US4223070A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Impregnated porous granules with slow release pore membranes and process therefor
Assignee: Zeneca Inc
•
Filing: 1978-05-04
•
Granted: 1980-09-16
•
Expires: 1998-05-04
Abstract
Abstract Open-ended pores of a porous granule are filled with a liquid material which is at least partially immiscible with water, and sealed with a porous polyurea membrane which limits the release rate of the material into the surrounding medium. The membrane is formed by (a) applying to the bare granule an organic solution comprising the liquid material and an organic polyisocyanate, followed by (b) applying to the granule an aqueous solution comprising water and a catalytic amount of a catalyst selected from the group consisting of a basic organic tertiary amine and an alkyl tin carboxylate.
Inventors
- 👤 Alice U. Hahn
- 👤 Richard H. Rider
- 👤 Herbert B. Scher
- 👤 Garrard L. Hargrove
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:42
CPC Classifications
B; B01; B01J; B01J2/00; B01J2/006; A; A01; A01N; A01N25/00; A01N25/26; C; C05; C05G; C05G3/00; C05G3/40; C05G3/44; Y; Y10; Y10S; Y10S428/00; Y10S428/905; Y10S428/907; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991; Y10T428/2998
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
103 words
A method for impregnating a porous granule with a material which is at least partially immiscible with water and sealing said material within the pores of said granule by covering the openings of said pores with a porous membrane to effect a slow rate of release of said material from said granule, which comprises (a) applying to said granule an organic solution comprising said material and an organic polyisocyanate, and (b) applying to said granule an aqueous solution comprising water and a catalytic amount of a catalyst selected from the group consisting of a basic organic tertiary amine and an alkyl tin carboxylate.
Claim 2
Independent Claim
103 words
A method for impregnating a porous granule with a material which is at least partially immiscible with water and sealing said material within the pores of said granule by covering the openings of said pores with a porous membrane to effect a slow rate of release of said material from said granule, which comprises (a) applying to said granule an organic solution comprising said material and an organic polyisocyanate, and (b) applying to said granule an aqueous solution comprising water and a catalytic amount of a catalyst selected from the group consisting of a basic organic tertiary amine and an alkyl tin carboxylate.
Claim 3
Dependent Claim
15 words
A method according to claim 1 in which said organic polyisocyanate is an aromatic polyisocyanate.
Claim 4
Dependent Claim
15 words
A method according to claim 1 in which said organic polyisocyanate is a polymethylene polyphenylisocyanate.
Claim 5
Dependent Claim
29 words
A method according to claim 1 in which the concentration of organic polyisocyanate in said organic solution is within the range of about 2% to about 75% by weight.
Claim 6
Dependent Claim
30 words
A method according to claim 1 in which the concentration of said organic polyisocyanate in said organic solution is within the range of about 5% to about 50% by weight.
Claim 7
Dependent Claim
29 words
A method according to claim 1 in which the concentration of said catalyst in said aqueous solution is within the range of about 0.01% to about 10% by weight.
Claim 8
Dependent Claim
29 words
A method according to claim 1 in which the concentration of said catalyst in said aqueous solution is within the range of about 0.05% to about 5% by weight.
Claim 9
Dependent Claim
29 words
A method according to claim 1 in which said organic and aqueous solutions are applied at a temperature within the range of about 15° C. to about 30° C.
Claim 10
Dependent Claim
17 words
A method according to claim 1 in which said material sealed within said pores is S-ethyl hexahydro-1H-azepine-1-carbothioate.
Claim 11
Dependent Claim
18 words
A method according to claim 1 in which said material sealed within said pores is S-ethyl diisobutyl thiocarbamate.
Claim 12
Dependent Claim
17 words
A method according to claim 1 in which said material sealed within said pores is S-propyl dipropylthiocarbamate.
Claim 13
Dependent Claim
17 words
A method according to claim 1 in which said material sealed within said pores is S-ethyl dipropylthiocarbamate.
Claim 14
Dependent Claim
18 words
A method according to claim 1 in which said material sealed within said pores is O-ethyl S-phenyl ethylphosphonodithioate.
Claim 15
Dependent Claim
17 words
A method according to claim 1 in which said material sealed within said pores is S-ethyl cyclohexylethylthiocarbamate.
Claim 16
Dependent Claim
83 words
An article of manufacture which comprises a porous granule impregnated with a material which is at least partially immiscible with water, the pores of which are sealed with a porous polyurea membrane formed by (a) applying to said granule an organic solution comprising said material and an organic polyisocyanate, and (b) applying to said granule an aqueous solution comprising water and a catalytic amount of a catalyst selected from the group consisting of a basic organic tertiary amine and an alkyl tin carboxylate.
Claim 17
Dependent Claim
83 words
An article of manufacture which comprises a porous granule impregnated with a material which is at least partially immiscible with water, the pores of which are sealed with a porous polyurea membrane formed by (a) applying to said granule an organic solution comprising said material and an organic polyisocyanate, and (b) applying to said granule an aqueous solution comprising water and a catalytic amount of a catalyst selected from the group consisting of a basic organic tertiary amine and an alkyl tin carboxylate.
Claim 18
Dependent Claim
17 words
An article of manufacture according to claim 15 in which said organic polyisocyanate is an aromatic polyisocyanate.
Claim 19
Dependent Claim
17 words
An article of manufacture according to claim 15 in which said organic polyisocyanate is a polymethylene polyphenylisocyanate.
Claim 20
Dependent Claim
32 words
An article of manufacture according to claim 15 in which the concentration of said organic polyisocyanate in said organic solution is within the range of about 2% to about 75% by weight.
Claim 21
Dependent Claim
32 words
An article of manufacture according to claim 15 in which the concentration of said organic polyisocyanate in said organic solution is within the range of about 5% to about 50% by weight.
Claim 22
Dependent Claim
31 words
An article of manufacture according to claim 15 in which the concentration of said catalyst in said aqueous solution is within the range of about 0.01% to about 10% by weight.
Claim 23
Dependent Claim
31 words
An article of manufacture according to claim 15 in which the concentration of said catalyst in said aqueous solution is within the range of about 0.05% to about 5% by weight.
Claim 24
Dependent Claim
31 words
An article of manufacture according to claim 15 in which said organic and aqueous solutions are applied at a temperature within the range of about 15° C. to about 30° C.
Claim 25
Dependent Claim
19 words
An article of manufacture according to claim 15 in which said material sealed within said pores is S-ethyl hexahydro-1H-azepine-1-carbothioate.
Claim 26
Dependent Claim
19 words
An article of manufacture according to claim 15 in which said material sealed within said pores is S-ethyl diisobutylthiocarbamate.
Claim 27
Dependent Claim
19 words
An article of manufacture according to claim 15 in which said material sealed within said pores is S-propyl dipropylthiocarbamate.
Claim 28
Dependent Claim
19 words
An article of manufacture according to claim 15 in which said material sealed within said pores is S-ethyl dipropylthiocarbamate.
Claim 29
Dependent Claim
20 words
An article of manufacture according to claim 15 in which said material sealed within said pores is O-ethyl S-phenyl ethylphosphonodithioate.
Claim 30
Dependent Claim
19 words
An article of manufacture according to claim 15 in which said material sealed within said pores is S-ethyl cyclohexylethylthiocarbamate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-16 | 1984-03-17 | 1984-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-16 | 1988-03-17 | 1988-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-16 | 1992-03-17 | 1992-09-16 | $7700.00 | Window Closed / Lapsed |