Stable aqueous dispersions of hydrophilic phenolic resins having low xylenol and bisphenol-A content
申请人:Boyer C. Peter
公开号:US20060229415A1
公开(公告)日:2006-10-12
Storage stable aqueous dispersions of a heat-reactive hydrophilic phenolic resin (e.g., phenol/formaldehyde) are disclosed. The dispersions comprise a base resin that is the reaction product of an aromatic alcohol and an aldehyde, and an etherified resin component selected from the group consisting of an etherified phenol/aldehyde resin, an etherified cresol/aldehyde resin, and mixtures thereof. The dispersions further comprise a protective colloid (e.g., polyvinyl alcohol). The addition of the etherified resin component in an amount of at least about 20% by weight of the base resin provides storage stability, but does not adversely affect the desirable physical and chemical characteristics (e.g., chemical resistance) of end products made from such dispersions. Moreover, the dispersions of the present invention can avoid the use of etherified resin components derived from bisphenol-A and/or xylenols, which present heath concerns in food coating applications.
本发明公开了一种热反应亲水性酚醛树脂(如酚/甲醛)的贮存稳定的水分散体。该分散体包括芳香醇和醛的反应产物基树脂,以及选自醚化苯酚/醛树脂、醚化甲酚/醛树脂及其混合物的醚化树脂组分。分散体还包括保护胶体(如聚乙烯醇)。醚化树脂成分的添加量至少为基础树脂重量的约 20%,可提供贮存稳定性,但不会对由此类分散体制成的最终产品的理想物理和化学特性(如耐化学性)产生不利影响。此外,本发明的分散体可以避免使用从双酚 A 和/或二甲苯醇中提取的醚化树脂成分,这些成分在食品涂料应用中会引起健康问题。