US4913865A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparing ultrafine particles of organic compounds
Assignee: RESEARCH DEVELOPMENT
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Filing: 1986-05-22
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Granted: 1990-04-03
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Expires: 2006-05-22
Abstract
Abstract A method for manufacturing ultrafine particles of hardly water-soluble or water-insoluble organic compounds is disclosed herein, and the method includes heating and evaporating the organic compound in a vacuum vessel in which an inert gas is introduced in a desired pressure, then condensing and depositing the vaporized organic compound on a recovering means cooled, the resulting ultrafine particles exhibiting a high negative zeta potential sufficient to form a stable water dispersion thereof.
Inventors
- 👤 Hideki Toyotama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:03
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/14; B; B01; B01D; B01D3/00; B01D3/34; B01D3/343; B01D7/00
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
77 words
A method for preparing ultrafine particles of an organic compound having a good affinity to a dispersion medium comprising the steps of: a. heating and evaporating the organic compound in a vacuum vessel while controlling the inert gas pressure in the vessel; b. condensing the resulting vapour and depositing on a recovering plate in the vessel; and wherein the inert gas is argon or nitrogen and the pressure thereof is controlled to be at highest 10 Torr.
Claim 2
Independent Claim
77 words
A method for preparing ultrafine particles of an organic compound having a good affinity to a dispersion medium comprising the steps of: a. heating and evaporating the organic compound in a vacuum vessel while controlling the inert gas pressure in the vessel; b. condensing the resulting vapour and depositing on a recovering plate in the vessel; and wherein the inert gas is argon or nitrogen and the pressure thereof is controlled to be at highest 10 Torr.
Claim 3
Dependent Claim
35 words
A method for preparing ultrafine particles of an organic compound according to claim 1 wherein the organic compound is a member selected from the group consisting of water-insoluble or hardly water-soluble medicines, vitamins and hormones.
Claim 4
Dependent Claim
63 words
A method for preparing ultrafine particles of an organic compound according to claim 1 wherein the organic compound is a member selected from the group consisting of α-bromoisovaleroylurea, barbital, phenobarbital, phenobarbital sodium, phenytoin, carbamazepine, haloperidol, diazepam, chlormezanone, phenacetin, acetaminophene, aspirin, ethenzamide, phenylbutazone, indomethacin, mepirizole, probenecid, lidocaine, epinephrine, cyproheptadine hydrochloride, digitoxin, sulfamonomethoxine, tolubutamide, chloramphenicol, ethyl p-hydroxybenzoate, vitamin B 13 , cortisone acetate and predonisone.
Claim 5
Dependent Claim
35 words
A method for preparing ultrafine particles of an organic compound according to claim 1 wherein the organic compound is a member selected from the group consisting of anthracene, pyrene, metal phthalocyanine, merocyanine, ferrocene and carbazole.
Claim 6
Dependent Claim
38 words
A method for preparing ultrafine particles of an organic compound according to claim 1 wherein the organic compound is a member selected from the group consisting of polyvinyl chloride, polyvinylalcohol, polyethylene, polystyrene, polyvinylpyrrolidone, polyvinylcarbazole, polyethyleneterephthalate, polyvinylidenechloride and polymethylmethacrylate.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-04-02 | 1993-10-02 | 1994-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-02 | 1997-10-02 | 1998-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-02 | 2001-10-02 | 2002-04-03 | $7700.00 | Window Closed / Lapsed |