Application of John Hampton Moore

The issue here is whether the Board of Appeals committed reversible error in affirming the examiner’s rejection of claims 3-101 in view of certain prior art under 35 U.S.C. § 103.

The invention relates to a pre-measured, dry bleach packet for use in home laundry. By way of background, the specification states:

It is well known that pre-weighed amounts of detergent products and bleach products can be packaged in water soluble films as, for example, polyvinyl alcohol to provide convenience in handling and measuring and freedom from dust. However, when chlorine bleach compounds are packaged in polyvinyl alcohol film, the reactivity of said chlorine compounds and other materials associated with said chlorine compounds is such that the polyvinyl alcohol film tends to be made insoluble in water. Since the utility of this form of packaging depends upon the water solubility or dispersibility of the polyvinyl alcohol film, such insolubilization makes it difficult to prepare acceptable chlorine bleach packets. [Emphasis supplied.]

To obviate those problems associated with polyvinyl alcohol (PVA) envelopes containing a chlorine bleach, appellant has devised a product consisting of (1) an outer envelope of water-soluble PVA containing a relatively small percentage of unhydrolyzed polyvinyl acetate and plasticized with various “external” plasticizers, and enclosed therein (2) a dry, water-soluble bleach product consisting essentially of a particular chlorine bleach —potassium dichlorocyanurate2 (hereafter KDCC) — and such optional ingredients as alkaline salts, inert bulking salts and synthetic detergents, as reflected in claim 3:

3. A bleaching packet consisting essentially of (a) an envelope of polyvinyl alcohol film containing from about 5% to about 40% unhydrolyzed vinyl acetate, said film being plasticized with a plasticizer selected from the group consisting of glycerine, ethylene glycol, polypropylene oxides having a molecular weight of from about 150 to about 400, polyethylene oxides having a molecular weight of from about 100 to about 300, copolymers of propylene oxide and ethylene oxide having a molecular weight of from about 100 to 400, alkyl phenol ethylene oxide condensates having a molecular weight of from about 200 to about 1000 wherein the alkyl group has from about 1 to about 18 carbon atoms, phenol ethylene oxide condensates having a molecular weight of from about 200 to about 400, and mixtures thereof, (b) and enclosed therein a dry water-soluble bleach product consisting essentially of from about 5% to about 30% potassium diehloroeyanurate material having a pH ranging from about 5.8 to 6.4, the balance being 0% to 98 % alkaline material selected from the group consisting of trisodium phosphate, tripotassium phosphate, sodium tripolyphosphate, sodium carbonate, potassium carbonate, sodium silicate, potassium silicate, and tetra-sodium pyrophosphate, 0% to 98% inert material selected from the group consisting of sodium sulfate, sodium chloride, and potassium chloride, and 0% to 30% bleach compatible synthetic detergent surfactant selected from the group consisting of soap and anionic non-soap, and nonionic organic synthetic detergents, the pH of said composition being from about 9 to about 11, and the total moisture content of said composition being less than about 15 % and the free moisture content being less than about 1%.

It appears from the specification that appellant has taken various measures to stabilize his bleach product in order to minimize reaction between bleach product components (including KDCC, its degradation products, and the other additives) and water-soluble PVA. Thus, appellant uses at the outset a relatively pure KDCC material having a pH from about 5.8 to about 6.4,3 postulating that KDCC of lower purity and pH contains (1) certain inorganic acids, such as hypochlorous acid (HOC1), which cause the formation of insolubilizing ether cross-links between adjacent molecules of polyvinyl alcohol during storage of the bleach packet, and (2) certain other acidic impurities, such as trichloroeyanuric acid or diehlorocyanuric acid, “which are detrimental to product stability.” Appellant further employs a bleach composition which has a total moisture content, including water of hydration, of less than 15% and a free moisture content of less than 1%, having found that water reacts with KDCC or its impurities to produce the deleterious, PVA-insolubilizing, inorganic acids. Advantageously, the individual particles of KDCC may be “protectively” coated4 with a material which appears to form a barrier to moisture penetration. Finally, appellant states, acidic degradation products of KDCC, once formed, can be neutralized and prevented from reacting with the PVA film enclosure by including in the bleach composition sufficient alkaline material to give a total product pH of “preferably” about 9 to 11.

According to the specification, the final bleach product may be in granular form or “in the form of compressed tablets.” In the latter case, it is said the PVA film “helps to maintain the tablet form of the bleach product.”

The references are:

Abbott 2,635,400 April 21, 1953

Morgenthaler 3,112,274 Nov. 26, 1963

Lee 3,120,378 4, 1964 Feb.

Fuchs (Australia) 219,930 22, 1959 Jan.

Miller (Canada) 510,555 7, 1955 Mar.

Marks (German) 1,053,739 26, 1959 Mar.

‘Elvanol,” Publ. of E. I. DuPont & Co. (1947), pages 4,17,18,19, and 31.

Fuchs observed that various chlorine-containing bleaches, including trichlorocyanuric acid, had not been satisfactory for commercial use because of “lack of adequate stability during formulation into commercial preparations and during storage.” In contrast, he found dichlorocyanuric acid “to have excellent stability” during manufacture and storage. The alkali metal salts of diehlorocyanuric acid may also be used, being more soluble than the acid itself and forming “solutions that are approximately neutral.” For practical use, the bleach material may further be combined with various alkaline compounds, synthetic detergents and inorganic fillers. In that regard, Fuchs states:

The presence of alkaline compounds aids in the release of chlorine from diehlorocyanuric acid and therefore renders the latter compound more effective for bleaching and other applications in which an alkaline solution of a hypochlorite is needed. A very high alkalinity, such as indicated by a pH of 12 or higher, is in general undesirable and hence when free hydroxides, such as sodium hydroxide, are used, the amount must be carefully controlled.

Morgenthaler discloses a stable, dry-bleach composition comprising granules of a polychlorocyanurate (e. g., tri-and dichlorocyanurie acid and alkali metal salts of dichlorocyanurie acid) spray-coated with an inorganic salt, preferably alkaline,5 to protect the polychlorocyanurate from attack by material with Miich it is reactive, such as moisture and air “which are known to increase the tendency of such compounds to decompose.” Preferred polychlorocyanurates are the sodium and potassium dichlorocyanurates “since they are more stable than the polychloroeyanuric acids.” Sodium tripolyphosphate alone or in admixture with sodium sulfate (an inert salt) is the preferred alkali which provides “the desired buffered alkalinity for the optimum bleaching activity of the polychloroeyanurate.” The alkaline coating may also contain 0-10% suitable synthetic anionic detergents. The weight ratio of coating material to polychlorocyanurate ranges from 1:3 to 5:1. The coating material (a slurry) should have a pH less than 11 since “a pH higher than about 11 undesirably decreases the stability of the polychlorocyanurate particles on which it is sprayed.” Total moisture content is in the range of 2-15%. The free moisture content of the final product is a carefully controlled variable, Morgenthaler stating:

* * * The finished product should not contain more than about 2% free moisture, preferably not more than about 1%, since more than this amount decreases the stability of the product •* * *

Finally, Morgenthaler observes:

The coated polychlorocyanurate particles obtained in the process of this invention are more stable and have less chlorine odor than either uncoated polychlorocyanurate particles or granular products having the same composition but dried by different processes. Other drying processes do not provide the protective coating that is obtained in the process of the present invention. This coating comprises a substantially complete film of inorganic salt around the polychlorocyanurate particles. [Emphasis supplied.]

Lee discloses a water-soluble bleach tablet possessing “excellent stability during storage” containing (1) dichlorocyanuric acid or its alkali metal salts, particularly the sodium salt or potassium salt (the latter being KDCC), (2) an alkali metal carbonate, (3) a hydrate forming compound and (4) a solid acid. The acid and carbonate react upon dissolution in water to form effervescent carbon dioxide which facilitates solution in water. The preferred tablet contains “no free water,” thus preventing the premature release of available chlorine. Lee prefers the dichlorocyanurates “rather than the well known trichloroeyanurates because of the greater stability” of the dichloro compound. According to Lee:

* * * The tablet can also be coated with a water soluble film, such as a polyvinyl alcohol film, if desired.[Emphasis supplied.]

All claims were rejected under § 103 as unpatentable over Fuchs or Morgenthaler in view of Elvanol, Abbott, Lee, Miller and Marks.6 The examiner and board were of the view that Fuchs and Morgenthaler each establish that appellant’s bleach product is “substantially old,” and that placing that product within a water-soluble PVA film would be “clearly obvious” in view of the secondary references. No patentable significance was attached to the claim limitations relating to moisture content and the pH of either KDCC or the total product.

Here, appellant urges that the prior art does not adequately suggest either the combination of KDCC-containing bleach and PVA film or the conditions required to produce a stable, water-soluble product. Throughout his brief, appellant asserts that the art was aware that all chlorine bleaches were incompatible with PVA film, yet had suggested no solution to that problem. He contends the board erred in ignoring the problem associated with packaging chlorine bleaches in water-soluble films and in failing to accord significance to the particular moisture and pH conditions recited in the claims. He points to certain data in his specification which assertedly establishes that the operational pH and moisture content ranges in the claims are necessary and critical to obtention of a bleach product having a PVA film covering which is not insolubilized in storage.

As the solicitor points out, there is little of record to substantiate appellant’s claim of what the art knew concerning the asserted incompatibility between chlorine bleaches and PVA film, other than the paragraph of the specification we have heretofore reproduced.7 That factor may in part account for the unfortunate circumstance that the examiner and board did not discuss or controvert the existence of the unsolved problem which appellant says the art faced with respect to packaging chlorine bleaches in PVA films, even though it was argued below. Cf. Graham v. John Deere Co., 383 U.S. 1, 17, 86 S.Ct. 684, 15 L.Ed.2d 545. But granted the problem of stabilizing an active chlorine-containing bleach composition did exist, it seems to have been quite universal, whether the ultimate product was to be packaged in foil-wrapped cardboard cartons, as suggested by Morgenthaler, or in water-soluble PVA envelopes as appellant intends here. While one of ordinary skill in the art might know that chlorine bleach materials other than a bleach containing KDCC were incompatible with PVA because of their reactivity and instability, no clear reason appears from the record why it would be thought KD CC would necessarily fall in the same category when stabilized and segregated in the manner taught by Morgenthaler. It seems to us that Morgenthaler’s discovery — that the spray coating of KDCC (which is desirably free of unstable tri- or dicloroeyanuric acids and instability-causing moisture) with an alkaline moisture barrier solved certain stabilization problems in his contemplated environment — would suggest to one of ordinary skill that a similar problem might be solved if Morgenthaler’s stabilized composition were to be used as the bleach component of a water-soluble bleach packet employing PVA as the packaging material. We see no reason why one of ordinary skill would necessarily be surprised that KDCC, when relieved of its free moisture and less- stable impurities and when “protectively” coated with alkali — indeed, effectively isolated from materials with which it might be reactive —in the manner taught by Morgenthaler, could be placed in a PVA envelope without the degree of danger of insolubilizing the film that previously existed.

With respect to the particular claim limitations relating to moisture content and pH that appellant relies on here, it appears that the prior art and appellant have proceeded in much the same manner to achieve the object of a stabilized product. Morgenthaler (and Lee, for that matter) desires a product of low free moisture content for the same reason as appellant — namely, to avoid premature release of available chlorine in the bleach in the form of acidic degradation products. Further, both appellant and the prior art recognize that the alkali metal salts of dichlorocyanuric acid offer the best stability of the various active-chlorine containing cyanurate bleaches, and that the presence of those other cyanurates, e. g., tri- or dichlorocyanuric acid, is not compatible with product stability. It seems clear that the prior art prefers to use a relatively pure KDCC — sans the tri- and dichlorocyanuric acids which arise as impurities in the course of manufacture of KDCC — for optimum stability, and that is about all that the claim recitation of a KDCC material pH range of 5.8-6.4 8 reflects.

Insofar as the pH value of the entire bleach composition is concerned, it is evident that Morgenthaler and Fuchs much prefer a composition having a pH in solution of between 7 and 11 or 12. The fact that those references do not precisely disclose the bleach product pH limitations of 9-11 recited in appellant’s claim is, we think, not of controlling significance here. Apart from the fact that appellant is operating within the alkaline range broadly suggested by them, there is no evidence in the record that operation within the claim limits is necessary or critical when employing Morgenthaler’s alkali-coated KDCC particles, rather than gross mechanical mixtures of KDCC and alkali particles, in the claimed combination as appellant concededly intends to do.

Our review of the record with due regard for appellant’s arguments convinces us the board did not err in sustaining the rejection. The decision is affirmed.

Affirmed.