US2915418A - Non-woven fibrous products - Google Patents

Description

United States Patent M NON-WOVEN FIBROUS PRODUCTS Robert E. Wolfrom, Jenkintown, Pa., assignor to Rohm & Haas Company, Philadelphia, Pa., a corporation of Delaware No Drawing. Application November 21, 1956 Serial No. 623,529

19 Claims. (Cl. 117-140) This invention relates to bonded fibrous or filamentous products having a carded fiber structure or comprising fibrous mats in which the fibers or filaments are distributed haphazardly or in random array, all of which may be generally termed non-woven fibrous products. The invention also relates to methods for producing the bonded non-woven fibrous products or shaped articles therefrom. The bonded non-woven fibrous products are not only useful in the production of articles of either flat or threedimensional shape, but also as insulating material and the like as will be described more particularly hereinafter.

Hereinafter, the expression random array" is intended to include the array of fibers in a carded web wherein partial orientation is frequently present as well as other arrays in which the fibers are in a completely haphazard distributional relationship.

Heretofore, binders of thermosetting aminoplasts have been suggested as binders for bonding the fibers in nonwoven fabric structures; but these materials have various disadvantages, among which is the tendency to impart an off-white appearance or cast to the bonded products, and this tendency is so strong it is difficult to overcome even by the use of optical bleaches or by the use of white pigments, such as titanium dioxide. Also, the thermosetting materials heretofore used have generally produced products having an extremely brittle, boardy character when large proportions of the binder are used and products on which the fibers are generally poorly bonded when low proportions of the binder are used. Thermosetting binders previously used also required acidic catalysts which often exerted a degradative effect on the fibers, reducing their strength and/ or resiliency. Furthermore, many binders heretofore employed cannot be washed, scoured, or dry-cleaned. Also, these binders have a strong tendency to migrate to the surfaces of the fibrous products during drying of the products to which they have been applied.

It is an object of the present invention to provide fibrous products made with a thermosetting binder which can be applied by way of an aqueous system without the disadvantages mentioned above that are characteristic of previously applied aqueous thermosetting binder systems. A further object of the invention is to provide a bonded fibrous product of non-woven character in which the binder is adapted to be converted to an infusible and insoluble condition as by heating without the presence of a suitable catalyst as will be pointed out more particularly hereinafter. It is a further object of the present invention to produce bonded fibrous products of non-woven character from fibers which are incapable of felting, whether of natural or synthetic origin, and especially those which, unlike wool, are of non-proteinaceous charactor and have relatively smooth surfaces extending longitudinally of the fibers, and because of these surface characteristics are incapable of being converted into a felted product by normal felting operations. A further object. of the invention is to provide bonded fibrous products of 2,915,418 Patented Dec. 1, 1959 non-woven character wherein the binder may be substantially uniformly distributed through the body of the structure and has reduced tendency to migrate preferentially to the surfaces of the structure. Other objects and advantages of the invention will be apparent from the description thereof hereinafter.

In accordance with the present invention bonded nonwoven fibrous products are obtained by applying to the unbonded web or mat an aqueous dispersion containing, dispersed therein at a concentration of about 0.1 to 20% or more, a polyester-aminoplast condensation product which has excellent curing qualities, produces films of good adhesion and hardness, and yet is self-dispersible in aqueous systems. The condensation product used as the binder for the non-woven products of the present invention may be generally characterized as the coreaction product of at least two components (A) and (B) as follows:

(A) A special polyester having an average molecular weight of about 800 to 1500 containing hydroxyl groups available for condensation with the aminoplast and free carboxyl groups available for neutralization by means of ammonia, an amine, or a quaternary ammonium compound, and

(B) An aminoplast soluble in such organic solvents as butanol, isopropanol and monoalkyl ethers of diethylene glycol in which the alkyl group is methyl, ethyl, or th like.

COMPONENT A Component A is a special low molecular weight polyester containing hydroxyl groups adapted to enable its coreaction with the aminoplast (Component B) and some carboxyl groups for neutralization. The acid number of Component A should be between about 90 and about 100. This polyester is formed by first condensing a dibasic aliphatic acid having from 5 to 10 carbon atoms with a polyol or a mixture thereof containing at least 25 mole percent of a polyol having three or more hydroxyl groups therein. For example, the polyol may contain up to mole percent by weight of a diol, such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, and trimethylene glycol, 1,3-butane-diol, 1,4-butane-diol, and 1,5-pentane-diol. Examples of the polyols containing more than two hydroxyl groups that may be used include glycerine, sorbitol, pentaerythritol, iriositol, tetramethylolcyclohexanol, diand poly-pentaerythritol, and so forth, but tri-methylolethane is preferred. Preferably, the proportion of diol is not over 50 mole percent of the entire polyol component, and, of course, the diol may be completely absent.

The aliphatic dicarboxylic acid that is used may be adipic acid, succinic acid, glutaric acid, sebacic acid or the like. Preferably it contains from 5 to 8 carbon atoms, but it may contain 4 to 18 carbon atoms.

The polyol and dibasic aliphatic acid are mixed in the proportion of 1.2 to 1.8 moles of polyol to each mole of acid, preferably 1.2 to 1.5 moles of polyol being used for each mole of acid. The mixture is heated to a temperature within the range of about 200 to 260 C. either in the presence of an inert gas, such as carbon dioxide,

nitrogen, argon, helium, when atmospheric or higher pressures are employed. If desired, a reduced pressure may be present during the reaction to remove the water formed on esterification and to favor a shift in the equilibrium toward the esterification product. Pressures of 20 to 50 mm. or more absolute pressure may be used. Optionally, an esterification catalyst may be used, such as 0.1 to 1% of sulfuric acid, toluenesulfonic acid, zinc chloride, or phosphorus pentoxide. Such catalyst, however, is not necessary. The reaction is carried out until the acid number is reduced to a value of 10 or less.

Preferably, .the acid number is reduced to a value of less than 5.

The polyester obtained has terminal hydroxyl groups and also some hydroxyl groups at intervals along the polyester molecule.

Instead of using the free dibasic acid itself as one of the starting materials in this esterification reaction, there may be used the lower alkyl diesters of the dibasic acids, such as the dirnethyl or diethyl esters. Reaction in this case involves an ester interchange and sometimes has the advantage of yielding a product having less color. In this procedure, the alcohol liberated is boiled off.

Optionally, the polyester may be modified with a fatty acid having 8 to 30 carbon atoms, such as lauric acid, stearic acid, oleic acid, linoleic acid, linolenic acid, palmitic acid, and ricinoleic acid. The modification may be effected by drectly reacting the fatty acid with the polyol or with the hydroxyl-containing polyester; alternatively, the same result may be effected by transesterification, in which case an ester of the fatty acid, such as an ester thereof with glycerol, is reacted with the polyol or the hydroxyl-containing polyester in the presence of a suitable catalyst, such as an alkali metal alkoxide. There should be used from 1 to 3 moles of polyol or polyol mixture to each mole of the fatty acid (or the equivalent thereof in the case of an ester thereof when .transesterification is employed); preferably there is used from about 1.2 to 1.5 moles of polyol to each mole of acid or equivalent of ester. When modification with a fatty acid is resorted to, it is preferable to react the monobasic fatty acid or its ester (in the case of transesterification) with the polyol or a part of it before the polyol is reacted with the dibasic acid. Thus, when a modified polyester is desired, the fatty acid or ester thereof, such as a fat or oil, is first mixed with the polyol or polyol mixture and the esterification or transesterification with the monobasic fatty acid is carried out under the same conditions as stated hereinabove in respect to the esterification with a dibasic acid. Thus, the temperature may be from 200' to 260 C.; the pressure from 20 mm. absolute up to atmospheric or higher, an inert gas being used preferably at atmospheric or higher pressures. Optionally, an esterification or transesterification catalyst may be .used as before. The reaction is continued until the acid number reaches a value of or less. Preferably, it is continued until the acid number reaches a value of less than 1. It is desirable that the monobasic acid be completely bound up in the ester product, and to this end the most desirable condition is attained when the acid number approaches or reaches a value of Zero. The esterification product obtained from the polyol and monobasic acid is then mixed with the dibasic acid and any additional amount of polyol needed to bring the proportion of polyol used in the entire condensation reaction to a proportion of between 1.2 to 1.8 moles of polyol to one mole of the dibasic acid. This esterification reaction is continued at the same conditions as stated hereinabove in describing the preparation 'of the simple polyester unmodified with monobasic acid. As in the previous case, the reaction is continued until the acid number of the product is reduced to a value of 10 or less and preferably to a value of less than 5. The oil-modified polyester in this instance has some of its hydroxyl groups esterified with monoacyl radicals derived from the fatty acid. Of course, a mixture of fatty acids may be employed instead of a single one and similarly a mixture of dibasic acids may be employed instead of a single one whether an oil-modified polyester or an unmodified polyester is to be prepared up to this point.

The unmodified or oil-modified polyester thus prepared 1s then reacted with o-phthalic acid or o-phthalic acid containing lower alkyl substituents in the benzene ring, such as methyl, ethyl, propyl, or butylsubstituents or W1th .the anhydrides thereof. The useof the anhydrides are preferred because of their solubility in the polyester at this stage and the ease of reaction of one carboxylic group thereof, apparently .without appreciable reaction of both such groups which would lead to cross-linking, water-insolubility, and gelation. Any other polycarboxylic acid, such as isophthalic acid or terephthalic acid, has not been found satisfatcory in this phase of the preparation of the polyester, either because of insolubility and lack of reactivity therein, or, in some instances, because of rapid cross-linking to a water-insoluble, gel stage. The amount of the phthalic acid or its derivative or anhydride used is in the proportion of 2 to 3.5 moles for every 3 moles of the polyol. When the polyol consists entirely of one containing 3 hydroxyl units, it is preferred to use approximately 2 moles of the phthalic acid for 3 moles of the polyol. The reaction with the phthalic acid is believed to provide terminal carboxyphenyl groups on the polyester molecules. The reaction of the mixture of phthalic acid with the unmodified or oil-modified polyester may be efiected at a temperature of 150 to 170 C. for a period of 1 or 2 hours. The reaction is continued until'the acid number is reduced to 100 but is stopped before the acid number is reduced appreciably below 90. When the desired acid number within the range of to is reached, the reaction mixture is cooled to a temperature below 60 C. and preferably down to 20 or 30 C. to stop the esterification reaction. The reaction product thereby obtained provides Component A for reaction as will be described hereinbelow.

COMPONENT B Component B consists of an alkylated polymethylol nitrogen compound obtained by the reaction of formaldehyde or substances yielding formaldehyde and certain alcohols on a nitrogen compound selected from the group consisting of urea, thiourea, N,N'-ethylencurea(imidazolidinone-2), and triazines including guanamines, such as acetoguanimine and benzoguanamine, melamine and substituted melamines. The alkylation should be that resulting from an alcohol having from 3 to 6 carbon atoms, such as isopropanol, n-propanol, butanol, pentanol, hexanol, or cyclohexanol, so that the aminoplast will be soluble in such solvents as butanol, isopropanol, pentanol and the like. Examples of the substituted melamines include N,N-dialkylmelamines in which the alkyl group has from l'to 4 carbon atoms, e.g. methyl, ethyl, propyl, isopropyl, and n-butyl, also N,N-dialkylmel amines in which the alkyl group may be any of those just stated, N-monoalkylmelamines in which the alkyl group may be any of those just stated. The preparation of the alkylated polymethylol nitrogen containing compound is in itself no part of the present invention since these condensation products are well-known and available commercially.

I. Condensation product obtained by coreaction 0 f Components A and B The condensation product of Components A and B may be obtained by reacting a mixture of them in organic solvents at a concentration of 50 to 90% solids; for example, Component A may be dissolved in xylene, benzene, toluene, ketones, such as dioxane or methylethyl ketone, or in monoalkyl ethers of ethylene glycol, such as themonobutyl ether, butanol or mixtures of such solvents. Similarly, the aminoplast (Component B) may be dissolved in butanol or a mixture of butartol and xylene or in any other mixture of the various solvents just mentioned. Component A and Component B are reacted in ,proportions of about 40 to 60 parts by weight of Component A to about 60 to 40 parts by Weight of Component B. Preferably, the concentration of the reactantsin the organic solvent, and consequently of the reaction product therein,,is maintained as high as possible consistent with manipulability which depends upon the viscosity. The reaction of the mixture is effected in the Organic solvent solution at a temperature of 50 to 120 C., and preferably at a temperature of 70 to 90 C., at atmospheric pressure. The reaction is carried out until a sample to which an amine (such as of triethylamine on Weight of condensate solids) is added is soluble in water. Generally, the reaction is accompanied by an advance in viscosity of about 3 to 10 poises when measured at 60% solids concentration in any particular organic solvent at room temperature.

The reaction product is cooled below 60 C., such as to 25 to 55 C., and then it is neutralized or at least partially neutralized with ammonia, an amine, or a quaternary ammonium compound. If desired, a small proportion of the neutralizing component may be a fixed base, such as potassium or sodium hydroxide, or carbonates. However, it is preferred to use as the entire neutralizing agent either ammonia, a volatile amine or a quaternary ammonium compound or a mixture of 2 or 3 of such materials. When ammonia is the neutralizing agent, it is generally introduced as an aqueous solution. Preferably the ammonia is rather concentrated when it is desired to store or ship the product in order to save bulk. However, the ammonia may be sufficiently dilute to directly produce an aqueous solution or dispersion of the condensation product of the present invention having the desired solids concentration for direct application to the non-woven fibrous web or mat. When an amine or a quaternary ammonium compound is used as the neutralizing agent, it may be added without adding water so that the neutralized condensation product of the invention is essentially anhydrous but is capable of practically unlimited dilution with water without being coagulated. Such amines as monoethylamine, triethylamine, dimethylamine, trimethylamine, and morpholine are quite suitable as neutralizing agents. Also quaternary ammonium compounds, such as choline, trimethylbenzylammonium chloride, octadecylbenzyldimethylammonium chloride, methylpyridinium chloride, may be used for neutralization. As in the case of the amines, they may be used without the addition of water so that the product is obtained as a substantially anhydrous solution which is dilutable with Water to practically unlimited extent. If desired, the amines or the quaternary ammonium compounds may be introduced as aqueous solutions and, in the case of ammonia, a dilution may be such as to provide the concentration of the condensation product desired for application. On the other hand, the substantially anhydrous products obtained by neutralization by an amine or a quaternary ammonium compound may be stored or shipped in that concentrated form and then diluted with water for application at the point of its destined use.

COMPONENT C Component C, when used, may be any of the common alkyd resins including oil-modified alkyd resins. For example, simple alkyds that may be used may be those obtained by condensing a dicarboxylic acid, such as ophthalic, terephthalic, isophthalic, pyromellitic, succinic, glutaric, adipic or sebacic acids, with a polyhydric alcohol, such as ethylene glycol, diethylene glycol, glycerol, pentaerythritol, sorbitol, inositol, trimethylolethane, tetramethylolcyclohexanol, diand poly-pentaerythritol. Preferably the polyhydric alcohol component from which the alkyd is derived comprises at least 25% by weight of at least one alcohol containing at least three hydroxyl groups in order to provide an excess of hydroxyl groups available for reaction with the aminoplast (Component B). If desired, there may be used as a part of the dicarboxylic acid component one or more ethylenically unsaturated acids, such as maleic acid, fumaric'acid, or the polycarboxylic acid compounds obtained by interacting maleic anhydride with abietic acid, ricinoleic or eleostearic acids. The unsaturated dicarboxylic 'acid may amount to fifty percent of the total dicarboxylic acid used, but is preferably not over 25% of such total.

The alkyds may be modified with a higher monobasic aliphatic acid having 12 to 30 carbon atoms, such as a fatty acid or fatty acid mixture derived from drying, semidrying, or non-drying oils or fats in which the fatty acid has from 12 to 30 carbon atoms and up. The modifying fatty acid may be lauric acid, myristic acid, coconut oil fatty acids, palm oil fatty acids, palmitic acid, oleic acid, stearic acid, linolenic acid, or fatty acids obtained by hydrogenation of fish, animal, or vegetable oils or fats.

In preparing the alkyd, the glycerol or other polyhydric alcohol or mixture thereof may first be partially esterified with the monoacid or mixture thereof, and the resulting partial ester may then be reacted with the dicarboxylic acid, such as phthalic acid. Alternatively, the dicarboxylic acid, the polyhydric alcohol and the monocarboxylic acid may be mixed together and reacted simultaneously. It is preferred to use alkyds modified with essentially saturated, non-drying fatty acids to assure freedom from yellowing and embrittlement on ageing. Preferred alkyds may be obtained from 39 to 50% phthalic acid, 20 to 30% glycerol, and 30 to 35% coconut fatty acids. The preparation of the alkyd is in itself no part of the present invention, since conventional oil-modified alkyds may be used.

The alkyd of which Component C is constituted is II. Condensation product obtained by coreaction of Components A, B, and C The condensation product of Components A, B, and C is obtained by first reacting the aminoplast (Component B) with the alkyd (Component C). They may be reacted in organic solvents at a concentration of 50 to solids; for example, Component C may be dissolved in xylene, benzene, toluene, ketones, such as dioxane or methylethyl ketone, or in monobutyl ether of ethylene glycol, butanol or mixtures of such solvents. Similarly, the aminoplast (Component B) may be dissolved in butanol or a mixture of butanol and xylene or in any other mixture of the various solvents just mentioned. Component B and Component C are reacted in proportions of about 20 to 30 parts by weight of Component C to about 20 to 30 parts by weight of Component B. The reaction of the mixture is effected in the organic solvent solution at a temperature of 60 to 120 C., and preferably at a temperature of 70 to C., at atmospheric pressure. The reaction is carried out until an advance in viscosity of at least 3 poises is obtained when measured at 60% solids concentration in any particular organic solvent at room temperature.

The organic solvent solution of the reaction product of B and C is then mixed with the polyesters of Component A whether unmodified or oil-modified in proportions of about 40 to 60 parts by weight of Component A, preferably about 50 parts thereof, to 50 parts by weight of the reaction product of B and C. Component A may be added to the reaction product of B and C as such or it may be dissolved first in an organic solvent, such as toluene, xylene, benzene, or monoalkyl ethers of ethylene glycol, such as the monobutyl ether thereof, at concentrations of 50 to 90% solids, preferably as high as possible consistent with the working of viscous medium. The reaction is effected in the organic solvent solution at 50 to 80% solids content at a temperature of about 60 C. for about one-half hour. Preferably, the concentration of the reactants in the organic solvent, and consequently of the reaction product therein, is

7 maintained as high as possible consistent with manipulability which depends upon the viscosity. Th1s reaction is continued for a time sutficient to raise the viscosity at least ,2 poises when measured at 60% sollds concentration in an organic solvent at room temperature.

The reaction product is cooled below 60 C., such as to 25 to 55 C., and then it is neutralized or at least partially neutralized with ammonia, an amine, or a quaternary ammonium compound. If desired, a small proportion of the neutralizing component may be a fixed base, such as potassium or sodium hydroxide, or carbonates. However, it is preferred to use as the entlre neutralizing agent either ammonia, a volatile amine or a quaternary ammonium compound or a mixture of two or three of such materials. When ammonia is the neutralizing agent, it is generally introduced as an aqueous solution. Preferably the ammonia is rather concentrated when it is desired to store or ship the product in order to save bulk. However, the ammonia may be sufficiently dilute to directly produce an aqueous solution or dispersion of the condensation product of the present invention having the desired solids concentration for direct application. When an amine or a quaternary ammonium compound is used as the neutralizing agent, it may be added without adding water so that the neutralized condensation product of the invention is essentially anhydrous but is capable of practically unlimited dilution with water without being coagulated. Such amines as monoethylamine, triethylamine, dimethylamine, trimethylamine, and morpholine are quite suitable as neutralizing agents. Also, quaternary ammonium compounds, such as choline, trimethylbenzylammonium chloride, octadecylbenzyldimethylammonium chloride, and methylpyridinium chloride, may be used for neutralization. As in the case of the amines, they may be used without the addition of water so that the product is obtained as a substantially anhydrous solution which is dilutable with water to practically unlimited extent. If desired, the amines or the quaternary ammonium compounds may be introduced as aqueous solutions and, in the case of ammonia, a dilution may be such as to provide concentration of the condensation product desired for application. On the other hand, the substantially anhydrous products obtained by neutralization by an amine or a quaternary ammonium compound may be stored or shipped in that concentrated form and then diluted with water for application at the point of its destined use.

The binder of the present invention has good adhesion to all sorts of fibers and filaments and even to those of siliceous character which, in the past, have been difficult to handle because of the ditficulty of finding colorless binder materials which are adequately adhesive toward the siliceous material such as glass. The binders of the present invention are also substantially free of discoloration when subjected to elevated temperatures, such as those used for drying, fusing, or curing.

The binder of the present invention is adapted to be insolubilized and rendered infusible on heating without using acidic catalysts. The cured or baked fibrous product provides good resistance to laundering, drycleaning and spotting, to various chemicals, and to heat. They are characterized by excellent resistance to ironing in which operation they are not subject to tackiness as would be true of thermoplastics heretofore used. The binders of the present invention are characterized not only with good adhesion to hydrophilic fibers like cotton, regenerated cellulose rayons and the like, but they are also characterized by excellent adhesion to hydrophobic types .of fibers, ,such as the nylons and especially the polyamide types, the vinyl resins such as copolymers of vinyl chloride with vinyl acetate or with acrylonitrile, polymers .of 70 to 90% acrylonitrile with other monomers such as vinyl chloride, vinyl acetate, any of the vinyl pyridines such as 2-vinyl pyridine or mixtures of such auxiliary comonomers, polyesters such as poly(ethylene glycol terephthalate), and cellulose esters such as cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate and so on. Because of the characteristic adhesion of the binder of the present invention to both hydrophilic and hydrophobic types of fibers, the fibrous products are characterized by excellent resistance to pilling and abrasion. The binder of the present invention is adapted to be dried and then cured to insoluble and infusible condition so that the bonds cannot be disturbed even under severe conditions of heat. The fibrous products using the binder of the present invention have the advantage also that they can be embossed durably in wet condition or during the first drying but before complete drying. While the binder may be preferentially applied, if desired, to portions of the fibrous product, such as one or both of the faces thereof, it is characteristic of the binder of the present invention that if such preferential treatment is not desired, substantially uniform distribution may be obtained because of the reduced tendency of the binder after initial distribution throughout the body of the fibrous product to migrate to the surfaces thereof during drying.

The binder of the present invention may also contain: dyes of water-dispersible type if coloration is desired; lubricants and/or softeners of water-dispersible type, especially amine salts of long chain fatty acids, such as triethanolamine oleate, partial esters of polyhydric alcohols with higher fatty acids, such as sorbitan monostearate or ethylene oxide condensation products thereof with 1 to 10 or even 50 or more oxyethylene units per molecule, or quaternary ammonium compounds having a long chain aliphatic group such as octadecyltrimethylammonium chloride; antistatic agents, such as sodium lauryl sulfate, and those of quaternary ammonium type such as that just mentioned as a softener; wetting agents to aid penetration such as sodium dioctylsulfosuccinate; a foaming agent, such as soaps, like sodium oleate, if it is desired to provide the binder in foamed condition; and so on. Any one of these agents may be used in an amount of from about 0.01 to 2% or more on the weight of the aqueous dispersion but generally in an amount which is not over 5 to 10% by weight of the binding agent, that is one of the polyester-aminoplast condensates described above.

The cured or insolubilized binders are unaffected by water or organic solvents, such as styrene, even at molding temperatures, whereby the bonded fibrous products are adapted to be used as molding preforms or molding inserts for the production of molded articles from various thermosetting resins as will be pointed out in more detail hereinafter. The binders are also free of cold flow and are resistant to flow at elevated temperatures, whereby shifting of the fibers or filaments in the bonded products is substantially completely prevented even at elevated temperatures during subsequent molding with such prod-- ucts being used as reinforcing inserts or preforms.

In accordance with the present invention, the fibers of the non-woven web may comprise wool or may consist entirely of non-proteinaceous fibers which are incapable of felting. The fibers are present in the form of a socalled non-woven mat in which they are haphazardly distributed, or the mat may be formed by carding when the fibers are of such a character, by virtue of length and flexibility, as to be amendable to the carding operation. Natural fibers like wool, linen, silk, jute, sisal, ramie, hemp, and cotton may be used, as well as many artificial fibers or filaments including rayon, those of cellulose esters such as cellulose acetate, vinyl resin fibers such as those of polyvinyl chloride, copolymers of vinyl chloride with vinyl acetate, vinylidene chloride or acrylonitrile containing a major proportion of vinyl chloride in the polymer molecule, polyacrylonitrile and copolymers of acrylonitrile with vinyl chloride, vinyl acetate, methmat, alternate layers of carded webs may be disposed with their fiber orientation directions disposed at 60 or 90 angles with respect to intervening layers.

Mats may also be formed by the deposition of fibers, either natural or artificial, from an air stream. Thus, continuous filaments may be fed to a cutter or breaker which discharges the fibers into the discharge side of a blower. Suitable conduits are provided to guide the fibers to a collecting screen or air-pervious structure for collecting the fibers in the form desired. The screen may be in the form of an endless traveling belt passing through the lower portion of a tower into the upper portion of which the blown fibers are introduced by the conduit work. A suction box may be disposed beneath the upper course of the traveling screen to assist in the deposition of the fibers thereon. Instead of having a traveling fiat screen, a stationary formed screen may be used. For example, it may take the form of a hat-shaped cone such as that used in the felt hat-making industry. Alternatively, it may have any other form suitable to produce the desired shape of the fibrous product, such as a rectangular tray. Again, suction may be applied beneath the screen to assist deposition of the fibers thereon.

The fibers and filaments may be formed by direct spraying from a solution or molten mass thereof. This is a conventional procedure for the formation of glass fibers or mineral wool fibers as well as those of nylon or of thermoplastic materials, such as vinyl resins of the type mentioned hereinabove, adapted to be dissolved in a suitable solvent, such as acetone or dimethyl formamide, or to be melted. The solution or melt is, of course, directed to suitable nozzles or jet-forming orifices and a high pressure fluid stream, such as of cold or hot air or of inert gases such as nitrogen or even of steam, is directed against the stream or streams of filament-forming material to disrupt them and coagulate them as fibers in the vicinity of the orifices. Electrostatic spinning methods may also be employed for this purpose. As in the case of the use of blowers, the disrupted and dispersed fibers may be directed to the top of a settling tower and be allowed to settle, with the aid of suction devices, upon a suitable traveling or stationary screen at the bottom of the tower. This procedure is adaptable to the production of fibers of siliceous materials such as glass or mineral wool as Well as to thermoplastic resin fibers mentioned above.

Another procedure may involve the extrusion of continuous filaments, either from solutions of the filamentforming material or from molten masses thereof, and the cutting or breaking of the filaments to fibers of a predetermined length which may be fed to a hopper at the top of a settling tower into which they may be discharged by conventional feeding devices, and at the bottom of which a traveling or stationary screen may be deposited for collection of the fibers.

The fibers and filaments that may be used in the pres- .ent invention' may be natural or artificial as stated above. The selection of the particular material of which the fiber is made frequently depends upon the use intended of the product. For example, siliceous fibers are extremely valuable in the production of molded articles because of the exceptional strength obtained by their use. Used for filtration purposes, fibers of certain resins may However, when the bonded fibrous products are be preferred to provide resistance to attack by acids or alkalies that may be present in the liquids to be filtered. Thus, polymers containing a high percentage of acrylonitrile or of vinyl chloride or even of such highly halogenated resins as polytetrafiuoroethylene or poly(chlorotrifluoroethylene) may be more useful in such cases. For certain purposes, it may be desirable to form the fibrous products from a mixture of fibers of different types. An example is the use of a mixture of thermoplastic fibers of potentially adhesive character with other fibers which lack such potentially adhesive character. A fibrous product comprising such a mixture may be heated to the appropriate temperature to render the potentially adhesive fibers tacky to effect binding of the fibers in the product by this procedure as well as by the binders of the present invention.

The binder dispersion may be applied to the dry fibers after the formation or deposition of the web or mat so as to penetrate partially into or completely through the interior of the fibrous products. Alternatively, the binder dispersion may be applied to the fibers as they fall through a settling chamber to their point of deposition. This is advantageously obtained by spraying the binder dispersion into the settling chamber at some intermediate point between the top and the bottom thereof. By so spraying the fibers as they descend to the point of collection, it is possible to effect a thorough distribution of the binder among the fibers before they are collected into the product. In the production of certain fibrous products wherein a hot molten mass of a polymer, such as nylon or a fused siliceous mass or glass, is disrupted by jets of heated air or steam, the binder dispersion may be sprayed directly on the fibers while still hot and very shortly before their deposition so that quickly after deposition the binder is set and bonds the fibers in proper relationship. Preferably, however, application of the binder dispersion to the fibrous product is made at room temperature to facilitate cleaning of the apparatus associated with the application of the binder dispersion. The binder dispersion may be applied to one or both surfaces of the fibrous product or it may be distributed through the interior as well.

The binder of the present invention may be applied in conjunction with other binders. For example, another type of binder, such as glue or resin-forming condensates, especially aminoplasts such as urea-formaldehyde, melamine-formaldehyde and the like, may be applied either to the interior or to the external surfaces of the fibrous product while the binder of'the present invention is applied'to the external surfaces or to the interior of such products. Similarly, the use of potentially adhesive fibers within the fibrous product may also be resorted to in conjunction with the use of a binder of the present invention. The aqueous dispersion may also contain dissolved therein a water-soluble thermosetting condensation product, especially the aminoplasts, namely the low molecular weight or monomeric reaction products of an aldehyde, and especially formaldehyde with urea, thiourea, biuret, or other homologues or derivatives thereof, such as N,N-ethyleneurea, N,N-ethyleneurea, N,N-dimethylurea, N,N-diethylurea, N,N'-dimethoxymethylurea, N,N-dimethoxymethylurea, N,N-diethoxyethylurea, tetramethoxymethylurea, tetraethoxyethylurea. Similar reaction products of formaldehyde with triazines, such as melamine may also be employed, such as N,N- dimethylmelamine and alcohol-modified melamine-formaldehyde thermosetting resin condensates, eg 0 fmethyl and ethyl alcohols, for example, dimethoxymethyl-monomethylolmelamine.

The use of an auxiliary aminoplast with the aminocontaining polymers of the present invention serves to modify the hand, and frequently increases the strength and resistance to creasing, wrinkling, and crushing.

The auxiliary aminoplast binder may be used in an amount up to 25% by weight of the weight of the poly- 1 l esterrgminoplast condensate, 2 to 11% being preferably employed when the combination binder system is used.

Whether or not an aminoplast binder is used, there may be introduced into the system either into the aqueous dispersion of the polyester-aminoplast condensate or by separate application to the non-Woven fibrous mat or web before or after application of the aqueous dispersion of the polymer, an acid catalyst for accelerating the curing .of the binder. The catalyst is not necessary, but may be used in an amount up to 2%, preferably about /2 to 1% on the weight of the auxiliary aminoplast. The catalyst used may be selected to avoid excessive deterioration of the fibers used in the particular fibrous product, but it is in any case an acidic or potentially acidic material, the latter serving as a latent catalyst and liberating acid on heating. For example, when cellulosic fibers are employed, a latent ammonium salt, such as ammonium chloride or diammonium phosphate or a latent amine hydrochloride salt, may be employed such as the hydrochloride or triethanolamine, monoethanolamine, diethylamine and so on. It is believed that the binder of the present invention is chemically combined with such fibers as contain chemically reactive groups, such as in cellulosic fibers.

Generally, the proportion of the binder of the present invention to the weight of the fiber component of the fibrous product may vary widely depending on the character of the product desired. For the production of preforms, intended to be converted into molded articles, it is preferred to employ from 2 to of the binder of the present invention based on the weight of fibers. In the production of insulation masses, the amount of binder employed may fall in the lower part of the range just specified if the binder is applied primarily adjacent to the surface or surfaces of the product or if it is applied in conjunction with other binders. The aqueous dispersion of the polyesteraminoplast condensate is generally applied at a concentration of 0.1 to 20% solids and preferably at a concentration of about 1 to 3% binder solids by weight.

The fibrous product of non-woven character may contain from about /2 to about 200%by weight on the weight of the fibers depending on the purpose for which the product is to be used. When the binder is to serve mainly to bond the fibers together to form a coherent unitary structure in which the maximum porosity is retained in conjunction with a minimum change of natural fiber hand, there may be employed from /2 to 1% by weight of binder solids on fiber, the lower proportion of course giving the maximum porosity possible and providing a minimum change in the natural fiber hand although even with the larger proportion in this range, the porosity is mainly retained and the fiber hand is still evident. The products thus obtained are quite useful for many sanitary uses such as table napkins,

bibs, table cloths, sanitary napkin covers, disposable diapers, disposable sheets, and surgical dressings and compresses. It is characteristic of the binder applied in the proportions just stated that there is relatively little or no window paning, that is, the interstices between fibers are left open leaving a highly porous bulky product. Of course, the density of the product can be effected or modified by the application of pressure to varying extends prior to or, in many cases, even after the curing of the product.

Fibrous products of non-woven character using from 2 to 30% by weight of the binder of the present invention on the weight of the fiber are generally quite useful for garment uses to provide interlining fabrics for coats, dresses, and so on, or to provide outer Wearing apparel fabrics, such as blouses, skirts, shirts, etc. The garments made of these fabrics need little or no ironing or pressing to restore their appearance, shape, and hand after hand-washing, machine-laundering and drying operations. Besides the general household and apparel 12 uses mentioned above, fibrous products of the invention, in which to 20% by weight of binder on the weight of fiber is employed, find many light industrial uses as wiping cloths, lining materials for packaging as filters, and packings and gaskets for industrial machinery.

Fibrous products of the present invention, in which 20 to 150% by Weight of the binder on the weight of fiber is used, are especially useful for heavy industrial uses where durability and resistance to wear are desired, such as in industrial gaskets, packings, filters, and so on. The products containing 20 to of the binder of the present invention on the weight of the fiber are useful as laminating layers, either as interlayers or backing sheets in conjunction with plastic films and sheets as of polyethylene, nylon, and so on, or in conjunction with textile fabrics of woven, braided, knitted, knotted, or felted character.

To render the binder infusible, curing at elevated temperatures is effected. Curing temperatures may be as high as 400 C. for setting the binder, but preferably are in the range from about C. to 350 C. The curing serves to render the binder insoluble and infusible and, as stated hereinabove, may be assisted by the use of an acidic catalyst.

As pointed out hereinbefore, the application of the polymers containing thermosetting aminoplast groups is adapted to provide fibrous products having a wide range of characteristics. When the binder is present in an amount of about Me to 2% on the weight of the fibers in the fibrous product, the latter retains a textile hand. In all of the fibrous products previously mentioned, the products are characterized by freedom from discoloration and excellent resistance to ultraviolet light, to laundering, to dry-cleaning and spotting, to various chemicals, and heat as in ironing, and durability of any embossed pattern. They are also characterized by good adhesion of the binder to the fibers.

The binder of the present invention is essentially colorless and has the advantage that it undergoes no discoloration at the elevated temperature needed for the drying or baking of the fibrous products or even for the formation of molded articles with the fibrous products of the present invention used as preforms and ultimately occurring as a reinforcing component in the molded article. The binder of the present invention is resistant to flow at elevated temperatures so a thermoplastic or thermosetting resin can be applied and the composite thereby obtained can be molded at elevated temperature without appreciably disturbing the disposition of fibers in the mass. Similarly, the binder is insoluble in water and organic solvents so that the presence of such materials during subsequent treatment as in molding cannot disturb the disposition of fibers. Consequently, there is no washing of fibers in the preform with accompanying tendency to form resin-rich areas and fiberrich areas in the molded article giving rise to such nonuniformity which tends to cause cracking or crazing in the molded articles and resulting weakness in the reinforced structure.

All of these properties render the binder outstandingly valuable in connection with siliceous fibers, such as those of glass or mineral wool, in the production of preforms adapted to be used for forming molded articles. While molding resins or resin-forming materials of numerous thermoplastic and thermosetting types may be employed, the use of thermosetting types of polyesters is particularly advantageous. Such a resin-forming material may comprise an unsaturated polyester (such as a polyester of mixed maleic acid and phthalic acid (in a 50:50 molar ratio) with a glycol, such as propylene glycol, dissolved in styrene or other copolymerizable monoethylenically unsaturated monomers having solvent properties for the low condensed polyester. Most binders heretofore used in the preforrns become discolored duringthe moldi r pe at qn n in e fe e th h pen ra .o it is:

molding resin, especially when it is of a polyester type, so that the fused resin is poorly bonded to the portions of the fibers coated by the binder which in turn is manifested by a reduced transparency and corresponding lack of continuity and homogeneity. The binder of the present invention is resistant to such discoloration. In addition, it does not interfere with the penetration of the resin-forming material to the fibers of the preform during the molding operation. This provides excellent transparency and a high degree of homogeneity and continuity in the product. Also, the binders of the present invention assure the maintenance of the distribution of the fibers during the handling of the preform up to the molding operation.

The fibrous products of the present invention are capable of numerous uses, many of which have been mentioned abo e. Thus, the fibrous mats bonded with the improved binders of the present invention may serve as heat or sound insulation materials, as filters for air systems or liquid systems, as permeable membranes as in storage batteries or electrolytic condensers, as cushion ing or padding materials for upholstering purposes and so forth.

As pointed out hereinabove, fibrous mats or fabrics of siliceous fibers are extremely valuable as reinforcements for molded products using the bonded fibrous mat or fabric as a preform with appropriate molding powders or syrups. For example, the bonded mat or the bonded laminar fabric assembly may be introduced into a closed mold system with an appropriate amount of a thermosetting resin powder or liquid, such as of resin-forming condensates of urea-formaldehyde, melaminefrmaldehyde, phenol-formaldehyde or polyesters, such as those described in U.S. Patents 2,255,313 and 2,607,756. From to 45% by weight of the molded article may be composed of the reinforcing fiber network when a mat is used as the preform or, in the case of a fabric reinforcement, from 5 to 65% by weight of the molded product may consist of the composite of bonded fabric laminations. 1

Instead of using a thermosetting resin-forming material as the molding resin, there may be used thermoplastic types of resins such as the vinyl or acrylic types of resins. For example, polymers and copolymers of vinyl acetate, vinyl chloride, acrylonitrile, styrene, acrylic and methacrylic acid esters; e.g. the methyl, ethyl, propyl, or butyl esters thereof, and so on. Advantageously, a polymer or copolymer may be dissolved in its corresponding monomer or mixture of monomers to provide a solution that may readily be introduced into the'mold.

The following examples are illustrative of the fibrous products and the methods for making them in accordance with the present invention and parts and percentages are by weight unless otherwise indicated:

PREPARATION OF BINDERS 1. Component A EXAMPLE A Into a reaction vessel, there are introduced 292 grams of adipic acid (2.0 moles) and 360 grams of trimethylolethane (3 moles). Heat and reduced pressure are applied and the batch held at 230 C. until the acid number value falls below 4.0. The reaction mixture is then cooled to ca. 160 C., vented and 296.0 grams of o-phthalic anhydride (2.0 moles) is charged. The mixture is heated to 150 to 160 C. at atmospheric pressure and held at this temperature until the acid number of the batch falls to ca. 100. -At this point, full cooling is applied to the-batch and suflicient xylol is charged to adjust the solids content of the batch to ca. 85%.

EXAMPLE B The procedure of Example A is repeated replacing the adipic acid with 404.0 grams of .sebacic acid (2 14 moles) and the polyol with 332.0 grams of glycerine (3.6 moles).

- EXAMPLE C The procedure. of Example A is repeated replacing the adipic acid with 236.0 grams of succinic acid (2 moles) andthe polyol with 437.0 grams of sorbitol (2.4 moles).

EXAMPLE D The procedure of Example A is repeated replacing the adipic acid with 264.0 grams of glutaric acid (2 moles) and the polyol with 340.0 grams of pentaerythritol (2.5 moles).

EXAMPLE E The procedure of Example A is repeated replacing the polyol with a mixture of 233.0 grams of diethylene glycol (2.2 moles) and 96.0 grams of trimethylolethane (0.8 mole).

EXAMPLE F 200 grams (1.0 mole) of lauric acid and 156.0 grams (1.3 moles) of trimethylolethane are heated under reduced pressure (total pressure=ca. 30 mm. Hg) to a temperature of 230 C. The mixture is held at this temperature until the acid number of the batch (mg. KOH reqd to neutralize 1.0 gram) falls below 1.0. The system is then cooled to below 170 C., vented and 292.0 grams of adipic acid (2.0 moles) and 204.0 grams of trimethylolethane (1.7 moles) are charged. Heat and reduced pressure are re-applied and the batch again held at 230 C. until the acid number value falls below 4.0. The reaction mixture is then cooled to ca. 160 C., vented and 296.0 grams of o-phthalic anhydride (2.0 moles) is charged. The mixture is heated to 150 C. to 160 C. at atmospheric pressure and held at this temperature until the acid number of the batch falls to ca. 100. At this point, full cooling is applied to the batch and sufficient xylol is charged to adjust the solids content of the batch to ca.

l EXAMPLE G The procedure of Example F is followed substituting 364.0 grams of sebacic acid (1.8 moles) for the adipic acid.

EXAMPLE H The procedure of Example F is followed substituting 138.0 grams of diethylene glycol (1.3 moles) for the first charge of trimethylolethane.

EXAMPLE I EXAMPLE J The procedure of Example F is followed substituting 427.0 grams of stearic acid (1.5 moles) for the lauric acid.

EXAMPLE K Charge 444 grams of soybean oil to a reaction vessel along with grams of trimethylolethane (1.0 mole). Heat is applied to the mixture and nitrogen gas is sparged through the batch continuously throughout the reaction. At C., 1.0 gram of a 25 solution of sodium methylate in methanol is added to the batch. The heating is continued. At C., 0.5 gram of triphenylphosphite is charged to the batch. Heating is continued to a batch temperature of 230 to 240 C. The mixture is held in this temperature range about five minutes until a clear pill is obtained in cooled droplets from a. rod dipped into the mixture. The mixture is then cooled to approximately 180 C., at which point there is charged 438 grams (3 moles) of adipic acid and also another 360 grams (3 moles) of the trimethylolethane, and heating is once more resumed. The batch is heated to 260 and held at this temperature until the acid The procedure of Example K is repeated substituting 444.0 grams of coconut oil for the soybean oil.

II. Binders formed of Components A and B EXAMPLE M A mixture of 100 grams. of a 60% solution in xylene of a butylated polymethylolmelamine and 100 grams of the polyester product of Example A is stirred at room temperature for about one-half hour to insure reasonably thorough mixing before any heat is applied. The mixture is then heated to 55 to 60 C. and held in this range for one-half hour. At the end of this time, reaction is stopped by applying cooling to the batch and adding an amount of concentrated 28% aqueous NH;, or triethylamine (100%) equal to of the weight of polyester solids present.

EXAMPLE N The procedure of Example M is followed substituting 120 grams of the polyester of Example F for the polyester of Example A therein used.

EXAMPLE 0 The procedure of Example N is repeated in successive runs substituting for the polyester there used 120 grams of each of the polyesters of Examples B to E and G to L.

EXAMPLE P The procedure of Example N is followed except that 120 grams of the polyester of Example K is substituted for the polyester of Example F.

EXAMPLE Q The procedure of Example M is repeated except that 100 grams of a 50% solution of a butylated dimethylolurea is substituted for the melamine resin.

EXAMPLE R The procedure of Example M is repeated except that 100 grams of a 45% solution of N,N'-diisopropoxymethyl-imidazolidinone-Z is substituted for the melamine ;re sin.

EXAMPLE S The procedure of Example N is repeated substituting 100 grams of a 60% solution in xylene of a butylated polymethylol-N,N-dimethylmelamine.

III. Binders formed of Components A, B, and C EXAMPLE I A mixture of 100 grams of a 60% solution in xylene of a butylated polymethylolmelamine and 100 grams of a 60% solution in xylene of a coconut oil-modified .glycerol-phthalic acid alkyd resin is heated with agitation to 70 to 80 C. at atmospheric pressure. The mixture is held at this temperature with continuous agitation until the viscosity of the batch advanced about 15 -p oises from its original viscosity (when measured at .C. and at a 60% concentration). The reaction is then stopped by cooling the batch to room temperature. During the cooling, there is gradually added 100 grams of the polyester product of Example A.

The entire mixture is stirred at room temperature for ca. /2 hour to insure reasonably thorough mixingbefore any heat is applied. The mixture is then heated to 55 to 60 C. and held in this range for one-half hour. A! the end-of this time, reaction is stopped by applyingcooling tto the *batch and adding an amount of concentrated" I 16 ewes- H3 9 28%) v sm (101 09411 21 9 9 at h ei h of P y r 9 21? n w.-

EXAMPLE U The procedure of Example T is followed substituting 120 grams of the polyester of Example F for the polyesterof Example A therein used.

The coreaction product obtained is neutralized with triethylamine.

Ex MP E v The procedure of Example U is repeated in successive runs substituting for the polyester there used 120 grarns of each of the polyesters of Examples B to E and Q to L.

EXAMPLE W The procedure of Example U is followed except that 120 grams of the polyester of Example K is "substituted for the polyester of Example F and 100 grams of a 60% solution in xylene of a' linseedoil-modified glycerol pht halate is substituted for the alkyd solution there used.

EX E 1?.

The procedure of Example T is repeated except that 100 grams of a 50% solution of a butylated dimethylolurea is substituted for the melamine resin.

EXAMPLE Y The procedure of Example T is repeated except that 100 grams of a 45% solution of N,N-diisopropoxy methyl-imidazolidinone-Z is substituted for the melamine resin.

EXAMPLE Z The procedure of Example -U is repeated substituting 100 grams of a 60% solution in xylene of a butylated polymethylol-N,N-dimethylmelamine.

IV. Bonded non-woven fabrics EXAMPLE 1 uct of Example P diluted with waterto a 2.5% solids concentration at a wet pick-up of about 600% on the Weight of the fibers. The Web is dried and cured .by heating five minutes at 240 C. The resulting nonawoven fabric has about /15 fiber/binder weight ratio. It is highly porous and resilient. I

(b) The procedure of part a.is repeated with :Pyrex glass fibers, except that thecarded web weighs /zounce per square yard and impregnation with the aqueousdispersion is effected at a wet pick-up of 300%, giving a weight ratio of about 92/8 fiber to binder in the final fabric which is porous, flexible, and coherent. It is resistant to laundering and dry-cleaning.

(c) The procedure of part a is repeated with aqueous dispersions of the same polyester-aminoplast condensate, but at concentrations of 0.15%, 1%, 5%, 10%, 15%, and 20% instead of 2.5%. The products obtained with the higher concentrations show progressive increase in stifiness but without acquiring a rough,-harsh hand. The lower percentages produced softer products which nevertheless were coherent and well-bonded even at the lowest percentage concentration used. 1

EXAMPLE .2

. is resistant to laundering and dry-cleaning.

(b) The procedure of parta is repeated with aqueous dispersions of the same polyester-aminoplast condensate, but at concentrations of 0.15%, 1%, and instead of 2.5%. The products obtained with the higher concentrations show progressive increase in stiffness but without acquiring a rough, harsh hand. The lower percentages produced softer products which nevertheless were coherent and well-bonded even at the lowest percentage concentration used.

EXAMPLE 3 A 50/50 white nylon/dispersed-dyed bright acetate (both fibers 3 denier, 1.5 inch staple) random web obtained by air-deposition weighing about 1.5 oZ./sq. yd. is impregnated with an aqueous dispersion obtained from the triethylamine-neutralized product of Example U diluted to a concentration of 1.0% and containing 0.08% of benzyldimethyloctadecylam monium chloride at about 600% wet pick-up. The web is dried and cured five minutes at 240 F. The resultant non-woven fabric is quite porous and has an essentially textile hand. After washing and drying, no ironing or pressing is needed to restore the shape, appearance, or hand of garments made of the fabric.

EXAMPLE 4 A 50/50 white viscose/dyed Acrilan (polymer of about 85% to 90% acrylonitrile) (both fibers 3 denier, 1.5 inch staple) random web obtained by air-deposition weighing about 1.75 oz./sq. yd. is impregnated with an aqueous dispersion obtained from the triethylamineneutralized product of Example V diluted to a concen tration of 1.0% and containing 0.08% of benzyldimethyL octadecylammonium chloride at ca. 600% wet pick-up. Dried and cured 1.5 min. at 260 F. Product has good coherence, porous, soft, textile hand.

EXAMPLE 5 A 55/45 nylon/viscose (both fibers 5 denier, 1.75 inch staple) random web obtained by air-deposition is impregnated with an aqueous dispersion obtained from the tri' ethylamine-neutralized product of Example W diluted to a concentration of 1.5% and containing 0.08% of benzyldimethyloctadecylammonium chloride at ca. 400% wet pick-up. Dried and cured 1 min. at 240 F. Product is soft, resilient, resistant to laundering and drycleaning.

EXAMPLE 6 An all cotton (garnetted card waste, roving and yarns) carded web weighing about 4 oz./sq. yd. is impregnated with an aqueous dispersion obtained from the triethy1 amine-neutralized product of Example X diluted to a concentration of 1.0% and containing 0.08% of benzyldimethyloctadecylammonium chloride at ca. 500% wet pick-up. Dried and cured 5 min. at 240 F. Product has good coherence, porous, soft, textile hand.

EXAMPLE 7 An all nylon (50% 10-denier, 50% 3-denier, all 1.5 inch staple) random web obtained by air-deposition weighing about 1.25 oz./sq. yd. is impregnated with an aqueous dispersion obtained from the triethylamine-neutralized product of Example Y diluted to a concentration of 1.0% and containing 0.08% of benzyldimethyloctadecylammonium chloride at ca. 700% wet pick-up. Dried 1.5 min. 225 F., cured 3 min. at 350 F. Product is soft, resilient, resistant to laundering and drycleaning.

EXAMPLE 8 An all viscose (5 denier, 1.5 inch staple) carded web weighing about 1.5 oz./sq. yd. is impregnated with an aqueous dispersion obtained from the triethylamine-neutralized product of Example 2 diluted to a concentration EXAMPLE 9 The procedure of Example 1(a) is repeated except that the impregnant is that obtained by the ammonia-new tralization of the condensation product of Example N diluted to a solids concentration of 0.5% in onecase, 1.2% in another, and 2% in a third. Porous, coherent, flexible products resistant to laundering and dry-cleaning are obtained.

Products obtained in the same way from dispersions of the condensates of Examples 0, Q, R and S have quite similar properties of porosity, flexibility and resistance to laundering, scouring, and dry-cleaning operations It is to be understood that changes and variations may be made without departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. As an article of manufacture, a non-woven fibrous product in which the fibers are distributed in random array, fibers in the product being bonded together by a binder comprising an infusible heat-cured product of a salt, formed by at least partial neutralization with a member selected from the group consisting of ammonia, volatile amines, and quaternary ammonium compounds, of a condensation product of (l) 40 to 60 parts by weight of an organic solvent-soluble (C -C )-alkylated condensate of formaldehyde with a compound selected from the group consisting of urea, thiourea, imidazolidinone-Z, acetoguanarnine, benzoguanamine, melamine, and monoand di-(C C.,)alkylmelamines with (2) 40 to 60 parts by weight of a polyester having an average molecular weight of about 800 to 1500 containing hydroxyl groups, free carboxyl groups, and an acid number between about and about 100, the polyester being a condensation product of an aromatic member selected from the group consisting of o-phthalic acid, o-phthalic acid containing lower alkyl substituents in the ring and their anhydrides with a condensation product selected from the group consisting of (a) polyesters having an acid value of not over 10 and obtained from the condensation of a mixture .of at least one dibasic aliphatic acid having 5 to 10 carbon atoms with a polyol material containing at least 25 mole percent of at least one polyol containing at least three hydroxyl groups, the proportions in the mixture being 'in the range of 1.2 to 1.8 moles of 'polyol to each mole of acid, and (b) polyesters as obtained in (a) but modified by condensation with-a fatty acid having 8 to 30 carbon atoms; the proportion of the aromatic member to the total polyol material being in the range of 2 to 3.5 moles of the former for each 3 moles of the latter.

2. An article of manufacture as defined in claim 1 in which said polyol consists entirely of one or more polyols having at least three hydroxyl groups.

3. An article of manufacture as defined in claim 1 in which said polyol is trimethylolethane.

4. An article of manufacture as defined in claim 1 in which said polyol is pentaerythritol.

5. An article of manufacture as defined in claim 1 in which said polyol is glycerol.

6. An article of manufacture as defined in claim 1 in which said polyol is trimethylolethane and the dibasic aliphatic acid is adipic acid.

7. An article of manufacture as defined in claim 1 in which said polyol is trimethylolethane and the dibasic aliphatic acid is sebacic acid.

8. An article of manufacture as defined in claim I in 19 which said polyol is trimethylolethane and the dibasic aliphatic acidis adipic acid and the. polyester is modified by lauric acid.

9. An article of manufacture as defined in claim 1 in which said polyol is trimethylolethane and the dibasic aliphatic acid is adipic acid and the polyester is modified by the acid of soybean oil.

7 10. As an article of manufacture, a non-woven fibrous product-,in which the fibers are distributed in random array, fibers in the product being bonded together by a binder compris ng an infusible heat-cured product of a salt, formed by at least partial neutralization with a member selected from the group consisting of ammonia, volatile amines, and quaternary ammonium compounds, of a condensation product of (A) a polyester having an average molecular weght of about 800 to 1500 containing hydroxyl groups, free ca'rboxyl groups, and an acid number between about 90 and about 100, the polyester being a condensation product of an aromat c member selected from the group consisting of' o-phthalic acid, o-ph'thalic acid containing lower alkyl substituen'ts in the ring and their anhydrides with a condensation product selected from the g'roup'consisting of (a) polyesters having an acid 'valu'epf not over 10 and obta ned from the condensation of a mixture of at least one dibasic aliphatic acid having to' carbon atoms with a polyol material containing at least 25 mole percent of at least one polyol containing at least three hydroxyl groups, the proportions in the mixture being in the range of 1.2 to 1.8 moles of polyol to each mol of acd. and (b) polyesters as obtained in (a) but modified by condensation with afatty acid having 8 to'30 carbon atoms; the proportion of t e aromatic member to the total polyol material being in the range of 2 to 3.5 moles of the former for each 3 moles of the latter, (B) an organic solvent-soluble (C -C )-alkylated condensate of formaldehyde with a compound selected from the group consisting of urea, thiourea, imidazolidnone-Z, acetoguanamine, benzoguanamine, melamine, and monoand di-(C -C alkylmelamines, and (C) an alkyd.

11. An article of manufacture as defined in claim 10 in which the condensation product is formed of 40 to 60 parts of component A for each 50 parts of the condensation product of components B and C and the latter condensation product is formed of about 20 to 30 parts of B to 20 to 30 parts of C.

12. As an article of manufacture, a non-woven fibrous product in which the fibers are distributed in random array, fibers in the product being bonded together by a binder comprising an infusible heat-cured product of a salt, formed by at least partial neutralization with a member selected from the group consisting of ammonia, volatile amines, and quaternary ammonium compounds, of a condensation product of 5.0 parts by weight of the reaction product of an (.1') alkyd and (2) an organic solvent-soluble (C C )-alkylated condensate of formaldehyde with a compound selected from the group consisting of urea, thiourea, imidazolidinonc-Z, acetoguanamine, benzoguanamine, melamine, and monoand di- (C C )alkylmela'mines with (3-) 40 to parts by weight of a polyester having an average molecular weight of about 800 to 1500 containing hydroxyl groups, free carboxyl groups, and an acid number between about and about 100, the polyester being a condensation product of an aromatic member selected from the group consisting of o-phthalic acid, o-phthalic acid containing lower alkyl substituents in the ring and their anhydrides with a condensation product selected from the group consisting of (a) polyesters having an acid value of not over 10 and obtained from the condensation of a mixture of at least one dibasic aliphatic acid having 5 to 10 carbon atoms with a polyol material containing at least 25 mole percent of at least one polyol containing at least three hydroxyl groups, the proportions in the mixture being in the range of 1.2 to 1.8 moles of polyol to each mole of acid, and (b) polyesters as obtained in (a) but modfied by condensation with a fatty acid having 8 to 30 carbon atoms; the proportion of the aromatic member to the total polyol material being in the range of 2 to 3.5 moles of the former for each 3 moles of the latter.

13. An article of manufacture as defined in claim 12 in which the salt is a quaternary ammonium salt.

14. An article of manufacture as defined in claim 12 in which the salt is an ammonium salt.

15. An article of manufacture as defined in claim 12 in which the salt is an amine salt.

16. An article of manufacture as defined in claim 12 in which the salt is a tricthylamine salt.

17. An article of manufacture as defined in claim 16 in which the polyol is trimethylolethane and the dibasic aliphatic acid is adipic acid and the polyester is modified by lauric acid,

18. An article of manufacture as defined in claim 17 in which the aminoplast is a butylated polymethylolmelamine and the alkyd is a coconut oil-modified glycerol phthalate.

19. An article of manufacture as defined in claim 16 in which the polyol is trimethylolethane, the dibasic acid is adipic acid, the polyester is modified by soybean oil acids, the alkyd is a linseed oil-modified glycerol phthalate, and the aminoplast is a butylated polymethylolmelamine.

References Cited in the file of this patent UNITED STATES PATENTS 2,629,701 Ericks b Feb. 24, 1 953 2,720,500 Cody a Oct. 11, 1955 2,765,287 Aycock Oct. 2, 1956

Claims (1)

1. AS AN ARTICLE OF MANUFACTURE, A NON-WOVEN FIBROUS PRODUCT IN WHICH THE FIBERS ARE DISTRIBUTED IN RANDOM ARRAY, FIBERS IN THE PRODUCT BEING BONDED TOGETHER BY A BINDER COMPRISING AN INFUSIBLE HEAT-CURED PRODUCT OF A SALT, FORMED BY AT LEAST PARTIAL NEUTRALIZATION WITH A MEMBER SELECTED FROM THE GROUP CONSISTING OF AMMONIA, VOLATILE AMINES, AND QUATERNARY AMMONIUM COMPOUNDS, OF A CONDENSATION PRODUCT OF (1) 40 TO 60 PARTS BY WEIGHT OF AN ORGANIC SOLVENT-SOLUBLE (C3-C6)-ALKYLATED CONDENSATE OF FORMALDEHYDE WITH A COMPOUND SELECTED FROM THE GROUP CONSISTING OF UREA, THIOUREA, IMIDAZOLIDINONE-2, ACETOGUANAMINE, BENZOGUANAMINE, MELAMINE, AND MONOAND DI-(C1-C4)ALKYLMELAMINES WITH (2) 40 TO 60 PARTS BY WEIGHT OF A POLYESTER HAVING AN AVERAGE MOLECULAR WEIGHT OF ABOUT 800 TO 1500 CONTAINING HYDROXYL GROUPS, FREE CARBOXYL GROUPS, AND AN ACID NUMBER BETWEEN ABOUT 90 AND ABOUT 100, ATHE POLYESTER BEING A CONDENSATION PRODUCT OF AN AROMATIC MEMBER SELECTED FROMTHE GROUP CONSISTING OF O-PHTHALIC ACID, O-PHTHALIC ACID CONTAINING LOWER ALKYL SUBSTITUENTS IN THE RING AND THEIR ANHYDRIES WITH A CONDENSATION PRODUCT SELECTED FROM THE GROUP THE CONSISTING OF (A) POLYESTERS HAVING AN ACID VALUE OF NOT OVER 10 AND OBTAINED FROM THE CONDENSATION OF A MIXTURE OF AT LEAST ONE DIBASIC ALIPHATIC ACID HAVING 5 TO 10 CARBON ATOMS WITH A POLYOL MATERIAL CONTAINING AT LEAST 25 MOLE PERCENT OF AT LEAST ONE POLYOL CONTAINING AT LEAST THREE HYDROXYL GROUPS, THE PROPORTIONS IN THE MIXTURE BEING IN THE RANGE OF 1.2 TO 1.8 MOLES OF POLYOL TO EACH MOLE OF ACID, AND (B) POLYESTERS AS OBTAINED IN (A) BUT MODIFIED BY CONDENSATION WITH A FATTY ACID HAVING 8 TO 30 CARBON ATOM; THE PROPORTION OF THE AROMATIC MEMBER TO THE TOTAL POLYOL MATERIALS BEING THE RANGE OF 2 TO 3.5 MOLES OF THE FORMER FOR EACH 3 MOLES OF THE LATTER.