US3188291A - Detergent compositions and granules and method of making them - Google Patents

Description

United. States Patent 3,188,291 DETERGENT CGMPOSITHGNS AND GRANULES AND METHOD 0]? MAKHQG THEM Harry 3. Hugues, Upper Darby, and George D. Evans, lll', Broomall, Pa, assignors, hy mesne assignments, to Purex Corporation, Ltd, a corporation of California No Drawing. Filed Dec. 23, 1959, Ser. No. 81,451

12 Claims. (61. 252-117) This invention relates to detergent compositions and such compositions in the form of granules as well as methods of making such compositions and granules and also to carrier compositions useful in making such compositions by the addition thereto of soap builders and additives.

Most synthetic detergent compositions popularly marketed today are produced by a spray drying technique which results in a homogeneous hollow sphere or bead. Such synthetic detergent bead has the advantage of a good hard water performance, rapid solubility, and low bulk density (approx. 20 lbs/cu. ft.).

The disadvantages of such process include high initial investment for the spray drying equipment and a higher percentage (3060%) of water is necessary to form a suitable slurry for pumping, atomizing and general processing prior to drying. In adidtion, the synthetic detergent compositions very seldom contain soap because of its poor performance characteristics in hard water (i.e., lime soap scum formation) even though it is well known that soap is an excellent detergent.

Among the objects of the present invention are included the production of a homogeneous detergent granule composition desirably in particulate form by spraysolidifying a molten carrier composition containing soap builders and additives to granules of low bulk density, performing effectively even in hard water solution both at wash and rinse dilutions.

Other objects include the production of carrier compositions useful for such purposes by addition thereto of soap builders and soap additives.

Further objects include methods of producing such compositions and granules.

Still further objects and advantages will appear from the more detailed description given below, such description being by way of illustration and explanation, and not limitation, since various changes may be made therein by those skilled in the art without departing from the spirit and scope of the present invention.

In accordance with the present invention, a carrier composition which is molten when heated and solidifies upon cooling is produced, to which carrier the necessary and conventional soap builders and soap additives may he added, together with limited quantities of Water, and is convertible to low bulk density particulate form on cooling. Particulate form may be defined as bead, granule or powder of which as much as 95% or more will pass through a standard 10 mesh per inch sieve. The composition must be pumpable while hot and capable of being atomized at high pressure into the solid particulate form of low bulk density on cooling. Low bulk density may be here defined as from about 1 to 30 lbs/cu. ft.

The invention overcomes the difliculties of prior art processes.

and pumps. No heated towers are required with hot air necessary to dry the slurry of 30 to 60% moisture content down to 10% moisture, since the detergent compositions of the present invention have a maximum water content of less than about 15%, and only at most 1 to water is lost by evaporation during atomization. The spray operation is more properly a spray solidifying step per se Viscos ity pressure (lbs/sq.

The equipment required is readily available a in soap making plants including heated crutchers, valving' 3,188,291 Patented June 8, 1965 "ice than a drying operation which latter is however required in prior art processes. These features of the present invention are due in part to the fact that soap is a necessity in the present invention for both processing and good detergency. I

The carrier substance or vehicle should have the following properties: the material should be water soluble or dispersible; it should melt at F. or higher, ideally it should be a detergent or have no detrimental effect on detergency, and should crystallize rapidly on cooling. The carrier composition found most efiective consists essentially of a mixture of a sodium fatty acid soap and a monoalkylolamide. The sodium soap may be manufactured from fatty acids or mixtures of fatty acids, or oils or mixtures of oils, or mixtures of fatty acids and oils, the latter being glycerides of fatty acids of desirably from about twelve to eighteen or more carbon atoms, including such fatty acids as lauric, myristic, palmitic, oleic, stearic, etc. Representative oils are tallow, cottonseed oil, coconut oil, palm kernel oil and tall oil, or mixtures of them; tallow and coconut oil being preferred.

The monoalkylolamide of a fatty acid includes such amides from monoalkylolamines particularly lower alkylols such as monoethanol amine, monoisopropanolamine, monobutanolamine, etc., monoglycerylamine etc. The fatty acid in the amide desirably has from 8 to 14 carbon atoms.

The carrier composition consists essentially of any of the soaps or mixtures thereof as given above with an alkylolamide or mixtures thereof as set forth above. The carrier composition preferably contains ratio of soap or soaps to amide or mixtures of amides of from 1:1 to 12:1 by weight. Such carrier compositions perform the usual function of acting as a vehicle for the incorporation of soap builders and soap additives and also as an effective lime (or magnesia) soap dispersant both at use dilution and rinsing dilution of the resultant particulate dispersion.

It has been found that 37-40% anhydrous soap (and no amide) in combination with 15% or less water, the remainder being a composition of typical inorganic build ers (i.e., detergency aids) such as sodium tripolyphosphate, tetra sodium pyrohosphate, sodium silicate, sodium carbonate and sodium bicarbonate, is the minimum carrier that can be processed into particulate form without an additional vehicle. If more than 15% Water is included in the particulate detergent, a moist, tacky particle results on atomization. Illustrating some of these matters, the following examples are given.

TABLE I Examples 1 2 3 4 5 Coconut fatty acid monoethanolamide, percent Anhydrous soap, percent Glycerine, percent Sodium silicate, percent Tetra sodium pyrophosphate, percent Sodium tripolyphosphate,

percent Sodium carbonate, percent. Moisture, percent Crutcher temp, F 210 Aton)1ization press (lbs./sq./

Bulk density (lbs/cu. ft.)

l Viscosity of the detergent mix prior to atomization is expressed as the pressure developed by a standard high pressure pump when freely circulating the detergent nux.

2 Coarse heavy chip.

In connection with Table I, the following comments may be noted.

In Example 1, 34% anhydrous soap is not sufficient carrier for incorporation of the builders and an unpumpable, extremely viscous, non-workable soap mass results. Obviously, if the water content were increased, the viscosity would decrease suificiently for efiicient working but on atomization the resultant particles would be wet and tacky. In Examples 4 and 5, an easily pumpab-le, medium viscosity detergent mass results, which can be atomized int-o particulate form.

The equipment used in the present invention is similar to that used in Coyle Patent US. 2,823,187 with one important exception, the high pressure pump must be capable of delivering the molten detergent for atomization at pressures of 8,000-12,000 lbs/sq. in. Thus in Example 2, in which a minimum of soap is used, and in Example 4, in which amide is incorporated, when atomizing at a pressure of 5,000 lbs/sq. in. a coarse, heavy chip results. However, when the pressure is increased to 9,000 lb-s./ sq. in. (Examples 3 and 5), a fine particle results in the desired bulk density range.

In the carrier compositions as given above, a supplemental carrier component'may be included with the soap and amide. Such supplemental carriers that may thus be used are solid, water soluble polyethylene oxide and polypropylene oxide =condensates (cg. Carbow-ax 4000 and 6000) solid nonionic detergents (e.g. Plunonic F-68 and Tetronics 707 and 908, Igepal DJ-970), and solid glycol or polyglycol esters (e.g. diethylene glycol stearate, glycerol monostearate). Thus, many of the most eiiective detergents are ternary mixes of soap, monoalkylolamides, and an additional carrier. Pluronic F-68 is a condensate of polypropylene oxide and ethylene oxide, the polypropylene oxide group having a molecular weight Within the range 1501 to 1800 and the condensate containing 80 to 90% by weight of ethylene oxide.

Examples 6-14 of Table II illustrate some of the variations possible in the carrier both as to type and amount. In general, total carrier is the minimum for incorporation of the inorganic builders and additives, while represents a desirable upper limit for processing. The formulations in the examples were handled as a hot, molten slurry on mixing and atomized under high pressure with resultant cooling into particles.

Further examples are the following:

Pluronic F-68 Anhydrous soap Sodium silicate Sodium tripolyphosphate- Sodium tetrapyrophosphate Sodium carbonate Water and volatile CMC, optical dye, perfume ct Where the multicomponent carrier is used, the 25% total carrier minimum includes the amounts, of soap, amide, and supplemental solid carrier vehicle, ratios of which may be soap from 10 to 18%, amide from 4 to 10%, and supplemental carrier from 0 to 10%, all by weight.

The viscosity pressure of the detergent mix plays an important part in the bulk density of the atomized particle. If the viscosity pressure is above 2400 lbs/sq. in., the mix is too heavy and viscous for processing and atomization. If the viscosity pressure falls below 1200 lbs/sq. in., in a particle results which is of high bulk density. The optimum range of viscosity pressure is 1600-2000 lbs/sq. in. The following examples are illustrative of the effect of viscosity pressure on bulk density. The formulation used is that of Example 11.

1 Coarse heavy chip.

While Examples 6l6 indicate the formulation requirements for processing into particulate detergent form, it is necessary that the resultant detergent perform successfully in hard water. It is in this additional respect that the anhydrous soap-monoalkylolamide combination is necessary.

It is well known that carboxylic acid soaps react in solution with metal ions to form an insoluble metal soap that precipitates as a scum. The metal ions that form this scum are mainly those of calcium and magnesium which appear in most water supplies. In this invention, this undesirable lime soap scam is dispersed finely by the mon0- alkylolamide so as not to deposit on washed clothes or onto the washing machine. It is essential that this dispersion be effective in the wash cycle but also on rinsing where high dilution often reduces the efficiency of the dispersing agent.

Test procedure referred to herein used a front-loading commercial washing machine of 6 gallon water capacity in both the wash and rinse cycle. A standard six pound load of cotton .sheetswas used as ballast and for hard water testing 300 ppm. (as CaCO hard water was used. Observations were made after ten minutes in the wash cycle and at the completion of the rinse. Often, a black cotton cloth was fastened to the inside of the Washer basket so that on ejection of the wash water, the degree of lime soap dispersion could be evaluated. If the black cloth after the wash or rinse cycle was matted with lime soap scum, poor dispersion had occurred; if the black cloth was clear, excellent dispersion had occurred. The detergent mix a was used. at .25 concentration in the wash water of 120 F. temperature. In the following examples, laboratory TABLE II Examples 6 7 8 9 1 11 12 13 14 Percent Percent Percent Percent Percent Percent Percent Percent Percent Laurie acid monoethanolamide 4. 0 Palm kernel fatty acid monoethanolamide 4. 2 Coconut fatty acid monoethanolamide 4. 0 4. 83 7. 00 5. 25 5. 25 Anhydrous soap 11 9 1 -9 12.0 15. 00 21.20 21. 20 Glycorine 12 42 68 68 Glyeeryl monostear 8. 41 Carbowax 6000 5. 4 Carbowax 4000 3. 5 "Plurom'c" F-68 6. 1 7. 7. 80 8. 41 Igepal DJ-970 9. 2 9. 2 Sodium silicate 5. 0 1 5. 0 9 5. 10 5. 10 5. 10 5,10 Tetra sodium pyrophosphate 9. 0 39. 0 9. 0 48. 9 8. 22 8. 22 11. 25 11. 25 Sodium tripolyphosphate 35. 5 35. 5 41. 40 35. 8O 25. 51 25, 51 Sodium carbonate. 15. 0 l4. 6 15. 0 15. 1 13. 69 14. 39 15. 30 15. 30 Water and volatile 9. 8 11. 5 9. 8 10. 0 0. 14 5. 57 7. 30 7. 30 CMO, optical brighteners, perfume. .6 .6 .7 .70

formulation of Example 11 was used with variation in the dispersant. was 1700 lbs./ sq. in. (if the pressure is too high at this TABLE IV Example 2O 21 22 23 24 Dispersant Laurie monoisopro- Laurie monoethanol- Palm kernel fatty Coconut fatty acid None,

panolamide. amide. acid monoethanolmonoethanolamide.

amide. Wash water Foam, well dispersed Foam, well dispersed Foam, well dispersed Foam, well dispersed Heavy nondispersed curd. curd. curd. curd curd. Rinse water Clear Clear Clear (tear Turbid. Black clo h do Matted white curd.

In the following examples, the actual particulate form detergent is used to illustrate the lime soap dispersing properties of the monoalkylolamide.

TABLE V Example 25 26 27 28 29 30 Formulation (Example Number) 2 5 ll 12 12 16. Wash water Heavy, non-dis Foam, Well dis- Foam, well (lis- Foam, well dis- Foam, well dis- Foam, well dispersed curd. persed curd. persed curd. parsed curd. persed curd. persed curd. Rinse water Turbid, small (leer r Cl ar Clear 7 Slightly turbid but fioeculent scum dispersed.

Below are two examples to illustrate the compounding and mixing:

N0 supplemental carrier To 50 lbs. of tallow and 91 lbs. of tallow fatty acids heated to 130 F. in a jacketed crutcher, is added 101.5 lbs. of 21.2% sodium hydroxide solution (200 F.) and the mix is thoroughly stirred for 15 minutes. To this mix is then added 25 lbs. of molten coconut fatty acid monoethanolamide. This addition makes the mix very fluid. The following powdered additives are then added in the order listed: 100 lbs. sodium tripolyphosphate, 74.5 lbs. sodium carbonate, 39 lbs. sodium metasilicate, 44 lbs. tetrasodium pyrophosphate. This entire mix is crutched for 10 minutes with sufiicient heat on the jacketed crutcher to maintain the temperature at 210 F.

The water content was determined at this point and found to be 15.0%. The batch was then atomized as indicated in Examples 4 and 5. Since the water content of the atomized material is 13.5%, only 1.5% water was lost through evaporation.

With supplemental carrier To 118.5 lbs. of tallow fatty acid heated to 130 'F. in a jacketed crutcher, is added 51 lbs. of molten Pluronic F-68. To this mix is added 84.75 lbs. of 24.4% sodium hydroxide solution (175 F.). This mix is thoroughly stirred for 10 minutes to complete saponification. To this mix is then added 31.75 lbs. of coconut fatty acid monoethanolamide with good stirring. The following powdered additives are then added in the order listed: 183.5 lbs. sodium tripolyphosphate, 97.5 lbs. soda ash, 32.5 lbs. sodium metasilicate, and 71.75 lbs. tetrasodium pyrophos phate. The entire mix is then crutched for 10 minutes at 210 F. prior to atomization.

It is important that the amide and ester type carrier be added after completion of saponification so as to prevent hydrolysis.

The water content of the material in the crutcher was ticulate form detergent was formed with the following formula and characteristics:

in the tallow fatty acid.

Having thus set forth our invention we claim:

1. A carrier composition for synthetic detergents consisting essentially of a mixture of a sodium soap of a fatty acid having from 12 to 18 carbon atoms, with a mono- (lower alkylol)amide of a fatty acid having from 8 to '14 carbon atoms, the ratio of soap to alkylolamide being from 1:1 to 12:1 by weight.

2. The carrier composition of claim 1 in which the fatty acid of the amide is lauric acid.

3. A carrier composition for synthetic detergents consisting of the carrier composition of claim 1 including from about 2 to 13 by weight based on the weight of the total composition, of a supplemental solid carrier vehicle of an organic synthetic non-ionic detergent.

4. A synthetic detergent composition consisting essentially of the carrier composition of claim 3 in an amount of from about 25 to 35% water below about 15%, and the balance being inorganic soap builders, the percentage being by weight based on the weight of the total composition, the composition having a viscosity pressure above about 1200 lbs./ sq. in. but not above about 24001bs./sq. in., the composition being pumpable when hot and solid at room temperature.

7 5. Particulate spray solidified particles of the composition of claim 4.

6. A synthetic detergent composition consisting essentially of the carrier composition of claim 1 in an amount from about 25 to 35%, water not exceeding 15%, and the balance being inorganic builders, the percentages being by weight based on the weight of the total composition, the composition having a viscosity pressure above about 1200 lbs/sq. in. but not above about 2400 lbs./ sq. in.

7. Particulate spray solidified particles of the composition of claim 6.

8. The method of making a synthetic detergent composition which consists essentially in admixing a carrier composittion as set forth in claim 1 with water and soap builders to give a composition having a viscosity pressure above about 1200 lbs/sq. in. but not above about 2400 lbs./ sq. in.

9. The method of claim 8 in which the detergent composition is spray solidified from molten condition at a pressure above about 5000 lbs/sq. in. but below about 29.5%, glycerine 1.2%, earring the following components in intermixture therewith: sodium silicate 7.8%, tetra sodium pyrophosphate 8.6%, sodium tripolyphosphate 19.7%, sodium carbonate 14.7%, and moisture 13.5%.

12. A synthetic detergent composition consisting essentially of the following components in proportions by weight: a carrier composition of cocoanut fatty acid monoethanolamide 5%, a condensate of polypropylene oxide and ethylene oxide the polypropylene oxide group having a molecular weight within the range 1501 to 1800 and the condensate containing to by weight of ethylene oxide 7%, anhydrous sodium fatty acid soap 45% carrying the following components in intermixture therewith: sodium silicate 5% sodium tripolyphosphate 25.4%, Water and volatile 12%, balance optical dye, perfume.

References Cited by the Examiner UNITED STATES PATENTS 2,746,931 5/ 56 Vitale et al. 2,861,954 11/58 Ruff 252 3,930,760 3/60 Gebhardt 252--1 17 XR OTHER REFERENCES Alrosol Technical Bulletin, Alrose Chemical Co. (-1946), pages 1-4.

Zussman et al., Soap and Sanitary Chemicals, April 1950, pages 37-40, 141.

JULIUS GREENWALD, Primary Examiner.

Claims (1)

1. A CARRIER COMPOSITION FOR SYNTHETIC DETERGENTS CONSISTING ESSENTIALLY OF A MIXTURE OF A SODIUM SOAP OF A FATTY ACID HAVING FROM 12 TO 18 CARBON ATOMS, WITH A MONO(LOWER ALKYLOL)AMIDE OF A FATTY ACID HAVING FROM 8 TO 14 CARBON ATOMS, THE RATION OF SOAP TO ALKYLOLAMIDE BEING FROM 1:1 TO 12:1 BY WEIGHT.