1. A process for the preparation of NCO-terminated prepolymers which are clear and storage-stable at room temperature, comprising
(A) reacting
(1) one or more polycarbonate polyols, with
(2) a stoichiometric excess of 4,4\u2032-diphenylmethane diisocyanate, wherein (1) the polycarbonate polyol is treated by a short-path or thin-film distillation before being being reacted with the 4,4-diphenylmethane diisocyanate, such that the hydroxyl value of the polycarbonate polyol is reduced by at least 1.5 hydroxyl value units.
2. In a process for the preparation of polyurethanes comprising reacting (I) at least one polyisocyanate component with (II) at least one isocyanate-reactive component, the improvement wherein (I) said polyisocyanate component comprises the NCO-terminated prepolymer produced by the process of claim 1.
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. An apparatus, comprising:
a magnetic head, the magnetic head having:
a first portion and a second portion, the first portion and the second portion together providing a tape bearing surface,
wherein the first portion has an opening at least partially encircling the second portion,
the second portion having at least one array of transducers,
wherein a longitudinal axis of each of the at least one array is defined between opposite ends thereof,
wherein the longitudinal axis of each of the at least one array of transducers is oriented at an angle relative to a line oriented orthogonally to an intended direction of tape travel thereacross, the angle being between 0.2\xb0 and about 10\xb0,
wherein the second portion has a first edge oriented at a second angle between 0.2\xb0 and about 10\xb0 relative to the line, and a second edge opposite the first edge, the second edge being oriented at a third angle between 0.2\xb0 and about 10\xb0 relative to the line.
2. An apparatus as recited in claim 1, wherein the tape bearing surface has a generally arcuate cross sectional profile.
3. An apparatus as recited in claim 1, wherein the first and second edges are oriented about parallel to the at least one array of transducers.
4. An apparatus as recited in claim 1, wherein the opening of the first portion has an edge facing the second portion, the edge extending along a second angle between 0.2\xb0 and about 10\xb0.
5. An apparatus as recited in claim 1, wherein the second portion has a second one of the arrays of transducers, wherein the longitudinal axes of the arrays are oriented about parallel to each other, wherein a first of the arrays is offset from the second of the arrays in a direction parallel to the longitudinal axes of the arrays such that at least some of the transducers of the first array are about aligned with at least some of the transducers of the second array in an intended direction of tape travel thereacross.
6. An apparatus as recited in claim 1, comprising:
a mechanism for orienting the second portion to control a transducer pitch presented to a tape.
7. An apparatus as recited in claim 6, wherein the first and second portions are selectively positionable for compensating for tape skew, wherein the second portion is selectively positionable in a direction orthogonal to the intended direction of tape travel for track following.
8. An apparatus as recited in claim 6, wherein the first and second portions are selectively positionable for compensating for tape skew and for track following.
9. An apparatus as recited in claim 8, wherein the second portion is independently positionable relative to the first portion.
10. An apparatus as recited in claim 6, wherein the first portion is fixed in the apparatus thereby preventing movement thereof relative to the apparatus, wherein the second portion is selectively positionable for compensating for tape skew and for track following.
11. An apparatus as recited in claim 6, wherein the first portion is coupled to a coarse actuator, wherein the first portion is not tiltable relative to the line oriented orthogonally to the intended direction of tape travel, wherein the second portion is selectively positionable for compensating for tape skew and for track following.
12. An apparatus as recited in claim 6, comprising a controller configured to control the mechanism for orienting the at least one array of transducers based on a state of expansion of the tape determined by the apparatus.
13. An apparatus as recited in claim 6, comprising a controller configured to control the mechanism for orienting the at least one array of transducers based on skew of the tape.
14. An apparatus as recited in claim 1, wherein the first portion and the second portion are fixed relative to each other.
15. An apparatus as recited in claim 1, wherein the second portion is selectively positionable relative to the first portion.
16. An apparatus as recited in claim 1, comprising:
a drive mechanism for passing a magnetic medium over the magnetic head; and
a controller electrically coupled to the magnetic head.
17. An apparatus, comprising:
a magnetic head, the magnetic head having:
a first portion and a second portion, the first portion and the second portion together providing a tape bearing surface,
wherein the first portion has an opening at least partially encircling the second portion,
the second portion having at least one array of transducers,
wherein a longitudinal axis of each of the at least one array is defined between opposite ends thereof,
wherein the longitudinal axis of each of the at least one array of transducers is oriented at an angle relative to a line oriented orthogonally to an intended direction of tape travel thereacross, the angle being between 0.2\xb0 and about 10\xb0,
wherein the opening of the first portion has an edge facing the second portion, the edge extending along a second angle between 0.2\xb0 and about 10\xb0.
18. An apparatus as recited in claim 17, wherein the tape bearing surface has a generally arcuate cross sectional profile.
19. An apparatus as recited in claim 17, wherein the second portion has a second one of the arrays of transducers, wherein the longitudinal axes of the arrays are oriented about parallel to each other, wherein a first of the arrays is offset from the second of the arrays in a direction parallel to the longitudinal axes of the arrays such that at least some of the transducers of the first array are about aligned with at least some of the transducers of the second array in an intended direction of tape travel thereacross.
20. An apparatus as recited in claim 17, comprising:
a mechanism for orienting the second portion to control a transducer pitch presented to a tape.