Patents by Inventor Charles W. Sandefur

Charles W. Sandefur 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: 6403797
    Abstract: This invention relates to a process for preparing perylene pigment compositions by (a) reacting, at a temperature of less than about 25° C., a mixture of (1) a perylene tetracarboxylic compound, (2) at least about 0.1% by weight, relative to the perylene tetracarboxylic compound, of a surfactant of formula (I)  wherein R1, R2, R3, X, Y, Z, and Z′ are defined herein, (3) an equivalent excess, relative to the amount of the perylene tetracarboxylic compound, of ammonia or a primary amine RA—NH2, wherein RA is defined herein, and (4) optionally, a solvent,  to form a perylene intermediate; (b) heating the perylene intermediate at a temperature of about 50° C. to about 250° C., optionally in the presence of certain non-pigmentary cyclic anhydrides or imides and/or solvents; and (c) collecting the perylene pigment composition.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: June 11, 2002
    Assignee: Bayer Corporation
    Inventors: Charles W. Sandefur, Brian L. Thompson, Michael J. Greene, Gregory R. Schulz
  • Patent number: 5922123
    Abstract: This invention relates to a process for preparing pigment compositions by conditioning an organic pigment, at about 50 to about 200.degree. C., with(1) at least about 0.1% by weight, relative to the organic pigment, of one or more surfactants of formula (I) ##STR1## wherein R.sup.1 is a C.sub.8 -C.sub.30 aliphatic group optionally having one or more carbon atoms in the main chain replaced with --O--, --S--, --CONH--, --NHCO--, --CH.dbd.CH--, C.sub.5 -C.sub.7 cycloalkylene, phenylene, or --OSi(C.sub.1 -C.sub.4 alkyl).sub.2 -,R.sup.2 is hydrogen, C.sub.1 -C.sub.6 alkyl, or C.sub.1 -C.sub.6 hydroxyalkyl,R.sup.3 is hydrogen, C.sub.1 -C.sub.6 alkyl, or C.sub.1 -C.sub.6 hydroxyalkyl, or R.sup.2 and R.sup.3 together are C.sub.4 -C.sub.7 alkylene, andX is a direct bond, or X and R.sup.2 form a five- to seven-membered heterocyclic ring (and R.sup.3 can form a double bond in X), or X, R.sup.2, and R.sup.
    Type: Grant
    Filed: December 17, 1997
    Date of Patent: July 13, 1999
    Assignee: Bayer Corporation
    Inventors: Charles W. Sandefur, Charles E. Shannon, Brian L. Thompson
  • Patent number: 5900050
    Abstract: This invention relates to a process for preparing pigment compositions by conditioning an organic pigment, at about 50 to about 200.degree. C., with(1) at least about 0.1% by weight, relative to the organic pigment, of one or more surfactants of formula (I) and/or formula (II) ##STR1## and/or ##STR2## wherein R.sup.1, R.sup.2, R.sup.3, X, Y, Z, and Z' are defined herein; and (2) about 1 to about 100 parts by weight, per part by weight of the organic pigment, of a liquid in which the organic pigment is substantially insoluble.
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: May 4, 1999
    Assignee: Bayer Corporation
    Inventors: Michael D. Hayden, Charles W. Sandefur, Abdul Sattar, Charles E. Shannon, Brian L. Thompson
  • Patent number: 5120858
    Abstract: This invention relates to a process for preparing trimethine dyestuffs of the formula ##STR1## wherein R.sup.1 is lower alkyl; R.sup.2 is hydrogen, alkyl, cycloalkyl, aryl, aralkyl, alkoxy, cycloalkoxy, aryloxy, aralkoxy, fluorinated alkyl, alkanoyl, aroyl, alkoxycarbonyl, aryloxycarbonyl, aralkoxycarbonyl, alkanoylamino, aroylamino, alkylaminocarbonyl, arylaminocarbonyl, alkoxycarbonylamino, alkylsulfonyl, arylsulfonyl, halogen, cyano, nitro, carbamoyl, or sulfonamido, or two R.sup.2 together form a fused benzene ring; n is an integer of from 1 to 4; and A.sup.- is an anion, by reacting a mixture of(a) an indoline compound of the formula ##STR2## (b) 1.25 to 1.8 parts by moles, based on the indoline compound, of acetic anhydride; and (c) 0.5 to 0.75 parts by moles, based on the indoline compound, of formic acid to form the dyestuff.
    Type: Grant
    Filed: March 25, 1991
    Date of Patent: June 9, 1992
    Assignee: Miles Inc.
    Inventors: Charles W. Sandefur, Brian L. Thompson, James J. Good
  • Patent number: 4802888
    Abstract: The present invention is concerned with improving the solubility of anionic water soluble dyestuff powders. The solubility of these powders particularly in cold water, is enhanced by adding (i) a chelating agent which has at least two free acid groups and (ii) a Lewis base in an amount sufficient to bring the pH of the water solution of the powder to a value of about 7-10.
    Type: Grant
    Filed: November 6, 1987
    Date of Patent: February 7, 1989
    Assignee: Mobay Corporation
    Inventors: Charles W. Sandefur, Thomas J. Thomas
  • Patent number: 4673410
    Abstract: The present disclosure is concerned with enhancing the solubility of dispersed anionic dyes upon the dilution of their dispersions with room temperature water. Concentrated dispersions of such dyes with acceptable stability and low shear viscosities are disclosed which are more readily diluted to dissolve the dispersed dyestuff because they contain certain chelating agents are described. These agents have at least one free or appropriately neutralized acid group, with carboxylic acid groups being preferred. The appropriae cations include ammonium or lithium ions. The free acid groups are subsequently neutralized with these appropriae cations so that the final dispersions are preferably about neutral, i.e have pH values about 7. A further improvement to the dilutability by the addition of a surfactant, preferably a non-ionic surfactant, is also discssed.
    Type: Grant
    Filed: November 19, 1985
    Date of Patent: June 16, 1987
    Assignee: Mobay Corporation
    Inventors: Charles W. Sandefur, Thomas J. Thomas
  • Patent number: 4474577
    Abstract: The present disclosure is concerned with new modifications of the dyestuff Color Index Acid Blue 324 which have significant advantages over the known form of this dyestuff. In particular, the preferred modification is much easier to isolate from an aqueous medium by filtration and the isolated product has a higher purity. The filtration proceeds much more rapidly and gives a filter residue of a much higher solids content. Furthermore, this new form of the dyestuff imparts a dramatically lower viscosity to aqueous dispersions or slurries prepared from it than are obtained using the old form of this dyestuff. These modifications are obtained by heating an aqueous dispersion or slurry of the known form of Color Index Acid Blue 324 to temperatures in excess of about 97.degree. C. and for the preferred form in the presence of a substance which reduces the surface tension between the dispersed organic dyestuff phase and the aqueous dispersing medium.
    Type: Grant
    Filed: October 26, 1983
    Date of Patent: October 2, 1984
    Assignee: Mobay Chemical Corporation
    Inventors: Charles W. Sandefur, Thomas J. Thomas
  • Patent number: 4468230
    Abstract: The present disclosure is concerned with aqueous dispersions of anionic acid dyes, especially the monosulphonated level dyeing acid dyes, which have low room temperature, low shear viscosities and good storage stability. This low viscosity enables them to be readily poured, pumped and otherwise handled. These dispersions comprise dyestuff solids with a controlled particle size distribution having a median value between about 1 and 10 microns; an anionic dispersant; and an electrolyte. In a preferred embodiment the pH is adjusted to give an optimum viscosity value. Another preferred feature is the adjustment of the rheology with a thickening agent such as xanthan gum. These dispersions find particular utility in the continuous dyeing of carpet, especially in Kuesters or foam dyeing equipment.
    Type: Grant
    Filed: March 25, 1983
    Date of Patent: August 28, 1984
    Assignee: Mobay Chemical Corporation
    Inventors: Thomas J. Thomas, Robert G. Hoguet, Charles W. Sandefur, Dietmar Kalz
  • Patent number: 4327998
    Abstract: This invention relates to the preparation of low foam generating and/or low dusting dyestuff or fluorescent whitening agent formulations by continuous introduction of defoaming and/or dedusting agents into the feed stream carrying the aqueous dyestuff or fluorescent whitening agent preparation to a drying apparatus.
    Type: Grant
    Filed: March 19, 1981
    Date of Patent: May 4, 1982
    Assignee: Mobay Chemical Corporation
    Inventors: Charles W. Sandefur, Donald F. Lindow, Thomas J. Thomas
  • Patent number: 3986979
    Abstract: A process for making a wetting-dispersing agent whereby an aqueous mixture of a sulfonated lignin dispersing agent and an anionic or nonionic wetting agent in a weight ratio of dispersing agent to wetting agent of from about 19:1 to 1:3 are dried together to form a single product for use as a surfactant in pesticide formulations.
    Type: Grant
    Filed: September 23, 1971
    Date of Patent: October 19, 1976
    Assignee: Westvaco Corporation
    Inventors: Howard H. Moorer, Charles W. Sandefur