Aqueous Coatings typically provide less than adequate open and wet edge time to repair irregularities in a still-wet coating after being applied to a substrate. Aqueous coatings generally employ dispersed high molecular weight polymers as the binder material in the coating. The use of such polymers results in short wet edge times when the coating composition is dried because the dispersed polymer particles tend to coalesce in the edge region of an applied coating relatively soon after the coating has been applied. As a continuous film is formed, the viscosity of the coating increases rapidly, due to the high molecular weight of the polymers comprising the coatings, which leads to limited wet edge and open times. Accordingly, there is a need for additives that can prolong wet edge and open times without contributing significandy to the VOC content of the coating and without compromising other coating performance properties.
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