Uncoated paper web for printing and method for making and using same

• US 4,549,930 A
• Filed: 04/02/1980
• Issued: 10/29/1985
• Est. Priority Date: 04/06/1979
• Status: Expired due to Term

• Current Assignee: Stora Feldmuehle Aktiengesellschaft
• Original Assignee: Feldmuhle AG
• Inventors: Dessauer, Guido
• Primary Examiner(s): Chin, Peter
• Application Number:
  US06/136,557
• Time in Patent Office: 2,036 Days
• Field of Search: 162/181 R, 162/181 D, 162/134, 162/206, 162/181.8
• US Class Current: 162/134
• CPC Class Codes: B41M 1/36 on pretreated paper, e.g. parchment, oiled paper, paper for registration purposes B41M5/50 takes precedence
• CPC Class Codes: D21H 17/68 siliceous, e.g. clays

Abstract

An uncoated paper web suitable for rotogravure printing with water-immiscible solvent-containing inks, the fibers of the web being partially or totally enveloped with a clay hydrogel, the clay being hydratable, colloidal and film-forming. The web provides superior printing results in rotogravure printing. A method for printing the web is disclosed.

Claims

1. In a method for rotogravure printing on a paper using a printing ink containing water-immiscible solvents, the improvement which comprises the paper comprising a fibrous paper web, the fibers of which are partially or totally enveloped with a coating of a clay hydrogel which clay is hydratable, is colloidal and is film-forming, said web having an area weight of from about 45 to 100 g/m², a density of from about 0.95 to 1.2 g/cc and a smoothness of from about 600 to 1500 Bekk seconds and containing conventional inorganic fillers in amounts of more than 15% by weight expressed as the ash content wherein the hydratable, film-forming, colloidal clay contains a montmorillonite mineral selected from the group consisting of minerals in which the ratio of sodium and calcium is between 40:

60 and 60;

40 and minerals whose ion portion is composed of up to 40% magnesium ions with the remainder of the ion portion being sodium ions.

2. The method of claim 1 wherein the clay is present in an amount of from about 1.2 to 8 weight percent, based on the total weight of the paper.

3. The method of claim 1 or 2 wherein the clay is selected from the group consisting of bentonite, attapulgite, sepiolite, and mixtures thereof.

4. The method of claim 1 or 2 wherein conventional inorganic fillers are present in amounts of more than 15% by weight expressed as the ash content.

5. The method of claim 1 or 2 wherein conventional inorganic fillers are present in amounts of more than 15% by weight expressed as the ash content, selected from the group consisting of kaolin, calium carbonate, talc and titanium dioxide.

6. The method of claim 1 or 2 wherein the chemical woodpulp content, based on the total amount of fibrous material, is greater than 10%.

7. The method of claim 1 or 2 wherein the paper has an area weight of about 55 to 70 g/m², a density of about 1.0 to 1.15 g/cc, a Bekk smoothness of 900 to 1,200 seconds and the following composition:

75 to 80 weight percent of mechanical woodpulp,

20 to 25 weight percent of chemical woodpulp,

18 to 26 weight percent of kaolin, and

1.6 to 3.5 weight percent of hydratable, colloidal, film-forming clays, based on the total weight of material.

8. The method of claim 1 or 2 wherein macromolecules of polyglycols with a molecular weight of 5,000 to 100,000 are connected to the hydratable, film-forming, colloidal clays.