Patents by Inventor Yin Z. Hessefort

Yin Z. Hessefort has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Photostable sunscreen compositions containing dibenzoylmethane derivative, E.G., parsol.RTM. 1789, and diesters or polyesters of naphthalene dicarboxylic acid photostabilizers and enhancers of the sun protection factor (SPF)
    Patent number: 5993789
    Abstract: A sunscreen composition containing a UV-A dibenzoylmethane derivative, such as 4-(1,1-dimethylethyl)-4'-methoxydibenzoylmethane (PARSOL.RTM. 1789), and a stabilizer for the dibenzoylmethane derivative having formula (I) or (II), or mixtures: ##STR1## wherein each R.sup.1, same or different, is an alkyl group having 1 to 22 carbon atoms, a diol having the structure HO--R.sup.2 --OH, or a polyglycol having the structure HO--R.sup.3 --(--O--R.sup.2 --).sub.m --OH, wherein R.sup.2 and R.sup.3, same or different, are each an alkylene group, straight chain or branched, having 1 to 6 carbon atoms, and wherein m and n are each 1 to about 100, or a mixture thereof. These diesters and polyesters of formula (I) or (II) are quite effective in stabilizing the dibenzoylmethane derivative UV-A filter compounds making them more effective, and effective for longer periods of time.
    Type: Grant
    Filed: March 25, 1999
    Date of Patent: November 30, 1999
    Assignee: The C.P. Hall Company
    Inventors: Craig A. Bonda, Peter J. Marinelli, Yin Z. Hessefort, Jagdish Trivedi, Gary Wentworth