Patents by Inventor Ronald Ligthart

Ronald Ligthart 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: 9567434
    Abstract: A process for preparation of a polyamide PA-4X containing monomer units of 1,4-diaminobutane and an aliphatic linear dicarboxylic acid X with at least 8 carbon atoms, which contains the following steps: 1) making a solution comprising a salt of 1,4-diaminobutane and the aliphatic linear dicarboxylic acid and water, at a temperature at which the salt dissolves; 2) concentrating the solution of the salt at a temperature above the crystallization temperature of the salt, at a pressure of at most 7 barA to a water content of between 0 and 30 wt % based on the total amount of solution, 3) producing a polymer from the solution obtained by step 2, while keeping the polymer in a melt and at a pressure of less than 18 barA, 4) depressurizing the polymer obtained at step 3 while keeping the polymer in the melt to further polymerize the polymer. In an preferred embodiment the aliphatic linear dicarboxylic acid is 1,10-decanedioic acid.
    Type: Grant
    Filed: May 5, 2011
    Date of Patent: February 14, 2017
    Assignee: DSM IP ASSETS B.V.
    Inventors: Pim Gerard Anton Janssen, Ronald Ligthart
  • Patent number: 8822631
    Abstract: A process for the production of a polymer containing monomer units of butane-1,4-diamine and 1,10-decanedioic acid (PA-410) having a viscosity number (VN) of at least 105 ml/gram includes making a solution of a salt of butane-1,4-diamine and 1,10-decanedioic acid in water, concentrating the solution of the salt at a temperature of between 100 and 180° C. and a pressure of between 1.0 and 3.0 bar to a water content of between 4 and 8 wt %, producing a prepolymer from the salt containing monomer units of butane-1,4-diamine and 1,10-decanedioic acid at a temperature of between 185 and 205° C., and thereafter subjecting the prepolymer to post condensation.
    Type: Grant
    Filed: May 5, 2011
    Date of Patent: September 2, 2014
    Assignee: DSM IP Assets B.V.
    Inventors: Pim Gerard Anton Janssen, Ronald Ligthart
  • Publication number: 20130274399
    Abstract: Heat stabilized polyamide composition, characterized in that the composition contains polyamide 410 (PA-410) and a copper compound and reinforcement fibers. PA-410 is a polyamide containing monomer units derived from a dicarboxylic acid with a chain of 10 carbon atoms between the carboxylic acid groups and a diamine with 4 carbon atoms. Preferably as the dicarboxylic acid 1,10 decandioic acid is used. As the diamine preferably 1,4-butanediane is used.
    Type: Application
    Filed: October 17, 2011
    Publication date: October 17, 2013
    Applicant: DSM IP ASSETS B.V.
    Inventors: Ronald Ligthart, Pieter Gijsman
  • Publication number: 20130211039
    Abstract: A process for the production of a polymer containing monomer units of butane-1,4-diamine and 1,10-decanedioic acid (PA-410) comprising the steps of: 1) making a solution of a salt of butane-1,4-diamine and 1,10-decanedioic acid in water, 2) concentrating the solution of the salt at a temperature of between 100 and 180° C. and a pressure of between 1.0 and 3.0 bar to a water content of between 4 and 8 wt %, 3) producing from the salt a prepolymer containing monomer units of butane-1,4-diamine and 1,10-decanedioic acid at a temperature of between 185 and 205° C. and 4) post condensation of the prepolymer. Also claimed is PA-410 having a viscosity number (VN) of at least 100 ml/gram.
    Type: Application
    Filed: May 5, 2011
    Publication date: August 15, 2013
    Applicant: DSM IP ASSETS B.V.
    Inventors: Pim Gerard Anton Janssen, Ronald Ligthart
  • Publication number: 20130137815
    Abstract: Injection molded polymeric part produced from a polymer composition comprising polyamide 410 (PA-410) and less than 1.5 weight % of a mold release agent. In a preferred embodiment the polymer composition contains less than 1 wt. % of a mold release agent.
    Type: Application
    Filed: April 14, 2011
    Publication date: May 30, 2013
    Applicant: DSM IP ASSETS B.V.
    Inventors: Eric Willem Van Der Vegte, Ronald Ligthart
  • Publication number: 20130131307
    Abstract: A process for preparation of a polyamide PA-4X containing monomer units of 1,4-diaminobutane and an aliphatic linear dicarboxylic acid X with at least 8 carbon atoms, which contains the following steps: 1) making a solution comprising a salt of 1,4-diaminobutane and the aliphatic linear dicarboxylic acid and water, at a temperature at which the salt dissolves; 2) concentrating the solution of the salt at a temperature above the crystallization temperature of the salt, at a pressure of at most 7 barA to a water content of between 0 and 30 wt % based on the total amount of solution, 3) producing a polymer from the solution obtained by step 2, while keeping the polymer in a melt and at a pressure of less than 18 barA, 4) depressurizing the polymer obtained at step 3 while keeping the polymer in the melt to further polymerize the polymer. In an preferred embodiment the aliphatic linear dicarboxylic acid is 1,10-decanedioic acid.
    Type: Application
    Filed: May 5, 2011
    Publication date: May 23, 2013
    Applicant: DSM IP ASSETS B.V.
    Inventors: Pim Gerard Anton Janssen, Ronald Ligthart