Patents by Inventor Dorothy L. Roerden

Dorothy L. Roerden 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).

  • Patent number: 6177577
    Abstract: This invention relates to novel dicationic and polycationic monoprimary alcohol compounds and their derivatives, represented by the formula wherein each alk is independently alkyl of 1-8 carbon atoms; each ALK is independently alkyl of 1-8 carbon atoms; each R1, R2, R3, R4 or R5 is independently H or alkyl of 1-8 carbon atoms; n is 2-5; G is H, CR1R2CR3OHCR4R5X or X is Cl, Br or I; An− is an anion and p is 1-10; provided that the compound is soluble in water.
    Type: Grant
    Filed: November 15, 1991
    Date of Patent: January 23, 2001
    Assignee: The Dow Chemical Company
    Inventors: Dorothy L. Roerden, R. Keith Frank
  • Patent number: 6123738
    Abstract: 2,3-Epoxypropyltrimethylammonium chloride having reduced color and method of preparation are disclosed. 2,3-Epoxypropyltrimethylammonium chloride is treated with sodium hypochlorite to reduce its color. 2,3-Epoxypropyltrimethylammonium chloride can be prepared via reaction of trimethylamine and epichlorohydrin. If desired, an aprotic solvent can be used. 2,3-Epoxypropyltrimethylammonium chloride formed in the resultant slurry, must then be isolated via known methods, such as evaporation, extraction, centrifugation, etc, depending upon the other constituents of the slurry and the residual epichlorohydrin removed. The final product is then treated with an effective amount of sodium hypochlorite. The obtained 2,3-epoxypropyltrimethylammonium chloride then is used for, for example, color-sensitive applications such as to produce cationic starch for use in paper manufacture.
    Type: Grant
    Filed: August 19, 1998
    Date of Patent: September 26, 2000
    Assignee: The Dow Chemical Company
    Inventors: Laren P. Childers, Dorothy L. Roerden
  • Patent number: 5616800
    Abstract: This invention relates to novel dicationic and polycationic monoprimary alcohol compounds and their derivatives, represented by the formula ##STR1## wherein each alk is independently alkyl of 1-8 carbon atoms; each ALK is independently alkyl of 1-8 carbon atoms; each R.sub.1, R.sub.2, R.sub.3, R.sub.4 or R.sub.5 is independently H or alkyl of 1-8 carbon atoms; n is 2-5; G is H, CR.sub.1 R.sub.2 CR.sub.3 OHCR.sub.4 R.sub.5 X or ##STR2## X is Cl, Br or I; An.sup.- is an anion and p is 1-10; provided that the compound is soluble in water.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: April 1, 1997
    Assignee: The Dow Chemical Company
    Inventors: Dorothy L. Roerden, R. Keith Frank
  • Patent number: 5320646
    Abstract: A process for improving the dyeability of fabrics or fibers comprising polyhydroxylzed polymers by the use of at least one compound selected from the group consisting of a compound of the formula; ##STR1## and mixtures thereof, wherein R, R', R" and R"' are lower alkyl radicals having 1 to 20 carbon atoms and X is selected from the group consisting of sulfate, sulfonate and halide. The process requires that a dry cauticized fabric be treated with a dilute solution of a lower alkyl ammonium salt so that the fabric contains less than about 50% by weight of water prior to curing.
    Type: Grant
    Filed: April 14, 1993
    Date of Patent: June 14, 1994
    Assignee: The Dow Chemical Company
    Inventors: Robert T. Patton, Stephen E. Hill, Dorothy L. Roerden
  • Patent number: 5241061
    Abstract: A process for dry cationization of starch or a starch-containing material comprises reacting the starch or starch-containing material with a dialkyl(epoxyalkyl)amine or trialkyl(epoxyalkyl) ammonium halide in a medium containing a maximum of 40% by weight of water in the presence of an alkali metal or alkaline earth metal oxide or hydroxide and a finely-divided aluminosilicate clay, having a cation-exchange capacity less than about 15 meq/100 g.
    Type: Grant
    Filed: May 27, 1992
    Date of Patent: August 31, 1993
    Assignee: The Dow Chemical Company
    Inventors: Dorothy L. Roerden, Clara D. Wessels
  • Patent number: 5198117
    Abstract: A process and apparatus for making a low salt epoxide is disclosed. The process comprises feeding a halohydrin solution into one compartment of a dialysis cell separated from a hydroxide dialyzing solution in a second compartment by an anionic membrane. An effective hydroxide concentration gradient across the membrane induces hydroxyl ion exchange for excess anions from the halohydrin solution so that electroneutrality across the membrane can be maintained.
    Type: Grant
    Filed: December 2, 1991
    Date of Patent: March 30, 1993
    Assignee: The Dow Chemical Company
    Inventors: Jeffery G. Grierson, Dorothy L. Roerden