Abstract: Intersticed materials, including woven and nonwoven fabrics, open-cellular materials and the like, are impregnated with functional substances by incorporating the substances in microscopic porous particles in which the pores form an interconnected network open to the particles in the interstices of the materials. The functional substances thus impart useful properties to the material in a controlled release manner.

Abstract: Articles for use in contact with animal tissue, such as surgical and first aid supplies, health care products and personal hygiene products, are dusted with microspheres for lubricating purposes or for the application of diffusible adjuvants. In the latter case, the microspheres are porous, with a continuous network of pores open to the exterior of the particles, permitting outward diffusion of the adjuvants at a controlled rate depending on pore size. The adjuvants include such substances as biologically active substances, deodorants, flavors, fragrances, and liquid lubricants.