Research Article

Optical evaluation of the two-sidedness of bleached kraft papers after sunlight exposure

Number: 12 June 23, 2026
EN TR

Optical evaluation of the two-sidedness of bleached kraft papers after sunlight exposure

Abstract

Background and Aims To evaluate sunlight-induced surface color changes in commercially available writing papers using CIE XYZ tristimulus values, whiteness (CIE WI), and yellowness (ASTM E313). Methods Paper samples were exposed to natural sunlight for 15, 30, and 45 days. Surface color was measured using CIE XYZ (1931) values, and whiteness and yellowness indices were calculated. Measurements were performed separately on the felt and wire sides and compared with control samples. Results X and Y values showed only minor changes (<±5 units). Differences between the felt and wire sides also remained below this threshold and were therefore considered negligible. In contrast, Z values decreased significantly with exposure (e.g., from 102.77 to 70.50). Whiteness declined over time, with the highest reduction observed in sample A (76.41%) and the lowest in sample E (12.1%). Yellowness increased notably, particularly in sample A (212.82%). Conclusions Sunlight strongly affected Z values, indicating high sensitivity of the blue color components. This behavior may be associated with photodegradation mechanisms such as the degradation of optical brightening agents (OBAs) and the formation of lignin-related chromophores under UV exposure. Whiteness decreased and yellowness increased with exposure, while differences between the felt and wire sides remained minimal. Sample A showed the lowest resistance to photodegradation.

Keywords

References

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Details

Primary Language

English

Subjects

Forestry Sciences (Other)

Journal Section

Research Article

Publication Date

June 23, 2026

Submission Date

April 15, 2026

Acceptance Date

May 24, 2026

Published in Issue

Year 2026 Number: 12

APA
Şahin, H. T., Cengiz Önal, M., & Özkan, U. (2026). Optical evaluation of the two-sidedness of bleached kraft papers after sunlight exposure. Anadolu Orman Araştırmaları Dergisi, 12, 1931199. https://doi.org/10.53516/ajfr.1931199
AMA
1.Şahin HT, Cengiz Önal M, Özkan U. Optical evaluation of the two-sidedness of bleached kraft papers after sunlight exposure. AJFR. 2026;(12):1931199. doi:10.53516/ajfr.1931199
Chicago
Şahin, Halil Turgut, Meltem Cengiz Önal, and Uğur Özkan. 2026. “Optical Evaluation of the Two-Sidedness of Bleached Kraft Papers After Sunlight Exposure”. Anadolu Orman Araştırmaları Dergisi, nos. 12: 1931199. https://doi.org/10.53516/ajfr.1931199.
EndNote
Şahin HT, Cengiz Önal M, Özkan U (June 1, 2026) Optical evaluation of the two-sidedness of bleached kraft papers after sunlight exposure. Anadolu Orman Araştırmaları Dergisi 12 1931199.
IEEE
[1]H. T. Şahin, M. Cengiz Önal, and U. Özkan, “Optical evaluation of the two-sidedness of bleached kraft papers after sunlight exposure”, AJFR, no. 12, p. 1931199, June 2026, doi: 10.53516/ajfr.1931199.
ISNAD
Şahin, Halil Turgut - Cengiz Önal, Meltem - Özkan, Uğur. “Optical Evaluation of the Two-Sidedness of Bleached Kraft Papers After Sunlight Exposure”. Anadolu Orman Araştırmaları Dergisi. 12 (June 1, 2026): 1931199. https://doi.org/10.53516/ajfr.1931199.
JAMA
1.Şahin HT, Cengiz Önal M, Özkan U. Optical evaluation of the two-sidedness of bleached kraft papers after sunlight exposure. AJFR. 2026;:1931199.
MLA
Şahin, Halil Turgut, et al. “Optical Evaluation of the Two-Sidedness of Bleached Kraft Papers After Sunlight Exposure”. Anadolu Orman Araştırmaları Dergisi, no. 12, June 2026, p. 1931199, doi:10.53516/ajfr.1931199.
Vancouver
1.Halil Turgut Şahin, Meltem Cengiz Önal, Uğur Özkan. Optical evaluation of the two-sidedness of bleached kraft papers after sunlight exposure. AJFR. 2026 Jun. 1;(12):1931199. doi:10.53516/ajfr.1931199