Patents by Inventor Kai Hwa Chew

Kai Hwa Chew 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).

  • Methods of purifying nanostructures
    Patent number: 10843273
    Abstract: The present invention relates to methods of purifying nanostructures. The nanostructures may be silver nanowires.
    Type: Grant
    Filed: November 11, 2016
    Date of Patent: November 24, 2020
    Assignee: QUANTUM CHEMICAL TECHNOLOGIES (SINGAPORE) PTE. LTD.
    Inventors: Kai Hwa Chew, Meng Kiong Lim, Yong Ling Wu, Hui Huang
  • METHODS OF PURIFYING NANOSTRUCTURES
    Publication number: 20180354039
    Abstract: The present invention relates to methods of purifying nanostructures. The nanostructures may be silver nanowires.
    Type: Application
    Filed: November 11, 2016
    Publication date: December 13, 2018
    Inventors: Kai Hwa CHEW, Meng Kiong LIM, Yong Ling WU, Hui HUANG
  • Solders
    Patent number: 7472817
    Abstract: A substantially lead-free solder, comprising: from around 96.8% to around 99.3% tin; from around 0.2% to around 3.0% copper; and from around 0.02% to around 0.12% silicon.
    Type: Grant
    Filed: February 12, 2007
    Date of Patent: January 6, 2009
    Assignees: Quantum Chemical Technologies (Singapore) Pte. Ltd, Singapore Asahi Chemical & Solder Industries Pte.
    Inventors: Kai Hwa Chew, Vincent Yue Sern Kho
  • Solders
    Patent number: 6843862
    Abstract: A substantially lead-free solder with enhanced properties comprises from 88.5% to 93.5% tin; from 3.5% to 4.5% silver; from 2.0% to 6.0% indium; and from 0.3% to 1.0% copper. The solder may also comprise up to 0.5% of an anti-oxidant or anti-skinning additive. A solder embodying the invention finds particular utility in wave-soldering processes where it may be used as a direct replacement for conventional tin/lead solder.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: January 18, 2005
    Assignees: Quantum Chemical Technologies (Singapore) Pte Ltd, Singapore Asahi Chemical and Solder Industries Pte Ltd
    Inventors: Kai Hwa Chew, Wei Chih Pan
  • Solders
    Publication number: 20020057986
    Abstract: A solder comprising: between 87.2% and 89.5% tin; between 4.0% and 4.8% bismuth; between 3.5% and 4.5% indium; and between 3.0% and 3.5% silver.
    Type: Application
    Filed: August 17, 2001
    Publication date: May 16, 2002
    Applicant: Quantum Chemical Technologies (Singapore) Pte Ltd.
    Inventors: Kai Hwa Chew, Wei Chih Pan