Patents by Inventor Sai P. Shum

Sai P. Shum 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).

  • Amorphous solid modification of 2,2',2"-nitrilo[triethyl-tris-(3,3',5,5'-tetra-tert-butyl-1,1'-biphenyl- 2,2'-diyl)phosphite]
    Patent number: 5276076
    Abstract: The amorphous solid modification of 2,2',2"-nitrilo[triethyl-tris-(3,3',5,5'-tetra-tert-butyl-1,1'-biphenyl-2, 2'-diyl)phosphite] is obtained by melting said compound and rapidly cooling the melt.The amorphous solid is an effective process stabilizer for polyolefins, particularly polypropylene.
    Type: Grant
    Filed: November 30, 1992
    Date of Patent: January 4, 1994
    Assignee: Ciba-Geigy Corporation
    Inventors: Stephen D. Pastor, Sai P. Shum
  • Process of making 3,7,9-trioxa-1-aza-2,8-diphosphaspiro[4,5]decanes
    Patent number: 5239103
    Abstract: 3,7,9-Trioxa-1-aza-2,8-diphosphaspiro[4.5]decanes of formula I ##STR1## wherein R.sub.1 and R.sub.2 are independently hydrogen, alkyl, cycloalkyl, bicycloalkyl, tricycloalkyl or aryl; or can be halogen when n or m is zero,R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are independently hydrogen, alkyl, aralkyl or aryl;X and Y are independently --O--, --S-- or --NR.sub.16 -- where R.sub.16 is alkyl, cycloalkyl, alkenyl, aryl or aralkyl;W and Z are independently O or S; andn, m, o and p are independently zero or 1, are effective in stabilizing organic materials against the deleterious effects of oxygen, heat and/or actinic radiation.
    Type: Grant
    Filed: November 12, 1992
    Date of Patent: August 24, 1993
    Assignee: Ciba-Geigy Corporation
    Inventors: Raymond Seltzer, Paul A. Odorisio, Sai P. Shum, Stephen D. Pastor
  • Stabilized copositions comprising 3,7,9-trioxa-1-aza-2,8-diphosphaspiro[4,5]decanes
    Patent number: 5187213
    Abstract: 3,7,9-Trioxa-1-aza-2,8-diphosphaspiro[4.5]decanes of formula I ##STR1## wherein R.sub.1 and R.sub.2 are independently hydrogen, alkyl, cycloalkyl, bicycloalkyl, tricycloalkyl or aryl; or can be halogen when n or m is zero,R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are independently hydrogen, alkyl, aralkyl or aryl;X and Y are independently --O--, --S-- or --NR.sub.16 -- where R.sub.16 is alkyl, cycloalkyl, alkenyl, aryl or aralkyl;W and Z are independently O or S; andn, m, o and p are independently zero or 1, are effective in stabilizing organic materials against the deleterious effects of oxygen, heat and/or actinic radiation.
    Type: Grant
    Filed: February 27, 1992
    Date of Patent: February 16, 1993
    Assignee: Ciba-Geigy Corporation
    Inventors: Raymond Seltzer, Paul A. Odorisio, Sai P. Shum, Stephen D. Pastor
  • Substituted 1-oxy-4-acyloxypiperidine and 1-oxy-4-acylaminopiperidine stabilizers
    Patent number: 5185448
    Abstract: Substituted 1-oxy-4-acyloxypiperidines or 1-oxy-4-acylaminopiperidines of formula I ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently hydrogen, alkyl or substituted alkyl, R.sub.5 is hydrogen, alkyl, cycloalkyl, allyl or benzyl, X is --O-- or --NE--, E is hydrogen, alkyl or cycloalkyl, A is an n-valent aliphatic or aromatic hydrocarbon radical, and n is 1 to 4 are effective in providing melt flow stabilization to polymeric materials during processing.
    Type: Grant
    Filed: May 7, 1991
    Date of Patent: February 9, 1993
    Assignee: Ciba-Geigy Corporation
    Inventors: Paul A. Odorisio, Sai P. Shum
  • Compositions stabilized with 3H-1,3,2-oxozaphospholidines
    Patent number: 5147910
    Abstract: Substituted 3H-1,3,2-oxazaphospholidines of formula I ##STR1## where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently hydrogen, alkyl, cycloalkyl, phenylalkyl or aryl, n is 1 to 4 and T is an n-valent aliphatic or aromatic hydrocarbon radical are effective in stabilizing organic materials against the deleterious effects of oxygen, heat and/or actinic radiation.
    Type: Grant
    Filed: September 23, 1991
    Date of Patent: September 15, 1992
    Assignee: Ciba-Geigy Corporation
    Inventors: Paul A. Odorisio, James L. Hyun, Sai P. Shum, Raymond Seltzer
  • Substituted 3,7,9-trioxa-1-aza-2,8-diphosphaspiro(4,5)decanes and stabilized compositions
    Patent number: 5132426
    Abstract: 3,7,9-Trioxa-1-aza-2,8-diphosphaspiro[4.5]decanes of formula I ##STR1## wherein R.sub.1 and R.sub.2 are independently hydrogen, alkyl, cycloalkyl, bicycloalkyl, tricycloalkyl or aryl; or can be halogen when n or m is zero,R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are independently hydrogen, alkyl, aralkyl or aryl;X and Y are independently --O--, --S-- or --NR.sub.16 -- where R.sub.16 is alkyl, cycloalkyl, alkenyl, aryl or aralkyl;W and Z are independently O or S; andn, m, o and p are independently zero or 1, are effective in stabilizing organic materials against the deleterious effects of oxygen, heat and/or actinic radiation.
    Type: Grant
    Filed: May 20, 1991
    Date of Patent: July 21, 1992
    Assignee: Ciba-Geigy Corporation
    Inventors: Raymond Seltzer, Paul A. Odorisio, Sai P. Shum, Stephen D. Pastor
  • Substituted 3,7,9-trioxa-1-aza-2,8-diphosphaspiro[4.5]decanes and stabilized compositions
    Patent number: 5075482
    Abstract: 3,7,9-Trioxa-1-aza-2,8-diphosphaspiro[4.5]decanes of formula I ##STR1## wherein R.sub.1 and R.sub.2 are independently hydrogen, alkyl, cycloalkyl, bicycloalkyl, tricycloalkyl or aryl; or can be halogen when n or m is zero,R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are independently hydrogen, alkyl, aralkyl or aryl;X and Y are independently --O-- --S--, or --NR.sub.16 -- where R.sub.16 is alkyl, cycloalkyl, alkenyl, aryl or aralkyl;W and Z are independently O or S; andn, m, o and p are independently zero or 1, are effective in stabilizing organic materials against the deleterious effects of oxygen, heat and/or actinic radiation.
    Type: Grant
    Filed: August 23, 1990
    Date of Patent: December 24, 1991
    Assignee: Ciba-Geigy Corporation
    Inventors: Raymond Seltzer, Paul A. Odorisio, Sai P. Shum, Stephen D. Pastor
  • 3H-1,3,2-oxazaphospholidines and stabilized compositions
    Patent number: 5075484
    Abstract: Substituted 3H-1,3,2-oxazaphospholidines of formula I ##STR1## where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently hydrogen, alkyl, cycloalkyl, phenylalkyl or aryl, n is 1 to 4 and T is an n-valent aliphatic or aromatic hydrocarbon radical are effective in stabilizing organic materials against the deleterious effects of oxygen, heat and/or actinic radiation.
    Type: Grant
    Filed: August 23, 1990
    Date of Patent: December 24, 1991
    Assignee: Ciba-Geigy Corporation
    Inventors: Paul A. Odorisio, James L. Hyun, Sai P. Shum, Raymond Seltzer