Gypsum board with a fluorine-containing antifungal agent

Abstract

A novel gypsum board having improved antifungal properties is disclosed. The board comprises a gypsum core, front and back paper facings, and a polymeric antifungal agent effective at inhibiting fungal growth. A preferred polymeric antifungal agent is polyDADMAC or polyTMMC. The novel gypsum board further comprises a non-polymeric antifungal agent comprising a fluorine-containing quaternary ammonium compound. Preferred non-polymeric ammonium compounds include Tetra-n-butylammonium fluoride and Tetraethylammonium fluoride. The polymeric antifungal agent can be present in the gypsum core and/or on one or both of the paper facings. The non-polymeric antifungal agent may be encapsulated in a material or ionically associated with the polymeric antifungal agent to allow releases of the non-polymeric antifungal agent over time and/or upon exposure to moisture. Methods for preparing the aforementioned novel gypsum board are also disclosed.

1 . An antifungal gypsum board comprising a polymeric antifungal agent and a non-polymeric antifungal agent comprising a fluorine-containing quaternary ammonium compound. 
   
   
       2 . The antifungal gypsum board comprising a polymeric antifungal agent and a non-polymeric antifungal agent of  claim 1  wherein said fluorine-containing quaternary ammonium compound is selected from the group consisting of Tetra-n-butylammonium fluoride, Tetraethylammonium fluoride, 3-(Trifluoromethyl)phenyltrimethylammonium bromide, 3-(Trifluoromethyl)-phenyltrimethylammonium iodide, 3-(Trifluoromethyl)phenyltrimethyl-ammonium hydroxide, N-fluoro-N′-(chloromethyl)triethylenediamine Bis(tetrafluoroborate), n-Hexadecyltrimethylammonium hexafluorophosphate, n-Hexadecyltrimethylammonium tetrafluoroborate, Tetra-n-butylammonium bifluoride, Tetra-n-butylammonium difluoro-triphenylsilicate, Tetra-n-butylammonium difluorotriphenylstannate, Tetra-n-butylammonium dihydrogentrifluoride, Tetra-n-butyl ammonium hexafluorophosphate, Tetra-n-butylammonium tetrafluoroborate, Tetraethylammonium tetrafluoroborate, Tetraethylammonium hexafluorophosphate, Tetramethylammonium tetrafluoroborate, and Trifluoromethanesulfonic acid tetra-n-butylammonium salt. 
   
   
       3 . The antifungal gypsum board of  claim 2  wherein said polymeric antifungal agent is selected from the group consisting of polyDADMAC, polyTMMC, and quaternized polyvinyl pyridine derivatives. 
   
   
       4 . The antifungal gypsum board of  claim 3  wherein said polymeric antifungal agent is covalently bound by use of an initiator to a component of the gypsum board, and whereby the non-polymeric antifungal agent resists leaching. 
   
   
       5 . The antifungal gypsum board of  claim 4  wherein said polymeric antifungal agent is polyDADMAC. 
   
   
       6 . The antifungal gypsum board of  claim 4  wherein said polymeric antifungal agent is polyDADMAC and wherein said non-polymeric antifungal agent is selected from the group consisting of Tetra-n-butylammonium fluoride, Tetraethylammonium fluoride, N-Fluoro-N′-(chloromethyl)triethylene-diamine bis(tetrafluoroborate), n-Hexadecyltrimethylammonium tetrafluoroborate, Tetra-n-butylammonium tetrafluoroborate, Tetraethylammonium tetrafluoroborate, and Tetramethylammonium tetrafluoroborate. 
   
   
       7 . The antifungal gypsum board of  claim 6  wherein said non-polymeric antifungal agent is Tetra-n-butylammonium fluoride or Tetraethylammonium fluoride. 
   
   
       8 . The antifungal gypsum board of  claim 4 , further comprising cetyl pyridinium chloride (CPC) as an additional antifungal agent. 
   
   
       9 . The antifungal gypsum board of  claim 5 , further comprising cetyl pyridinium chloride (CPC) as an additional antifungal agent. 
   
   
       10 . The antifungal gypsum board of  claim 7 , further comprising cetyl pyridinium chloride (CPC) as an additional antifungal agent. 
   
   
       11 . An improved method for manufacturing an antifungal gypsum board which comprises the steps:
 a. covalently bonding, by use of an initiator and in the presence of a crosslinker, a polymeric antifungal agent to the board or a component thereof,   b. adding a non-polymeric antifungal agent to the board or a component thereof, wherein said non-polymeric antifungal agent is stabilized by the polymeric antifungal gent, and whereby the non-polymeric antifungal agent resists leaching.   
   
   
       12 . The method of  claim 11  further comprising encapsulating or binding the non-polymeric antifungal agent such that the non-polymeric antifungal agent is released over time, or upon exposure to moisture, or both. 
   
   
       13 . The method of  claim 11  wherein the polymeric antifungal agent is polyDADMAC and the non-polymeric antifungal agent is a fluorine-containing quaternary ammonium compound. 
   
   
       14 . The method of  claim 13  wherein the non-polymeric antifungal agent is Tetra-n-butylammonium fluoride or Tetraethylammonium fluoride. 
   
   
       15 . The method of  claim 14  further comprising encapsulating or binding the non-polymeric antifungal agent such that the non-polymeric antifungal agent is released over time, upon exposure to moisture, or both.