Study on optical brightening agent and uses properties of OBA based on color chemistry.

Experiment No: 06

Experiment Name: Study on optical brightening agent and uses properties of OBA based on color chemistry.

Definition : 

Optical brightening agent (OBA) or fluorescent whitening agents (FWA) is added to many substances to reduce yellowing, improve whiteness and enhance the brightness of the fabric/products.

Types of OBA:

There are three different types of OBA/FWA based on the sulfonic group:

(1) DIsulfonic: It constitutes of two sulfonic groups and is good for hydrophobic fiber. Example: Nylon, Silk and polyester.

(2) Tetrasulfonic: It constitutes of four sulfonic groups and having its good solubility.

(3) Hexasulfonic: It constitutes of six sulfonic groups and excellent solubility.

Uses (OBA):

(1) The OBA’s are most widely used in textiles papers, detergent, plastics.

(2) OBA absorbs high energy radiation in the ultra-violent region (330 nm – 480 nm).

(3) Anionic OBA’s exhaust on cotton, wool and silk and cationic OBA’s exhaust on acrylic/polyester and non-anionic exhaust on all synthetics.

Properties (OBA/FWA):

(1) It should have good solubility.

(2) OBA should have good light as well as wash fastness properties.

(3) Build up and exhaustion properties.

(4) Affect of water hardness.

(5) It should have good leveling and penetrating properties.