(under the class definition) Apparatus comprising means specifically designed or modified to cause or aid the generation or expansion of pores within the work during or prior to shaping.
(1) Note. To be included herein, the apparatus must include means to mechanically introduce a gas into the work, (e.g.., gas injection means, beaters, gaseous pressure or vacuum chambers, (etc..). Means causing of controlling a chemical reaction, (e.g.., heating means, cooling means, means mixing reactive ingredients, etc..), are classified in appropriate subclasses below even though the reaction results in a formed or porous article. Means injecting steam into an area confining partially expanded beads to cause further expansion is within the scope of this subclass.
SEE OR SEARCH THIS CLASS, SUBCLASS:
387+, for reshaping a preform or parison by fluid pressure; see the search notes thereto.
817, for an art collection of means designed to mold pore formable material.
SEE OR SEARCH CLASS 264, Plastic and Nonmetallic Article Shaping or Treating: Processes,
41+, for process of forming pores in an article either mechanically or chemically. See the notes and search notes under Search Class 41.
