Paper making and fiber liberation – Processes and products – Non-fiber additive
Patent
1998-05-07
2000-02-08
Chin, Peter
Paper making and fiber liberation
Processes and products
Non-fiber additive
162175, 162158, 162129, 162135, 162142, 1061251, 1061351, 1061241, D21H 1100, D21F 1100, C09D 400, C08L 100, C08L 8900
Patent
active
060224509
DESCRIPTION:
BRIEF SUMMARY
The invention resides in the field of paper and cardboard manufacturing. In particular, the invention relates to the use of a combination of starch- and protein-containing material in paper and cardboard. In fact, in this specification and the claims, the term `paper` is meant to include cardboard as well.
Traditionally, starches are used on a large scale and in large volumes in the paper and cardboard industry. In the production of coated paper, which is substantially used as graphic paper in the fine-paper industry, it is used as, inter alia, binding agent in the coating. In general, this starch is a modified starch.
In addition, starch is used as admixture for improving the strength properties, and in particular the dry-strength properties, of the paper. For that purpose, starches conventionally used in the paper industry and anionic and cationic derivatives of these starches are used, for which reference can be made to, for instance, EP-A-0 545 228 and WO-A-94/05855.
In this connection, further reference can be made to Kirk-Othmer, Encyclopedia of Chemical Technology, Third Edition (1981), John Wiley & Sons, Volume 16, p. 803 ff, in particular pp. 814-819.
In the most current uses of starch as fiber-reinforcing component, it is either introduced--usually in the form of cationic starch--into the mass of the paper in the wet portion of the paper process, or impregnated--substantially in the form of solubilized native starch--into the paper fiber mass by means of the so-called size press.
These known strength-improving additives are advantageous, both in an economical and in a technical or technological sense; they give the paper or the cardboard an added value. Apart from providing an added value in conventional paper and cardboard processes, the need for additives for increasing the strength is enhanced in particular by the increasing use of weaker fibers, old paper that is reused more and more often, and a further increasing use of fillers instead of fibers in this old paper, resulting in a decreasing strength potential, and the decreasing availability of strong, long-fiber components in the base pulp for paper.
Actually, it is now emphasized that the invention is not limited to "waste-based" paper. The invention extends across the entire area of paper and cardboard manufacture, including paper based on "virgin fiber".
The known starch-based additives can enter into large-scale interactions with the cellulose groups of paper fibers. Thus, an increase of the number of bonds between the mutual paper fibers is formed, which reinforces the fiber-fiber bond and, accordingly, improves the strength properties of the final product.
In conventional processes wherein starches are used as strengthener, strict requirements are imposed on the protein content that may be present in the starch product used. In particular, native starch used for the manufacture of paper, substantially native wheat-, corn- or potato starch, is supplied with an additional specification for maximum protein contents of 0.3-0.5 wt. %, calculated on the dry substance. Higher protein contents are supposed to have a contaminating effect and to cause lump formation and depositions in the system. For instance, the dispersion of gluten (the protein fraction in wheat flour) leads to lumping and foam formation. These drawbacks occur to an enlarged extent when these proteins are exposed to higher temperatures in the paper manufacturing process.
The starch which forms the basic material for presently used starch additives in paper is recovered from a large number of vegetable sources, for instance from grains, such as wheat, corn and rice; from tubers, such as potatoes and tapioca; or from other plant parts, such as sago.
From the above-mentioned vegetable sources, the starch is released by the use of a combination of mechanical steps, purifying steps and drying steps. The separated protein-containing fractions, as well as other by-product fractions, are discharged. The starch purification involves the release of many waste flows, such as water flow
REFERENCES:
patent: 1622496 (1927-03-01), Davidson et al.
patent: 1755744 (1930-04-01), Munktell
patent: 2466172 (1949-04-01), Kesler
patent: 2559901 (1951-07-01), Schied
patent: 3163549 (1964-12-01), Vollink et al.
patent: 3166466 (1965-01-01), Puydak
patent: 3211564 (1965-10-01), Lauterbach
patent: 3859108 (1975-01-01), Ware et al.
patent: 4940514 (1990-07-01), Stange et al.
patent: 5011741 (1991-04-01), Hoffman
Kuypers Gerardus Henricus Andreas
Maessen Matheus Petrus Marie
Van Kessel Louis Peter Marie
Chin Peter
Roermond Papier B.V.
Walls Dionne A.
LandOfFree
Paper and cardboard comprising starch- and protein-containing ma does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Paper and cardboard comprising starch- and protein-containing ma, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Paper and cardboard comprising starch- and protein-containing ma will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1677984