Color changes of various wood species in response to moisture

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F62156489%3A43410%2F19%3A43915538" target="_blank" >RIV/62156489:43410/19:43915538 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.22382/wfs-2019-014" target="_blank" >https://doi.org/10.22382/wfs-2019-014</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.22382/wfs-2019-014" target="_blank" >10.22382/wfs-2019-014</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Color changes of various wood species in response to moisture

Popis výsledku v původním jazyce

Color including texture and gloss is one of the most important esthetical attributes of wood. For any porous materials in contact with water, the phenomenon of surface darkening arises from a change in the refractive index, as water enters air-filled pores. For the first time, this research investigated to what extent MC differences affect the surface color, below fiber saturation and after the pores are filled with water, with respect to extractive contents. Samples from 13 wood species were exposed to various climates, and as soon as EMC was reached, the color was determined. Color changes were also recorded after water submersion and also after vacuum impregnation in water. Chromaticity parameters a* and b* widely increased, along with higher moisture contents. Lightness changesweremostly stable at lower moisture contents.An exceptionwas demonstrated by the heartwood species black locust, plum, walnut, and oak, which showed a brightening effect at lowermoisture contents, followed by the darkening phase. The overall darkening of wood at high RH is connected to capillary condensation. Liquid water present in the cell lumen most caused darkening and an intensification of hue (increase in a* and b*). Darkening was even more expressed after vacuum impregnation with water. In conclusion, with only limited fluctuations in moisture contents below fiber saturation, the expected color changes are minor to neglectabl.

Název v anglickém jazyce

Color changes of various wood species in response to moisture

Popis výsledku anglicky

Color including texture and gloss is one of the most important esthetical attributes of wood. For any porous materials in contact with water, the phenomenon of surface darkening arises from a change in the refractive index, as water enters air-filled pores. For the first time, this research investigated to what extent MC differences affect the surface color, below fiber saturation and after the pores are filled with water, with respect to extractive contents. Samples from 13 wood species were exposed to various climates, and as soon as EMC was reached, the color was determined. Color changes were also recorded after water submersion and also after vacuum impregnation in water. Chromaticity parameters a* and b* widely increased, along with higher moisture contents. Lightness changesweremostly stable at lower moisture contents.An exceptionwas demonstrated by the heartwood species black locust, plum, walnut, and oak, which showed a brightening effect at lowermoisture contents, followed by the darkening phase. The overall darkening of wood at high RH is connected to capillary condensation. Liquid water present in the cell lumen most caused darkening and an intensification of hue (increase in a* and b*). Darkening was even more expressed after vacuum impregnation with water. In conclusion, with only limited fluctuations in moisture contents below fiber saturation, the expected color changes are minor to neglectabl.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20502 - Paper and wood

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Wood and Fiber Science

ISSN

0735-6161

e-ISSN

—

Svazek periodika

51

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

13

Strana od-do

119-131

Kód UT WoS článku

000478040900002

EID výsledku v databázi Scopus

2-s2.0-85083028438