Patents Assigned to Pierce & Stevens Corp.
  • Patent number: 4902722
    Abstract: Syntactic foam graphic arts print media are provided which are particularly suitable for application to a substrate using high speed mechanical printing processes. The invention involves adding to a basic print medium a minor amount of pre-expanded, nonfriable, thermoplastic polyvinylidene chloride based microspheres substantially heat stable between about -20.degree. C. and 175.degree. C., having a particle size to about 10 to 100 microns in diameter, to produce syntactic foams having unlimited shelflife stability. The print media thereby produced may be applied to any known substrate in any desired graphic pattern.
    Type: Grant
    Filed: June 9, 1988
    Date of Patent: February 20, 1990
    Assignee: Pierce & Stevens Corp.
    Inventor: George E. Melber
  • Patent number: 4829094
    Abstract: Microsphere wet cake is mixed with a processing aid effective to prevent agglomeration and surface bonding of the microspheres, and thereafter removing water by drying with continuous mixing, optionally also under reduced pressure, i.e. vacuum drying. By the control of the application of heat and balancing temperature and the mixing, and optionally also the reduced pressure, it is possible to also control expansion of the microspheres from substantially none to substantially theoretical limits of expansion.The processing aid in the present invention is any one of a wide diversity of materials which meet the requirements of the intended function, i.e. to prevent the agglomeration of the microspheres during the process. Suitable materials include, by way of example, dry inorganic pigments or filler materials, and the like, and related organic materials.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: May 9, 1989
    Assignee: Pierce & Stevens Corp.
    Inventors: George E. Melber, William A. Oswald, Leon E. Wolinski