Application of Widmer

• Decision Date: 16 December 1965
• Docket Number: Patent Appeal No. 7474.
• Citation: 353 F.2d 752,147 USPQ 518
• Parties: Application of Gustav WIDMER, Hans Batzer and Edwin Nikles.
• Court: U.S. Court of Customs and Patent Appeals (CCPA)

147 USPQ 518, 353 F.2d 752 (1965)

Application of Gustav WIDMER, Hans Batzer and Edwin Nikles.

Patent Appeal No. 7474.

United States Court of Customs and Patent Appeals.

December 16, 1965.

Harry Goldsmith, Bryant W. Brennan, Summit, N. J., Joseph G. Kolodny, Baltimore, Md. (A. Ponack, Washington, D. C., of counsel), for appellants.

Clarence W. Moore, Washington, D. C. (J. E. Armore, Washington, D. C., of counsel), for the Commissioner of Patents.

Before WORLEY, Chief Judge, and RICH, MARTIN, SMITH, and ALMOND, Judges.

MARTIN, Judge.

This is an appeal from an affirmance by the Board of Appeals of the rejection of claims 3, 4, and 7-9, which are all the claims remaining in appellants' application serial No. 11,964, filed March 1, 1960, for "New Epoxy Compounds."

The invention relates to epoxy esters of carbonic acid which may be termed di-(3,4-epoxyhexahydrobenzyl) carbonates equivalent name: di-, or bis-(3,4-epoxycyclohexylmethyl) carbonates.¹ Those epoxy carbonate esters are light-colored monomers that are liquid or fusible at room temperature and can be cured with the usual hardeners for such polyepoxy (polyepoxide) compounds. Mixtures containing epoxy compounds of the invention and a hardener can be used as textile assistants, laminating resins, paints, lacquers, dipping resins, casting resins, fillers, putties, and adhesives, and are especially valuable as insulating compounds for electrical purposes. With reference to the groups giving rise to the particular nomenclature used hereinafter, the claimed epoxy carbonate esters may be depicted thus:

Z=a hydrocarbon radical of a polyalcohol or a polyphenol.

In order to appreciate the differences between the compounds claimed and those of the prior art, a short discussion of a method of preparing a compound representative of those claimed will be helpful. The claimed epoxy carbonate esters may be prepared by starting with a ring unsaturated cyclic alcohol, e. g.:

to which a carbonate group is added (by reaction with phosgene, or a carbonic acid ester) to form the ester linkage by a known method. The ring double bonds are then epoxidized,

(with peracetic acid) to produce the claimed epoxy monomers.

As noted above in the diagram of the claimed compounds, there may be a single carbonate group linking two cyclohexylmethyl, hexahydrobenzyl, rings, or, optionally, there may be an additional ester link of the nature the Z-link, inserted between the rings. If in the reaction which adds the carbonate group to the ring unsaturated cyclic alcohol, 2 moles of the alcohol are used, a compound containing a single carbonate link is formed, as, for example, in claim 3:

3. The compound of the formula If only one mole of alcohol is used, the resulting compound is the corresponding chloroformate:

Then the Z-link is added by reaction of a proper amount of the chloroformate with polyhydroxy compounds, e. g., bisphenol A:

, producing, for example, the compound of claim 7:

7. The compound of the formula

Generic claim 9 covers both types and reads:

9. Epoxy compounds of the general formula

in which R1 and R5 taken together and R'1 and R'5 taken together each form a member selected from the class consisting of two hydrogen atoms, two lower alkyl radicals of 1 to 4 carbon atoms and one methylene radical, R2, R'2, R3, R'3, R4, R'4, R6, R'6, R7, R'7, R8, R'8, R9 and R'9 each represent a member selected from the class consisting of hydrogen atoms and lower alkyl radicals of 1 to 4 carbon atoms, Z is a hydrocarbon radical with 2+(n-1).(p-1) free valences and is of the group consisting of the hydrocarbon radical of a polyalcohol and the hydrocarbon radical of a polyphenol, n represents a whole number of at least 1 and at the most 2, and p represents a whole number of at least 1. Claims 4 and 8 differ from claims 3 and 7 respectively in that one hydrogen on the number 6 ring carbon is replaced by a methyl group.

The following references are relied on for the rejection of claims 3, 4 and 7-9 under 35 U.S.C. § 103:

                  Phillips et al. (I)        2,750,395    June 12, 1956
                  Mueller et al.             2,795,572    June 11, 1957
                  Newey                      2,848,426    Aug. 19, 1958
                  Phillips et al. (II)       2,917,491    Dec. 15, 1959
                

A second ground of rejection involves generic claim 9 which was rejected "as failing to properly define the invention" within the meaning of 35 U.S.C. § 112. We do not reach that issue.

The Mueller et al. patent (Mueller) is directed to epoxy esters of carbonic acid and their polymers, which are thus of the same class of compounds as those disclosed by appellants. As do appellants, Mueller discloses and claims epoxy carbonate esters having either one or two carbonate ester linkages between alcohol moieties. Mueller's epoxy esters are prepared in the same manner as appellants'. In the latter type, the two carbonate groups may be separated by a radical derived from di-nuclear dihydric phenols, e. g., bisphenol A, to give the following compound:

By comparison with appellants' claim 7 it will be noted that only the terminal epoxy-containing moieties, derived from the starting reactant alcohols, are different.

Regarding the alcohol moiety of the Mueller epoxides, Mueller teaches and claims epoxyalkanols, epoxyalkoxyalkanols, expoxycycloalkanols, and epoxyalkoxycycloalkanols. Within each of those classes of alcohols Mueller names preferred members. Pertinent here is the disclosure that:

Particularly preferred epoxy-substituted alcohols are the * * * epoxycycloalkanols * * * and particularly those containing not more than 12 carbon atoms, such as * * * 3,4-epoxycyclohexanol * * * and the like.

As epoxy carbonate esters produced therefrom,² Mueller specifically discloses:

The preferred epoxy esters of the invention are those derived from * * * (2) epoxy-substituted aliphatic and cycloaliphatic monohydric alcohols containing from 3 to 12 carbon atoms, such as for example, * * * di-(3,4-epoxycylohexyl) carbonate, * * *.

The structure of that compound is:

It can be seen by comparing that structure with the structure of the compound of appellants' claim 3, that the carbonate group indirectly links the two rings through methylene bridges in appellants' compound, while in Mueller's compound the carbonate group is directly bonded to the rings.

The remaining references were cited to show the specific alcohol reactants used by appellants which would, when used in Mueller, result in epoxy carbonate esters having a methylene bridge, and, as called for in claims 4 and 8 and covered in generic claim 9, a methyl or other aliphatic group on the number 6 carbon of the cyclohexyl ring. All three secondary references are concerned with epoxy monomers (also termed epoxides) useful, as Phillips et al. (I) states, "in certain commercial applications such as, for example, surface coatings, laminates and plastic molding compositions." Newey states that his epoxides may be cured with what are apparently well-known curing agents, and that when the epoxides

* * * are to be used in the preparation of castings or pottings the curing agent and the epoxy material are generally combined together and then poured into the mold or casting which may if desired contain additional material, such as electrical wires, apparatus, etc., and the mixture then heated to effect the cure.

Newey also discloses his epoxy compounds to be useful in adhesive and impregnating compositions, and that when amines are reacted with the epoxides "high molecular weight products instead of cross-linked cured products," useful in making coating compositions, will be produced.

Exemplary alcohol reactants listed in Newey "include, among others, (3,4-epoxycylohexyl) methanol * * * and 3,4-epoxycyclohexanol * * *." It will be recognized that those two alcohols are the epoxidized forms of appellants' and Mueller's unsaturated alcohols; Newey also discloses that the corresponding unsaturated alcohol is used as the starting material, to be subsequently epoxidized with the same reactant as used by appellants. The compound of Newey's Example III shows the use of the 3,4-epoxycyclohexyl methanol:

The major difference between Newey and Mueller is that, like appellants, Mueller is directed toward epoxy carbonate esters while Newey's epoxides are epoxy ethers, and thus do not contain the -O- linkage. Also, while both Phillips references are directed to epoxides they are esters of dicarboxylic acids rather than of carbonic acid; they contain an linkage, rather than a linkage between the epoxycyclohexylmethyl rings.

I The Prima Facie Case of Obviousness

We agree with the board that upon these references the examiner has made a prima facie showing that the claimed epoxy carbonate esters are obvious. The board stated:

We agree with the Examiner that the Phillips et al. and Newey patents make the substitution of a 3,4-epoxycyclohexyl-methyl alcoholic component for the 3,4-epoxycyclohexyl component of the Mueller et al. esters an obvious expedient. Mueller et al. describe the epoxy-substituted aliphatic and cycloaliphatic monohydric alcohols as being preferred epoxy-substituted alcohols in preparing their esters of carbonic acids * * *.

Newey\'s disclosure of the equivalent or alternative use of epoxycyclohexyl and epoxycyclohexyl-methyl radicals as the terminal reactive radicals in his disclosed polyepoxides would suggest the alternative use of these radicals, with or without the substituents that Phillips et al. show to be conventional, as the terminal radicals in the Mueller et al. compounds.

It is quite clear from the references that appellants' starting reactant alcohol is well-known in the art as a starting reactant to make other epoxy monomers useful for the same purposes as those disclosed by appellants. While the epoxides of Newey and the Phillips references are either ethers or carboxylic acid esters, rather than being carbonic acid esters as in Mueller and appellants' application, it is clear...