1. A web-guiding system for guiding a web of media travelling from upstream to downstream along a transport path in an in-track direction, the web of media having a first side and an opposing second side, comprising:
a web-guiding structure including an exterior surface having a pattern of recesses formed into the exterior surface, wherein the web of media travels past the web-guiding structure with the first side of the web of media contacting at least some non-recessed portions of the exterior surface of the web-guiding structure;
an air source for providing an air flow between the first side of the web of media and the exterior surface of the web-guiding structure thereby producing a lifting force to lift portions of the web of media overlying the recesses away from the exterior surface of the web-guiding structure; and
wherein the air source is located downstream of the web-guiding structure and blows air between the first side of the web of media and the exterior surface of the web-guiding structure along a boundary where the web of media leaves contact with the web-guiding structure.
2. The web-guiding system of claim 1 wherein a direction of travel of the web of media is redirected by at least 2 degrees as it travels along the transport path past the web-guiding structure.
3. The web-guiding system of claim 1 wherein the exterior surface of the web-guiding structure is curved.
4. The web-guiding system of claim 1 wherein the web-guiding structure is a rotating roller.
5. The web-guiding system of claim 4 wherein a diameter of the exterior surface of the roller varies along a length of the roller to provide a convex or a concave surface profile.
6. The web-guiding system of claim 1 wherein the exterior surface of the web-guiding structure is provided by a fixed media support having a surface facing the web of media.
7. The web-guiding system of claim 6 wherein the exterior surface of the fixed media support has an arc-shaped cross-section.
8. The web-guiding system of claim 6 wherein the exterior surface is fabricated using a material having a coefficient of friction with the web of receiver of less than 0.2.
9. The web-guiding system of claim 1 wherein the recesses formed into the exterior surface of the web-guiding structure have rounded edges where they meet the non-recessed portions of the exterior surface of the web-guiding structure.
10. The web-guiding system of claim 1 wherein the recesses include a plurality of grooves that extend along at least a portion of the exterior surface of the web-guiding structure, each of the grooves being parallel to the in-track direction.
11. The web-guiding system of claim 1 wherein the air flow provided between the first side of the web of media and the exterior surface of the web-guiding surface varies as a function of cross-track position along a length of the web-guiding structure.
12. The web-guiding system of claim 11, wherein the air source includes a manifold with openings that are aligned with the recesses to vary the air flow across a cross-track length of the web-guiding structure such that the lifting force is directed to the portions of the web of media overlying the recesses.
13. The web-guiding system of claim 11 wherein the air source includes an adjustable manifold providing an adjustable cross-track air flow profile.
14. The web-guiding system of claim 1 further including an air restrictor positioned on an opposite side of the web-guiding structure from the air source adapted to restrict the air flow which passes between the first side of the web of media and the exterior surface of the web-guiding structure.
15. The web-guiding system of claim 1 wherein the web-guiding system is a component of a printing system adapted to print on one or both sides of the web of media.
16. A web-guiding system for guiding a web of media travelling from upstream to downstream along a transport path in an in-track direction, the web of media having a first side and an opposing second side, comprising:
a web-guiding structure including an exterior surface having a pattern of recesses formed into the exterior surface, wherein the web of media travels past the web-guiding structure with the first side of the web of media contacting at least some non-recessed portions of the exterior surface of the web-guiding structure; and
an air source for providing an air flow between the first side of the web of media and the exterior surface of the web-guiding structure thereby producing a lifting force to lift portions of the web of media overlying the recesses away from the exterior surface of the web-guiding structure;
wherein the air source is located upstream of the web-guiding structure and blows air between the first side of the web of media and the exterior surface of the web-guiding structure along a boundary where the web of media first comes into contact with the web-guiding structure; and
further including a second air source, the second the air source being located downstream of the web-guiding structure and blows air between the first side of the web of media and the exterior surface of the web-guiding structure along a boundary where the web of media leaves contact with the web-guiding structure.
17. The web-guiding system of claim 16 wherein the web-guiding structure is a rotating roller.
18. The web-guiding system of claim 16 wherein the recesses include a plurality of grooves that extend along at least a portion of the exterior surface of the web-guiding structure, each of the grooves being parallel to the in-track direction.
19. The web-guiding system of claim 16 wherein the air flow provided between the first side of the web of media and the exterior surface of the web-guiding surface varies as a function of cross-track position along a length of the web-guiding structure.
20. A web-guiding system for guiding a web of media travelling from upstream to downstream along a transport path in an in-track direction, the web of media having a first side and an opposing second side, comprising:
a web-guiding structure including an exterior surface having a pattern of recesses formed into the exterior surface, wherein the web of media travels past the web-guiding structure with the first side of the web of media contacting at least some non-recessed portions of the exterior surface of the web-guiding structure;
an air source for providing an air flow between the first side of the web of media and the exterior surface of the web-guiding structure thereby producing a lifting force to lift portions of the web of media overlying the recesses away from the exterior surface of the web-guiding structure; and
an air restrictor positioned on an opposite side of the web-guiding structure from the air source adapted to restrict the air flow which passes between the first side of the web of media and the exterior surface of the web-guiding structure, wherein the air restrictor includes fingers or rollers that are positioned in the recesses between the first side of the receiver media and the exterior surface of the web-guiding structure.
21. The web-guiding system of claim 20 wherein the air source is located upstream of the web-guiding structure and blows air between the first side of the web of media and the exterior surface of the web-guiding structure along a boundary where the web of media first comes into contact with the web-guiding structure.
22. The web-guiding system of claim 20 wherein the web-guiding structure is a rotating roller.
23. The web-guiding system of claim 20 wherein the air flow provided between the first side of the web of media and the exterior surface of the web-guiding surface varies as a function of cross-track position along a length of the web-guiding structure.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-16. (canceled)
17. A process for producing an elastomeric polymer particles in a gas phase polymerization reaction, said process comprising:
a) introducing one or more polymerizable monomers, comprising one or more conjugated or nonconjugated diene monomers having from 4 to 20 carbons, into a reactor, operating under gas phase polymerization conditions, at a temperature of at least 50\xb0 C.;
b) introducing into said reactor a flow aid material that is capable of preventing substantial formation of polymer particle agglomerates, and wherein the flow aid is a solid particulate;
c) introducing into said reactor a polymerization catalyst mixture, comprising a group 4 metal complex containing at least one cyclic ligand, containing delocalized \u03c0-electrons, and corresponding to the formula:
wherein,
M is titanium or zirconium in the +2, +3 or +4 formal oxidation state;
R3, in each occurrence, independently is selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinations thereof, said R3 having up to 20 non-hydrogen atoms, or adjacent R3 groups together form a divalent derivative, thereby forming a fused ring system,
each X is chloride, hydride, or a hydrocarbyl hydrocarbyloxy, or trihydrocarbylsilyl group, or a dihydrocarbylamino-, hydrocarbyleneamino-, hydrocarbyloxy-, or trihydrocarbylsilyl-substituted derivative thereof, said group or substituted group having up to 30 non-hydrogen atoms, or two X groups together form a neutral C4-60 conjugated diene or a divalent derivative thereof;
x is 1 or 2 selected to provide charge balance;
Y is \u2014O\u2014, \u2014S\u2014, \u2014NR*\u2014, \u2014PR*\u2014;
Z is SiR*2, CR*2, SiR*2SiR*2, CR*2CR*2, CR*\u2550CR*, CR*2SiR*2, SnR*2, or GeR*2, wherein R* is hydrogen, or C1-10 hydrocarbyl;
and a cocatalyst therefor into said reactor;
and wherein said steps a), b) and c) occur in any order, two together, or all three simultaneously; and
d) withdrawing a polymer product from the reactor in the form of free flowing polymer particles.
18. The process of claim 17, wherein the metal complex corresponds to the formula:
wherein R3, in each occurrence, independently is selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinations thereof, said R3 having up to 20 non-hydrogen atoms, or adjacent R3 groups together form a divalent derivative thereby forming a fused ring system;
each X is chloride, hydride or a hydrocarbyl, hydrocarbyloxy, or trihydrocarbylsilyl group, or a dihydrocarbylamino-, hydrocarbyleneamino-, hydrocarbyloxy-, or trihydrocarbylsilyl-substituted derivative thereof, said group or substituted group having up to 30 non-hydrogen atoms, or two X groups together form a neutral C4-60 conjugated diene or a divalent derivative thereof;
x is 1 or 2, selected to provide charge balance;
Y is \u2014O\u2014, \u2014S\u2014, \u2014NR*\u2014, \u2014PR*\u2014;
Z is SiR*2, CR*2, SiR*2SiR*2, CR*2CR*2, CR*\u2550CR*, CR*2SiR*2, SnR*2, or GeR*2, wherein R* is hydrogen, or C1-10 hydrocarbyl; and
R\u2033 is a divalent hydrocarbylene- or substituted hydrocarbylene group forming a fused system, with the remainder of the metal complex, said R\u2033 containing from 1 to 30 nonhydrogen atoms.
19. The process claim 17, wherein a hindered phenol is introduced into the reactor.
20. The process claim 19, wherein a hindered phenol is introduced into the reactor in step c), along with the polymerization catalyst.
21. The process of claim 19, wherein the hindered phenol is 2,6-ditertiarybutylphenol.
22. The process of claim 17, wherein one or more conjugated or non-conjugated diene monomers having from 4 to 20 carbon atoms, ethylene, and one or more C3-8 \u03b1-olefins are polymerized into an elastomeric polymer.
23. The process of claim 17, wherein the polymer has a Mooney viscosity of at least 100.
24. The process of claim 19, wherein the polymer has a Mooney viscosity of at least 100.
25. The process of claim 17, wherein the polymer has a crystallinity less than 1.5 percent.
26. The process of claim 17, wherein the flow aid is selected from carbon black, clay and silicon treated derivatives thereof.
27. The process of claim 25, wherein the flow aid is carbon black.
28. The process of claim 19, wherein the flow aid is selected from carbon black, clay, or silicon treated derivatives thereof.
29. The process of claim 28, wherein the flow aid is carbon black.
30. The process of claim 17, wherein the catalyst and cocatalyst composition is supplied to the reaction zone of the reactor in the form of a liquid.
31. The process of claim 17, wherein the reactor is a gas phase, fluidized bed reactor.
32. The process of claim 19, wherein the reactor is a gas phase, fluidized bed reactor.
33. The process of claim 17, wherein one or more conjugated or non-conjugated diene monomers having from 4 to 20 carbon atoms is polymerized in a conversion efficiency greater than 90 percent.
34. The process of claim 19, wherein one or more conjugated or non-conjugated diene monomers having from 4 to 20 carbon atoms is polymerized in a conversion efficiency greater than 90 percent.
35. The process of claim 17, wherein the group 4 metal complex corresponds to the formula:
and wherein R3, X, Y, Z and x are as previously defined in claim 1.
36. The process of claim 17, wherein the catalyst composition comprises ethylbenzene.