1. A syringe comprising:
a barrel having a fluid chamber, an inside surface, a proximal end, a distal end and a tip extending from the distal end having a passageway in fluid communication with the chamber; and
a plunger rod adapted to slidingly engage the inside surface of the fluid chamber, the plunger rod including a proximal portion having a first braking surface, a distal portion having a second braking surface, and a connector joining the proximal portion and the distal portion adapted to break upon application of a breaking force to the plunger rod, wherein the second braking surface slidingly engages with the first braking surface to create a motion-resistive force between the proximal portion and the distal portion upon breaking of the connector.
2. The syringe of claim 1, wherein the first braking surface is sloped with respect to a longitudinal centerline of the plunger rod.
3. The syringe of claim 2, wherein the second braking surface is sloped with respect to a longitudinal centerline of the plunger rod.
4. The syringe of claim 3, wherein a first distance along a longitudinal centerline of the plunger rod separating a most distal portion of the breakable connection from the distal portion exceeds a second distance separating a most distal portion of the first braking surface from a most proximal portion of the second braking surface.
5. The syringe of claim 1 wherein the first braking surface is disposed along a distal region of the proximal portion, and the second braking surface is disposed along a proximal region of the distal portion.
6. The syringe of claim 1, wherein the first braking surface or the second braking surface is disposed adjacent to the connector.
7. The syringe of claim 4, wherein the first braking surface or the second braking surface is disposed adjacent to the connector.
8. A syringe comprising:
a barrel having a fluid chamber, an interior surface, a proximal end, a distal end and a tip at the distal end including a fluid passageway therethrough; and
a plunger rod including a proximal portion having a proximal end with a flange adapted to accept a force applied from a user along a longitudinal centerline of the plunger rod; a distal portion having a distal end with a stopper adapted to provide a fluid tight slidable seal with the interior surface; a breakable member connecting the proximal portion to the distal portion adapted to break when the force applied by the user exceeds a breaking force; and an elastic element disposed within a gap separating the proximal portion from the distal portion along the longitudinal centerline.
9. The syringe of claim 8 wherein the elastic element is disposed adjacent to the breakable member.
10. The syringe of claim 8, wherein the elastic element includes a spring.
11. A syringe comprising:
a barrel including an interior surface, a proximal end, a distal end, a fluid chamber and a tip at the distal end including an opening to allow fluid to pass therethrough;
a plunger rod including a proximal portion having a proximal end with a flange adapted to accept a force applied from a user along a longitudinal centerline of the plunger rod; a distal portion having a distal end with a stopper adapted to provide a slidable seal with the interior surface of the barrel; a breakable connection between the proximal portion and the distal portion adapted to break when the force applied by the user exceeds a breaking force; and
an impulse reduction means disposed on the plunger rod between the stopper and the flange for reducing a contact impulse between the proximal portion and the distal portion generated when the proximal portion strikes the distal portion in response to the breakable connection breaking.
12. The syringe of claim 11 wherein the impulse reduction means comprises:
a first braking surface disposed on the proximal portion; and
a second braking surface disposed on the distal portion, the second braking surface adapted to slidingly engage with the first braking surface to create a motion-resistive force between the proximal portion and the distal portion.
13. The syringe of claim 12 wherein the first braking surface is sloped with respect to the longitudinal centerline of the plunger rod.
14. The plunger rod of claim 12 wherein the second braking surface is sloped with respect to the longitudinal centerline of the plunger rod.
15. The syringe of claim 13 wherein a first distance along the longitudinal centerline of the plunger rod separating a most distal portion of the breakable connection from the distal portion exceeds a second distance separating a most distal portion of the first braking surface from a most proximal portion of the second braking surface.
16. The syringe of claim 12 wherein the first braking surface is disposed along a distal region of the proximal portion, and the second braking surface is disposed along a proximal region of the distal portion.
17. The syringe of claim 15 wherein the first braking surface or the second braking surface is disposed adjacent to the breakable connection.
18. The syringe of claim 11 wherein the impulse reduction means comprises an elastic element disposed within a gap along the longitudinal centerline that separates the proximal portion from the distal portion.
19. The syringe of claim 17 wherein the elastic element is disposed adjacent to the breakable connection.
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 process for the production of a biaxially oriented polypropylene film wherein the film comprises at least one layer, which comprises heating and melting propylene polymer B in a first extruder and shaping and extruding the molten mass of the propylene polymer B through a flat sheet die and taking off the melt exiting the flat sheet die on one or more rolls and solidifing to give a precursor and streching the precursor in the longitudinal and transverse direction, wherein
A. a propylene polymer A without a fraction of recycled material is heated and melted in a second extruder, and
B. the molten mass of the propylene polymer A is fed to two sides of the propylene polymer molten mass B in such a way that all of the molten masses are extruded together and simultaneously through the flat sheet die, and the propylene polymer A without a fraction of recycled material forms border regions of the film during the production process, and
C. two border regions comprising the propylene polymer A are cut off after longitudinal and transverse stretching of the film, and
D. this film cut off from the two border regions is melted and mixed together with the polypropylene polymer B and extruded to form the precursor film in the first extruder, wherein the process comprises no material that has passed through the process more than once.
2. The process as recited in claim 1, wherein the propylene polymer B and the propylene polymer A are the same polymer.
3. The process as recited in claim 1, wherein the propylene polymer A is extruded a first time as an edge strip and a second time together with the polymer B as the film.
4. The process as recited in claim 1, wherein the propylene polymer A is melted, extruded and cooled during regranulation of an edge strip material.
5. The process as recited in claim 1, wherein the proportion of recycled polymer A in the mixture of polymer B and recycled polymer A is 0.5 to 40% by weight.
6. The process as recited in claim 1, wherein a stabilizer or neutralizing agent or both a stabilzer and a neutralizing agent are added to the propylene polymer B and the propylene polymer A.
7. The process as recited in claim 1, wherein the residual ash content of the propylene polymer A is <70 ppm and the chlorine content is <50 ppm.
8. The process as recited in claim 1, wherein the propylene polymer A is a mixture of various propylene polymers with no recycled material content.
9. The process as recited in claim 1, wherein the propylene polymer B is a mixture of various propylene polymers.
10. The process as recited in claim 1, wherein the propylene polymers A and B are different polymers and the melting points of the propylene polymers A and B differ from one another by not more than 15\xb0 C.
11. The process as recited in claim 1, wherein the polypropylene film comprises a further layer.
12. The process as recited in claim 1, wherein the film includes multiple layers and the layer containing propylene polymers A and B forms a base layer of the multilayer film.
13. The process as recited in claim 1, wherein the film, has one or more cover layer(s) on one or both sides, which contain 98-100% by weight propylene polymer B.
14. The process as recited in claim 1, wherein the film has a separated border area which consists of 99-100% by weight propylene polymer A.