.~ Glass compositions, compositions containing glass other than those wherein glass is a bonding agent, or glass batch forming compositions {11}
39
.~.~ Pore-forming
DEFINITION
Classification: 501/39
Pore-forming:
(under subclass 11) Compositions which are porous, or which are to be further treated to produce multicellular products or processes for producing porous glass products.
(1) Note. To be classified herein, a process or composition must involve a specific step to form the pores. Where the porosity is due merely to the presence of a naturally porous ingredient it is classified on some other basis.
(2) Note. Documents classified as originals in this and indented subclasses are cross-referenced on the basis of the chemical nature of the glass composition disclosed into subclasses 40, 41+, and/or 53+, as appropriate.
(3) Note. Documents classified as originals in this and indented subclasses which disclose optical glass compositions are cross-referenced in subclasses 900+.
SEE OR SEARCH THIS CLASS, SUBCLASS:
80+, for pore-forming of ceramics other than glass compositions.
SEE OR SEARCH CLASS 51, Abrasive Tool Making Process, Material, or Composition,
296, for pore-forming abrasive tool compositions.
65, Glass Manufacturing, especially
20, 22 and 30 for making porous glass by processes which include glass working operations classified in that class (65).
516, Colloid Systems and Wetting Agents; Subcombinations Thereof; Processes of Making, Stabilizing, Breaking, or Inhibiting,
10+, for foam colloid systems or agents for such systems or making or stabilizing such systems or agents, when generically claimed or when there is no hierarchically superior provision in the USPC for the specifically claimed art.
