The investigations of polyacrylamide concerning the paper making have been summarized. The acrylamide has been polymerized by an inverse emulsion polymerization. The modification of polyacrylamide by condensation with acetaldehyde has been studied, and the flocculation ability of the modified polymer has been discussed. For the purpose of obtaining the cationic derivatives, acrylamide has been copolymerized with 2-methyl-N-vinylimidazole. N-Dimethyl a-minoethyl polyacrylamide and polyacrylic hydrazide have also been prepared with the same intention by the polymer analogous substitution of polyacrylamide. The applications of those cationic polymers to the paper making as wet end additives have deen investigated. A complex polyelectrolyte has been prepared by combining the partially hydrolyzed polyacrylamide with polyethyleneimine. The complex polymer has been found to serve as a good flocculation agent and a wet end additive. The graft copolymerizations of acrylamide onto cellulose and petroleum resine have been also mentioned.

View full abstract

The body paper of hat was prepared from a 50/50 blend of SWP (synthetic pulp of polyethlene type, Mitsui Zellerbach K. K.) and NBKP, and was carried out beater coloring with organic pigments and alum experimentally. The vat-lined two ply paper was dry creped and worked upon and formed the sample into the summer millinery experimentally.
According to an end user (milliner), the colored summer millinery well satisfactory an aethetic sense for practical usage.
The physical properties of dry creped SWP two ply with pigments are shown in Table 2.
Light fastness and waterbleed fastness or water-resistance are shown in Table 3.

View full abstract

In making dissolving pulp from mangrove wood, one of the important problems is how to decrease a large quantity of EDTA ash in the pulp. This paper reports the relation between screening and elimination of EDTA ash in the pulp.
We made dissolving pulp from mangrove wood by an ordinary screening and bleaching, and found that EDTA ash in it was abnormally high. So we tried fiber classification of each simple in the screening process and analyzed EDTA ash in each fraction. As a result of the examination, we found that EDTA ash was plentiful in the fine fraction under 150 meshes in every process. We also found that this EDTA ash was caused by crystals of Ca-oxalate which were included in the ray parenchyma cells of wood. By slight defibration of the digested stock, these ray cells were separated from the fibers in the pulp and disintegrated into the fraction under 150 meshes. Therefore, by selectively separating these fines, especially the square cells which included crystals, we could eliminate EDTA ash in mangrove pulp. By our experiment, centri-cleaner was very efficient in separating fines. In these treatments, pulp yield from mangrove wood became a little lower than that from Japanese hard wood.

View full abstract