Liquefied-Gas-Containing Containers for Use with Gas Pressure-Operated Dusting Instruments; Water-Soluble Spray Adhesives for Mounting Prints or Art on Porous Surfaces; Water-Removable Chemical Sprays to Subdue Glaring Highlights on Metal, Glass, Plastic and Other Surfaces; Chemical Sprays to Provide a Permanent Matted Finish to Paper, Metal, Glass, Leather, Plastic and Other Surfaces; Gas-Blast Dust Removers; Gas-Blast Static and Dust Removers