Optical Evaluation of Resin Coverage on Fiber Furnish


  • Ronnie O. Albritton
  • Paul H. Short
  • Duane E. Lyon


Medium-density fiberboard, fiberboard, hardboard, resin coverage, resin level, blender loading rate, short-retention-time blender, rhodamine B


This study describes an inexpensive and simple method of evaluating the percent of surface area of fiberized wood furnish that is covered with adhesive. The method uses an integrating microscope eyepiece and a random-field sampling technique to observe dyed (rhodamine B) resin. Blended furnishes of known surface coverages were evaluated to illustrate the accuracy of the sampling technique. The technique is particularly adaptable to in-plant use. The relationship between resin coverage, resin level, and blender loading rate is presented. Results indicate that, on a surface area basis, smaller size fiber does not receive a disproportionate share of resin when blended in a pilot-plant-size, short-retention-time blender.


Campbell, C. C. 1974. An in-plant study of two types of particleboard resin blenders. Eighth Particleboard Symposium Proceedings, Washington State Univ., Pullman, WA. Pp. 199-218.nGinzel, W., and G. Stegmann. 1970. Subsequent dyeing of urea-formaldehyde resin binders on glued wood chips for visual estimation of glue distribution. Holz Roh-Werkst. 28(8): 289-292.nHaigh, A. H., Jr., and H. J. Zahhnt. 1967. The Bison blenders. First Particleboard Symposium Proceedings, Washington State Univ., Pullman, WA. Pp. 275-289.nHarris, J. M. 1969. Use of beta rays in determining wood properties. Part 4: Estimating the thickness of tracheid cell walls. New Zealand. J. Science 12(2):432-442.nLehmann, W. F. 1965. Improved particleboard through better resin efficiency. For. Prod. J. 15(4): 155-161.nLehmann, W. F. 1968. Resin distribution in flakeboard shown by ultraviolet light photography. For. Prod. J. 18(10):32-34.nLehmann, W. F. 1970. Resin efficiency in particleboard as influenced by density, atomization, and resin content. For. Prod. J. 20 (11) :48-53.nMaloney, T. M. 1975. Use of short-retention-time blenders with large flake furnishes. For. Prod. J. 25(5):21-29.nNeuer, H. 1967. Quantitative analysis with the microscope. Zeiss Information No. 60:1-5.nQuirk, J. T. 1975. Dot-grid integrating eyepiece: two techniques for estimating cell wall area. Wood Sci. 8(2):88-91.nQuirk, J. T., and D. Smith. 1975. Comparison of dual linear and dot-grid eyepiece methods for estimating wood properties of Douglas-fir. Wood Sci. 8(2):92-96.nTaylor, F. W. 1973. Variations in the anatomical properties of South African grown Eucalyptus grandis. Appita 27(3): 171-177.n






Research Contributions