Patents by Inventor Alfons Wolf

Alfons Wolf 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: 5670572
    Abstract: The present invention relates to melamine-formaldehyde resins comprising a guanamine, to processes for their preparation and to their use for the production of melamine resin films and edgings.
    Type: Grant
    Filed: November 3, 1995
    Date of Patent: September 23, 1997
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Jurgen Ott, Manfred Schon, Wilhelm Adam, Frank Scholl, Alfons Wolf
  • Patent number: 4430494
    Abstract: Modified melamine-formaldehyde resins having a melamine:formaldehyde molar ratio of 1:(1.27 to 0.7) are prepared by heating melamine in an aqueous solution or suspension with formaldehyde in a melamine:formaldehyde molar ratio of 1:(1.27 to 0.7) at a pH value of 8 to 11 and at temperatures of 105.degree. to 160.degree. C. until the finished resin has reached a dilutability with water of 1:(0.1 to 4) at 20.degree. C., and, before, during or after the condensation reaction, adding less than 25% by weight of a glycol ether of the formulaR(OCH.sub.2 CH.sub.2).sub.n OHin which R denotes alkyl having 1 to 4 C atoms and n denotes an integer from 1 to 5, and/or of p-toluenesulfonamide. The resins are used in particular for the production of molding compositions.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: February 7, 1984
    Assignee: Cassella Aktiengesellschaft
    Inventors: Hans Honel, Walter Michel, Steffen Piesch, Karin Schluter, Alfons Wolf
  • Patent number: 4328326
    Abstract: Partially etherified melamine-formaldehyde resins having a melamine:formaldehyde molar ratio of 1:(1.25 to 1) can be prepared by a condensation reaction under neutral or weakly alkaline conditions if the condensation reaction is carried out in the presence of a glycol monoether of the general formula IR(OCH.sub.2 CH.sub.2).sub.n OH (I)wherein R denotes alkyl having 1 to 4 C atoms and n denotes a number from 1 to 5. The partially etherified melamine-formaldehyde resins are suitable for the production of compression moulding compositions having a high flow and minimal processing shrinkage and after-shrinkage.
    Type: Grant
    Filed: January 9, 1981
    Date of Patent: May 4, 1982
    Assignee: Cassella Aktiengesellschaft
    Inventors: Steffen Piesch, Alfons Wolf
  • Patent number: 4303561
    Abstract: Partially etherified melamine-formaldehyde resins having a melamine: formaldehyde molar ratio of 1:(1.25 to 1) can be prepared by a condensation reaction under neutral or weakly alkaline conditions if the condensation reaction is carried out in the presence of a glycol monoether of the general formula IR (OCH.sub.2 CH.sub.2).sub.n OH (I)wherein R denotes alkyl having 1 to 4 C atoms and n denotes a number from 1 to 5. The partially etherified melamine-formaldehyde resins are suitable for the production of compression moulding compositions having a high flow and minimal processing shrinkage and after-shrinkage.
    Type: Grant
    Filed: May 29, 1979
    Date of Patent: December 1, 1981
    Assignee: Cassella Aktiengesellschaft
    Inventors: Steffen Piesch, Alfons Wolf
  • Patent number: 4250282
    Abstract: A melamine-formaldehyde resin useful for making coated wood-based materials and laminates and having a prolonged pot life comprises (a) melamine-formaldehyde precondensation product wherein the molar ratio of melamine:formaldehyde is 1:1.4 to 1:2.6 and (b) 0.1 to 1.0% by weight based on total solids, of an amine of the formula ##STR1## wherein R.sup.1 and R.sup.2 are each identical or different alkyl having 1 to 4 carbon atoms and R.sup.3 is 2-hydroxyethyl, 2-(2-hydroxyethoxy)-ethyl, 3-hydroxy-1-propyl, 3-hydroxy-2-propyl, 2,3-dihydroxypropyl or--CH.sub.2 CH.sub.2 --NR.sup.1 R.sup.2,wherein said amine may be present entirely or partially in the form of its reaction product with the melamine-formaldehyde pre-condensation product.
    Type: Grant
    Filed: November 13, 1979
    Date of Patent: February 10, 1981
    Assignee: Cassella Aktiengesellschaft
    Inventors: Peter Dorries, Steffen Piesch, Alfons Wolf
  • Patent number: RE31366
    Abstract: A melamine-formaldehyde resin useful for making coated wood-based materials and laminates and having a prolonged pot life comprises (a) melamine-formaldehyde precondensation product wherein the molar ratio of melamine:formaldehyde is 1:1.4 to 1:2.6 (b) 0.1 to 1.0% by weight based on total solids, of an amine of the formula ##STR1## wherein R.sup.1 and R.sup.2 are each identical or different alkyl having 1 to 4 carbon atoms and R.sup.3 is 2-hydroxyethyl, 2-(2-hydroxyethoxy)-ethyl, 3-hydroxy-1-propyl, 3-hydroxy-2-propyl, 2,3-dihydroxypropyl or--CH.sub.2 CH.sub.2 --NR.sup.1 R.sup.2,wherein said amine may be present entirely or partially in the form of its reaction product with the melamine-formaldehyde pre-condensation product.
    Type: Grant
    Filed: January 11, 1982
    Date of Patent: August 30, 1983
    Assignee: Cassella Aktiengesellschaft
    Inventors: Peter Dorries, Steffen Piesch, Alfons Wolf