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                         COMMISSIONER'S DECISION

 

   Anticipation; Claiming - Encapsulating Insecticidal Products

 

   Fungicides, pharmaceuticals and other chemical products are encapsulated with

   polyurea to provide ease of handling, slow release, delayed action and other

   advantages. The process claims had been considered allowable, but the

   product claims were refused for anticipation, and for being improperly

   dependent upon the process claims. It was concluded the products were

   physically different from the prior art, and that this was a proper

   case for making the product claims dependent upon the process claims.

 

   Rejection: Reversed

 

                              ************

 

   Patent application 164,086 (Class 117-47) was filed on February 20,

   1973, for an invention entitled "Encapsulation Process." The inventor

   is Herbert B. Scher, assignor to Stauffer Chemical Company. The

   Examiner in charge of the application took a Final Action on March 9,

   1978, refusing to allow it to proceed to patent. In reviewing the

   rejection, the Patent Appeal Board held a Hearing on October 24,

   1979, at which the Applicant was represented by Mr. W. Mace.

 

The invention claimed is one of encapsulating fungicides, pharmaceuticals,

   and other chemical products within a shell of polyurea. Among other

   advantages, the capsules permit slow release and delayed action of the

   material within the capsules. It permits easier handling of volatile

   insecticides.

 

   Of the 88 claims, sixty-four are directed to the process of encapsulation.

   No objections are now being made against the process claims, though we

   question the need of such a large number to protect what is a relatively

   straight-forward method. Conceivably Rule 44 might have been applied

   against some of them, and the Applicant might still wish to consider

   reducing their number.

 

What has been rejected are the claims to the product, 47-71, and we limit

our attention to them. They were refused on two grounds, firstly that they

are claimed by the process to make them, rather than by structure and

properties; and secondly on the ground that they are old, having been

disclosed in U.K. patent 1091141, Nov. 15, 1967, to Vandegaer, May 4, 1971,

mentioned on page 4 of the disclosure.

 

Typical claims in the application are 1, 5, 47 and 48, which are reproduced

below:

 

1. A process of encapsulating water-immiscible material within a

shell of polyurea which comprises the steps:

 

(a) providing in an aqueous phase a solution comprising water,

a surfactant and a protective colloid;

(b) adding to said aqueous phase a water-immiscible phase

comprising the water-immiscible material to be encapsulated

and an organic polyisocyanate;

(c) dispersing said water-immiscible phase in said aqueous

phase to establish droplets of the water-immiscible phase

in said aqueous phase;

(d) adjusting the pH of said aqueous phase to a value

between 0 and 14;

(e) heating and maintaining the dispersed water-immiscible phase

and aqueous phase in a temperature range of about 20øC. to

about 90øC.; whereupon said water-immiscible material is

encapsulated within a polyurea capsular enclosure.

 

5. The process of Claim 1 in which said water-immiscible material

is water-immiscible organic material.

 

47. Capsules capable of controlled release of encapsulated organic

material comprising a thiocarbamate herbicide enclosed in a skin of

a polyurea in the form of a microcapsule produced by the process of

Claim 5.

 

48. Capsules of Claim 47 in which said thiocarbamate herbicide is S-ethyl

diisobutylthiocarbamate.

 

From what was said at the Hearing it is clear that the products claims are

chemically the same as those disclosed in Vandegaer. Example 6 of Vandegaer,

in particular, shows the production of organic material encapsulated with in

a polyurea skin. At one stage Applicant contended the two products were

chemically distinguishable from each other (letter of July 19, 1977, p.1),

but has now retreated from that position. It is Applicant's present

contention, however, that despite their chemical similarity, there are

physical differences between the two, sufficient to patentably distinguish

one from the other. These physical differences are the result of Applicant's

new method of encapsulation. These physical differences were not fully explained

in the original disclosure when it was filed. They were first developed in

some detail in the response of July 19, 1977, at page 2, where it was

said Applicant's capsules have smooth walls rather than the sponge-like

form in Vandegaer, and that the smooth wall "provides certain advantageous

control release properties." It was also stated there were chemical

differences from the prior art capsules.

 

In a still later letter, that of June 7, 1978, Applicant has pointed out some

other physical differences. He mentions that his particles do not

agglomerate together but remain discrete; that the capsules dry to a powdery

solid rather than a rubbery clump; and that these properties provide

advantageous control release properties not inherent in the prior art capsules.

 

From those submissions we are satisfied that Applicant's products do differ

from those in the prior art, and that such differences are patentably

significant.

 

There is still a question whether Applicant disclosed that his products were in

any way different from that in the prior art when he filed his application,

so that it can be said he fully described the invention within the meaning

of Section 36(1) of the Patent Act. At the top of page 4 of the disclosure

he indicated that they had an "extremely thin skin." At the bottom of the

same page he referred to the provided "special advantages." On page 6

it is said the product of the new process "is particularly suitable for

direct agricultural pesticidal applications." On page 16 it is said that

capsules made by Applicant's process have "special utility" for encapsulation

by various volatile or unstable insecticides and herbicides. In example 5

it is shown that the product can be dried to produce "discrete spheroid

particles," one of the advantages stressed in Applicant's letter of

June 7, 1978 (supra). In example 1 he has shown they are "discrete capsules"

 which "disperse well."

 

That such differences do in fact exist was confirmed, and elaborated upon

in an affidavit of Herbert Benson Scher submitted after the final rejection

on Sept. 21, 1979. The photomicrographs attached to the affidavit clearly

show the physical differences.

 

The disclosure of the application is not nearly so complete, but we are of

the view that the portions referred to above are such that we cannot clearly

say the Applicant did not point to his particles being different from

Vandegaer's. Consequently we believe the objection based upon that citation

and upon inadequate disclosure should be withdrawn. It is unfortunate

that the material referred to in the preceding paragraph had not been

included in the original disclosure. In that event there would have been

no need for this review.

 

We turn now to the second main branch of the Examiner's rejection. Has the

Applicant properly claimed the products when he defines them by the process by

which they were manufactured? The Examiner has said that they should be

defined by their properties and structure. In his argument Applicant has

replied:

 

...

 

...Applicant respectfully submits that the specific structure

of the polyurea microcapsule of claims 47 to 71 is most

difficult to physically define other than to state that the

polyurea forms a skin for the encapsulated organic material.

Applicant in his response of July 19, 1977, suggested that

the capsule wall is a smooth membrane-like structure;

however as further indicated in the response submitted

December 5, 1977, applicant deemed it advisable to define

the walls as a skin in view that there was no support

for the term "membrane-like" in the present specification.

Applicant was thus able to define the structure of the wall

as being a "skin". It is thus readily seen that the product

is not sysceptible to structural definition.

 

...

 

He has also made extensive arguments based upon Section 8.04 of the Manual

of Patent Office Practice. However, since the Manual is only a guide to practice,

and not an authority to be used as justification for refusing or allowing

applications, we do not believe we should entertain arguments as to

whether the Manual has been complied with or what the Manual means. In-

stead we should direct our consideration to whether or not the claims

satisfy the strict requirement of Section 36 of the Patent Act that the

claims must be distinct and explicit.

 

Clearly the most explicit form of claim for claimed products is one which

defines the chemical structure or composition of that product. It is,

however, well recognized in patent law (one might refer to numerous patents

both in Canada and elsewhere) that when it is impossible to define a new

product by structure because that structure is not known and cannot be

readily ascertained, that the product may be defined by other means such

as properties or method of manufacture. This is permitted when it will

serve to distinguish an inventor's product from other products, whether those

other products already exist or not.

 

In the present use Applicant says the structure and composition are most

difficult to define other than by the manner of producing the product.

He has said that the chemical and physical properties vary depending upon

the reactants employed, and the physical properties would be most difficult

to define. We note, too, that in some ways it is similar to the products

made by Vandegaer, so that there are added difficulties in distinguishing

Applicant's products from Vandegaer's. This is, in our view, consequently

a case where the only way to define the product is by the way of

manufacturing it, and we recommend that that style of claim be accepted

in this case.

 

G.A. Asher

Chairman

Patent Appeal Board, Canada

 

I have considered the prosecution of this application and the recommendation

of the Patent Appeal Board. I have decided that the objections made

should be withdrawn, and remand the application to the Examiner for action

consistent with my decision.

 

J.H..A. Gariepy

Commissioner of Patents

 

Dated at Hull, Quebec

this 9th. day of June, 1980

 

Agent for Applicant

 

Gowling & Henderson

Box 466, Terminal A

Ottawa, Ont.

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