PCT (Patent Co-operation Treaty)
The Patent Cooperation Treaty (PCT) assists applicants in seeking patent protection internationally for their inventions, helps patent Offices with their patent granting decisions, and facilitates public access to a wealth of technical information relating to those inventions. By filing one international patent application under the PCT, applicants can simultaneously seek protection for an invention in 148 countries throughout the world.
PCT application is also known as the international phase of a patent application. It facilitates the prosecution of the subsequent national phase stage in other countries by virtue of the procedures carried out on the international application. The formalities check, the international search and the optional supplementary international search(es) and international preliminary examination which are carried out in this PCT stage enables the applicant to have more time and a better idea of whether and in which countries to continue with the national phase of the application.
A PCT application can claim priority from one or more prior applications filed in the Contracting States. After grant, it will give the applicant about 30 months from the filing date of the earliest priority application or the PCT application to enter into the national phase stage in countries of the applicant’s choice.
You may find the official PCT Applicant's guide here, by WIPO: http://www.wipo.int/pct/en/appguide/index.jsp
Drafting patent application document (English)
Drafting patent application document (Chinese)
Filing PCT application
Filing fee (including the search fee and publication, filing via China Patent Office)
Extra fee for each page of the patent document exceeding the 30th