Dry film lubricant
The present invention relates to compositions and methods employing a first copolymer that is an acrylic copolymer or styrene/acrylic copolymer having a weight average molecular weight (Mw) of about 8,000 to about 14,000; a second copolymer that is an acrylic copolymer having a Mw of about 90,000 to about 130,000; a wax emulsion or dispersion, and a particulate additive. Optionally, the composition further comprises at least one of a rheological additive, ammonium hydroxide or a defoaming compound.
1 . A composition, comprising:
a first copolymer that is an acrylic copolymer or styrene/acrylic copolymer having a weight average molecular weight (Mw) of about 8,000 to about 14,000;
a second copolymer that is an acrylic copolymer having a Mw of about 90,000 to about 130,000;
water;
a wax emulsion and/or wax dispersion; and
a particulate additive.
2 . The composition of claim 1 , wherein said first copolymer is present in a range from about 10 to about 23 percent by weight of the composition.
3 . The composition of claim 1 , wherein said second copolymer is present in a range from about 30 to about 70 percent by weight of the composition.
4 . The composition of claim 1 , wherein said water is present in a range from about 5 to about 30 percent by weight of the composition.
5 . The composition of claim 1 additionally comprising a rheological additive.
6 . The composition of claim 1 , wherein said theological additive is modified urea in N-methyl pyrrolidine and is present in a range from about 0.1 to about 1 percent by weight of the composition.
7 . The composition of claim 1 comprising a wax emulsion that comprises paraffin and polyethylene.
8 . The composition of claim 7 , wherein said wax emulsion is present in a range from about 3 to about 18 percent by weight of the composition.
9 . The composition of claim 1 , wherein said particulate additive is a silicate.
10 . The composition of claim 1 , wherein said particulate additive is a silicate including at least one of Al or Mg.
11 . The composition of claim 1 , wherein said particulate additive is talc.
12 . The composition of claim 11 , wherein said talc is present in a range from about 0.01 to about 4 percent by weight of the composition.
13 . A coating comprising the composition of claim 1 .
14 . A substrate contacted by the composition of claim 1 , wherein the substrate is stainless steel, galvanized steel, hot dipped galvanized steel, electro galvanized steel, galvanneal alloy, alloy steel comprising 55% aluminum, 43.5% zinc, and 1.5% silicon, cold rolled steel, hot rolled steel, or aluminum.
15 . A method for reducing blocking between substrates, comprising contacting said substrates with the composition of claim 1 .
16 . The method of claim 15 wherein the coating is dried using surface temperatures lower than about 200° F., and as low as about 170° F.
17 . A composition, comprising:
a first copolymer that is an acrylic copolymer or styrene/acrylic copolymer having a weight average molecular weight (Mw) of about 8,000 to about 14,000;
a second copolymer that is an acrylic copolymer having a Mw of about 90,000 to about 130,000;
water;
a wax emulsion;
a particulate additive; and
a viscosity builder.
18 . A composition, comprising:
a styrene/acrylic copolymer colloidal dispersion;
a thermoplastic acrylic copolymer colloidal dispersion;
water;
a urea-containing rheological additive;
a wax emulsion;
a silicate including at least one of Mg or Al; and
ammonium hydroxide.
19 . The composition of claim 18 , further comprising a defoaming compound.
20 . The composition of claim 18 , wherein said silicate is talc.