PTO Manual of Classification for US patents

PTO Manual of Classification for US patents

What follows are the subclasses from one class of the Manual of Classification for US patents. As you scroll through the list and encounter a class/subclass of interest, you can jump back to the top and retrieve patent titles by entering the class/subclass in the box below.


Enter a class/subclass code here to get a list of patent titles. Use any of the following forms:
363-131 121-55A 14-.5
that is, no embedded spaces, class and subclass seperated by a dash, and any subclass letters capitalized. Currently Design Patent titles (those in the classes of the form Dxx.yy) are not retreivable.

Enter class/subclass code:


Class Number: 503
 Class Title: RECORD RECEIVER HAVING PLURAL LEAVES OR A COLORLESS COLOR
              FORMER, METHOD OF USE, OR DEVELOPER THEREFOR

Subclass  Subclass
Number    Title

  200     HAVING A COLORLESS COLOR-FORMER, DEVELOPER THEREFOR, OR METHOD
           OF USE
  201     .Method of use, kit, or combined with marking instrument or
            organ
  202     .Color developed by mere decomposition of color-former
  203     .Duplicating master
  204     .Plural colors or plural diverse systems
  205     .Having a color desensitizer
  206     .Component noncoextensive with substrate
  207     .Having nonreactant particles of defined size
  208     .Having constituent defined in terms of melting temperature
  209     .Having nonchromogenic liquid spread-control or
            transfer-improving agent or component, color modifier,
            stabilizer or preservative
  210     .Heavy metal reactant
  211     ..Metal of atomic number 22-30
  212     ...Zinc
  213     .Identified solvent or dispersant for color-former, other than
            mere mineral oil
  214     .Identified reactant isolating material or capsule wall material
            or binder resin
  215     ..Synthetic resin capsule walls
  216     .Identified organic electron acceptor (developer) other than
            phenolic resin
  217     ..And identified color-former
  218     .Identified color-former
  219     ..And identified inorganic electron acceptor (developer), other
             than mere clay
  220     ..Furanone moiety-containing
  221     ...Fluoran or derivative
  222     ....Molecule having plural fluorans or more than three rings
               fused together
  223     ..Azole moiety-containing
  224     ..Polyphenylmethane moiety-containing
  225     .Identified electron acceptor (developer)
  226     .Spatial relationship specified between color-former and
            developer
  227     HAVING PLURAL INTERACTIVE LEAVES