DWPI DWPI DERWENT WORLD PATENTS INDEX YEARS SOURCES MILLION RECORDS
1970 USPTO 80% ( 1) Derwent World Patents Index (DWPI SM ) 50 75,000 DWPI DWPI 1. Eighth Technology Assessment and Forecast Report. Section II: The uniqueness of patents as a technological resource, Part I. Patents as a technological resource, USPTO Office of Technology Assessment and Forecast, 1977. DWPI 2
(IPC) IPC DWPI 170 DWPI (PACO) Thomson Innovation DWPI DWPI SIEI-C Siemens AG SIEI-C Siemens AG Siemens Corp Siemens Ltd, Osram-Sylvania AG DWPI 3
DWPI DWPI 1883 12 ( ) DWPI DWPI DWPI DWPI DWPI 4
Derwent AN: 2008-A87044 DWPI Method of determining low molecular weight naphthenic acid involves applying separated naphthenic acid from hydrocarbon composition to macroreticular ionexchange resin having transition metal ion with amine/ammonia; and eluting ion complex GB2439387A 20071227 (200806)* EN EP1870706A1 20071226 (200806) EN US20070298505A1 20071227 (200806) EN GB 2006-12344 20060621 GB USEP GB DWPI 5
DWPI DWPI 2,300 DWPI DWPI150 2 NON-CONVENTIONAL 12 DWPI Non-Conventional DWPI DWPI 1,500 DWPI 6
DWPI400 DWPI DWPI DWPI 7
DWPI 20~30 DWPI DWPI DWPI 8
DWPI DWPI 2 DWPI DWPI DWPI DWPI 300 DWPI DWPI 9
10 DWPI DWPI 22,000 DWPI DWPI3 DWPI DWPI DWPI 2,300
DWPI DWPI DWPI 11
100 60,000 ip-science.thomsonreuters.jp/ips/ DERWENT WORLD PATENTS INDEX DWPI DWPI48 5,000 IP 107-61195 2 20 19 Tel:03-4589-3101 Fax:03-4589-3240 Email: ts.info.jp@thomsonreuters.com Web: ip-science.thomsonreuters.jp 1003278 Copyright 2013 Thomson Reuters