Compare Cotton & Paper OBA, Detergent & Soap OBA, Paper & Pulp OBA, and Textiles & Cotton OBA. Learn how CI number, EV value, substrate, and process chemistry guide OBA selection.
Optical Brightening Agents (OBA), also called fluorescent whitening agents, improve perceived whiteness by absorbing ultraviolet light and re-emitting blue-violet light. The correct grade depends on substrate, process temperature, pH, ionic character, dosage, and the whiteness or tone required by the finished product. Chem Horizons supplies OBA grades for cotton, paper, pulp, detergents, soap, and textile applications.
OBA category map
Buyers should begin with the end-use category rather than choosing an optical brightener by trade name alone. The four categories below organize OBA selection by substrate and production route:
- Cotton & Paper OBA for cellulosic fibers, paper surfaces, and general cellulose brightening.
- Detergent & Soap OBA for laundry powders, washing liquids, cleaners, and soap formulations.
- Paper & Pulp OBA for pulp treatment, paper coating, and board brightness.
- Textiles & Cotton OBA for cotton, blended fabrics, and textile finishing baths.
Cotton & Paper OBA
Cotton & Paper OBA serves two closely related cellulose systems: textile fibers and paper substrates. This group includes OBTEX BA-267% at 540-550 EV, OBTEX-BMK at 450-460 EV for a bluer tone, OBTEX-BA-LQ at 125 EV, and additional liquid and powder grades. CI numbers in this group include CI 113, CI 220, CI 220/336, CI 28/85, and related combinations listed for individual grades.
Choose this category when a buyer needs a general cellulose brightener, a paper-compatible grade, or a textile product with a controlled white or tinted tone. Compare the product's EV value, concentration, physical form, and application notes before lab trials. Review Cotton & Paper OBA grades and request TDS/SDS documentation for the selected product.
Detergent & Soap OBA
Detergent & Soap OBA is designed for optical whiteness on fabrics during washing. The brightener must remain compatible with the detergent base, dissolve or disperse correctly in the chosen format, and deposit effectively on textile fibers without being removed during rinsing. The category includes OBTEX-4BK, OBTEX-4BM, concentrated OBTEX-4BM-CONS., OBTEX-DMS-X, OBTEX-DMS-CONS, and OBTEX-CXT-LQ.
Published EV values range from approximately 100 EV for OBTEX-CXT-LQ to 500 EV for concentrated grades. Compare Detergent & Soap OBA products by CI number, EV value, concentration, formulation format, and the washing performance required by the finished detergent.
Paper & Pulp OBA
Paper & Pulp OBA is used to increase the visual brightness of pulp, coated paper, writing paper, packaging board, and related paper products. Paper mills typically evaluate brightness lift, retention, compatibility with sizing and coating chemistry, and performance at the target pH and process temperature.
The catalog includes OBTEX-BBU-250% at 435 EV with CI 220 and OBTEX-ABP-X at 425 EV with CI 220. Browse Paper & Pulp OBA grades and request the matching technical document before a mill trial.
Textiles & Cotton OBA
Textiles & Cotton OBA covers anionic brighteners containing sulphonate groups for cotton, wool, nylon, and blended textile systems. Grades include OBTEX-UBR-LQ, OBTEX-4BK, OBTEX-B2S, OBTEX-2B, concentrated 2B grades, and high-brightness BSU liquid and powder products.
Textile buyers should compare CI number, EV value, tone, concentration, and whether the product is liquid or powder. For example, OBTEX-BSU grades are listed as high-brightness products, while OBTEX-B2S grades are identified as tinted products. Review Textiles & Cotton OBA grades for cotton and blended-fabric finishing requirements.
How to choose an OBA grade
- Identify the substrate: cotton, viscose, wool, nylon, pulp, paper, detergent, or soap.
- Define the process route, including exhaust, pad, coating, pulp addition, liquid detergent, or powder detergent.
- Compare CI number, EV value, shade tone, concentration, and physical form.
- Run a controlled laboratory trial at the target pH, temperature, dosage, and liquor ratio.
- Confirm TDS, SDS, COA, packing, MOQ, and destination-market documentation before bulk supply.
OBA sourcing FAQ
What does EV value mean in an OBA catalog?
EV is a supplier-reported brightness or strength reference used to compare grades within a product range. It should be read together with concentration, test method, CI number, and application conditions rather than treated as a universal cross-supplier performance guarantee.
Can one OBA grade be used for every application?
No. A grade optimized for detergent deposition may not be the right choice for paper coating or textile exhaust. Select by substrate and process, then confirm with a lab trial and technical documentation.
How do I request an OBA quote?
Use the OBA catalog or contact Chem Horizons with substrate, application, target EV or whiteness, monthly volume, packing preference, and destination country.
Related reading: reactive dyes for cotton · pigment paste vs reactive dyes · all OBA products.