Impregnation of paper

Ethyl silicate (tetraethoxysilane) is often used without modification as a water-repellent material for concrete and masonry in general. All, or nearly all. the ethoxyl groups are hydrolyzed by the moisture of the air to form cross-linked watcr-rcpcllcnt polymers. The material is applied in desirable thickness, dissolved in some volatile solvent which soon evaporates. Silicone resins which arc partially condensed before application, or even fully condensed, can also be used here. In the latter case, hardness is achieved on evaporation of the solvent. Certain silicone resins arc useful as hydrophobic agents for the impregnation of paper and fabrics. 

Impregnation of Paper Web. The paper web is impregnated from one or both sides with an FWA solution that often contains other additives. In the size press, the paper is therefore brightened only on the surface, thus economizing on brightener material. Examples of products employed in this way are 24, 26, and 28-31. 

The phenol/furfural resins have a greater hydrocarbon solvent tolerance than phenol/formaldehyde resins. This is an advantage in the preparation of resin solutions used for the impregnation of paper or cloth for laminating. 

The production rules for the impregnation of paper coated by PE, PS, parafEn or butadiene-styrene latex with Cl are reflected in Russian State Standard 16295 [32]. In particular, such paper has been manufactured since 1970 at Joint Stock Co. Technical Paper, Rybinsk, Russia. 

Uses Vehicle for trade sales paints, factory finishes (wood, composition board), and in coatings and impregnation of paper and textiles Features Colloid-free microparficle size emulsion chemical and mechanical sfabilify produces films fhaf are clear, fransparent, and odorless Properties Wh. emulsion, si. char, odor 0.1 particle size dens. 9.76 lb/ gal vise. 200-800 cps pH 4.0-6.5 50-52% total solids EverGlide UV-636 [ShamrockTech.]... 

However, there is practically no research work pubUshed focussing on the preparation of kraft lignin-PF hybrid resins for the impregnation of papers intended for decorative laminates. Here, typically resol PF resins of low viscosity and rapid curing characteristics are applied. Kraft papers are impregnated with PF and stacks of such papers are cured in a press at elevated temperature to form cured panel products that are preferably used as exterior claddings and in kitchen and bathroom surfaces where high moisture resistance is required. 

An unaccelerated orthophthalic resin of good transparency and flexibility for the continuous impregnation of paper. 

A composite comprising paper and a conducting polymer can be prepared by impregnation of paper with a solution of a precursor polymer and heat treating the coated paper. The electrically conducting polymer is located on the surface or between the fibers of the paper [885]. Sexithiophene and other oligo(thiophene)s are ideal photochromic materials for efficient and ultrafast incoherent-to-coherent optical converters [886]. 

Gaseous impregnation of paper and books with an EA/MMA mixture followed by gamma-irradiation was proposed for the strengthening of paper in bulk (Burstall et al., 1986) but the idea has not been developed. 

Impregnation of paper Cut strips of chromatographic paper, about 15 cm wide and 55 cm long, saturate with a 40 per cent v/v solution of formamide in methanol and dry without the aid of heat. 

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