Spectroscopic monitoring of resin-application prior to assembly of composite wood veneer product

摘要

Disclosed is a method for calibrating electromagnetic (EM) radiation spectroscopic instrumentation so as to enable quantitative analyses of curable resin, as applied to a substantially planar veneer-wood sheet surface area during in-line movement of the sheet, comprising: (A) providing spectroscopic instrumentation enabling wavelengths of EM radiation in a range of about 350 nm to about 2500 nm; (B) quantitatively pre-establishing surface application of said resin, at a selected level of weight per specified surface area, for individual reference wood-veneer test samples; (C) supporting said test samples for movement on a conveyance; (D) positioning the spectroscopic instrumentation in a range of wavelengths including wavelengths absorbed by said resin and capable of penetrating wood-veneer of said test samples; (E) controlling rate of movement of said test samples with respect to said instrumentation, and coordinating said rate of movement with a selected in-line controlled rate of movement for lay-up of veneer wood plies; (F) illuminating a predetermined surface area of said pre-established resin application of said test samples with visible light (VIS) and simultaneously irradiating with near infra-red (NIR), during said conveyed movement of said test samples relative to said instrumentation, and (G) quantitatively measuring radiation absorbance by the test samples during said controlled rate of movement with respect to said instrumentation. Also disclosed is a method for quantitatively monitoring curable-adhesive resin as applied on-line to a selected surface area of a veneer-wood sheet, comprising (A) conveying veneer-wood sheets in-line, presenting a pair of substantially planar opposed surface areas intermediate sheet lateral edges, subsequent to application of said resin; (B) applying said resin by a width-wise application across a substantially planar surface area of a wood-veneer sheet, which is (i) substantially co-extensive width-wise with said applicator width; and, in which (ii) said surface area of resin application is extended longitudinally by travel in-line of said sheets toward said lay-up assembly; (C) selecting placement of calibrated spectroscopic instrumentation for selective monitoring of resin application; (D) selecting EM radiation wavelengths having a peak absorbance by said applied resin; (E) irradiating said selected wavelengths across said portion of resin-applied surface area of said sheet during said travel of said sheets; (F) sensing radiation absorbance of said selected wavelengths by quantitatively measuring reflected-back radiation by wood matrix of said conveyed wood-veneer sheet, and (G) monitoring average resin application weight as applied across said portion of said sheet surface area, while said sheets are moving in-line toward multiple-ply bundle assembly.