{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T08:53:14Z","timestamp":1791363194297,"version":"4.3.1"},"reference-count":26,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:00:00Z","timestamp":1791331200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T00:00:00Z","timestamp":1791331200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>A polyurethane acrylate-based photosensitive resin system was developed for 405 nm DLP printing. The formulations were prepared by blending commercial urethane acrylate RT75A with TPO-L, BBOT, and one of four reactive diluents (ACMO, IBOMA, TPGDA, or CTFA). Double-bond conversion was determined by ATR-FTIR, whereas viscosity, UV\u2013Vis transmittance, working-curve parameters (critical exposure and penetration depth), volumetric shrinkage, and mechanical properties were evaluated. The reactive diluent markedly affected both the liquid-state behavior of the resin formulations and the properties of the cured networks. RT75A-TP showed the highest double-bond conversion (97.9%) and volumetric shrinkage (4.65%). RT75A-CT exhibited the highest viscosity at 25 \u00b0C and the largest elongation at break (119 \u00b1 9.5%). RT75A-IB exhibited the highest tensile strength (43.3 \u00b1 3.1 MPa) and flexural strength (57.8 \u00b1 1.1 MPa). All formulations maintained transmittance above 80% from 450 to 800 nm. A transparent aligner with a nominal thickness of 0.55 mm was directly printed from RT75A-IB, and its dimensional accuracy was evaluated by 3D scanning. Overall, the results show that reactive-diluent selection enables the coordinated tuning of DLP processability, double-bond conversion, optical performance, and mechanical behavior.<\/jats:p>","DOI":"10.3390\/ma19194241","type":"journal-article","created":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T08:28:57Z","timestamp":1791361737000},"page":"4241","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Study on Photocuring Printing Technology of Polyurethane Acrylate-Based Transparent Braces"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-0653-9784","authenticated-orcid":false,"given":"Fenglian","family":"Zhong","sequence":"first","affiliation":[{"name":"School of Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, China"},{"name":"Riton Additive Technology Co., Ltd., Guangzhou 510378, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"conceptualization","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Qian","family":"Jiang","sequence":"additional","affiliation":[{"name":"School of Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Liang","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"}]},{"given":"Miaoning","family":"Yan","sequence":"additional","affiliation":[{"name":"Riton Additive Technology Co., Ltd., Guangzhou 510378, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"}]},{"given":"Qingmao","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"supervision","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10212","DOI":"10.1021\/acs.chemrev.7b00074","article-title":"Polymers for 3D Printing and Customized Additive Manufacturing","volume":"117","author":"Ligon","year":"2017","journal-title":"Chem. 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