Growth of Patent Family for DD, Rigaku Unique Technology

Rigaku Corporation’s Direct Derivation (DD) Method is a general-purpose quantification method that uses the X-ray diffraction method. It is a revolutionary technology that can calculate weight ratio based solely on chemical composition data for each crystalline phase. The DD Method can be applied without restrictions regardless of the states of the substances that are mixed in a sample, ranging from high to low crystallinity and including amorphous substances¹,². 

Rigaku holds six basic patents on this unique technology, as well as 14 patents for improvements and related technologies, having registered them in Japan, the United States, various European countries, China, and Australia. A further 17 patents are pending worldwide. 

Rigaku is confident that the correct application of these patented technologies will enable the DD method, a revolutionary quantification method technology, to be of great service to customers. 

If you have any questions, concerns, or inquiries, contact us through the contact information provided below. 

Registered trademarks

  • Japan: DD Method, Direct Derivation Method
  • United Kingdom, China, South Korea: DD Method

Basic patents

JP6231726, US10962489, DE3425379, NL3425379, CN109073574, AU2016395998

Related patents

JP7015067, JP6930737, US11841334, US11402341, DE3667304, NL3667304, CN111033246, AU2018315828


Toshihiro Ishizuka, X-ray Laboratory, Rigaku Corporation
Tel: +81 8043897604

Note 1:
  • Toraya, H. (2016) J.Appl.Cryst.49, 1508–1516
  • Toraya, H. (2017) J.Appl.Cryst.50, 820–829
  • Toraya, H. (2018) J.Appl.Cryst.51, 446–455
  • Toraya, H. (2019) J.Appl.Cryst.52, 520–531
  • Toraya, H. (2019) Rigaku Journal35, No. 2, 27-34
  • Toraya, H. and Omote, K.(2019) J. Appl. Cryst.52, 13–22
  • Toraya, H. (2020) J.Appl.Cryst.53, 1225–1235
  • Toraya, H. (2021) Powder Diffraction36 (3),159-168
  • Toraya, H. (2022) J.Appl.Cryst.55, 439–441
Note 2:
  • Crystal Structure Analysis Of Powder Sample Of Pharmaceutical Cocrystals By The Rietveld Method And Quantitative Analysis Of Impurities
  • Quantitative Analysis Of Crystal Polymorphs By The DD Method
  • Quantitative Analysis Of Glass With The DD Method

Application notes can be viewed at the Rigaku Corporation Global Website