1. A wood protection paint comprising a copolymer emulsion prepared by an emulsion polymerization process comprising:
(a) polymerizing, in a first stage and under ethylene pressure, a first monomer composition comprising from 60 weight percent to 95 weight percent of at least one vinyl ester, and from 5 weight percent to 40 weight percent ethylene to produce a first stage product having a glass transition temperature Tg of less than 25\xb0 C.; and
(b) polymerizing, in a second stage and in the presence of said first stage product, a second monomer composition such that the polymer produced by said second monomer composition has a glass transition temperature Tg of at least 95\xb0 C.
2. A wood protection paint according to claim 1, wherein the vinyl ester is vinyl acetate.
3. A wood protection paint according to claim 1, wherein the copolymer produced by said first monomer composition has a glass transition temperature Tg in the range of 5\xb0 C. to 15\xb0 C.
4. A wood protection paint according to claim 1, wherein the first monomer composition further comprises from 0.05 weight percent to 5 weight percent of at least one of an ethylenically unsaturated mono- andor dicarboxylic acid, an ethylenically unsaturated sulfonic acid, an ethylenically unsaturated phosphoric acid, an ethylenically unsaturated phosphonic acid, and an amide of an ethylenically unsaturated mono- andor dicarboxylic acid.
5. A wood protection paint according to claim 1, wherein the polymer produced by said second monomer composition has a glass transition temperature Tg from 95 to 170\xb0 C., preferably from 95\xb0 C. to 160\xb0 C., more preferably from 95\xb0 C. to 150\xb0 C.
6. A wood protection paint according to claim 1, wherein the second monomer composition comprises at least 90 weight percent of a meth(acrylic) ester or a mixture of at least two different (meth)acrylic esters selected
7. A wood protection paint according to claim 1, wherein the second monomer composition comprises at least 90 weight percent of methyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate or a mixture thereof.
8. A wood protection paint according to claim 1, wherein the second monomer composition comprises at least 90 weight percent of a mixture of methyl methacrylate with an acrylic ester selected from the group consisting of butyl acrylate and ethylhexyl acrylate.
9. A wood protection paint according to claim 1, wherein the second monomer composition further comprises from 0.05 weight percent to 5 weight percent of at least one of an ethylenically unsaturated mono- andor dicarboxylic acid, an ethylenically unsaturated sulfonic acid, an ethylenically unsaturated phosphoric acid, an ethylenically unsaturated phosphonic acid, and an amide of an ethylenically unsaturated mono- andor dicarboxylic acid.
10. A wood protection paint according to claim 1, wherein the weight ratio of the first monomer composition to the second monomer composition is in the range 60:40 to 95:5.
11. A wood protection paint according to claim 1, wherein each of the first and second monomer compositions additionally comprises an anionic emulsifier.
12. A wood protection paint according to claim 1, wherein each of the first and second monomer compositions additionally comprises a nonionic emulsifier.
13. A wood protection paint according to claim 1 and further comprising at least one pigment.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A high energy, high repetition rate workpiece surface heating mechanism comprising:
a pulsed XeF laser operating at or above 4000 Hz and producing a laser output light pulse beam at a center wavelength of about 351 nm;
an optical system narrowing the laser output light pulse beam to less than 20 \u03bcm in a short axis of the laser output light pulse beam and expanding the laser output light pulse beam to form in a long axis of the beam a workpiece covering extent of the long axis;
the optical system including a field stop intermediate the laser and the workpiece;
the workpiece comprising a layer to be heated;
wherein the optical system focuses the laser output light pulse beam at a field stop with a magnification sufficient to maintain an intensity profile that has sufficiently steep sidewalls to allow the field stop to maintain a sufficiently steep beam profile at the workpiece without blocking the beam profile at too high an intensity level.
2. The apparatus of claim 1 further comprising:
a high average power in the laser output light pulse beam as delivered to the workpiece.
3. The apparatus of claim 1 further comprising:
a linebow correction mechanism in a short axis optical assembly.
4. The apparatus of claim 1 further comprising:
the linebow correction mechanism comprises a plurality of weak cross cylinders.
5. The apparatus of claim 1 further comprising:
the optical system comprises a catadioptric projection system.
6. The apparatus of claim 1 further comprising:
wherein the linewidth due to laser diffraction and divergence is less than geometric limitations.
7. The apparatus of claim 1 further comprising:
the system projects adjacent peaks of the nominal XeF spectrum to improve overall depth of focus through the separate center wavelengths of each respective adjacent peak having a different focal plane at the workpiece.
8. The apparatus of claim 1 further comprising:
a linebow is correction mechanism within a field stop optical assembly correcting linebow at the field stop plane and within a workpiece projection optical assembly correcting linebow at the workpiece plane.