A multipackage system for providing a refinish coating composition and a method for applying the same onto a substrate. The method comprises separately transporting at least one component under pressure to a proportioning device which provides a controlled volumetric ratio of the components. The components of the coating composition are then mixed and coated onto the substrate at ambient temperature or, to accelerate curing, at moderate temperatures. The compositions involve new or modified existing chemistries that have a more limited pot life than conventionally formulated for commercial use.
A kit for forming a multi-component coating formulation for application using a hand-held spraying apparatus to produce a finished coating on a surface comprises a first and a second container holding respective first and second components of a multi-component coating formulation. The kit also includes at least one dispenser in the form a generally tubular body member having a closure at both a first and a second end thereof. The dispenser holds a predetermined volume of a polymerization catalyst solution having "w" weight percent of catalyst therein.The dispenser has a predetermined cross sectional area "a" given by the relationship: a.apprxeq.PA[W/w]10.sup.-6, where "A" is the cross sectional area of the reservoir holding a liquid coating formulation having "W" weight percent of solids; and P is the ratio by weight of the catalyst to the solids desired in the finished coating, in parts per million.
A method for introducing a polymerization catalyst into a coating formulation as the formulation flows from a reservoir includes the steps of: opening the first end of a sealed dispenser holding a predetermined volume of a polymerization catalyst solution and inserting the dispenser into the reservoir such that the open end of the dispenser is positioned near the outlet of the reservoir; with the dispenser so positioned, opening the second end of the dispenser to atmosphere. The head of the liquid coating formulation in the reservoir prevents flow of the catalyst solution from the dispenser until the liquid coating formulation flows from the reservoir into the flow channel. Thus, the catalyst solution mixes with the coating formulation in a way that a predetermined concentration of the catalyst solution is maintained in the coating formulation as the coating formulation flows from the reservoir.
A process for refinishing a motor vehicle by selecting and mixing two or more pigmented base paints from a series of master colors, each base paint having a hydroxyl functional polymer selected from the group consisting of an acrylic addition polymer, a polyester polymer and mixtures thereof, having a number average molecular weight of 600 to 10 000 and a hydroxyl value of 5 to 500, and adding a hardener of a polyisocyanate crosslinker to react and crosslink with said hydroxyl functional polymer in each base paint to form a thermosetting pigmented composition, the improvement in the process comprising; adding a catalyst mixture of a tin catalyst and a polyfunctional thiol having at least three thiol groups per molecule in which the ratio of the number of moles of thiol groups from the polyfunctional thiol to the number of moles of tin from the tin catalyst is 1:1 to 500:1, to form a catalyzed pigmented coating composition having a more constant irrespective of the pigments contained in the two or more basic paints; applying a layer of the catalyzed pigmented coating composition to the surface of the motor vehicle, and; causing the applied layer to dry and cure.
A multi-component proportioning system for dispensing a multi-component coating composition is provided. The delivery system is particularly useful in providing multi-component compositions to a multi-component dispenser. The system provides very accurate mix ratios due to the consistent, reproducible displacement of components from the liquid pump assemblies used in the multi-component proportioning system regardless of viscosity. Such accuracy eliminates improper mixing of components that can lead to reworking and lost time, materials, and profits.
The present invention is directed to a multiple component coating composition comprising (a) a film forming binder component having isocyanate reactive groups; (b) a stable polyisocyanate solution comprising organic liquid and up to 30% by weight, based on the weight of the polyisocyanate solution, of a polyisocyanate having reactive isocyanate groups selected from an aromatic polyisocyanate having tertiary isocyanate groups or a (meth)acrylic polymer containing reactive isocyanate groups; and (c) optionally, a tinting composition comprising pigment, a dispersing agent and an organic liquid carrier; whereby components (a), (b) and (c) are blended together before application to a substrate and after application to a substrate the composition is cured to form a finish. The present invention is also directed to a method of producing a finish on a substrate and to the resulting coated substrate.
