Diamine containing softener compositions
United States Patent Renold DIAMINE CONTAINING SOFTENER COMPOSITIONS Adolph Renold, Somerset. NJ.  
 Colgate-Palmolive Company. New York N.Y.  
 Filed: Oct. 25, 1972 Appl. No.: 300,580  
 Inventor:  
 Assignee:  
 US. Cl. 252/88; 260/78 SC Int. Cl D06m 1/14 Field of Search 252/8.8; 260/78 SC Apr. 22, 1975 3.632.420 l/l972 Kuhn 252/8.8 X  
 Primary E.\&#39;uminerStephen .l. Lechert, Jr. Anurney. Agent or FirmHerbert S. Sylvester;  
 Murray M. Grill; Norman Blumenkopf [57] ABSTRACT The color and odor of technical N-alkyl (C -C )-l. 3-propylene diamines may be improved by treating the diamine with acrylic acid and/or methacrylic acid monomer, after which the monomer is polymerized and neutralized. The addition of small amounts of urea and/or sugar to the treated N-alkyl-l, 3- propylene diamine further improves the fabric softening properties of the diamines and reduces fabric discoloration.  
 4 Claims, N0 Drawings DIAMINE CONTAINING SOFTENlER COMPOSITIONS BACKGROUND OF THE INVENTION This invention relates to methods for improving the color. odor. and fabric softening properties of N-higher alkyl-l. 3-propylene diamines. and of fabric softening compositions incorporating the improved N-higher alkyl propylene diamines.  
  The use of synthetic detergent compositions in heavy-duty household laundering has become a widespread practice. The formulations conventionally employed generally comprise synthetic detergent surfactants and alkaline builder salts which function to enhance the cleaning levels of synthetic materials. Some inorganic builder materials present in detergent formulations have been known to have a tendency to react with the metal ions present in the washing solution. pre cipitating out insoluble salts which deposit on the textile material being laundered. Such deposited mineral salts give the laundered fabrics, a poor. boardy feel particularly at those areas of the fabric which are exposed to frictional and creasing effects such as collars and cuffs. This poor hand oflaundered fabrics and resulting discomfort during use have in part resulted in the creation of a large and expanding market for softener formulations capable of improving the softness or hand&#34; of laundered textiles. It has been found that the treatment of such materials with softening agents improves their softness of feel and may prolong the useful life of the textile materials. In addition. it has been found that such treatment generally results in a fabric having a reduced tendency to accumulate electrical charges. which fact facilitates the ironing of treated materials.  
  N-higher alkyl-l. 3propylene diamines are well known softening agents and are compatible with most synthetic detergent formulations. However. heretofore they have not won much acceptance for use as fabric softeners. because the generally available technical grade N-higher alkyl- 1 3-propylene diamines are characterized by an unpleasant odor which cannot be masked by the detergent perfumes currently available.  
  Additionally, the technical grade N-higher alkyl-l. 3-propylene diamines have a tendency to discolor synthetic fabrics such as polyamides. polyesters. and the like, in regular household laundry; this discoloration darkens upon aging. The best explanation for the discoloration is that it is a heavy metal (e.g. iron) catalyzed decomposition of the diamine. which is a known heavy metal scavenger and used as such in the oil industry.  
  Presently, one of the best known methods for improving the properties of technical grade N-higher alkyl propylene diamines is by vacuum distillation. However. this method is expensive and relatively ineffective: the resulting diamine is not improved signifr cantly. and it is prohibitively expensive for use in detergent formulations. In tergitometer tests using a commercially available laundry detergent. no significant difference between the crude and the distilled diamine was found. Nylon cleaning was particularly poor.  
 SUMMARY OF THE INVENTION It has now been discovered that the properties of technical grade N-higher alkyl-l. 3-propylene diamines, where the alkyl group contains from 12 to 22 carbon atoms. may be significantly improved by treatment with acrylic acid monomer. methacrylic acid monomer. or mixtures of both. and then polymerizing and neutralizing the monomer.  
  Various methods for preparing the N-higher alkyl-l 3-propylene diamines to be treated are known. One method consists in reacting a fatty amine (e.g.. tallow amine or hydrogenated tallow amine) with acrylonitrile and then hydrogenating the reaction product. as shown in the following equations:  
  The resulting diamines have an unattractive color and a malodor characteristic of amines. This color and amine malodor can be reduced. however. by treating the technical diamine with acrylic acid and/or methacrylic acid monomer. polymerizing the monomer. and neutralizing the resulting polymer. The monomer acts as an acidic scavenger by interacting with colorforming impurities. and the alkali polyacrylate. prepared in situ. reduces the heavy metal sensitivity of diamine-containing surfactants.  
  The ratio of N-higher alkyl-l 3-propylene diamine to acrylic acid or methacrylic acid monomer ranges from about 30:1 to about 5:1 by weight.  
  The addition of small amounts of urea or sugar or mixtures of urea and sugar to the treated Nalkyll 3- propylene diamines greatly and unexpectedly improves the softening properties of the diamines. The urea and- /or sugar is present in amounts ranging from about I percent to about 200 percent by weight of the treated diamine.  
  The N-higher alkyl-l. 3-propylene diamines treated according to the present invention are valuable softening agents for textiles and fabrics manufactured from synthetic and natural fibers and blends thereof. inclusive of cellulose. Dacron-cotton blends. nylon. wool. cotton. Orlon. Orlon blends. and the like. The treated diamines may be used as a rinse additive or in conjunction with a suitable laundry detergent in the wash cycle. Where urea and/or sugar are added to the diamine. the resulting mixture can be used in the same manner.  
  Where the treated N-higher alkyl-l. 3-propylene diamines of the present invention are to be used as rinse additives. they may be mixed with compatible solid additives and fillers. such as aluminum silicate. sodium tripolyphosphate. sodium carbonate, sodium sulfate. and the like. The concentration of the treated N-higher alkyl- 1 3-propylene diamine in these compositions can range from about 5 percent to about percent. although a range of between 15 percent and 30 percent is preferred.  
  Additionally. the treated N-higher alkyl-l. 3- propylene diamines may be dispersed or dissolved in suitable liquid systems where a liquid rinse additive is desired. Examples of such liquids include propylene glycol. ethylene glycol. and isopropanol&#39;. the diamine may then be present in amounts ranging from 10% to 95 percent of the total weight of the final formulation. although a range of from about 30 percent to about percent is preferred.  
  The N-higher alkyl-l. 3-propylene diamines treated according to the present invention are particularly well suited for incorporation in detergent formulations. In such detergent formulations the treated diamine comprises from about 1 percent to about percent by weight of the total composition. and preferably from about 5 percent to about 50 percent by weight of the total composition.  
  The detergents containing the treated diamines of this invention can contain any of the usual compatible adjuvants diluents. and additives. including other detergents. for example. anionic. nonionic. or amphoteric synthetic detergents: perfumes. antiredeposition agents. bacteriostatic agents. dyes. fluorescers. brighteners. suds builders. suds depressors. and the like without detracting from the advantageous properties of the composition.  
  The treated N-higher alkyl-l. 3-propylene diamines of the present invention impart the desired degree of softness to textiles treated therewith when utilized in amounts of from about 0.05 percent to about 5 percent. and. preferably. in amounts ranging from about 1 percent to about 3 percent by weight of the fabric.  
  As examples of suitable synthetic anionic detergents there may be cited. for example, the sodium salts of higher alkyl mononuclear aromatic sulfonates such as tl&#39;ie higher alkyl benzene sulfonates containing from to 16 carbon atoms in the alkyl group in a straight or branched chain; the higher alkyl toluene. xylene. and phenol sulfonates; alkyl naphthalene sulfonate. ammonium diamyl naphthalene sulfonate. and sodium dinonyl naphthalene sulfonate.  
  Other anionic detergents are the olefin sulfonates. including long-chain alkene sulfonates. long-chain hydroxy alkane sulfonates or mixtures of alkanesulfonates and hydroxyalkanesulfonates. These olefin sulfonate detergents may be prepared. in known manner. by the reaction of 50;; with long chain olefins (of 8-25. preferably 12-21. carbon atoms) of the formula R&#39;CH=CHR&#34;. where R is alkyl and R&#34; is alkyl or hydrogen. to produce a mixture of sultones and alkenesulfonic acids. which mixture is then treated to convert the sultones to sulfonates. Examples of other sulfate or sulfonate detergents are primary paraffin sulfonates of about l0-20. preferably about 15-20. carbon atoms; sulfates of higher alcohols; salts of alphasulfofatty esters (e.g.. of about l0-20 carbon atoms. such as methylalpha-sulfomyristate or alpha-sulfotallowate).  
  Examples of sulfates of higher alcohols are sodium lauryl sulfate. sodium tallow alcohol sulfate. Turkey Red Oil or other sulfated oils. or sulfates of monoor di-glycerides of fatty acids (e.g.. stearic monoglyceride monosulfate alkyl poly (ethenoxy) ether sulfates such as the sulfates of the condensation products of ethylene oxide and lauryl alcohol (usually having one to five ethenoxy groups per molecule); lauryl or other higher alkyl glyceryl ether sulfonates; aromatic poly (ethenoxy) ether sulfates such as the sulfates of the condensation products of ethylene oxide and nonyl phenol (usually having one to six oxyethylene groups per molecule).  
  Nonionic surface active agents include those surface active or detergent compounds which contain an organic hydrophobic group and a hydrophilic group which is a reaction product of solubilizing groups such as carboxylate or hydroxyl. with ethylene oxide or with the polyhydration product thereof. polyethylene glycol.  
  As examples of nonionic surface active agents which may be used there may be noted the condensation products of alkyl phenols with ethylene oxide. e.g.. the reaction product of isooctyl phenol with about six to ethylene oxide units; condensation products of alkyl thiophenols with 10 to 15 ethylene oxide units; condensation products of higher fatty alcohols such as tridecyl alcohol with ethylene oxide; ethylene oxide addends of monoeste&#39;rs of hexahydric alcohols and inner esters thereof. such as sorbitan monolaurate. sorbitol monooleate and mannitol monopalmitate. and the condensation products of polypropylene glycol with ethylene oxide. Other nonionics include amine oxides. e.g.. lauryl dimethyl amine oxide; sulfoxides and the like.  
  In addition to the treated N-higher alkyl-l 3- propylene diamines and active detergent. detergent formulations prepared according to the present invention may contain one or more water-soluble detergency builder salts. either of the organic or the inorganic type. and preferably alkaline salts.  
  Examples of water-soluble inorganic detergency builder salts are alkali metal carbonates. phosphates. polyphosphates. sulfates. silicates, etc. Specific examples of such salts are sodium potassium. and lithium tripolyphosphates. carbonates. pyrophosphates. orthophosphates. and hexametaphosphates; sodium. potassium. and lithium sulfates; and sodium potassium. and lithium silicates. Examples of organic alkaline detergency builder salts are l) alkali metal aminopolycarboxylates [e.g.. sodium and potassium ethylenediamine tetraacetates. N- (2-hydroxyethyl) nitrilo diacetates];  
 (2) alkali metal salts of phytic acid (e.g.. sodium and potassium phytates see U.S. Pat. No. 2.739.942); (3) water-soluble salts of ethane-l-hydroxy-l. ldiphosphonate (e.g.. the trisodium and tripotassium salts see U.S. Pat. No. 3.159.58l (4) water&#39;soluble salts of polycarboxylate polymers and copolymers (e.g.. homopolymers of itaconic acid. aconitic acid. maleic acid. mesaconic acid. fumaric acid. and methylene malonic acid. and copolymers thereof with other compatible copolymerizable monomers such as ethylene); and mixtures thereof.  
  Because of the added detergent needed to counterbalance the treated N-higher alkyl-l. 3-propylene diamine softener and because softeners tend to be oily materials. the detergents incorporating the diamines treated according to the present invention have a tendency to be lazy. i.e.. they do not flow easily. It was observed that the addition of urea and/or sugar to the treated diamine reduces the oiliness of the softener. Both urea and sugar display softening properties when combined with the diamine. and. additionally, they absorb diamine. Optimum amounts of both. together with the conventional amounts of an anticaking agent such as heat&#39;treated aluminum silicate. yield a detergent with very desirable flow properties.  
  The detergents of the present invention may be formulated as liquids. solids. pastes. gels. etc. The detergents of the present invention can be effectively used for laundering fabrics in water having a temperature from about 60 to about 2 l 2F.. the detergents containing the treated N-higher alkyl-l. 3-propylene diamines exhibiting unusually effective detergency and fabric softening characteristics in both cold and hot water. The detergent composition concentration in the wash water should range from about 0.05 percent to about 0.5 percent by total weight.  
  In washing fabrics. the addition of the fabrics and the detergent composition can be conducted in any suitable conventional manner. Thus. for example. the fab rics can be added to the container or washer either before or after the washing solution is added. The fabrics are then agitated in the detergent solution for varied periods of time. a wash cycle of from 5 to 15 minutes being generally used in the washing cycle of an automatic agitator type washer. After the fabrics are rinsed. they are dried first by spinning and then by contact with air as in a conventional hanging of the fabrics on a clothesline or in an automatic dryer type system.  
  In the preparation of the detergent compositions of the present invention. generally, the organic detergent and the treated N-higher alkyl-l. 3-propylene diamine. the urea and/r sugar. if it is used. as well as the builders and any minor ingredients are incorporated into the composition prior to its conversion into the final form. e.g,. detergent granules. flakes. bar. etc. However. the individual components of the detergent of the present invention can be added in the form of particles or directly as a liquid to produce a liquid detergent composition.  
 DESCRIPTION OF THE PREFERRED EMBODIMENTS The following specific examples illustrate various embodiments of the present invention. It is to be understood. however, that such examples are presented for the purposes of illustration only, and the present invention is in no way to be deemed as limited thereby.  
 EXAMPLE I Seven hundred twenty grams of technical grade N- tallow l. 3-propylene diamine was placed into a hooded tank equipped with steam coils and a stirrer. The diamine was heated to 95C.. and purged with nitrogen for one hour to remove and modify any potentially color causing impurities prior to the polymerization reaction. The temperature of the diamine was kept around 95C., and 0.25 gram mercaptosuccinic acid and 30 grams of methacrylic acid were added. The mixture was stirred under nitrogen for 1 hour. One gram of VAZO (duPont azobisisobutyronitrile catalyst) was added to the mixture. The nitrogen was discontinued. and the mixture was heated slowly. Forty minutes later the temperature of the reaction mixture was 117C., and another 1.0 gram of VAZO was added. Stirring with heat was continued for an hour. Then 18.2 grams of sodium carbonate was added to neutralize the polyacrylic acid; the mixture was kept at about 1 17C. for an hour with stirring to complete the neutralization.  
  The diamine treated as described above was a superior fabric softener because of its reduced tendency to pick up color by combining with heavy metals and traces of tannin-like materials present in tap water.  
 EXAMPLE II A phosphate-based softener formulation for use either in the wash cycle or the rinse cycle is prepared from the diamine treated according to Example 1. One hundred fifty grams of the softener of Example I was heated to 98C. and 28 grams of sugar was added with good stirring. After 5 minutes 115 grams of urea was added with good stirring. The temperature of the mixture was maintained at about 98C. for 20 minutes more.  
  The mixture above was added to 600 grams lowdensity sodium phosphate in a Hobart mixer and stirred for twenty minutes. The homogeneous mixture was passed through :1 mesh sieve and was ready for use.  
 EXAMPLE III A solid fabric softener composition for use in either the wash cycle or the rinse cycle was prepared from the softener of Example I. Five hundred ten grams of technical sodium tripolyphosphate and 2 grams of sodium carbonate were mixed for five minutes. One hundred two grams of the softener of Example I (molten) was added and the combination was mixed for 20 minutes in a Hobart mixer at room temperature. Then 76 grams of urea (8 mesh) and 25 grams of sugar were added. and the total was mixed for 40 minutes in a Hobart mixer at room temperature. Finally, 15 grams of heattreated aluminum silicate anticaking agent was added, and the combination was mixed for fifteen minutes in a Hobart mixer at room temperature. The resulting fabric softener composition was granular and free flowing.  
 EXAMPLE IV A rinse additive was formulated from the following ingredients:  
 Softener of Example I 20 grams Urea 6 grams Synthetic detergent 18% anionic/ 7% sodium silicate/339i sodium phosphate/(L4G C MC 30 grams Technical sodium tripolyphosphate 54 grams Heat-treated aluminum silicate 30 grams Optical brightener 0.4 gram Perfume 0.4 ml.  
  The resulting fabric softener rinse additive had excellent solubility under use conditions and exhibited marginal dusting.  
 EXAMPLE V The following ingredients were heated in a mortar to 4852C.. powdered, cooled to room temperature. passed through an 8 mesh sieve, and ball milled for 2 hours:  
 Softener of Example I 21 grams Sodium carbonate 2] grams Urea 12 grams Heat-treated aluminum silicate 32 grams Carhoxymethylcellulose 12 grams Optical brightener 0.4 grams Perfume 0.4 ml.  
  The resulting rinse additive formulation exhibited good solubility under use conditions and left very little dust on fabrics treated therewith.  
 EXAMPLE VI A detergent composition was prepared based on the fabric softener of Example V as follows:  
 Softener of Example 164 grams Synthetic detergent (109i anionic/27:  
 nonionic/l lr nonionic/339i sodium tripolyphosphate/ISI: sodium silcate 638 grams Perfume 1.2 ml. Optical brighteners 7.2 grams EXAMPLE VII A liquid fabric softener composition was formulated from the following ingredients:  
 Softener of Example I 57 grams Ethylene glycol 25 grams L&#39;rea 3 grams Sugar 2 grams EXAMPLE VIII The following ingredients were placed into a mortar:  
 Softener of Example I 34 grams Sodium carbonate 23 grams Urea l2 grams Heat-treated aluminum silicate grams Carboxymethylcellulose 4 grams Synthetic detergent I071 anionic/29? nonionicll l nonionic/33&#39;/1 sodium tripolyphosphate/7.5 2 sodium silicate) 46 grams The ingredients were placed into a l 10C. oven until warmed to a temperature of 5055C. The mixture was stirred lightly and cooled to room temperature by placing the powder into the freezing compartment of a refrigerator for 45 minutes. The cooled mixture was then passed through a 12 mesh screen. The resulting mixture was uniform and ready for further dilution to a detergent formulation.  
  The mixture was used to prepare a detergent composition as follows:  
 Mixture of softener 87.0 grams Synthetic detergent( [O /l anionic/ 29; nonionic/l&#39;l: nonionicl33 /r sodium tripolyphospate/TSV: sodium silicate) 3|} grams Optical brighteners 8 grams Perfume 2.0 ml.  
 EXAMPLE IX The softeners of the present invention are particularly suitable for use in phosphate-free detergents. A concentrated softener base was formulated as follows:  
 Softener of Example I 34 grams Sodium carbonate 23 grams Urea 12 grams Heat-treated aluminum silicate 23 grams C arboxymethylcellulose 4 grams Low foam synthetic detergent linear dodccyl benzene sulfonate/ 257: silicate/471 ethoxylated fatty alcohol/271 (MC/6V1 soap) 46 grams Softener mixture 87 grams C arboxymethylcellulosc 4 grams Low foam synthetic detergent (25% linear dodecyl benzene sulfonate/lfi /r silicate/471 ethoxylated fatty alcohol/ 27: CMC/o /l soap) 3l3 grams Optical hrightcners 1 gram EXAMPLE X A high foam detergent can be formulated using the softeners of the present invention.  
 The following ingredients were placed into a mortar:  
 Softener of Example I 34 grams Sodium carbonate 23 grams L&#39;rea l2 grams (arboxymethylcellulose 4 grams High foam synthetic detergent (2571 -572 silicate/471 ethoxvlated fatty alcohol/271 C MC ll /l soap 46 grams prepared Softener mixture 87 grams High foam synthetic detergent (25% lnear dodecyl benzene sulfonate/ 25% silicate/4&#39;71 ethoxylated fatty alcohol/2% C MC I71 soap 3 13 grams Optical brighteners 1 gram The N-higher alkyl propylene diamines treated according to the present invention can be used to treat a variety of fabrics, which can be made from natural animal and vegetable fibers and blends of synthetic fibers as well as entirely from synthetic fibers. These include wool. silk. cotton. linen, glass, acetate, rayon, nylon,,  
 Dacron, Orlon, blends of Dacron. e.g., with cotton, 0rlon-wool blends. and the like.  
  Treatment of fabrics with the N-higher alkyl propylene diamines treated according to the present invention is especially advantageous where it is desired to overcome hardness of feel or to enhance softness to touch and minimize fabric yellowing. Advantages realized herewith are softer, fluffier towels. smoother. silkier sheets and pillowcases, longer garment life. and a whiter and/or brighter fabric.  
  Although the present invention has been described with reference to particular embodiments and examples, it will be apparent to those skilled in the art that variations and modifications of this invention can be made and that equivalents can be substituted therefore without departing from the principles and true spirit of the invention.  
 What is claimed is:  
 l. A fabric softening composition comprising 1. N-higher alkyl-1,3-propylene diamine said higher alkyl group having from l222 carbon atoms and having been treated by contacting same with a monomer selected from the group consisting of acrylic acid. methacrylic acid, and mixtures thereof. polymerizing the monomer and neutralizing the polymerized monomer.  
 2. an additive, said additive selected from the group consisting of urea. sugar. and mixtures thereof.  
  2. The fabric softener composition of claim 1 wherein said additive is present in amounts ranging from about 1 percent to about 200 percent of the total composition by weight.  
  3. The fabric softener composition of claim 2 wherein said additive is urea.  
  4. The fabric softener composition of claim 1 wherein said additive is urea.