 60% by weight, preferably 40%.
~60% by weight. Among these, particularly preferred are acrylonitrile-butadiene copolymers, styrene-butadiene copolymers, and acrylic acid ester copolymers containing carboxyl groups. Conjugated dienes used in the method of the invention include butadiene-1,3,2-methyl-butadiene-1,3,2-chlorobutadiene-1,3
However, in consideration of copolymerizability with other monomers and economic efficiency, it is preferable to use butadiene-1,3. Examples of the ethylenically unsaturated monomer in the method of the present invention include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, and acrylic acid. Alkyl acrylates and alkyl methacrylates exemplified by pentyl, pentyl methacrylate, hexyl acrylate, hexyl methacrylate, heptyl acrylate, heptyl methacrylate, octyl acrylate, octyl methacrylate, octadecyl acrylate, octadecyl methacrylate, etc. Ester; styrene, α-methylstyrene, vinyltoluene, chlorstyrene,
Ethylenically unsaturated aromatic monomers such as 2,4-dibromustyrene; unsaturated nitrites such as acrylonitrile and methacrylonitrile; acrylic acid, methacrylic acid, crotonic acid, maleic acid and its anhydride, fumar acids, itaconic acid, and unsaturated dicarboxylic monoalkyl esters, such as monomethyl maleate, monoester fumarate, mono-n-butyl itaconate, ethylenically unsaturated carboxylic acids; vinyl esters such as vinyl acetate, vinyl propionate, etc. ; vinylidene halides such as vinylidene chloride, vinylidene bromide, etc.; hydroxyalkyl esters of ethylenically unsaturated carboxylic acids such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, etc.; Glycidyl esters of ethylenically unsaturated carboxylic acids such as glycidyl acrylate and glycidyl methacrylate, and radical polymerization of acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide, N-butoxymethylacrylamide, diacetone acrylamide, etc. Examples include monomers such as When mixing the polyurethane emulsion (A) and the conjugated diene and/or vinyl polymer emulsion (B), the mixing ratio is (A)/(B) = 80/20 to 10/90.
(solid content weight ratio) is preferable. If the polyurethane emulsion is less than 10% by weight, a foam with high strength and high durability, which is one of the objectives of the present invention, cannot be obtained, and if the polyurethane emulsion is more than 80% by weight, The wide foam moldability, which is one of the objectives, is impaired, and the objective of the invention cannot be accomplished. However, this does not preclude deviating from the above range in order to achieve other objectives by sacrificing a part of the present invention. The resin concentration in the mixed emulsion is 40% considering economic efficiency and higher foam moldability.
~60% by weight, especially 45-55% by weight is preferred. It should be noted that this does not hinder pH adjustment or particle size adjustment prior to mixing the emulsion, and may be preferable in some cases. The ethylene oxide/propylene oxide copolymer (D) used in the present invention includes methyl alcohol, ethyl alcohol, propyl alcohol,
It can be produced by randomly adding ethylene oxide and propylene oxide at a molar ratio of 95 to 50:5 to 50 using monoalcohols such as butyl alcohol, polyalcohols such as ethylene glycol and glycerin, and polyamines as starting materials.
Although not particularly limited to this, the composition contains 50 to 95 mol% of ethylene oxide, preferably 70 to 90 mol%, and 5 to 50 mol% of propylene oxide, preferably 10 to 30 mol%, at 38°C. The viscosity is
3000~50000cps is preferable. A typical example is Tergitol XD (product of UCC). The amount of the ethylene oxide/propylene oxide random copolymer is 0.01 to 10 parts by weight, preferably 0.05 to 10 parts by weight, based on 100 parts by weight of the synthetic resin emulsion.
It is 5 parts by weight. There is no particular restriction on the timing of adding the ethylene oxide/propylene oxide random copolymer, but it is preferable to add it to the synthetic resin emulsion in advance and to homogenize it prior to adding the additives. It is particularly preferable to use it as part or all of an emulsifier during emulsion polymerization of both or one of a polyurethane emulsion and a conjugated diene and/or vinyl polymer emulsion. The effects of the presence of ethylene oxide/propylene oxide random copolymer (abbreviated as random copolymer) that characterize the present invention will be described below. This random copolymer improves the mixing stability when a polyurethane emulsion is mixed with a conjugated diene and/or vinyl polymer emulsion which is different in terms of resin properties and water dispersion form properties. Incidentally, as an additional effect, by using it as part of an emulsifier during polymerization, it is useful for stably producing a high concentration emulsion that is advantageous for foam molding. In addition, random copolymers enhance the retention of blown air, making it possible to achieve high expansion ratios (for example, around 6 times), and also have the effect of improving mechanical stability, making them suitable for high-speed processing using continuous mechanical foaming machines. Improve. Moreover, random copolymers are
Since it helps solidify quickly at temperatures (100 to 180°C), it prevents the volume from decreasing due to heat treatment and enables a high coating thickness (for example, around 5 mm). It should be noted that the behavior is completely different from that of ethylene oxide/propylene oxide block copolymers, which are obtained from similar components and are also commonly used as emulsifiers. Conventionally used ethylene oxide/propylene oxide block copolymers, such as Pluronic F-88 (manufactured by Asahi Denka Kogyo Co., Ltd., ethylene oxide/propylene oxide = 80/20 weight ratio, solid molecular weight approximately 12,000), It is poor in air retention in the foaming liquid during foaming and mechanical stability of the foaming liquid, and also tends to reduce volume and coarsen bubbles during heat treatment, making it impossible to stably form a good foam. It is. Based on the above-mentioned effects of random copolymers, it is possible to mix and use polyurethane emulsions with conjugated diene and/or vinyl polymer emulsions, and the compatibility with flame retardants becomes easy.
The foam obtained by the present invention can exhibit excellent physical properties such as mechanical strength, heat resistance, cold resistance, light resistance, solvent resistance, rebound resilience, and flame retardance that cannot be obtained by conventional methods. The flame retardant (C) used in the present invention is not particularly limited, but preferably one that does not reduce the performance of the synthetic resin emulsion or base material, and one that does not reduce the foamability and moldability in the foaming process. Also, those that do not reduce the heat resistance and light resistance of processed products, and those that are less toxic and corrosive, such as triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, tris (halopropyl) phosphate, tris (haloethyl) Phosphate esters such as phosphate, chlorinated paraffin, chlorinated polyethylene perchloro-pentacyclodecane, hexabromobenzene, decabromodiphenyl oxide, tetrabromobisphenol A,
Examples include halogen-containing organic compounds such as hexabromocyclododecane, and inorganic compounds such as ammonium bromide, antimony trioxide, aluminum hydroxide, and barium antimonate metaborate, either singly or in a mixture of two or more. The mixing ratio of the flame retardant and the synthetic resin emulsion is not particularly limited, but preferably flame retardant/synthetic resin emulsion = 10/90 to 70/
A solids weight ratio of 30 is desirable. Foaming aids added to synthetic resin emulsions, including random copolymers, include sodium laurate, coconut oil soap, sodium myristate, ammonium stearate, sodium palmitate, sodium oleate, sodium higher alcohol sulfate, higher Sodium fatty acid amidoalkyl sulfonate, saponin, gelatin, or casein are used. As the perfluoroalkyl group having 1 to 20 carbon atoms, a fluorine-containing surfactant having a fluoroalkyl group is also used. Viscosity modifiers include casein, alginate,
Gum arabic, bentonite, clay, carboxylated methyl cellulose, polyvinyl alcohol,
Polyvinylpyrrolidone copolymers, polyethylene oxide polymers, polyacrylic acid emulsions, etc. are used. The amount of these additions is usually 0.1~
5 parts, preferably 0.5 to 3 parts. Viscosity is 1000
~15000cps is appropriate. As the crosslinking agent, water-soluble melamine-formaldehyde resin, water-soluble urea-formaldehyde resin, water-soluble or water-dispersible epoxy resin, aziridine compound, etc. are used. Addition of silicone oil is effective in order to fully reflect the elastic properties of the foam, which are similar to those of polyurethane resins. Examples include dimethyl silicone oil, methylphenyl silicone oil, amino-modified silicone oil, and polyether-modified silicone oil. The amount added is 0.1 to 100 parts by weight of the emulsion.
3 parts by weight are used. Pre-emulsion silicone oil may also be used. In addition, colorants, fillers, anti-aging agents, anti-fog agents, etc. may be used within the range that does not impair the purpose of the present invention. In this manner, the synthetic resin emulsion containing the ethylene oxide/propylene oxide random copolymer and having an appropriate viscosity is then foamed using a known method for rubber latex, thereby converting it into a synthetic resin emulsion having uniform, fine cells. In this case, mechanical foaming is the most common method, but the type of foaming machine is not particularly limited, and those generally used for foaming rubber latex can be used. An example is as follows. A synthetic resin emulsion containing a random copolymer and a flame retardant, adjusted to an appropriate viscosity, and further blended with a foaming aid, viscosity modifier, foam stabilizer, crosslinking agent, etc. as required,
It is fed into a foaming machine by a gear pump or the like. Meanwhile, gas (usually air) is fed into the foaming machine by a compressor or the like. Each flow rate is controlled by a gauge. The emulsion and gas fed into the foaming machine are mixed there, and the gas fed by the rotating cylinder is finely divided and dispersed into the synthetic resin emulsion.
The thus foamed synthetic resin emulsion comes out of the foaming machine. The amount of gas mixed in is related to the density of the synthetic resin emulsion foam obtained by drying (ratio of gas to synthetic resin emulsion)
This is done by controlling the amount of gas injected, and the size of the bubbles is controlled by the viscosity of the synthetic resin emulsion and the rotational speed of the cylinder. (Experimentally, a hand mixer is sufficient for foaming the synthetic resin emulsion.)
In this case, the expansion ratio is generally 1.5 to 6. The synthetic resin emulsion thus foamed is poured into a mold or cast onto a substrate and dried. In this case, a doctor knife is generally used to coat the substrate to a uniform thickness. The base materials include fiber fabrics, fiber knitted fabrics, textile products such as raised fabrics, flocked fabrics, non-woven fabrics, paper, polyvinyl chloride sheets, leather sheets, release paper, films with release properties such as polypropylene and polyester, and glass. Examples include plates, metal plates, and the like. By drying the applied synthetic resin emulsion containing bubbles, the dispersion medium (water) is removed, and a foamy substance having uniform and fine bubbles is obtained. Drying temperature is 60-160℃ preferably 100-140℃
It is. When the emulsion is cured by heat treatment, the drying is followed by heat treatment. [Effects of the Invention] The foam according to the present invention can be formed on various substrates and used for various purposes. For example, synthetic leather for bags, clothing, shoes, etc., artificial leather, other fake leather-like coated cloth, car seat backing, carpet (backing), kotatsu mat, entryway, etc.
Includes bath mats, sponge sheets or other molded products, methods of not only forming a foam, but also of forming a foam and also serving as an adhesive layer, and methods of applying embossing after forming a foam. It is possible. For example, a foam layer is formed between two base materials (2), and the base materials are fixed to each other at the same time, or a foam is formed on the top of one base material, and at the same time, the foam layer is formed between the base materials (2) and another base material (2). These include foam flocking, which has a fixed base material, and foam flocking, in which the foam also serves as a binder for the pile. In addition, the formed foam is subjected to post-emboss processing to give a secondarily uneven pattern. This is an example of another feature of the foam of the present invention, which is the good adhesion of the cell walls under constant heat/pressure, and the high elasticity of the remaining foam with a high expansion ratio. The above examples of applications and uses are not limiting, but merely examples that take advantage of the wide range of industrially advantageous foam-forming features of the present invention. Next, the present invention will be specifically explained with reference to Examples. Incidentally, parts and percentages shown in the text are parts by weight and percentages by weight unless otherwise specified. Reference example 1 Polyoxypropylene glycol (average molecular weight
1000) and 175 parts of tolylene diisocyanate were mixed and reacted at 80°C for 2 hours to produce a prepolymer with an NCO equivalent of 712. To this was added 270 parts of toluene to form a homogeneous solution. 140 parts of this prepolymer solution was placed in a mixer running at 12,000 revolutions per minute, and an aqueous solution containing 6 parts of polyoxyethylene nonylphenol ether with an added mole of ethylene oxide of 25 was added.
Add 70 parts of 1,6-hexamethylenediamine and stir for 3 minutes, and while gently stirring the resulting emulsion, add a chain extender aqueous solution of 8.2 parts of 1,6-hexamethylenediamine dissolved in 30 parts of water for 2 minutes. and dripped it. After dropping, stirring was continued slowly for 2 hours to obtain a stable polyurethane emulsion (A-1). Solid content concentration 46%,
The viscosity was 850 centipoise. Reference example 2 Polyester diol obtained from diethylene glycol and adipic acid (average molecular weight 1050) 525
106 parts of an aqueous solution containing 6 parts of ethylene oxide-propylene oxide block copolymer (Pluronik F-88: manufactured by Asahi Denka Kogyo) were added to 210 parts of a prepolymer solution obtained from 222 parts of isophorone diisocyanate and 300 parts of toluene to make an emulsion. To this was added 36 parts of an aqueous solution containing 6 parts of piperazine, and the reaction was carried out in the same manner as in Reference Example 1 to obtain a stable polyurethane emulsion (A-2). The solid concentration was 46% and the viscosity was 900 centipoise. Reference Example 3 A monomer consisting of 60 parts of butadiene, 30 parts of acrylonitrile, and 10 parts of methacrylic acid was mixed with 0.5 parts of ethylene oxide-propylene oxide random copolymer (Targitol XD trademark), 2 parts of sodium alkylbenzenesulfonate, and sodium pyrophosphate.
0.5 parts, ammonium ethylenediaminetetraacetate 0.1
part, 0.3 part of terciary decyl mercaptan,
Polymerization was carried out at 60° C. for 12 hours in the presence of 0.3 parts of potassium persulfate and 120 parts of ion-exchanged water in an autoclave equipped with a stirrer. Next, potassium hydroxide was added to adjust the pH to 8.5, and unreacted monomers were removed and concentrated to create a stable acrylonitrile-butadiene copolymer emulsion (B-1) containing an ethylene oxide-propylene oxide random copolymer. ) was obtained. The solid concentration was 55% and the viscosity was 100 centipoise. For values without using Tergitol XD, a stable emulsion (B-2) was obtained in the same manner as above.
The solid content was 55% and the viscosity was 2000 centipoise. Reference example 4 70 parts of ethyl acrylate, 25 parts of methyl methacrylate
1 part, 5 parts of acrylic acid, 3 parts of sodium alkylbenzenesulfonate, and potassium persulfate.
Polymerization was carried out at 60° C. for 4 hours in the presence of 0.3 parts and 150 parts of ion-exchanged water. Next, stripping was performed to obtain a stable emulsion (B-3).
The solid concentration was 60% and the viscosity was 1500 centipoise. Reference Example 5 478 g of hexabromocyclododecane (hereinafter referred to as HBCD), 20 g of lignin sulfonate, 2 g of carboxyl methylcellulose, and 500 g of water were mixed, and an emulsifier was used to prepare a stable flame retardant aqueous dispersion (C-1) with a concentration of 50%. ) was obtained. Reference Example 6 The same procedure was used as in Reference Example 5 except that decabromodiphenyl ether/antimony pentoxide = 1/1 (weight ratio) was used instead of HBCD in Reference Example 5, but the concentration was 70.
% flame retardant (C-2) was obtained. Reference example 7 Tris(-2-chloropropyl)phosphate
Dissolve 23 parts of polyoxyethylene nonylphenol ether with 12 moles of ethylene oxide added in 450 parts, add water using a conventional method and phase inversion emulsify to give a concentration of 50.
% milky white emulsion (C-3) was obtained. Reference example 8

Add 100 parts of tris(-2-chloroethyl) phosphate to 350 parts of a polyphosphonate compound having an average molecular weight of 5000 represented by the formula, and dissolve 20 parts of polyoxyethylene nonylphenol ether having an added mole of ethylene oxide of 20. Add water to emulsify the phase and increase the concentration.
A 50% milky white emulsion (C-4) was obtained. Example 1 50 parts of polyurethane emulsion (A-1), 50 parts of acrylonitrile-butadiene copolymer emulsion (B-2), 40 parts of flame retardant (C-1) and 5 parts of a 10% aqueous solution of Tergitol XD An aqueous solution of carboxymethylcellulose was added to the mixed emulsion to adjust the viscosity to 8000 centipoise, and then 1 part of silicone oil and 4 parts of glycerol triglycidyl ether were added and mixed uniformly.
This mixture was foamed using a continuous mechanical foaming machine (manufactured by Suga Kikai), applied onto cotton broadcloth and polyester napkin, and heat-treated at 120°C for 8 minutes to obtain a foamed sheet with uniform fine bubbles and a smooth surface. This foamed sheet was found to be excellent in abrasion resistance, light resistance, etc.
Table 1 shows the physical properties. Examples 2 to 4 Flame retardant (C-1) was replaced with 40 parts of flame retardant (C-1).
2) A foamed sheet was obtained in the same manner as in Example 1 except that the amount was 40 parts (Example 2), and flame retardant (C-1) 40 parts
A foamed sheet was obtained in the same manner as in Example 1 except that 40 parts of the flame retardant (C-3) was used instead of 40 parts (Example 3),
Also, instead of flame retardant (C-1), flame retardant (C-4)40
A foamed sheet was obtained in the same manner as in Example 1, except that the foamed sheet was made into a foamed sheet. (Example 4). The physical properties are shown in Table-1. Comparative Example 1 A foamed sheet was obtained in the same manner as in Example 1 except that the flame retardant (C-1) was removed. The physical properties are shown in Table-1. Comparative Examples 2 and 3 A foamed sheet was obtained in the same manner as in Example 2, except that the polyurethane emulsion (A-1) and Tergitol XD were removed (Comparative Example 2). A foamed sheet was also obtained in the same manner as in Example 3, except that polyurethane emulsion (A-1) and Tergitol XD were removed (Comparative Example 3). The physical properties are shown in Table-1. Comparative Example 4 A foamed sheet was obtained in the same manner as Comparative Example 2 except that the flame retardant (C-2) was removed. The physical properties are shown in Table-1. Example 5 A foamed sheet was prepared in the same manner as in Example 1 using 50 parts of polyurethane emulsion (A-1), 50 parts of acrylonitrile-butadiene copolymer emulsion (B-1), and 40 parts of flame retardant (C-2). Obtained. The physical properties are shown in Table-1. Example 6 50 parts of polyurethane emulsion (A-2), 50 parts of acrylic ester emulsion (B-3)
A foamed sheet was obtained in the same manner as in Example 1 except that the flame retardant (C-2) was used. The physical properties are shown in Table-1. Comparative Example 5 A foamed sheet was obtained in the same manner as in Example 5 except that the flame retardant (C-2) was omitted. The physical properties are shown in Table-1. Comparative Example 6 A foamed sheet was obtained in the same manner as in Example 6 except that the flame retardant (C-2) was omitted. The physical properties are shown in Table-1. Comparative Example 7 A foamed sheet was obtained in the same manner as in Example 5 except that the vinyl copolymer emulsion (B-1) was removed.
The physical properties are shown in Table-1. Comparative Example 8 A foamed sheet was obtained in the same manner as in Example 5, except that the vinyl copolymer emulsion (B-1) and the random copolymer D were removed. The physical properties are shown in Table-1.

[Table] About Table-1 A is the polyurethane aqueous dispersion A-1 and A-2 obtained in Reference Example 1, and B is the conjugated diene and/or vinyl polymer emulsion obtained in Reference Examples 2 and 3. B-1, B-2, B-
3, and C is the flame retardant C shown above and in Table-1.
-1 to C-11, D represents an ethylene oxide-propylene oxide random copolymer, and A/B/C are their solid content weight ratios. In the table, (a) shows the case where 1 mm of the 2x foaming solution is applied onto the cotton broadcloth, (b) shows the case where the 5x foaming solution is applied 5mm onto the cotton broadcloth, and (c) shows the case where the 5x foaming solution is applied to the polyester fabric. When 5mm is applied to the back side of the blanket. The "state of the foaming liquid" was determined by observing and comparing the state of the bubbles when the mechanical foaming solution was received in a 500 c.c. beaker and the state of the bubbles when about 1 cm of the upper layer was scraped off after leaving it for 5 minutes. ◎: Bubbles are fine and uniform with no change. ○: The bubbles were fine and uniform, but slightly coarsened. △:
The bubbles were somewhat non-uniform and quite coarse. ×: Contains many coarse bubbles and is significantly non-uniform. The "state of the foam" was determined by observing the cell state and surface smoothness of the cross section of the foam after coating and drying. ◎: The bubbles are fine and uniform, and the surface is smooth. ○: There are coarse bubbles and the surface smoothness is slightly poor. △: The bubbles are rough and there are some cracks. ×: There are cracks. "Abrasion strength" was measured using a Gakushin type abrasion tester (flat method, load 500g, number of times until breakage). ◎: 500 times or more Good 〇: 499-200 times △: 199
~50 times: 49 times or less. Light resistance was determined by examining the degree of discoloration and abrasion strength after 20 hours of irradiation with a fade meter. Degree of discoloration ◎: No discoloration △: Slight yellowing ×:
Significant discoloration (yellowing). "Flame retardancy" was determined by measuring the burning rate in accordance with the MVSS-302 standard. Unit: cm/min. N: Fire extinguished by the starting line n; Burning rate: 5
Extinguished within 1 minute at less than cm/min. "Texture" was examined by hand touch.

Claims (1)

[Claims] 1. A mixture of (A) a polyurethane emulsion, (B) a conjugated diene and/or vinyl polymer emulsion, and (D) a synthetic resin emulsion containing an ethylene oxide/propylene oxide random copolymer, and (C) a flame retardant. A method of forming a flame-retardant foam, comprising mechanically foaming, coating the foaming liquid onto a substrate or pouring it into a mold, and then heat treating.