Using Statistical Methods to Comparatively Analyze the Visual Characteristics of Flattened Bamboo Boards in Different Bamboo Culms

Different flattened bamboo boards will produce different visual effects, which directly determine consumers' preferences. However, their visual characteristics were unknown. To clarify the visual effects of flattened bamboo boards in different bamboo culms, the visual, physical, and psychological quantities were firstly studied using their quantitative color and glossiness measurements, combined with quantitative semantic differential and statistical methods. Key results revealed that the values of lightness L* and blue-yellow index b* from the base to the top of the bamboo culms tended to decrease gradually, while green-red index a* values exhibited an increasing trend, and glossiness G(ZL) (G(ZT)) showed no significant difference. The L* value of bamboo outer layer (30.18) was smaller than that of the outer (61.90) and the inner (68.68), which had an increasing trend from the outside to the inside of the bamboo culm, while the G(ZL) (G(ZT)) values corresponded to 6.07 (4.66), 4.51 (3.12), and 2.77 (2.55), showing an opposite trend. The a* and b* values present a rise-fall tendency. According to visual psychological assessment, the outer was reflected as an "artificial-decorative", "smooth-warm", and "comfort-sophisticated" feeling; the inner had an "artificial-practical", "smooth-warm", and "comfort-sophisticated" sense; the bamboo outer layer had an "nature-practical", "rough-cold", and "sick-primitive" sense. Furthermore, predictive models for visual psychological quantities were constructed. This work provides a theoretical data basis for furniture design and standard materials application of flattened bamboo boards.