Ribbon With Modified Polyethylene Terephthalate Substrate
Original Publication Date: 1984-Jun-01
Included in the Prior Art Database: 2005-Feb-04
Suitable multistrike impact typewriter ribbons can be a produced using substrate manufactured by the extrusion of 0.3 mil (0.0003 inch) polyethylene terephthalate glycol copolyester resin (PETG also known as glycol modified polyethylene terephthalate). PETG offers improved flexibility without plasticization. Synthesis of PETG is similar to that of standard polyethylene terephthalate (PET) except that more than one dibasic acid or glycol or both are copolymerized. Typically, the PETGs are clear, amorphous films with excellent toughness and chemical resistance to oils and solvents. The surface properties of the PETG films are similar to those of commercial PET film of corresponding composition and molecular weight. The active layer for multistrike may be the matrix or spongeous type generally as disclosed in U.S. Patent 3,413,184.