Patents by Inventor Donald L. Caldwell

Donald L. Caldwell 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: 6082921
    Abstract: An improved paint brush having a body, a handle connected to and extending outwardly from the body, a plurality of bristles extending outwardly from the body, and a plug affixed to the body within the plurality of bristles. The plug has a bar and a plurality of tubular members extending from the bar. The bar is a planar member with an edge extending transverse to a longitudinal axis of the handle. The plurality of tubular members includes a first plurality of tubular members arranged on one side of the bar and a second plurality of tubular members arranged on an opposite side of the bar. Each of the first and second pluralities of tubular members has a top opening and a bottom opening. The bottom opening is adjacent to the bar. The top opening communicates with a plenum area formed on the interior of the body. The bar and the plurality of tubular members are integrally formed together of a polymeric material.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: July 4, 2000
    Assignee: Caldwell Industries, Inc.
    Inventor: Donald L. Caldwell
  • Patent number: 5483721
    Abstract: A paint brush having a body, a handle connected to and extending outwardly from the body, a plurality of bristles arranged in a plurality of rows and extending outwardly from the body, a liquid inlet channel formed so as to extend through the body toward the plurality of bristles, and a plenum area formed in the body and connected to the liquid inlet channel. The plenum area has a plurality of outlet orifices formed therein adjacent to an end of the plurality of bristles. These outlet orifices are arranged in a rows between the plurality of bristles. The liquid inlet channel extends at an acute angle relative to a longitudinal axis of the handle. An adapter member is slidably received within the liquid inlet channel. The adapter member has a connector for attachment to an external source of liquid. The adapter member has a threaded end which tapers to an insert member. The insert member is slidably received within the liquid inlet channel.
    Type: Grant
    Filed: December 26, 1994
    Date of Patent: January 16, 1996
    Inventor: Donald L. Caldwell
  • Patent number: 4752369
    Abstract: An electrochemical cell having a hydraulically impermeable permselective membrane is operated more efficiently by (1) separating the anode and the cathode of such a cell from the permselective membrane by a spacing means which is porous, hydrophilic, and electrically non-conductive, or alternatively, (2) providing a coating on the metal electrodes of said cell which is hydrophilic, porous, and electrically non-conductive. Said spacing means is of a material selected from the group consisting of at least one of mineral fibers, synthetic organic polymers, and ceramics and glasses.
    Type: Grant
    Filed: November 5, 1984
    Date of Patent: June 21, 1988
    Assignee: The Dow Chemical Company
    Inventors: Donald L. Caldwell, Kenneth A. Poush
  • Patent number: 4464238
    Abstract: Porous separators for electrolytic processes are designed which are characterized by an N.sub.mac t value, where N.sub.mac is the ratio of the resistance (r) of the electrolyte-saturated separator to the resistance (r.sub.o) of an equivalent volume of electrolyte and t is the thickness, in inches, of the separator. The N.sub.mac value is referred to here as the MacMullin Number.
    Type: Grant
    Filed: May 9, 1983
    Date of Patent: August 7, 1984
    Assignee: The Dow Chemical Company
    Inventors: Donald L. Caldwell, Kenneth A. Poush
  • Patent number: 4442227
    Abstract: Hypochlorite ions in aqueous solution are catalytically decomposed by the action of a poly-metal spinel of cobalt preferably coated on an inert, stable support. The spinel catalyst may contain dispersed therein, optionally, other "modifier" metal oxides which contribute better adherence of the spinel to the substrate and improve the toughness of the spinel coating. The substituted cobalt spinel conforms generally to the empirical formulaM.sub.x N.sub.y Co.sub.3-(x+y) O.sub.4where zero<x.ltoreq.1; zero.ltoreq.y.ltoreq.0.5; M is at least one metal of Periodic Table Groups IB, IIA, and IIB; N is at least one metal from Group IA; and zero<(x+2y).ltoreq.1.
    Type: Grant
    Filed: October 18, 1982
    Date of Patent: April 10, 1984
    Assignee: The Dow Chemical Company
    Inventor: Donald L. Caldwell
  • Patent number: 4430315
    Abstract: Hypochlorite ions in aqueous solution are catalytically decomposed by the action of a poly-metal spinel of cobalt preferably coated on an inert, stable support. The spinel catalyst may contain dispersed therein, optionally, other "modifier" metal oxides which contribute better adherence of the spinel to the substrate and improve the toughness of the spinel coating. The substituted cobalt spinel conforms generally to the empirical formulaM.sub.x N.sub.y Co.sub.3-(x+y) O.sub.4where zero<x.ltoreq.1; zero.ltoreq.y.ltoreq.0.5; M is at least one metal of Periodic Table Groups IB, IIA, and IIB; N is at least one metal from Group IA; and zero<(x+2y).ltoreq.1.
    Type: Grant
    Filed: December 28, 1981
    Date of Patent: February 7, 1984
    Assignee: The Dow Chemical Company
    Inventor: Donald L. Caldwell
  • Patent number: 4428805
    Abstract: Electroconductive substrates for use as oxygen electrodes are coated with an optional interface layer and then with cobalt oxide spinels conforming substantially to the empirical formulaM.sub.x Z.sub.y CO.sub.3.sbsb.-(x+y) O.sub.4where M represents at least one metal from the Groups IB, IIA, IIB, where Z represents at least one metal from Group IA where x is equal to or greater than zero but not greater than 1, where y is equal to or greater than zero but not greater than 0.5, and where (x plus 2y) is equal to or greater than zero but not greater than 1. The composites are prepared by thermally oxidizing metal oxide precursors in-situ on the substrate, including, optionally, modifier metal oxide materials as a separate dispersed phase in the contiguous spinel structure. The interface layer comprises at least one oxide of Pb, Sn, Sb, Al, In, or mixtures of these. The electrodes are used as the anodic means in an electrolysis cell wherein oxygen is produced by electrolyzing an oxygen-containing electrolyte.
    Type: Grant
    Filed: August 24, 1981
    Date of Patent: January 31, 1984
    Assignee: The Dow Chemical Co.
    Inventors: Donald L. Caldwell, Mark J. Hazelrigg, Jr.
  • Patent number: 4369105
    Abstract: Electroconductive substrates are coated with an interface layer and then with cobalt oxide spinels conforming substantially to the empirical formulaM.sub.x Z.sub.y Co.sub.3-(x+y) O.sub.4where M represents at least one metal from the Groups IB, IIA, IIB, where Z represents at least one metal from Group IA where x is equal to or greater than zero but not greater than 1, where y is equal to or greater than zero but not greater than 0.5, and where (x plus 2y) is equal to or greater than zero but not greater than 1. The composites are prepared by thermally oxidizing metal oxide precursors in-situ on the substrate, including, optionally, modifier metal oxide materials as a separate dispersed phase in the contiguous spinel structure. The interface layer comprises at least one oxide of Pb, Sn, Sb, Al, In, or mixtures of these.
    Type: Grant
    Filed: March 25, 1981
    Date of Patent: January 18, 1983
    Assignee: The Dow Chemical Company
    Inventors: Donald L. Caldwell, Mark J. Hazelrigg, Jr.
  • Patent number: 4368110
    Abstract: Electroconductive substrates are coated with substituted cobalt oxide spinels conforming substantially to the empirical formulaM.sub.x Z.sub.y Co.sub.3-(x+y) O.sub.4where M and Z each represent at least one metal from the Groups IB, IIA, IIB, where x and y each, independently are values greater than zero but less than 1, and where x plus y is not greater than 1. The composites are prepared by thermally oxidizing metal oxide precursors in-situ on the substrate, including, optionally, modifier metal oxide materials as a separate dispersed phase in the contiguous spinel structure. The composites are useful, e.g., as an anode material in an electrolytic cell.
    Type: Grant
    Filed: March 25, 1981
    Date of Patent: January 11, 1983
    Assignee: The Dow Chemical Company
    Inventors: Donald L. Caldwell, Mark J. Hazelrigg, Jr.
  • Patent number: 4366042
    Abstract: Electroconductive substrates are coated with substituted cobalt oxide spinels conforming substantial to the empirical formulaM.sub.x Z.sub.y Co.sub.3-(x+y) O.sub.4where M comprises at least one metal from the Groups IB, IIA, IIB, where Z comprises at least one metal from Group IA, where x is equal to or greater than zero but less than one, where y is greater than zero but not greater than 0.5, and where x plus 2y is not greater than 1. The composites are prepared by thermally oxidizing metal oxide precursors in-situ on the substrate, including, optionally, modifier metal oxide materials as a separate dispersed phase in the continuous spinel structure.
    Type: Grant
    Filed: March 25, 1981
    Date of Patent: December 28, 1982
    Assignee: The Dow Chemical Company
    Inventors: Donald L. Caldwell, Mark J. Hazelrigg, Jr.
  • Patent number: 4312723
    Abstract: An electrolytic cell and its method of operation is described. The cell comprises an anode, a cathode and iron-containing metals exposed to the interior portions of the cell which are maintained at about the same electrical potential as the cathode. These materials are covered with a protective coating to minimize corrosion during operation of the cell.
    Type: Grant
    Filed: June 9, 1980
    Date of Patent: January 26, 1982
    Assignee: The Dow Chemical Company
    Inventors: John M. McIntyre, Donald L. Caldwell
  • Patent number: 4279709
    Abstract: Electrodes with porous coatings are produced using an inorganic compound which is soluble in an aqueous solution, as the pore former in the coating. The inorganic pore former may be removed from the coating while the electrode is being used in an electrolytic cell without contaminating the electrolyte. Such electrodes are particularly useful in electrolytic cells, wherein they operate at a significantly lower voltage and have a longer life span than conventional electrodes.
    Type: Grant
    Filed: May 8, 1979
    Date of Patent: July 21, 1981
    Assignee: The Dow Chemical Company
    Inventors: John M. McIntyre, Donald L. Caldwell
  • Patent number: 4142005
    Abstract: Electrodes particularly suitable for use as anodes in electrolytic cells are prepared by coating an electrically-conductive substrate with a thermally-decomposable inorganic cobalt compound and then thermally oxidizing the inorganic cobalt compound under conditions at which the single-metal spinel, Co.sub.3 O.sub.4, is formed.
    Type: Grant
    Filed: February 27, 1976
    Date of Patent: February 27, 1979
    Assignee: The Dow Chemical Company
    Inventors: Donald L. Caldwell, Mark J. Hazelrigg, Jr.
  • Patent number: 4073873
    Abstract: Hypochlorite ions in aqueous solution are catalytically decomposed by the action of a single-metal spinel of Co.sub.3 O.sub.4, preferably coated on an inert, stable support. The Co.sub.3 O.sub.4 catalyst may contain dispersed therein, optionally, other "modifier" metal oxides which do not affect the single-metal spinel structure of the Co.sub.3 O.sub.4, but which contribute better adherence of the Co.sub.3 O.sub.4 to the substrate and improve the toughness of the Co.sub.3 O.sub.4 coating.
    Type: Grant
    Filed: March 29, 1976
    Date of Patent: February 14, 1978
    Assignee: The Dow Chemical Company
    Inventors: Donald L. Caldwell, Raymond J. Fuchs, Jr.
  • Patent number: H544
    Abstract: Impressed current cathodic protection systems employing an anode having a cobalt spinel type surface, said surface having the formula: M.sub.x Z.sub.y Co.sub.(3-(x+y)) O.sub.4, where M is a metal or a mixture of two or more metals selected from the group of metals contained in Groups IB, IIA, and IIB of the periodic table of the elements, where Z is a metal or a mixture of two or more metals selected from the group of metals contained in Group IA of the periodic table of the elements, where 0.ltoreq.x.ltoreq.1, where 0.ltoreq.y.ltoreq.0.5, and where 0.ltoreq.(x+2y).ltoreq.1.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: November 1, 1988
    Assignee: The Dow Chemical Company
    Inventors: Raul A. Castillo, Donald L. Caldwell, Ralph W. Parham, Jr.