← Back to Patent Explorer
US4069291A Expired / Lapsed US ⏱️ 0.0 years remaining

Densification of particulate porous fluorinated resins

Assignee: Kureha Corp
•
Filing: 1976-06-18
•
Granted: 1978-01-17
•
Expires: 1996-06-18
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A suspension of a particulate porous fluorinated resin in an aqueous medium containing a powder of an inorganic suspension stabilizer is heated approximately at a melting temperature of the resin whereby the resin is densified, the degree of densification of the resin depending on the heating temperature.

Inventors

  • 👤 Kunizoh Kidoh
  • 👤 Hideki Wakamori
  • 👤 Genzo Asai
  • 👤 Kazuo Kusida

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 20:51
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08J3/16; C08J2327/00; C08J2327/02; C08J2327/12; Y; Y10; Y10S; Y10S521/00; Y10S521/918

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 68 words
A process for increasing the bulk density of a porous particulate fluorinated resin, which comprises preparing a suspension of a particulate porous fluorinated resin in an aqueous medium containing, as a suspension stabilizer, a powder of an inorganic material which is insoluble or slightly soluble in water, and heating the suspension at approximately the melting temperature of the resin, thereby reducing the volume of the particulate fluorinated resin.
Claim 2
Dependent Claim 68 words
A process for increasing the bulk density of a porous particulate fluorinated resin, which comprises preparing a suspension of a particulate porous fluorinated resin in an aqueous medium containing, as a suspension stabilizer, a powder of an inorganic material which is insoluble or slightly soluble in water, and heating the suspension at approximately the melting temperature of the resin, thereby reducing the volume of the particulate fluorinated resin.
Claim 3
Dependent Claim 41 words
The process as set forth in claim 1, in which the fluorinated resin is selected from the group consisting of homopolymers and copolymers of a fluorinated ethylenically unsaturated monomer, the fluorinated ethylenically unsaturated monomer constituting a major portion of the copolymer.
Claim 4
Dependent Claim 28 words
The process as set forth in claim 2, in which the fluorinated ethylenically unsaturated monomer is selected from the group consisting of vinylidene fluoride, vinyl fluoride and chlorotrifluoroethylene.
Claim 5
Dependent Claim 41 words
The process as set forth in claim 1, in which the inorganic mateial is selected from the group consisting of ortho-, pyro- and tripoly-phosphates of Ca, Mg, Ba, Zn and Al, calcium carbonate, barium sulphate, titanium white and calcium hydroxy apatite.
Claim 6
Dependent Claim 38 words
The process as set forth in claim 1, in which the suspension is heated at a temperature ranging from the temperature at which endothermic fusion of the fluorinated resin occurs to the melting temperature of the fluorinated resin.
Claim 7
Dependent Claim 27 words
The process as set forth in claim 1, in which the bulk density of the particulate porous fluorinated resin to be processed is lower than 50 g/dl.
Claim 8
Dependent Claim 26 words
The process as set forth in claim 1, in which the suspension further contains a surface active agent to improve wettability of the particulate fluorinated resin.
Claim 9
Dependent Claim 34 words
The process as set forth in claim 1, in which the suspension further contains a member selected from the group consisting of a latent solvent for the resin and a plasticizer for the resin.

References Cited (Backward Citations)

US2609539A Cited
US3898311A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-01-16 1981-07-18 1982-01-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-01-16 1985-07-18 1986-01-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-01-16 1989-07-18 1990-01-17 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag