Patents by Inventor John F. Clifford

John F. Clifford 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).

  • Glass compositions
    Patent number: 5308803
    Abstract: A glass composition which is essentially free from lead and cadium comprises, in mole percent, SiO.sub.2 :35 to 75%, Bi.sub.2 O3:0.1 to 15%, Al.sub.2 O.sub.3 :0.1 to 10%, B.sub.2 O.sub.3 :1 to 30%, at least one of Li.sub.2 O, Na.sub.2 O, K.sub.2 O:5 to 30%, ZrO.sub.2 :0.1 to 10%, and certain other optional ingredients, with the proviso that BaO and ZnO are not contained in an amount of more than 2 mole percent. These glass compositions can be used as fluxes for mixing with pigments to provide compositions for the decoration of ceramic materials and/or glass.
    Type: Grant
    Filed: June 10, 1992
    Date of Patent: May 3, 1994
    Assignee: Cookson Group PLC
    Inventors: John F. Clifford, Ivan Wozniak, Peter J. Smith
  • Glaze compositions
    Patent number: 5304516
    Abstract: Glaze composition comprises 45 to 75% of SioO.sub.2, 0.1 to below 5% of Bi.sub.2 O.sub.3, 0.1 to 20% of Al.sub.2 O.sub.3 to 20% of B.sub.2 O.sub.3, at least one of CaO, MgO, SrO, BaO or Zno in an amount of 2 to 22%, at least one of Li.sub.2 O, Na.sub.2 O, K.sub.2 O in an amount of 1 to 10%, at least one of La.sub.2 O.sub.3, MoO.sub.3 or WO.sub.3 in an amount of 0.1 to 10% and certain other optional ingredients, all percentages being percentages by weight based on the total weight of the glaze composition, the glaze composition having a firing temperature of 950.degree. to 1250.degree. C., and having a coefficient of thermal expansion of 50 to 100.times.10.sup.-7 /.degree.C.
    Type: Grant
    Filed: April 16, 1992
    Date of Patent: April 19, 1994
    Assignee: Cookson Group PLC
    Inventor: John F. Clifford
  • Sintering aid
    Patent number: 5262368
    Abstract: A method of sintering a ceramic material composed of alkaline earth metal titanate and mixtures thereof, wherein the ceramic material is mixed with a sintering aid of a mixture of a mixed metal oxide of the formula BaCuO.sub.2 and an oxide selected from the group consisting of tungsten trioxide, molybdenum trioxide and mixtures thereof, and sintering the mixture.
    Type: Grant
    Filed: November 19, 1991
    Date of Patent: November 16, 1993
    Assignee: TAM Ceramics, Inc.
    Inventors: Christopher Hood, John F. Clifford, Timothy P. Beales, John Bultitude
  • Glaze compositions
    Patent number: 5244848
    Abstract: Glaze composition for use on bone china and fine china which is essentially free from lead and cadium comprises, by weight, SiO.sub.2 : 35 to 60%, Bi.sub.2 O.sub.3 : 5 to 45%, Al.sub.2 O.sub.3 :5 to 20%, B.sub.2 O.sub.3 : 1 to 15%, at least one of CaO, MgO, SrO or BaO: 2 to 20%, at least one of Li.sub.2 O, Na.sub.2 O, K.sub.2 O: 1 to 10%, and certain other optional ingredients, with the proviso that BaO is not contained in an amount of more than 2% by weight.
    Type: Grant
    Filed: January 13, 1993
    Date of Patent: September 14, 1993
    Assignee: Cookson Group PLC
    Inventors: John F. Clifford, Ivan Wozniak
  • Glaze compositions
    Patent number: 5200369
    Abstract: Glaze composition for use on bone china and fine china which is essentially free from lead and cadium comprises, by weight, SiO.sub.2 :35 to 60%, Bi.sub.2 O.sub.3 :5 to 45%, Al.sub.2 O.sub.3 :5 to 20%, B.sub.2 O.sub.3 :1 to 15%, at least one of CaO, MgO, SrO or BaO:2 to 20%, at least one of Li.sub.2 O, Na.sub.2 O, K.sub.2 O:1 to 10%, and certain other optional ingredients, with the proviso that BaO is not contained in an amount of more than 2% by weight.
    Type: Grant
    Filed: April 9, 1991
    Date of Patent: April 6, 1993
    Assignee: Cookson Group PLC
    Inventors: John F. Clifford, Ivan Wozniak
  • Pigment compositions
    Patent number: 4898619
    Abstract: A pigment which comprises crystallites of iron oxide having an average particle size of less than 100 nanometers doped with from 10% to 80% by weight of aluminium as Al.sup.3+ based on the weight of iron, having the general formula (Al.sub.x Fe.sub.2-x)O.sub.3, where x=0.34 to 1.24 and having an orange color with the following color measurements:L (Lightness)>45.degree.C (Strength)>40.degree.H (Hue) 50.degree. to 60.degree.A pigment precursor composition is also provided which, on firing, produces the pigment as defined above.
    Type: Grant
    Filed: December 19, 1988
    Date of Patent: February 6, 1990
    Assignee: Cookson Group PLC
    Inventors: John F. Clifford, Fiona C. R. Morrison