| 摘要 |
<p>1,116,552. Corrugated paperboard. SUN OIL CO. 25 April, 1966 [21 July, 1965], No. 18041/66. Heading B5N. Corrugated paperboard is produced by contacting at 138‹ to 177‹ C. a corrugated paper medium and a hot melt adhesive which has a Brookfield viscosity of 15 to to x 10<SP>3</SP> centipoise in this temperature range, the hot melt adhesive being at a higher temperature than the corrugated paper, and contacting the corrugated paper bearing adhesive with kraft paper liner. Single-faced or double-faced corrugated board may be produced, as may two- or three-layer board. Suitable adhesives are polypropylene, a formaldehyde-aromatic hydrocarbon resin, ethylene-vinyl acetate copolymer and styrenebutadiene rubber. A suitable apparatus (Fig. 1) comprises a pair of corrugating rolls 1, 2, a guide 7 to hold the paper 10 on these, and a coating roll 4 passing through a pan of adhesive 15 and subsequently a doctor roll 5 and/or blade 6, thereby coating the flutes of the corrugated paper, and finally a roller 3 bearing the substrate 11 used for facing. In a modified apparatus the adhesive is applied directly from a heated resin pan using a metering device.</p> |
