Patents Represented by Attorney W. C. Mitchell
  • Patent number: 5068279
    Abstract: A melamine-formaldehyde detackifer having less than 0.15% free formaldehyde comprises a melamine-formaldehyde polymer detackifier to which has been added a formaldehyde scavenging agent comprising an effective amount of urea, and an enhancer selected from glyoxal and acetylacetone. The use of the low free formaldehyde detackifier is also described.
    Type: Grant
    Filed: March 30, 1990
    Date of Patent: November 26, 1991
    Assignee: Calgon Corporation
    Inventor: Lewis D. Morse
  • Patent number: 5047078
    Abstract: This invention relates to the use of traditional scale inhibitors as fertilizers enhancers. More particularly, this invention relates to compositions which comprise: (a) a phosphate fertilizer and (b) a scale inhibiting compound. Further, this invention relates to a method of stimulating and increasing plant growth, and corresponding yields, comprising adding the above-defined compositions to the soil in which the plants being treated grow.
    Type: Grant
    Filed: May 2, 1985
    Date of Patent: September 10, 1991
    Assignee: Calgon Corporation
    Inventor: Jasbir S. Gill
  • Patent number: 5035808
    Abstract: The use as flocculants of ferric salt/water-soluble cationic polymer compositions having inorganic:polymer weight ratios of at least 5:1 is disclosed. These compositions are especially effective in low turbidity waters.
    Type: Grant
    Filed: September 12, 1989
    Date of Patent: July 30, 1991
    Assignee: Calgon Corporation
    Inventors: Denis E. Hassick, Joseph P. Miknevich
  • Patent number: 5034405
    Abstract: The instant invention is directed to synergistic antimicrobial admixtures comprising 2-bromo-2-bromomethylglutaronitrile, 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one and its use in inhibiting microbial growth.
    Type: Grant
    Filed: May 13, 1986
    Date of Patent: July 23, 1991
    Assignee: Calgon Corporation
    Inventor: John A. Jakubowski
  • Patent number: 5032526
    Abstract: The instant invention is directed to a method for determining the concentration of sulfonate and/or polycarboxylate compounds in an aqueous solution comprising:(a) adjusting the pH of a portion of the aqueous solution to less than 3.0 when measuring sulfonate concentration or to between 3.0 and 12.0 when measuring polycarboxylate concentration;(b) adding an effective amount of an aqueous solution containing a metachromatic dye to the pH-adjusted portion of Step (a);(c) measuring the absorbance of the admixture resulting from Step (b) at a wavelength between 300 nm and 700 nm; and(d) comparing the absorbance from Step (c) with absorbances of standard samples containing known concentrations of sulfonate and/or polycarboxylate compounds and said effective amount of the dye solution of Step (b), thereby determining the sulfonate and/or polycarboxylate concentration of the portion of Step (a).
    Type: Grant
    Filed: January 11, 1990
    Date of Patent: July 16, 1991
    Assignee: Calgon Corporation
    Inventors: Ronald R. Myers, Jack E. Fink
  • Patent number: 5015390
    Abstract: This invention is directed to a method for controlling the formation of scale deposits in aqueous systems by adding an effective amount, preferably at least 0.1 ppm, of a maleic anhydride/quaternary ammonium-type polymer to the aqueous system being treated.
    Type: Grant
    Filed: March 12, 1990
    Date of Patent: May 14, 1991
    Assignee: Calgon Corporation
    Inventors: Shih-Ruey T. Chen, Craig W. Vaughan
  • Patent number: 5015395
    Abstract: A method for controlling zebra mussels in aqueous systems comprising treating aqueous systems which contain zebra mussels or which are prone to zebra mussel infestation with an effective amount of a water-soluble dialkyl diallyl quaternary ammonium polymer (polyquat). A preferred polymer is a poly(quaternary ammonium) compound having the recurring structure [DMDAAX.sup.- ] resulting from the polymerization of monomeric dimethyl diallyl ammonium X.sup.-, wherein X.sup.- is any suitable anion.
    Type: Grant
    Filed: April 18, 1990
    Date of Patent: May 14, 1991
    Assignee: Calgon Corporation
    Inventors: Ramon A. Muia, Rodney M. Donlan
  • Patent number: 5000856
    Abstract: This invention is directed to a method for controlling the formation of scale deposits in aqueous systems operated at high pH and/or calcite saturation levels by adding an effective amount, preferably at least 0.1 ppm, of an allyl sulfonate/maleic anhydride polymer to the aqueous system being treated.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: March 19, 1991
    Assignee: Calgon Corporation
    Inventors: Shih-Ruey T. Chen, Craig W. Vaughan
  • Patent number: 4990261
    Abstract: A method for monitoring and/or controlling a liquid/solid separation process is described. The method utilizes photodetectors to view the surface of the composition being dewatered, and correlate the corresponding signals from the photodetectors to dryness values.This is a continuation of application Ser. No. 122,976, filed Nov. 19, 1987 now abandoned.
    Type: Grant
    Filed: March 28, 1989
    Date of Patent: February 5, 1991
    Assignee: Calgon Corporation
    Inventor: Bosco P. Ho
  • Patent number: 4936987
    Abstract: The instant invention is directed to an admixture, and its use in inhibiting scale and corrosion in aqueous systems, comprising:(a) a water-soluble polymer having a weight average molecular weight of less than 25,000, as determined by low angle laser light scattering, comprising an unsaturated carboxylic acid and an unsaturated sulfonic acid, or their salts, having a ratio of 1:20 to 20:1, and(b) at least one compound selected from the group consisting of water-soluble polycarboxylates, phosphonates, phosphates, polyphosphates, metal salts and sulfonates.The instant invention is also directed to a method of inhibiting the formation of insoluble alluvial, metal oxide and metal hydroxide deposits in an aqueous system, comprising adding to the system at least 0.
    Type: Grant
    Filed: May 16, 1988
    Date of Patent: June 26, 1990
    Assignee: Calgon Corporation
    Inventors: Leonard J. Persinski, Jerry L. Walker, Bennett P. Boffardi
  • Patent number: 4935149
    Abstract: A melamine-formaldehyde detackifer having a less than 0.15% free formaldehyde which comprises a melamine-formaldehyde polymer detackifier to which has been added a formaldehyde scavenging agent selected from an effective amount of urea, acetylacetone, and a combination of urea with an enhancer selected from glyoxal and acetylacetone. The use of the low free formaldehyde detackifier is also described.
    Type: Grant
    Filed: January 12, 1989
    Date of Patent: June 19, 1990
    Assignee: Calgon Corporation
    Inventor: Lewis D. Morse
  • Patent number: 4933090
    Abstract: This invention is directed to a method for controlling the formation of silica/silicate deposits in aqueous systems by adding an effective amount, preferably at least 0.1 ppm, of a designated phosphonate and, optionally, a carboxylic/sulfonic polymer or salt thereof to the aqueous system being treated. Borate or molybdate ion sources may also be added.
    Type: Grant
    Filed: December 28, 1988
    Date of Patent: June 12, 1990
    Assignee: Calgon Corporation
    Inventors: Jasbir S. Gill, Susan P. Rey, John H. Wiernik
  • Patent number: 4925568
    Abstract: A method of inhibiting scale in boilers is disclosed whereby high and low molecular weight blends of acrylic acid/acrylamide-type polymers are used to prevent boiler scaling. These polymer blends demonstrate synergistic hydrothermal stability and threshold scale inhibition characteristics at elevated temperatures and pressures.
    Type: Grant
    Filed: February 21, 1989
    Date of Patent: May 15, 1990
    Assignee: Calgon Corporation
    Inventor: Lewis D. Morse
  • Patent number: 4908100
    Abstract: A method of improving the retention of starch in papermaking using blends of high and low molecular weight acrylic acid/acrylamide copolymers.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: March 13, 1990
    Assignee: Calgon Corporation
    Inventors: W. E. Hunter, Ronald J. Falcione
  • Patent number: 4904715
    Abstract: The instant invention is directed to a method for preparing free-flowing, water-soluble polymer gels comprising:(a) reducing the size of water-soluble polymer gels by a size-reduction means, so as to produce polymer gel particles which are less than 1/2 inch in their longest dimension; and(b) adding to the size-reduced polymer gels of Step (a) 0.001 to 20 percent, by weight, of an amphipathic compound, thereby reducing the adhesion of said gel particles to themselves and other substances.
    Type: Grant
    Filed: August 11, 1988
    Date of Patent: February 27, 1990
    Assignee: Calgon Corporation
    Inventors: Wood E. Hunter, Gary P. Craun
  • Patent number: 4895703
    Abstract: A method for inhibiting corrosion due to dissolved oxygen wherein trihydroxybenzene compounds, alone or in combination with conventional oxygen scavengers, preferably hydroquinone, are added to boiler water to prevent corrosion by reducing dissolved oxygen levels in boiler feedwater.
    Type: Grant
    Filed: August 15, 1988
    Date of Patent: January 23, 1990
    Assignee: Calgon Corporation
    Inventors: John D. Zupanovich, Lois J. Neil, Dennis J. Sepelak
  • Patent number: 4894346
    Abstract: The instant invention is directed to a method for determining the concentration of sulfonate and/or polycarboyxlate compounds in an aqueous solution comprising:(a) adjusting the pH of a portion of the aqueous solution to less than 3.0 when measuring sulfonate concentration or to between 3.0 and 12.0 when measuring polycarboxylate concentration;(b) adding an effective amount of an aqueous solution containing a metachromatic dye to the pH-adjusted portion of Step (a);(c) measuring the absorbance of the admixture resulting from Step (b) at a wavelength between 300 nm and 700 nm; and(d) comparing the absorbance from Step (c) with absorbances of standard samples containing known concentrations of sulfonate and/or polycarboxylate compounds and said effective amount of the dye solution of Step (b), thereby determining the sulfonate and/or polycarboxylate concentration of the portion of Step (a).
    Type: Grant
    Filed: October 11, 1983
    Date of Patent: January 16, 1990
    Assignee: Calgon Corporation
    Inventors: Ronald R. Myers, Jack E. Fink
  • Patent number: 4880471
    Abstract: An improved method for detackifying over-sprayed paint, lacquer or enamel entrained in the circulating water of paint spray booths comprises maintaining in the wash water a small amount of an alkaline zinc solution containing ammonium hydroxide and ammonium chloride.
    Type: Grant
    Filed: June 22, 1988
    Date of Patent: November 14, 1989
    Assignee: Calgon Corporation
    Inventor: Herbert J. Kaiser
  • Patent number: 4874527
    Abstract: This invention is directed to a method for controlling the formation of silica/silicate deposits in aqueous systems by adding an effective amount, preferably at least 0.1 ppm, of an imine polymer, a phosphonate and, optionally, a source of molybdate or borate ions to the aqueous system being treated.
    Type: Grant
    Filed: April 28, 1988
    Date of Patent: October 17, 1989
    Assignee: Calgon Corporation
    Inventor: Jasbir S. Gill
  • Patent number: 4867945
    Abstract: The present invention is directed to a method of inhibiting the corrosion of copper and copper alloys in an aqueous system containing oxygen using an effective amount of a polymer prepared from:(A) about 30 to about 70%, by weight, of acrylic acid or methacrylic acid;(B) about 30 to about 70%, by weight, of 2-acrylamido-2-methylpropylsulfonic acid or 2-methacrylamido-2-methylpropylsulfonic acid; and(C) about 15 to about 25%, by weight, of 2-acrylamido-2-methylpropylphosphonic acid or 2-methacrylamido-2-methylpropylphosphonic acid, acrylamide or methacrylamide; wherein the polymer has an intrinsic viscosity of from about 0.05 to about 4.5 dl/g, in 1.0 M NaCl.
    Type: Grant
    Filed: October 13, 1987
    Date of Patent: September 19, 1989
    Assignee: Calgon Corporation
    Inventors: Nancy S. Sherwood, Nicholas J. Alfano