[tweetmeme source=”Intellogist” only_single=false]As a reference librarian I frequently get questions about patent search tools and their capabilities. A request I hear often is “how can I search patent data using a numeric property range?”
If you’re a chemist you have a nice option in Reaxys, or Reaxysfile on STN, but this file is strictly chemistry – it does not cover engineering and mechanical topics. And you may have heard of Knovel, a non-patent search product that allows property range searching in textbooks.
But where can one find a patent collection with searchable property ranges? This kind of search is possible in the full text PCT, Australian and Canadian collections on STN. Read more to find out about the PCTFULL, CAFULL and AUFULL files that have been produced by STN distributor FIZ Karlsruhe.
As background, the PCTFULL, CAFULL and AUFULL files were originally OCR collections produced by LexisNexis Univentio. FIZ Karlsruhe developed an in-house method to index the property data found in these patents. Indexing was performed over the entire English full text of the patent (title, abstract, description and claims), but note that only the English-language documents will have been indexed for property ranges; for the PCT collection, this omits a very significant portion of the database.
Date range coverage of these files is very good. The PCTFULL collection covers the full text of PCT publications back to the beginning of the collection in 1978, AUPATFULL covers Australian patent applications and patent specifications back to 1964, and CANPATFULL covers Canadian patent applications and patent specifications back to 1920. The reason for the specific coverage of the Australian and Canadian authorities is that FIZ Karlsruhe had the recent opportunity to index and re-load these files, and so decided to treat them with the same process.
By necessity, the indexing process includes automatic unit conversion: all indexed data has been converted into SI base units. For example, the system will index “6 hours” into 2.16×104 sec. User keyword queries will also be converted to SI base units when the search is executed, so that both query and text are normalized. For example, a temperature search in Celsius units will retrieve hits with ranges originally listed in Fahrenheit and Kelvin. Additionally, property searches can be combined with other search terms, and the full range of operators available on STN are available.
Both open range and exact value searches are allowed in the files. However, open range searches (e.g. any record with the property size > 100nm) may exceed system limits if the query is too broad, so restricting range searches is advised.
Exact value searching supports the use of tolerances (e.g. 100 ± 1 °C returns hits from 99 to 101 degrees Celsius). The FIZ Karlsruhe support material for range searching demonstrates that using at least small tolerances is a good idea – otherwise relevant references could be omitted. For example, an exact search on 100°C might miss a hit specifying 373K, which equals 99.85°C.
The searchable fields in these three files include over 30 physical and chemical properties. Just to give you an idea of the depth of the indexing, fields include:
- Amount of Substance
- Bit Rate
- Byte Rate
- Molar Concentration
- Viscosity (dynamic)
- Viscosity (kinematic)
- Luminous Emittance/Illuminance
- Luminous Flux
- Luminous Intensity
- Mass Flow
- Magnetic Field Strength
- Molar Mass
- Percent (Proportionality)
- Electrical Impedance/Resistance
- Area/Surface Area
- Spring Constant
- Surface Tension
- Velocity, Angular
A complete guide to these properties can be found in the Database Summary sheets for the AUPATFULL, CANPATFULL, and PCTFULL files on STN – use the PDF bookmarks to get to the “Search and Display Field Codes” section. And if you’re an STN user, you’ll understand me when I say that you can use EXPAND/PHP to see the list of searchable fields.
The only major downside to these files is that you must search them on STN – and yes, with apologies to FIZ Karlsruhe, this *is* a downside for those who aren’t comfortable with the STN search environment. However, to those who use STN, the flexibility of the command line environment is an advantage.
How do you handle numeric property range searches? Do you see yourself using these files in the future? Let us know in the comments!
This post was contributed by Landon IP Librarian Kristin Whitman. The Intellogist blog is provided for free by Intellogist’s parent company, Landon IP, a major provider of patent search, technical translation, and information services.