초록 ▼

Apparatus for embossing web material such as a heated thermoplastic web material comprises first and second embossing members each having a resilient embossing surface, and means mounting the embossing members for relative movement to define a roll nip between them. The resilient surface of the firs

Apparatus for embossing web material such as a heated thermoplastic web material comprises first and second embossing members each having a resilient embossing surface, and means mounting the embossing members for relative movement to define a roll nip between them. The resilient surface of the first embossing member has a primary embossing pattern thereon and is of harder durometer than the resilient surface of the second embossing member. Both resilient surfaces are soft enough to be temporarily deformed in the roll nip to press the web material between them into surface conforming contact with the primary embossing pattern. The temporary deformation also helps to expel air from between the web material and the primary embossing pattern to insure surface conforming contact of the web to the embossing pattern. A secondary embossing pattern is provided on the resilient surface of the second embossing member and is of lesser depth than the primary embossing pattern. The temporary deformation assists in providing full contact with both patterns. A method of embossing the material includes heating the thermoplastic web material to a temperature within its softening range, introducing the heated material to a nip formed between the first and second embossing members, and allowing the embossed material to cool to set the pattern before removing it from the first embossing member.

대표청구항 ▼

In an apparatus for embossing a thermoplastic web material and including a first embossing member having a resilient embossing surface providing a primary embossing pattern of a first depth; a second embossing member having a resilient surface providing a secondary embossing pattern of a lesser dept

In an apparatus for embossing a thermoplastic web material and including a first embossing member having a resilient embossing surface providing a primary embossing pattern of a first depth; a second embossing member having a resilient surface providing a secondary embossing pattern of a lesser depth than said first depth of said primary embossing pattern; means mounting said first and second embossing members for relative movement to define a roll nip therebetween; means to pass a heated thermoplastic web material through said nip to form an embossed pattern thereon, the improvement wherein said resilient surface of said first embossing member has a hardness of about 50 to 85 durometer on the Shore A scale and is at least about 5 durometer on the Shore A scale harder than said resilient surface of said second embossing member, the resilient surface of said second member having a hardness of about 45 to 80 durometer on the Shore A scale and said roll nip exerting sufficient pressure to temporarily deform both said resilient surfaces thereat, the associated web material being pressed in said nip between said resilient surfaces into surface-conforming contact with said first embossing member and remaining in contact with said primary embossing pattern thereof upon passage from said nip; and means for stripping the associated web material from said primary embossing pattern of said first embossing member at a point spaced from said nip in the direction of rotation of said first embossing member. The method of claim 13 wherein said resilient embossing surfaces are provided by silicone rubber.