Application of Arno Cahn, Mark D. Konort and Jerome Rudy

399 F.2d 236, 55 C.C.P.A. 1422

• Court: Court of Customs and Patent Appeals
• Decided: July 3, 1968
• Docket: Patent Appeal 7985
• Status: Published

Opinion

WORLEY, Chief Judge.

The sole issue here is whether the Board of Appeals committed reversible error in sustaining the examiner’s rejection of claims 1, 4-7, 12, 17 and 18 1 as unpatentable in view of certain prior art under 35 U.S.C. § 103.

The invention relates to soap compositions for use in hard water. Appellants’ specification provides the following background:

One of the major disadvantages attending the use of soap as a detergent is the water-insoluble precipitates which the soap forms with hardness ions present in hard water. The water-insoluble soap “curd” thus formed detracts from the detergent action of the soap and forms an unsightly scum on the surface of the washing solution. On rinsing, the scum forms a deposit upon the skin and upon the containers employed for the washing operation, such as bathtubs, sinks, washing machines and the like. The presence of this material is objectionable and in effect results in incomplete cleaning.

The problem of preventing lime soap formation is a fairly complex one. When a water-soluble soap is added to hard water, the soap combines with calcium and magnesium ions and precipitates as a water-insoluble calcium and magnesium soap. As long as the concentration of soap in the solution remains above the foaming level, or if non-soap detergents are present at a concentration sufficient to provide a foaming action, the water-insoluble lime soaps remain fairly well dispersed. However, when the solution is diluted as by rinsing to the extent that the foaming and dispersing power of the water-soluble soap and/or detergent disappears, the lime soaps precipitate to form a sticky and unsightly surface scum. In the usual washing process, the dilution is carried out with water containing additional hardness ions so that additional lime soaps may be formed. * * *

It is known that alkylbenzene-sulfonates, the alkyl chain of which is of the normal straight chain type, will disperse lime soaps and improve the lathering of soap in hard water. Al-kyl aryl sulfonate mixtures produced by sulfonating various petroleum fractions have been suggested for this purpose. [Emphasis supplied.]

According to appellants, those straight chain, normal alkylbenzenesulfonates are effective dispersants only when employed at concentrations of 50-65%. At that high concentration, however, the mixtures are said to be “too sticky or tacky to process economically” in the usual milling and plodding (extruding) machines used in the manufacture of soap bars. While starch has been used to reduce the stickiness problem, “the difficulties have not been entirely overcome.”

As their solution to the problem, appellants combine a conventional water-soluble soap, viz. an alkali metal salt of certain higher fatty acids, with 10-30% based on the weight of soap of alkali metal and alkaline earth metal salts of certain alkylbenzenesulfonic acids. The sulfonates are prepared by alkylating benzene with a mixture of alpha-olefins of the formula CHg(CH2)„CH=CH2, where n=9-15. The alkylbenzenes are sulfonated to produce alkylbenzene-sulfonic acids which in turn are neutralized to produce the desired salt. In addition to producing alkylbenzenes of varying alkyl chain length, the alkylation reaction yields a mixture of isomers in which the benzene ring is attached to various internal carbon atoms of any given alkyl chain, as illustrated by the formula in claim 1 reproduced below. At the concentrations employed, the al-kylbenzenesulfonates utilized by appellants are said to avoid the processing problems and to impart lime-soap dispersing properties “considerably superior” to like properties imparted by straight chain, normal alkylben-zenesulfonates of the formula CHs— (CH2)n-C6H4-S03M, where the alkyl group is attached terminally, not internally, to the benzene ring. The compositions may also contain various conventional adjuvants, such as free fatty acids, perfume and the like.

Claim 1 is illustrative:

A composition consisting essentially of a water-soluble soap and a salt of a mixture of sulfonated aryl-substituted alkanes of the formula wherein n is a

whole number from 9 to 15, m is zero to to-1 where n is an odd number and 2 m is zero to n where n is an even ~Y

number, the salt being selected from the group consisting of alkali metal, alkaline earth metal and ammonium salts and said mixture of sulfonated aryl-substituted alkanes being present in an amount sufficient to effect a substantial dispersion of soap curd in aqueous solution.

The references are:

Flett

Hoyt

Baumgartner

Hewitt

2,390,295

2,438,169

2,723,240

2,972,583

Dec. 4, 1945

Mar. 23, 1948

Nov. 8, 1955

Feb. 21, 1961

Flett discloses compositions “materially superior to an ordinary soap for cleansing in hard water” which contain water-soluble soaps and mixtures of al-kyl aromatic sulfonates, the latter having:

* * * the advantageous properties of preventing “lime soap” curds and related insoluble fatty acids and salts from depositing from aqueous suspensions thereof, while being themselves effective detergents and washing agents in hard water, sea-water and acid aqueous solutions. * * *

The alkylbenzenesulfonates of Flett, or what he terms a “keryl benzene sulfonate,” are prepared by chlorinating certain kerosene fractions of petroleum distillates — straight and/or branched chain alkanes containing 12 to 16 carbon atoms, “a large portion of which are probably relatively long carbon chains rather than more condensed molecules” — to form mixed alkyl chlorides; condensing the alkyl chloride mixture with benzene; and sulfonating. For water of somewhat limited hardness, Flett employs 5-10 parts of the alkylbenzene-sulfonate per 100 parts of soap, although “(f)or general use, compositions are preferred containing from 25 to 54 parts” per 100 parts of soap. In an example, a soap composition in bar form was prepared “without difficulty” by “milling, plodding and pressing” a mixture consisting essentially of 80 parts sulfonate and 160 parts soap stock. The resultant bars “lathered and washed excellently” in water of “extreme hardness.” When the relative amounts of the components were varied so that more than 66 parts of sulfonate were employed per 100 parts soap stock, it was noted that the compositions were “difficult to handle in the usual soap-working equipment because of stickiness.”

Hoyt discloses bar soap compositions containing a water-soluble soap, an al-kylbenzenesulfonate detergent (which he terms “petryl sulfonate”), and starch. In contrast to Flett, Hoyt observes:

* * * Preparation of a milled soap product by mixing a hard soap in a form usually employed for milling (e. g. in a form of ribbons, beads, particles, flakes, grains, or the like, containing 5% to 15% of moisture) with a higher petryl sulfonate in a substantial amount (e. g. 15% of the weight of the soap) presents difficulties; the mixture becomes sticky and tough so that it opposes milling and plodding in the usual commercial soap-making equipment. * * *

The addition of starch, says Hoyt, overcomes “the stickiness and toughness of the composition” and allows the mixtures to flow readily through the plodder or extruder.

Baumgartner discloses that two specific alkyl aryl sulfonates, which are within the class employed by appellants, exhibit “unusually high detergency at low concentrations in hard water.”

Hewitt discloses that, notwithstanding the fact that synthetic detergents often wash and foam better than fatty acid soaps and are not precipitated by alkaline earth ions in the wash water, soaps still account for a great amount of the toilet bar detergent sold. One reason given is that soaps are easy to process into bars, whereas such synthetic detergents as alkylbenzenesulfonates, whose alkyl groups are highly branched polyalkylene, are “not desirable constituents of detergent bars,” since they tend to be “tough and rubbery” and “resist normal processing more than solid detergents characterized by a crystalline structure.” The “keryl 2 benzene sulfonates are not as resistant to milling and plodding as the polyalkylene derivatives mentioned but they too are difficult to process.” Hewitt discovered that a detergent bar containing the compounds:

where IF is methyl and R is a mixture of straight chain alkyl radicals 6 to 16 carbon atoms in length, “possesses the detergency attributable” to the alkylben-zenesulfonates “but can be milled and plodded almost as easily as a soap bar.” Such a bar “foams well, has excellent de-tersive properties and is hard but soap-like to the touch.” Hewitt also adds a plasticizer to his composition which possesses “both hydrophilic and lipophilic groups,” such as saturated fatty acids. Such a plasticizer acts to cohere the synthetic detergent particles in the bar and to stabilize the detergent foam in use.

The board affirmed the examiner’s rejection of all claims as unpatentable over Flett and Hoyt in view of Baum-gartner and Hewitt under 35 U.S.C. § 103. Both felt that it would be obvious to one of ordinary skill to substitute the specifically disclosed detergents of Baumgartner and Hewitt for those of Flett and Hoyt, particularly in view of the known advantages disclosed by the secondary references for those particular alkylbenzenesulfonate detergents.

Appellants’ arguments are, in the main, two-fold. They first contend that neither Baumgartner nor Hewitt suggests that the particular alkylbenzene-sulfonates employed by appellants and disclosed by those references would be an effective lime-soap dispersant. The mere fact that those sulfonates are said to be superior detergents, appellants state, does not mean they necessarily would be considered suitable lime-soap dispersants. Nor, they say, does Flett teach that any and all detergents are useful lime-soap dispersants, but teaches only that the class of alkylbenzene-sulfonates disclosed by him are so useful. Secondly, appellants contend that none of the references suggests that the “stickiness” problem encountered by the prior art with the use of certain alkyl-benzenesulfonates in the manufacture of soap bars could be overcome, without the use of starch, by utilizing the instant class of alkylbenzenesulfonates.

Insofar as appellants’ first point is concerned, they have argued as if the elass of sulfonates they employ is a class entirely distinct from those employed by Flett. They seem to equate Flett’s “ker-yl” sulfonates only with the straight chain normal alkylbenzenesulfonates described as known detergents and lime-soap dispersants in their specification. That does not appear to be entirely the case. 3 It is apparent that Flett discloses among other things the use of straight chain “keryl” benzene sulfonates which, following the definition of Hewitt, include relatively large amounts of compounds having a straight chain hydrocarbon containing 12-16 carbon atoms medially or more centrally attached to the benzene radical. Those materials do not appear to differ substantially from appellants’ and are included within those disclosed by Flett to be lime-soap disper-sants at concentration levels comparable to those employed by appellants. We cannot agree that one of ordinary skill in the art would be unaware that the rather large class of alkylbenzene-sulfonates recited in appellants’ claims would possess lime-soap dispersant properties. The fact that Hewitt discloses that the instant alkylbenzenesulfonates possess good foaming properties would, following the criterion established in appellants’ specification, provide some further suggestion of the lime-soap dispersing properties of those materials.

With regard to appellants’ second point, there does appear to be some unresolved inconsistency between the earlier disclosure of Flett that “stickiness” is no problem at “keryl” benzene sulfonate concentrations less than 66% of the weight of fatty acid soap in the bar and the later disclosure of Hoyt that “stickiness” becomes a problem at “keryl” benzene sulfonate concentrations greater than 15% of the weight of soap, thus necessitating the use of starch.

Granted the problem exists, it seems to have been quite universal, whether attempts were made to employ the highly branched or keryl benzene sulfonates of the prior art in compositions with water-soluble soaps (Hoyt), or in compositions without them (as reported by Hewitt). It appears to us, as it did to the examiner, that Hewitt’s discovery that certain alkylbenzenesulfonates, corresponding in large measure to those appearing in appellants’ claims, would solve certain “milling” and “plodding” difficulties if employed in synthetic detergent bars would suggest to one of ordinary skill that a similar problem in Flett’s or Hoyt’s compositions might be solved if those compounds were employed in the course of manufacturing bars containing both fatty acid soaps and alkylbenzenesulfonates.. Appellants provide no answer to the examiner’s line of reasoning in arguing that the technology of making bars from synthetic detergent is somehow “quite distinct” from the technology of making bars based largely on soap. Nor does the examiner’s reasoning appear to involve any elements of “obvious to try” as asserted by appellants. Cf. In re Huellmantel, 324 F.2d 998, 51 CCPA 845 (1963); In re Pantzer, 341 F.2d 121, 52 CCPA 1135 (1965).

Both appellants and the solicitor rely on this court’s decision in In re Wilson, 4 368 F.2d 269, 54 CCPA 934 (1966), as controlling of the respective positions espoused by them. It should not be necessary to reiterate that each case is decided on its own facts. Suffice to say that we find the evidence of record here sufficient to provide reason for doing what appellants have done and to support the conclusion below that the claimed compositions would have been obvious to one of ordinary skill in the art at the time the invention was made.

The decision is affirmed.

Affirmed.

SMITH, Judge, concurs in the result.

1 . Appearing in application Serial No. 103,737, filed April 18, 1961, and entitled “Soap Compositions.”

2 . Hewitt states:

The word “keryl” identifies the type of mixture of alkyl groups obtained in an alkyl aryl sulfonate made by chlorination of kerosene followed by reaction with benzene (usually in presence of aluminum chloride) and sulfonation. Keryl radicals contain relatively large amounts of straight chain hydrocarbon medially joined to the aryl radical. [Emphasis supplied.]

3 . Neither appellants nor the examiner has pointed out in any detail just how the mixture of alkylbenzenesulfonates appellants employ and define in their claims differs from the “keryl” benzene sul-fonate mixtures disclosed by Flett and further defined by Hewitt. One difference may be that appellants’ mixture includes no compound in which the end or terminal carbon of the straight alkyl chain is attached to the benzene ring while seemingly Flett’s mixture (and the-“keryl” sulfonates described by Hewitt) would contain some amount of such material due to the random substitution of chlorine in the kerosene molecules during the initial chlorination reaction step. Another difference may be that appellants’ mixture includes little, if any, branched alkyl substituents while the “keryl” mixtures of the reference do because of the nature of the kerosene starting material, although that difference is tempered by the disclosure in appellants’ specification regarding their alplia-olefin starting materials :

It is also recognized that petroleum-derived alpha olefins may contain small amounts, i. e., 10-15% of impurities such as alpha olefins having some degree of branching and/or olefins having an internal double bond and/or olefins having more than one double bond. [Emphasis supplied.]

4 . There this court stated, in dealing with the same Flett patent as is involved here:

Although the board apparently believed the substitution of any known detergent for the alkyl aromatic sul-'fonate detergents in the Flett soap compositions would be obvious, we do not agree with this broad proposition, absent any given reason for making the substitution of detergents. [Emphasis supplied.]