JPH0444034B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a dust control mat with excellent washing resistance. Prior Art In tufted carpets, which are currently a typical carpet, piles of nylon, acrylic, vinylon, etc. are implanted in the primary base fabric, and a backing treatment is applied to prevent the piles from falling off. has been done. For this lining treatment, an aqueous dispersion composition is used, which is prepared by adding fillers, dispersants, anti-viscosity agents, etc. as necessary to an aqueous dispersion of a high molecular weight polymer such as synthetic rubber latex. In recent years, there has been a strong demand for such carpets to have washing resistance, and in particular, so-called dust control mats are required to prevent dimensional changes in the mats, such as small shrinkage and curling phenomenon, even after multiple washings. It is required to have severe washing resistance, such as no pile or falling off of the backing resin. In order to ensure such washing resistance, various aqueous dispersion compositions have already been proposed. For example, JP-A-59-15465 describes an aqueous dispersion composition comprising a styrene-butadiene copolymer rubber latex mixed with an epoxy compound and a compound having an aziridine ring. Compositions made by blending rubber latex with a thermosetting resin such as methylol melamine or a vulcanizing agent singly or in combination are also known; There is still a need for improvement in regards to the falling off etc. Problems to be Solved by the Invention As a result of intensive research to solve the above-mentioned problems in conventional dust control mats, the present inventors have developed an aqueous dispersion of a high molecular weight polymer as a composition for forming the backing resin. By using a solution containing blocked polyisocyanate, it has far superior washing resistance.
The present invention was developed based on the discovery that it is possible to obtain a dust control mat that can meet the above-mentioned severe requirements. Means for Solving the Problems The dust control mat according to the present invention contains 0.5 to 30 parts by weight of blocked polyisocyanate per 100 parts by weight of solid content of an aqueous dispersion of a polymer having carboxyl groups and/or hydroxyl groups in the molecule. The method is characterized in that a composition containing the following is applied to the back side of a base fabric in which piles are implanted, dried, and then heated to form a backing resin. Examples of the aqueous dispersion of the polymer used in the present invention include styrene-butadiene rubber (SBR) latex, methyl methacrylate-butadiene rubber (MBR) latex, acrylonitrile-butadiene rubber (NBR) latex,
Conventionally known polymer latexes such as natural rubber (NR) latex, vinyl chloride polymer latex, methyl methacrylate-styrene-butadiene rubber (MSBR) latex, ethylene-vinyl acetate latex, and acrylic latex. is used. The high molecular weight polymers in these latexes may have functional groups such as carboxyl groups, hydroxyl groups, amide groups, glycidyl groups, and sulfonic acid groups. In particular, in the present invention,
Latexes of high molecular weight polymers having carboxyl groups and/or hydroxyl groups are preferably used. The manner in which these functional groups are included in the high molecular weight polymer in the latex is not limited in any way, but typically, the above-mentioned functional groups are included in the molecule together with the monomer components that constitute the main polymer. It can be obtained by copolymerizing monomer components in the chain. For example, to introduce carboxyl groups into latex, as monomer components in the above copolymerization,
If ethylenically unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, ethylenically unsaturated dicarboxylic acids such as fumaric acid, maleic acid, and itaconic acid, or half esters of these ethylenically unsaturated dicarboxylic acids are used, good. In addition, in order to introduce a hydroxyl group into the latex, as a monomer component in the above copolymerization, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, N-methylol (meth)acrylamide or the like may be used. Furthermore, the polymerizable polymer compounds having these functional groups obtained in this way can be copolymerized, or the polymer compounds having these functional groups can be used as a protective colloid for the polymer during the polymerization reaction. Alternatively, it can be added after the polymerization reaction. The blocked polyisocyanate used in the present invention is an addition reaction to the free isocyanate groups of the polyisocyanate to inactivate it, but it is easily dissociated by heating and/or a catalyst to form free isocyanate groups again. Refers to an addition reaction product between polyisocyanate and a compound (hereinafter referred to as a blocking agent) that forms a bond that regenerates a polyisocyanate having a group. Such blocked polyisocyanates are already known and are described, for example, in JP-A-60-203685. As the polyisocyanate for the above-mentioned blocked polyisocyanate compound, any conventionally known polyisocyanate can be used. Therefore, such polyisocyanates include, for example, ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, methyl 2,6-diisocyanatocaproate, etc. aliphatic diisocyanate, 3-isocyanatomethyl-3,5,
5-trimethylcyclohexane, 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane, methylcyclohexane-2,4- or 2,
6-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3- or 1,
Alicyclic diisocyanates such as 4-diisocyanatocyclohexane, aromatic diisocyanates such as m- or p-phenylene diisocyanate, diphenylmethane-4,4'-diisocyanate, 2,4- or 2,6-tolylene diisocyanate, 1 ，
3'- or -1,4-bis(isocyanatomethyl)
Mention may be made of diisocyanates such as benzene, araliphatic diisocyanates such as 1,3- or 1,4-bis(α-isocyanatoisopropyl)benzene. In addition, as the triisocyanate, triphenylmethane-4,4,4″-triisocyanate,
1,3,5-triisocyanatobenzene, 1,
Examples include 3,5-tris(isocyanatomethyl)cyclohexane, 1,3,5-tris(isocyanatomethyl)benzene, and 2-isocyanatoethyl 2,6-diisocyanatocaproate. Further, as the polyisocyanate that can be used in the present invention, for example, polymerized polyisocyanate such as dimer or trimer of diisocyanate, polymethylene polyphenylene polyisocyanate, an excess of the above isocyanate compound, and, for example, ethylene glycol, propylene glycol. , dipropylene glycol, diethylene glycol, triethylene glycol, 2,2,4-trimethyl-1,
3-pentanediol, neopentyl glycol, hexanediol, cyclohexanedimethanol, cyclohexanediol, hydrogenated bisphenol A, xylylene glycol, glycerin, trimethylolethane, trimethylolpropane,
Active hydrogen-containing low molecular weight compounds such as hexanetriol, pentaerythritol, sorbitol, sorbitol, sucrose, castor oil, ethylenediamine, hexamethylenediamine, ethanolamine, diethanolamine, triethanolamine, water, ammonia, urea, or various polyether polyols. , polyisocyanates obtained by reacting with active hydrogen-containing high molecular weight compounds such as polyester polyols, polyurethane polyols, acrylic polyols, and epoxy polyols,
Alternatively, mention may be made of these allophanated polyisocyanates, biuretted polyisocyanates, and the like. The above isocyanate compound may be used alone or in combination.
Used as a mixture of more than one species. As the blocking agent, any conventionally known blocking agent can be used. Examples of such blocking agents include phenolic blocking agents such as phenol, cresol, p-nonylphenol, and hydroxybenzoic acid ester;
- Lactam blocking agents such as caprolactam and γ-butyrolactam, active methylene blocking agents such as diethyl malonate, methyl acetoacetate, and acetylacetone, ethanol, isopropyl alcohol, t-butyl alcohol, lauryl alcohol, and ethylene glycol monoethyl ether. ,
Alcohol blocking agents such as benzyl alcohol, glycolic acid, glycolic ester, lactic acid, lactic ester, diacetone alcohol, ethylene chlorohydrin, butyl mercaptan, octyl mercaptan, t-dodecyl mercaptan, 2
-Mercapcan-based blocking agents such as mercaptobenzothiazole and thiophenol; acid amide-based blocking agents such as acetanilide, acetamide, acrylamide, and benzamide; succinimide;
Imide-based blocking agents such as phthalimide, amine-based blocking agents such as diphenylamine, carbazole, aniline, and dibutylamine, imidazole-based blocking agents such as imidazole and 2-ethylimidazole, and urea-based blocking agents such as urea, thiourea, and ethylenethiourea. Blocking agents, carbamate ester blocking agents such as 2-oxazolidone and phenyl N-phenylcarbamate, formaldoxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, diacetyl monoxime, cyclohexanone oxime, benzophenone oxime, etc. Examples include oxime-based blocking agents, and sulfite-based blocking agents such as sodium hydrogen sulfite and potassium hydrogen sulfite.
These blocking agents may be used alone or in combination of two or more types, but in the present invention, the oxime-based blocking agent is particularly suitable for
This is preferable from the viewpoint of safety and the like. As mentioned above, the blocked polyisocyanate can be obtained by reacting a polyisocyanate and a blocking agent in a conventional manner. This reaction can be carried out in a solvent that does not contain active hydrogen or in the absence of a solvent. Examples of solvents without active hydrogen include esters such as ethyl acetate, butyl acetate, cellosolve acetate, carbitol acetate, dimethyl ester of dibasic acids, ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, toluene, Aromatic solvents such as xylene, Solbetsuso #100, and Solbetsuso #150 can be mentioned. Further, when a sulfite-based blocking agent is used as the blocking agent, it is often preferable to use water as the solvent. As mentioned above, the blocking reaction of polyisocyanate may be carried out by a conventional method, but more specifically, for example, a reaction with a polyisocyanate blocking agent may be carried out.
A method of reacting the polyisocyanate and the blocking agent at an NCO/blocking agent (equivalence ratio) of about 0.9 to 1.1, preferably about 0.95 to 1.0, and a method of reacting the polyisocyanate and the blocking agent at an NCO/blocking agent (equivalence ratio) of about 1.1 to 3.0, preferably about 1.1 to 3.0. is about 1.2 to 2.0, and then reacted with the above-mentioned active hydrogen-containing low molecular weight compound and/or active hydrogen-containing high molecular weight compound, polyisocyanate and active hydrogen containing low molecular weight compound and/or active hydrogen containing compound The NCO/active hydrogen (equivalent ratio) of the high molecular weight compound is about 1.5 to 10.0, preferably about 2.0 to
Examples include a method in which the polyisocyanate is reacted as 7.0, the polyisocyanate is removed if necessary, and then the blocking agent is reacted with the polyisocyanate. However, it is not limited to these. In addition, during the blocking reaction of polyisocyanate, for example, the third
Conventionally known catalysts such as grade amines and organometallic compounds may also be used. The thus obtained blocked polyisocyanate is usually preferably blended into the aqueous dispersion of the high molecular weight polymer as an aqueous mixture such as an aqueous emulsion, an aqueous dispersion or an aqueous solution. In this way, in order to form the blocked polyisocyanate into an aqueous mixture, any conventionally known method can be used. For example, the blocked polyisocyanate is mechanically made into fine particles and dispersed in water; A method of stabilizing the dispersion using surfactants, protective colloids, dispersants, etc., as necessary;
A method of emulsifying using a surfactant, a protective colloid, etc., a method of introducing a salt-forming group into a part of the blocked polyisocyanate to form a salt, or a method of adding a hydrophilic group to the blocked polyisocyanate itself. Examples include a method in which the polyisocyanate is introduced to make it self-emulsifying or water-soluble, and a method in which a hydrophilic blocking agent is used to impart self-emulsifying property or water-solubility to the resulting blocked polyisocyanate. Furthermore, a combination of two or more of these methods is also possible. When a solvent is used in producing blocked polyisocyanate, it may be treated by emulsifying, dispersing, dissolving, etc. in water while containing the solvent, or it may be treated after removing the solvent in advance. Good too. If the product is treated by emulsifying, dispersing, dissolving, etc. in water while still containing the solvent, it is possible to remove the solvent by evaporation, liquid separation, etc. In addition, a tertiary material is added to the blocked polyisocyanate.
It is also possible to prepare an aqueous mixture by adding conventionally known isocyanate reaction catalysts such as grade amines and organometallic compounds, and dissociation catalysts for blocked polyisocyanates. In the composition used in the present invention, the blending ratio of the aqueous dispersion of the high molecular weight polymer and the blocked polyisocyanate depends on the performance required of the backing resin formed from the composition and the properties of each component. However, the solid content of the aqueous dispersion of the polymer is usually
The amount of blocked polyisocyanate to be blended is in the range of 0.5 to 30 parts by weight based on solid content per 100 parts by weight. If the amount of blocked polyisocyanate in the composition is less than 0.5 parts by weight, the wash resistance as described above will not be sufficient, while if it is more than 30 parts by weight, the composition will not have sufficient wash resistance. The backing resin becomes hard and brittle, making it easy for the resin to crack or fall off. Furthermore, since blocked polyisocyanates are usually more expensive than aqueous dispersions of high molecular weight polymers, it is disadvantageous from an economic point of view to blend them in an amount greater than that which provides the required performance. . From the above, the amount of the blocked polyisocyanate in the composition is preferably in the range of 1 to 20 parts by weight. To obtain a mixture of a polymer dispersion and a blocked polyisocyanate, it is usually sufficient to mix them as they are, but if necessary, surfactants, dispersants, thickeners may be added, or pH It is also possible to make a more stable mixture by adjustment or the like. In the present invention, the blocked polyisocyanate can be partially substituted with an epoxy compound. Epoxy compounds that can be preferably used in the present invention include bisphenol type, resorcinol type, and alicyclic epoxy resins having an average of two or more epoxy groups per molecule, as well as ethylene glycol, propylene glycol, glycerin, hexanetriol, Examples include reaction products of epichlorohydrin and aliphatic polyhydric alcohols such as trimethylolpropane and polyethylene glycol. These epoxy compounds may be water-soluble or water-insoluble, and depending on their solubility in water, they are blended into the aqueous dispersion of the polymer as an aqueous solution or emulsified. . When an epoxy compound is blended with a blocked polyisocyanate into an aqueous dispersion of a high molecular weight polymer, although the pot life is shortened, shrinkage and curling of the dust control mat after washing and shedding of the resin are small, and A backing resin with improved wash resistance is formed. However, blending a large amount of an epoxy compound will drastically shorten the pot life, so from the viewpoint of the balance between performance and usability, in the present invention, the blending amount of the epoxy compound is The solid content is 10 parts by weight or less per 100 parts by weight of the solid content of the liquid. The composition for forming the backing resin used in the present invention may contain conventional blending agents, such as fillers, dispersants, antioxidants, thickeners, colorants, etc., in addition to the above-mentioned components, as well as blocking resin compositions. It may contain a polyisocyanate dissociation catalyst, an isocyanate reaction catalyst, and the like. Fillers typically include, for example,
Calcium carbonate, aluminum hydroxide, clay,
Talc etc. are used. The blending amount is based on 100 parts by weight of the solid content of the aqueous dispersion of the high molecular weight polymer.
Usually, it is 100 parts by weight or less. When blending in a large amount exceeding 100 parts by weight, it is not preferable because there is a risk that the washing resistance will decrease. The dust control mat according to the present invention is produced by applying the above-described composition for forming the backing resin to the back side of the base fabric in which the pile is embedded, drying it, heating it to a temperature of 110 to 200°C, and applying the composition to form the backing resin. can be obtained by forming Effects of the Invention According to the method of the present invention, the composition used for forming the backing resin is composed of a blocked polyisocyanate mixed with an aqueous dispersion of a high molecular weight polymer, and thus the formed backing resin is made of a high molecular weight polymer. It has a cross-linked three-dimensional structure of polymer and polyurethane,
Because of their toughness, dust control mats with such backing resins have the harsh wash resistance described above. Furthermore, the aqueous composition for forming the backing resin used in the present invention has a significantly longer pot life than conventional compositions of the same type, even after a long period of time has passed from the manufacture of the composition to its use. No problems arise. The present invention will be described below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples in any way. Example Acrylonitrile-butadiene rubber (NBR)
Blocked polyisocyanate and
A composition was prepared by adding an epoxy resin in some cases, adding heavy calcium carbonate, and adjusting the viscosity to 10,000±1,000 cps with carboxymethyl cellulose. The above composition was uniformly applied at a rate of 1.0 kg/m ² to the back side of a polyester base fabric in which a pile made of polyamide was embedded, and pre-dried at 120°C for 15 minutes.
Then, it was dried with hot air at 150°C for 10 minutes. The thus obtained dust control mat was washed in a washing machine with a bath ratio of 1:30 and a detergent concentration of 0.14%.
One cycle is washing at 40℃ for 7 minutes, rinsing with cold water overflow for 10 minutes, and completely drying at 100℃.
After 30 cycles, the dimensional change of the pine was measured, and the back surface of the pine and the state of curling were observed. The results are shown in Table 1. The dust control mats of Comparative Examples 1 and 2 obtained using compositions in which only fillers and thickeners were added to latex were as follows:
Significant shrinkage after washing. In contrast, as seen in Examples 1-4 and 7-11, the dust control mats obtained according to the present invention
Not only is the shrinkage rate extremely low, but there is almost no curling.

【table】

[Table] It is clear that no resin was observed, and that the resin did not fall off, indicating that it had excellent washing resistance. Furthermore, as seen in Examples 5 and 6, it is clear that the above-mentioned washing resistance was comprehensively improved in the compositions further containing an epoxy resin.

Claims (1)

[Claims] 1 Blocked polyisocyanate 0.5 to 30 parts per 100 parts by weight of solid content of an aqueous dispersion of a polymer having carboxyl groups and/or hydroxyl groups in the molecule
1. A dust control mat characterized in that a composition containing a weight part of the composition is applied to the back side of a base fabric in which piles are implanted, dried, and then heated to form a backing resin.