Water-dispersible paper

• US 8,877,678 B2
• Filed: 07/28/2011
• Issued: 11/04/2014
• Est. Priority Date: 07/28/2010
• Status: Active Grant

• Current Assignee: Nippon Paper Papylia Co., Ltd. (Nippon Paper Group Incorporated)
• Original Assignee: Nippon Paper Papylia Co., Ltd. (Nippon Paper Group Incorporated)
• Inventors: Koyama, Munenaka, Ishino, Yoshiaki, Kishimoto, Masaki
• Primary Examiner(s): Hess, Bruce H
• Application Number:
  US13/812,824
• Publication Number:
  US 20140045684A1
• Time in Patent Office: 1,195 Days
• Field of Search: 503200-226, 428/32.21, 428/211.1, 428/537.5
• US Class Current: 503/200
• CPC Class Codes: B41M 5/41 Base layers supports or substrates
• CPC Class Codes: B41M 5/508 Supports
• CPC Class Codes: D21H 11/00 Pulp or paper, comprising cellulose or lignocellulose fibres of natural origin only
• CPC Class Codes: D21H 11/20 Chemically or biochemically modified fibres
• CPC Class Codes: D21H 13/02 Synthetic cellulose fibres
• CPC Class Codes: D21H 19/12 applied as a solution using water as the only solvent, e.g. in the presence of acid or alkaline compounds
• CPC Class Codes: D21H 19/36 Coatings with pigments D21H19/66 takes precedence; metal powder D21H19/06
• CPC Class Codes: G09F 3/0291 Labels or tickets undergoing a change under particular conditions, e.g. heat, radiation, passage of time
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]
• CPC Class Codes: Y10T 428/24934 including paper layer
• CPC Class Codes: Y10T 428/2848 Three or more layers
• CPC Class Codes: Y10T 428/31993 Of paper

Abstract

An object of the present invention is to provide a water dispersion paper having quick water dispersion property and high strength (printability) and whose paper surface pH is 6 to 8 (neutral range), and also to provide a water dispersion coated paper designed to ensure quick water dispersion property and prevent discoloration over time.

A water dispersion paper made of wood pulp and/or non-wood pulp, wherein said water dispersion paper is characterized in that purified pulp containing α-cellulose by 88 percent by weight or more accounts for 15 to 95 percent by weight of all pulp, as well as a water dispersion coated paper having a water-soluble coating layer on said water dispersion paper.

Claims

1. A water dispersion coated paper constituted by:

a base material which is a water dispersion paper made of wood pulp and/or non-wood pulp, wherein purified pulp containing α

-cellulose by 88 percent by weight or more accounts for 15 to 95 percent by weight of all pulp, and

a coating layer provided on top, whose primary constituent is water-based coating material.

2. A water dispersion coated paper according to claim 1, wherein the coating layer is a thermo-sensitive recording layer, inkjet recording layer or general printing layer.

3. A water dispersion coated paper according to claim 1, wherein a water-soluble sealer layer is provided between the base material and the coating layer and/or on the uncoated side of the base material.

4. A water dispersion coated paper according to claim 1, wherein water-soluble or water-redispersible pressure-sensitive adhesive is used to provide a pressure-sensitive adhesive layer on another side of the base material opposite to one side on which the coating layer is formed.

5. A water dispersion coated paper according to claim 4, wherein the water dispersion coated paper is a label displaying information of food material, etc., on the coating layer.

6. A water dispersion coated paper according to claim 1, wherein the water dispersion coated paper is a printing paper for confidential documents.

7. A water dispersion coated paper constituted by:

a base material which is a water dispersion paper made of wood pulp and/or non-wood pulp, wherein said water dispersion paper is characterized in that purified pulp containing hemi-cellulose by less than 12 percent by weight accounts for 15 to 95 percent by weight of all pulp, and

a coating layer provided on top, whose primary constituent is water-based coating material.

8. A water dispersion coated paper according to claim 7, wherein the coating layer is a thermo-sensitive recording layer, inkjet recording layer or general printing layer.

9. A water dispersion coated paper according to claim 7, wherein a water-soluble sealer layer is provided between the base material and the coating layer and/or on the uncoated side of the base material.

10. A water dispersion coated paper according to claim 7, wherein water-soluble or water-redispersible pressure-sensitive adhesive is used to provide a pressure-sensitive adhesive layer on another side of the base material opposite to one side on which the coating layer is formed.

11. A water dispersion coated paper according to claim 10, wherein the water dispersion coated paper is a label displaying information of food material, etc., on the coating layer.

12. A water dispersion coated paper according to claim 7, wherein the water dispersion coated paper is a printing paper for confidential documents.