Patent Yard Sign in
Expired European patentEurope

Novel ammonium salt useful as modifiers for rubber

EP 0308581 B1 · Applicant: SUMITOMO CHEMICAL COMPANY, LIMITED

EPO PDF

Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

Read the whole patent

Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Google PatentsEPO PDF

Why it's free to use

  • Filed May 11, 1988 and granted March 4, 1992. A European patent lasts at most 20 years from filing, so its term ended May 11, 2008.
  • A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by November 11, 2013.
  • We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledMay 11, 1988
PublishedMarch 29, 1989
GrantedMarch 4, 1992
Term endedMay 11, 2008
Application numberEP 88107631
Classification (CPC)C08K5/32

Timeline

Timeline From EPO dates

1989199119931995199719992001200320052007Application filedMay 11, 1988PublishedMarch 29, 1989Patent grantedMarch 4, 1992Term endedMay 11, 2008

Sources & verification

Official EPO records

Full published documentClaims, description and drawings as a PDF.EPOEuropean Patent RegisterProcedure, status, file inspection and legal events.EPOLinked open EP data recordThe bibliographic record this page is built from.EPO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comEspacenetNational family members and their legal status.European Patent Office

Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.