US4315965A — Method of making nonwoven fabric and product made…

Claim 1

Independent Claim 115 words

A method of autogenously bonding a nonwoven web formed predominantly of thermoplastic fibers, characterized by the steps of directing heat into the web from only one surface thereof to preheat the web, and then directing the preheated web through a bonding nip formed between opposed rolls, one of said rolls being hotter than the other roll, being capable of heating the web surface it engages to a temperature above the melt point of the thermoplastic fibers and being positioned to engage the surface of the web opposite the one into which heat was directed during the preheating operation; said web being preheated by means completely independent of the opposed rolls that form the bonding nip.

Claim 2

Independent Claim 115 words

A method of autogenously bonding a nonwoven web formed predominantly of thermoplastic fibers, characterized by the steps of directing heat into the web from only one surface thereof to preheat the web, and then directing the preheated web through a bonding nip formed between opposed rolls, one of said rolls being hotter than the other roll, being capable of heating the web surface it engages to a temperature above the melt point of the thermoplastic fibers and being positioned to engage the surface of the web opposite the one into which heat was directed during the preheating operation; said web being preheated by means completely independent of the opposed rolls that form the bonding nip.

Claim 3

Dependent Claim 37 words

The method of claim 1 characterized by forming the bonding nip between an embossing roll having raised land areas on its surface and a back-up roll having a resilient surface, said embossing roll being the hotter roll.

Claim 4

Dependent Claim 22 words

The method of claim 2 characterized by the step of employing infrared radiation upstream of the bonding nip to preheat the web.

Claim 5

Independent Claim 50 words

The method of claims 1, 2 or 3, characterized by heating the surface of the web with the hotter roll to form autogenous bonds that are predominately melt bonds penetrating only partially through the web thickness, and forming autogenous bonds on the preheated surface that are over 90% stick bonds.

Claim 6

Dependent Claim 23 words

The method of claim 4 characterized by forming autogenous bonds on the preheated surface of the web that are substantially 100% stick bonds.

Claim 7

Dependent Claim 21 words

The method of claim 4 characterized by forming the bonded web at a speed in excess of 30.48 m/minute (100 ft/minute).

Claim 8

Dependent Claim 21 words

The method of claim 4 characterized by forming the bonded web at a speed in excess of 91.44 m/minute (300 ft/minute).

Claim 9

Independent Claim 128 words

A method of autogenously bonding a nonwoven web formed predominantly of thermoplastic fibers and having a basis weight no greater than about 0.0339 kg/m 2 (1 oz./yd. 2 ), characterized by the steps of directing heat into the web from only one surface thereof to preheat the web, and then directing the preheated web through a bonding nip formed in part by a heated roll that is capable of heating the web surface it engages to a temperature above the melt point of the thermoplastic fiber and being positioned to engage the surface of the web opposite the one into which heat was directed during the preheating operation for creating autogenous bonds that, on the engaged surface, are substantially melt bonds penetrating only partially through the web thickness.

Claim 10

Independent Claim 128 words

A method of autogenously bonding a nonwoven web formed predominantly of thermoplastic fibers and having a basis weight no greater than about 0.0339 kg/m 2 (1 oz./yd. 2 ), characterized by the steps of directing heat into the web from only one surface thereof to preheat the web, and then directing the preheated web through a bonding nip formed in part by a heated roll that is capable of heating the web surface it engages to a temperature above the melt point of the thermoplastic fiber and being positioned to engage the surface of the web opposite the one into which heat was directed during the preheating operation for creating autogenous bonds that, on the engaged surface, are substantially melt bonds penetrating only partially through the web thickness.

Claim 11

Dependent Claim 64 words

The method of claim 8 characterized by the step of establishing the bonding nip between said heated roll and an opposed back-up roll having a lower surface temperature than said heated roll, and controlling the temperature of the opposed rolls, as well as the time and pressure in the bonding nip to form over 90% stick bonds on the preheated surface of the web.

Claim 12

Dependent Claim 12 words

The method of claim 9 characterized by forming substantially 100% stick bonds.

Claim 13

Dependent Claim 21 words

The method of claim 8 characterized by forming the bonded web at a speed in excess of 30.48 m/minute (100 ft/minute).

Claim 14

Dependent Claim 21 words

The method of claim 8 characterized by forming the bonded web at a speed in excess of 91.44 m/minute (300 ft/minute).

Claim 15

Dependent Claim 37 words

The method according to claim 8, 9, 10, 11 or 12 characterized by providing the surface engaged by the hotter roll with autogenous bonds that are virtually all melt bonds extending only partially through the web thickness.

Claim 16

Dependent Claim 11 words

A nonwoven web made according to the method of claim 1.

Claim 17

Dependent Claim 31 words

A nonwoven web made according to the method of claim 1, and having a cross-machine-direction wet tensile energy absorption level of at least about 3.15 m-kg/m 2 (80 inch-gram/in 2 ).

Claim 18

Dependent Claim 42 words

A nonwoven web made according to the method of claim 1 and having a cross-machine-direction wet tensile energy absorption level of at least about 3.15 m-kg/m 2 (80 inch-grams/in. 2 ) and a cross-machine-direction wet tensile strength exceeding 9.83 kg/m (250 gms./in.).

Claim 19

Dependent Claim 11 words

A nonwoven web made according to the method of claim 9.

Claim 20

Dependent Claim 31 words

A nonwoven web made according to the method of claim 9, and having a cross-machine-direction wet tensile energy absorption level of at least about 3.15 m-kg/m 2 (80 inch-gram/in 2 ).

Claim 21

Dependent Claim 42 words

A nonwoven web made according to the method of claim 9, and having a cross-machine-direction wet tensile energy absorption level of at least about 3.15 m-kg/m 2 (80 inch-grams/in. 2 ) and a cross-machine-direction wet tensile strength exceeding 9.83 kg/m (250 gms./in.).

Claim 22

Independent Claim 129 words

A method of making an autogenously bonded web comprising the steps of: (a) forming a nonwoven web consisting predominantly of thermoplastic fibers; (b) preheating the formed web from one surface thereof; (c) directing the preheated web to an embossing station comprising a heated embossing roll and a backup roll having a resilient surface; (d) passing the web through the nip formed by the heated embossing roll and the backup roll, the heated embossing roll contacting the other surface of the preheated web; and (e) controlling the temperature of the preheating step, the temperature of the heated embossing roll and the bonding pressure so that predominately stick bonds are formed in said one surface of the web and predominately melt bonds are formed in said other surface of the web.

Claim 23

Independent Claim 129 words

A method of making an autogenously bonded web comprising the steps of: (a) forming a nonwoven web consisting predominantly of thermoplastic fibers; (b) preheating the formed web from one surface thereof; (c) directing the preheated web to an embossing station comprising a heated embossing roll and a backup roll having a resilient surface; (d) passing the web through the nip formed by the heated embossing roll and the backup roll, the heated embossing roll contacting the other surface of the preheated web; and (e) controlling the temperature of the preheating step, the temperature of the heated embossing roll and the bonding pressure so that predominately stick bonds are formed in said one surface of the web and predominately melt bonds are formed in said other surface of the web.

Claim 24

Dependent Claim 17 words

The method of claim 20 additionally comprising the step of controlling the temperature of the backup roll.

Claim 25

Dependent Claim 12 words

An autogenously bonded web made according to the method of claim 20.

Claim 26

Dependent Claim 22 words

The autogenously bonded web of claim 22 characterized in that the autogenous bonds in said one surface are over 90% stick bonds.

Claim 27

Dependent Claim 24 words

The autogenously bonded web of claims 22 or 23 characterized in that the autogenous bonds in said other surface are over 80% molten bonds.

Claim 28

Independent Claim 135 words

A method of making an autogenously bonded web comprising the steps of: (a) forming a nonwoven web consisting predominately of thermoplastic fibers; (b) preheating the formed unrestrained web from one surface thereof, while the web is unrestrained; (c) directing the preheated web to an embossing station comprising a heated embossing roll and a backup roll having a resilient surface; (d) passing the web through the nip formed by the heated embossing roll and the backup roll, the heated embossing roll contacting the other surface of the preheated web; and (e) controlling the temperature of the preheating step, the temperature of the heated embossing roll and the bonding pressure so that predominately stick bonds are formed in said one surface of the web and predominately melt bonds are formed in said other surface of the web.

Claim 29

Independent Claim 135 words

A method of making an autogenously bonded web comprising the steps of: (a) forming a nonwoven web consisting predominately of thermoplastic fibers; (b) preheating the formed unrestrained web from one surface thereof, while the web is unrestrained; (c) directing the preheated web to an embossing station comprising a heated embossing roll and a backup roll having a resilient surface; (d) passing the web through the nip formed by the heated embossing roll and the backup roll, the heated embossing roll contacting the other surface of the preheated web; and (e) controlling the temperature of the preheating step, the temperature of the heated embossing roll and the bonding pressure so that predominately stick bonds are formed in said one surface of the web and predominately melt bonds are formed in said other surface of the web.

Claim 30

Dependent Claim 95 words

An autogenously bonded nonwoven web, said web, prior to bonding being weaker in the cross-machine-direction than in the machine-direction, characterized in that the autogenous bonds on one surface include substantially continuous molten bonds extending in a direction, in the plane of the web, for reinforcing the web in the cross-machine-direction, said molten bonds extending only partially through the thickness of the web, said bonded web having a cross-machine-direction wet tensile energy absorption level of at least about 3.15 m-kg/m 2 (80 inch-grams/in 2 ) and a cross-machine-direction wet tensile strength exceeding 9.83 kg/m (250 gms/in.).

Claim 31

Dependent Claim 95 words

An autogenously bonded nonwoven web, said web, prior to bonding being weaker in the cross-machine-direction than in the machine-direction, characterized in that the autogenous bonds on one surface include substantially continuous molten bonds extending in a direction, in the plane of the web, for reinforcing the web in the cross-machine-direction, said molten bonds extending only partially through the thickness of the web, said bonded web having a cross-machine-direction wet tensile energy absorption level of at least about 3.15 m-kg/m 2 (80 inch-grams/in 2 ) and a cross-machine-direction wet tensile strength exceeding 9.83 kg/m (250 gms/in.).

Claim 32

Dependent Claim 21 words

The autogenously bonded nonwoven web of claim 26 characterized by a basis weight no greater than about 0.0339 kg/m 2 .

Claim 33

Dependent Claim 26 words

The autogenously bonded nonwoven web of claim 26 or 27, characterized in that the opposed web surface has autogenous bonds that are over 90% stick bonds.

Claim 34

Dependent Claim 24 words

The autogenously bonded nonwoven web of claim 28, characterized in that the opposed web surface has autogenous bonds that are substantially 100% stick bonds.

Claim 35

Dependent Claim 23 words

The autogenously bonded nonwoven web of claim 28, characterized in that the autogenous bonds on said one surface are over 80% molten bonds.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1985-02-15	1985-08-17	1986-02-16	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1989-02-15	1989-08-17	1990-02-16	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1993-02-15	1993-08-17	1994-02-16	$7700.00	Window Closed / Lapsed

Method of making nonwoven fabric and product made thereby having both stick bonds and molten bonds

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