US3911069A — Method of manufacturing multilayered articles

Claim 1

Independent Claim 236 words

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

Claim 2

Independent Claim 236 words

A METHOD FOR MANUFACTURING A MULTILAYERED FABRICATED ARTICLE WHICH COMPRISES EXTRUDING AN UNCURED RUBBER OR EXTRUDABLE AND THEN CURABLE RUBBERY POLYMER MATERIAL BY A FIRST EXTRUDER HAVING A COMPRESSION RATIO OF 1.2 TO 3 INTO A VACUUM CHAMBER, REDUCING THE SIZE OF THE EXTRUDED COMPOSITION IN SAID CHAMBER BY COMMINUTING OR SLICING TO A SMALL THICKNESS WITH A CUTTER, FEEDING THE COMMINUTED OR SLICED PIECES TO A SECOND EXTRUDER WHILE MAINTAINING THE PIECES UNDER REDUCED PRESSURE, EXTRUDING THE COMPOSITION BY THE SECOND EXTRUDER AROUND A CORE WHICH HAS BEEN DRIED AND HEATED PRIOR TO SAID SECOND EXTRUSION TO A TEMPERATURE OF AT LEAST 90*C, AND AT LEAST THE SURFACE OF THE CORE BEING KEPT AT A TEMPERATURE NOT LOWER THAN THE TEMPERATURE WHICH IS 90*C LOWER THAN THE CURING TEMPERATURE, AND INTRODUCING THE COVERED AND SHAPED CORE WITHOUT SUBSTANTIALLY BENDING OR CAUSING DEFORMATION OF THE SAME INTO CURING MEANS CONTAINING A HEATING MEDIUM, WHEREIN SAID COVERED CORE IS CONTACTED WITH THE HEATING MEDIUM WHICH ELEVATES THE TEMPERATURE OF THE UNCURED RUBBER OR PLASTIC COMPOSITION, WHEREBY THE UNCURED RUBBER OR PLASTIC LAVER AROUND THE CORE IS HEATED AND CURED AT SUBSTANTIALLY ATMOSPHERIC PRESSURE, SAID FIRST AND SECOND EXTRUDERS BEING PROVIDED SUCH THAT THE SUM OF THE L/D RATIO OF THE FIRST EXTRUDER AND THE L/D RATIO OF THE SECOND EXTRUDER DOES NOT EXCEED 24, AND WITH THE L/D RATIO OF SAID FIRST EXTRUDER BEING AT LEAST 8.

Claim 3

Dependent Claim 31 words

The method of claim 1 wherein at least the surface of the core is kept at a temperature not lower than the temperature which is 60*C. lower than the curing temperature.

Claim 4

Dependent Claim 34 words

The method of claim 1 wherein the rubber or rubbery polymer material extruded from the first extruder is comminuted or sliced in the vacuum chamber to a thickness of about 40 microns or less.

Claim 5

Dependent Claim 20 words

The method of claim 1 wherein the vacuum chamber is maintained at a pressure of about 100 mmHg or less.

Claim 6

Dependent Claim 30 words

The method of claim 1 wherein the inside wall of the vacuum chamber is coated with a material which does not stick to the cut rubber or rubbery polymer material.

Claim 7

Dependent Claim 10 words

The method of claim 5 wherein said material is polyltetrafluoroethylene.

Claim 8

Dependent Claim 36 words

The method of claim 1 wherein the cut rubber or rubbery polymer material is fed into a feed inlet of the second extruder by a feed device provided at the feed inlet of the second extruder.

Claim 9

Dependent Claim 28 words

The method of claim 1 wherein a crosshead of the second extruder is provided with a long land die having a land length of at least 50 mm.

Claim 10

Dependent Claim 28 words

The method of claim 1 wherein a crosshead of the second extruder is provided with a long land nipple having a land length of at least 25 mm.

Claim 11

Dependent Claim 24 words

The method of claim 1 wherein said curing means is a curing bath containing a liquid heating medium kept at about 150* to 250*C.

Claim 12

Dependent Claim 17 words

The method of claim 10 wherein said heating medium is a molten eutectic mixture of inorganic salts.

Claim 13

Dependent Claim 45 words

The method of claim 11 wherein the covered core cured by a molten eutectic mixture of inorganic salts is washed with warm water held at a temperature not lower than about 60*C. to thereby remove the salts remaining on the surface of the cured layer.

Claim 14

Dependent Claim 21 words

The method of claim 12 wherein said remaining salts are removed by also contacting the covered core with a rotating brush.

Claim 15

Dependent Claim 17 words

The method of claim 12 wherein said remaining salts are removed by the application of ultrasonic vibrations.

Claim 16

Dependent Claim 16 words

The method of claim 10 wherein said heating medium is a molten eutectic mixture of metals.

Claim 17

Dependent Claim 21 words

The method of claim 10 wherein said heating medium is an oroganic liquid having a boiling point above the curing temperature.

Claim 18

Dependent Claim 65 words

The method of claim 1 wherein the curing means comprises a trough containing a liquid heating medium and wherein the core covered with the uncured rubber or rubbery polymer material by the second extruder is introduced into the trough through an inlet provided in a side wall of the trough, and the heating medium flows out from the inlet and is collected in a receiver.

Claim 19

Dependent Claim 13 words

The method of claim 10 wherein the heating medium comprises a fluidized bed.

Claim 20

Dependent Claim 13 words

Th method of claim 1 wherein the heating medium comprises a heated gas.

Claim 21

Dependent Claim 14 words

The method of claim 1 wherein the heating medium comprises ultrasonic high frequency radiation.

Claim 22

Dependent Claim 17 words

The method of claim 1 wherein the uncured rubber or rubbery polymer material contains a curing agent.

Claim 23

Independent Claim 284 words

A method for manufacturing a multilayered fabricated article which comprises extruding an uncured rubber or extrudable and then curable plastic composition by a first extruder into a vacuum chamber, reducing the size of the extruded composition in said chamber by a cutter, feeding the thus cut composition to a second extruder while maintaining the sliced composition under reduced pressure, extruding the composition by the second extruder around a core which has been dried and heated prior to said second extrusion, and introducing the covered core without substantially bending the same into curing means containing a heating medium, wherein said covered core is contacted with the heating medium which elevates the temperature of the uncured rubber or plastic composition, whereby the uncured rubber or plastic layer around the core is heated and cured at substantially atmospheric pressure, said curing means comprising an upper trough and a lower trough, both of which contain a liquid heating medium, and wherein the core covered with the uncured rubber or plastic composition by the second extruder is firstly introduced into the upper trough through an inlet provided in a side wall of the upper trough, advanced in the upper trough horizontally while maintained in the straightened condition while contacting only the heating medium, withdrawn from the upper trough through an outlet provided in a wall of the upper trough and then introduced into the lower trough located below the upper trough via a turning wheel, said first and second extruders being provided such that the sum of the L/D ratio of the first extruder and the L/D ratio of the second extruder does not exceed 24, and with the L/D ratio of said first extruder being at least 8.

Claim 24

Independent Claim 284 words

A method for manufacturing a multilayered fabricated article which comprises extruding an uncured rubber or extrudable and then curable plastic composition by a first extruder into a vacuum chamber, reducing the size of the extruded composition in said chamber by a cutter, feeding the thus cut composition to a second extruder while maintaining the sliced composition under reduced pressure, extruding the composition by the second extruder around a core which has been dried and heated prior to said second extrusion, and introducing the covered core without substantially bending the same into curing means containing a heating medium, wherein said covered core is contacted with the heating medium which elevates the temperature of the uncured rubber or plastic composition, whereby the uncured rubber or plastic layer around the core is heated and cured at substantially atmospheric pressure, said curing means comprising an upper trough and a lower trough, both of which contain a liquid heating medium, and wherein the core covered with the uncured rubber or plastic composition by the second extruder is firstly introduced into the upper trough through an inlet provided in a side wall of the upper trough, advanced in the upper trough horizontally while maintained in the straightened condition while contacting only the heating medium, withdrawn from the upper trough through an outlet provided in a wall of the upper trough and then introduced into the lower trough located below the upper trough via a turning wheel, said first and second extruders being provided such that the sum of the L/D ratio of the first extruder and the L/D ratio of the second extruder does not exceed 24, and with the L/D ratio of said first extruder being at least 8.

Claim 25

Dependent Claim 36 words

The method of claim 22 wherein the heating medium flowing out from the inlet of the upper trough falls into the lower trough, and the medium in the lower trough is circulated into the upper trough.

Claim 26

Dependent Claim 43 words

The method of claim 22 wherein the core covered with the rubber or plastic composition which has been introduced into the lower trough is advanced horizontally through the heating medium in the lower trough, and is then again introduced into the upper trough.

Claim 27

Dependent Claim 46 words

The method of claim 22 wherein the core covered with the rubber or plastic composition which has been introduced into the lower trough is advanced horizontally through the heating medium in the lower trough, and then again advanced through the heating medium in the lower trough.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1978-10-06	1979-04-07	1979-10-07	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1982-10-06	1983-04-07	1983-10-07	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1986-10-06	1987-04-07	1987-10-07	$7700.00	Window Closed / Lapsed

Method of manufacturing multilayered articles

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