EP0141614A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Surface treatment of paper and paperboard
Assignee: BLACK-CLAWSON INTERNATIONAL Ltd
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Filing: 1984-10-24
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Granted: —
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Expires: 2004-10-24
Abstract
Abstract Paper or paperboard (10) which has been thoroughly dried, but not calendered is provided with a smooth surface by rewetting a thin layer along one surface thereof and then pressing the resulting damp surface against a substantial portion of the surface of a heated smooth-surfaced drying cylinder (20). This technique provides the web (10) with a surface comparable in smoothness with that which can be obtained by calendaring, but without the degree of compaction which occurs in calendaring, due to the fact that with the major portion of the web dried, it is highly resistant to such compaction.
Inventors
- 👤 Brian William Attwood
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 07:43
CPC Classifications
D; D21; D21G; D21G1/00; D21G1/0073; D21G1/0093
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
118 words
A method of producing a smooth surface on a web of paper or paperboard characterised by the steps of: (a) producing an unfinished web (10) of paper or paperboard having a solids content of at least substantially 70% throughout the major portion of the thickness thereof measured from one surface thereof and having a lower solids content in a layer including the other surface thereof and constituting a minor portion of the thickness thereof, (b) guiding the web (10) into partially wrapping relation with at least one heated cylinder (20) with said lower solids content surface in contact with said cylinder, and (c) pressing said web into intimate contact with the cylinder (20) over the wrapped portion thereof.
Claim 2
Independent Claim
118 words
A method of producing a smooth surface on a web of paper or paperboard characterised by the steps of: (a) producing an unfinished web (10) of paper or paperboard having a solids content of at least substantially 70% throughout the major portion of the thickness thereof measured from one surface thereof and having a lower solids content in a layer including the other surface thereof and constituting a minor portion of the thickness thereof, (b) guiding the web (10) into partially wrapping relation with at least one heated cylinder (20) with said lower solids content surface in contact with said cylinder, and (c) pressing said web into intimate contact with the cylinder (20) over the wrapped portion thereof.
Claim 3
Dependent Claim
87 words
A method according to claim 1, characterised by the steps of:- (a) producing an unfinished web of paper or paperboard having a solids content of at least substantially 70% and preferably approximately 80% throughout the entire thickness thereof, and (b) applying an aqueous liquid to said other surface of said web at a rate sufficient to rewet only a layer of said web adjacent said other surface thereby to produce said layer of lower solids content constituting a minor portion of the thickness of said web (10).
Claim 4
Dependent Claim
24 words
A method according to claim 1 or 2, characterised in that the pressing step is carried out by maintaining the web (10) under tension.
Claim 5
Dependent Claim
54 words
A method according to claim 1 or 2, characterised in that the pressing step is carried out by means of an endless belt (22) which is guided into overlying relation with at least a part of the cylinder-wrapping portion of the web (10) and is maintained under tension creating pressure against said cylinder (20).
Claim 6
Dependent Claim
41 words
A method according to claim 1,2,3 or 4, characterised in that the pressing step is carried out by means of at least one pressure roller (21) forming a bare pressure nip with the cylinder (20) through which the web (10) passes.
Claim 7
Dependent Claim
40 words
A method according to claim 4, characterised by the step of augmenting the pressure of the belt (22) against the cylinder (20) by a plurality of pressure rollers (21,23,24) forming pressure nips with said cylinder through which said belt passes.
Claim 8
Dependent Claim
74 words
A method according to claim 1 or 2, characterised in that the pressing step is carried out by means of a pressure roller (21) forming a bare pressure nip with the cylinder (20) through which the web (10) passes, and by means of an endless belt (22) which is guided into overlying relation with a part of the cylinder-wrapping portion of the web (10) and is maintained under tension creating pressure against the cylinder.
Claim 9
Independent Claim
67 words
A method according to any preceding claim characterised by the steps of: (a) guiding an endless band (33) having a textured surface into overlying relation with at least a part of the cylinder-wrapping portion of the web (10), and (b) maintaining said band in pressure engagement with the outer surface of said part of said cylinder-wrapping portion of the web to emboss a corresponding textured surface thereon.
References Cited (Backward Citations)
No citation records indexed.
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