Patent US5537180A successfully refreshed from Google Patents.
Patent US2288303A successfully refreshed from Google Patents.
Patent US5188782A successfully refreshed from Google Patents.
US5188782A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of preforms from ceramic or metallic fibers
Assignee: BASF SE
•
Filing: 1990-10-03
•
Granted: 1993-02-23
•
Expires: 2010-10-03
Abstract
Abstract Preforms are produced from ceramic and/or metallic fibers by injection molding or extruding a mixture containing the fibers and a thermoplastic binder, said thermoplastic binder being polyoxymethylene, which after the shaping is removed by treatment in a gaseous acid-containing atmosphere or in a gaseous BF 3 -containing atmosphere.
Inventors
- 👤 Knut Bittler
- 👤 Johan H. H. Ter Maat
- 👤 Hans-Josef Sterzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:02
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/22; B22F3/225; B22F1/00; B22F1/10; B22F3/002; B22F3/10; B22F3/1017; B22F3/1021; B22F3/1025; C; C04; C04B; C04B26/00; C04B26/02; C04B26/10; C04B30/00; C04B30/02; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/632; C04B35/634; C04B35/63448; C04B35/63488; C04B35/638; C04B35/71; C04B35/74; C04B35/76; C04B35/78; C04B35/80; C22; C22C; C22C47/00; C22C47/02; C22C47/06; C22C47/08; B22F2998/00; C04B2235/00; C04B2235/02; C04B2235/50; C04B2235/52; C04B2235/5208; C04B2235/5216; C04B2235/522; C04B2235/5224; C04B2235/5232; C04B2235/5236; C04B2235/524; C04B2235/5244; C04B2235/526; C04B2235/5264; C04B2235/60; C04B2235/602; C04B2235/6021; C04B2235/6022; C04B2235/70; C04B2235/94; C04B2235/95
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
59 words
A process for producing a preform from ceramic or metallic fibers by shaping a mixture containing the fibers and a thermoplastic binder by injection molding or extrusion and removing the binder, wherein the binder used is polyoxymethylene and it is removed after the shaping by treatment in a gaseous acid-containing atmosphere or in a gaseous BF 3 -containing atmosphere.
Claim 2
Dependent Claim
59 words
A process for producing a preform from ceramic or metallic fibers by shaping a mixture containing the fibers and a thermoplastic binder by injection molding or extrusion and removing the binder, wherein the binder used is polyoxymethylene and it is removed after the shaping by treatment in a gaseous acid-containing atmosphere or in a gaseous BF 3 -containing atmosphere.
Claim 3
Dependent Claim
19 words
A process as claimed in claim 1, wherein the mixture contains from 30 to 60% by volume of polyoxymethylene.
Claim 4
Dependent Claim
40 words
A process as claimed in claim 1, wherein fibers formed from Al 2 O 3 , ZrO 2 , SiO 2 , Y 2 O 3 , Si 3 N 4 , SiC, Si, Fe, B or Ti are used.
Claim 5
Dependent Claim
19 words
A process as claimed in claim 1, wherein the treatment is carried out at from 20° to 150° C.
Claim 6
Dependent Claim
28 words
A process as claimed in claim 1, wherein the acid used is nitric acid, a hydrohalic acid or an organic acid having a boiling point below 130° C.
Claim 7
Dependent Claim
20 words
A process as claimed in claim 4, wherein the treatment is carried out at from 70° C. to 150° C.
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) | 1996-02-23 | 1996-08-24 | 1997-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-02-23 | 2000-08-24 | 2001-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-02-23 | 2004-08-24 | 2005-02-23 | $7700.00 | Window Closed / Lapsed |