Classification of fluorescent whitening agents
1. Classification according to the use of fluorescent whitening agents
(1) Fluorescent whitening agent for textiles. According to the applicable fiber fabrics, fluorescent whitening agents for textiles can be divided into fluorescent whitening agents for cotton, fluorescent whitening agents for protein fibers, fluorescent whitening agents for polyester, fluorescent whitening agents for nylon, and fluorescent whitening agents for viscose fibers. Whitening agent, fluorescent whitening agent for vinylon, fluorescent whitening agent for acetate fiber, fluorescent whitening agent for acrylic fiber, fluorescent whitening agent for printing, etc.
(2) Fluorescent whitening agent for non-textiles. According to their application fields, fluorescent whitening agents for non-textiles can be divided into fluorescent whitening agents for papermaking, fluorescent whitening agents for detergents, fluorescent whitening agents for plastics, fluorescent whitening agents for coatings (paints), and tanning. Use fluorescent whitening agents, fluorescent whitening agents for anti-counterfeiting technology, fluorescent whitening agents for powder whitening, fluorescent whitening agents for pesticides, and fluorescent whitening agents for other fields.
2. Classification according to the structure of fluorescent whitening agents
It is a classification method based on the basic structural type or group of optical brighteners.
(1) DSD acid fluorescent whitening agent. This type of fluorescent whitening agent can be divided into DSD acid bistriazine type fluorescent whitening agent, DSD acid amide type fluorescent whitening agent, DSD acid triazole type fluorescent whitening agent and other types.
(2) Stilrene-based fluorescent whitening agent. This type of fluorescent whitening agent is further divided into stilbene-biphenyl fluorescent whitening agents, stilbene-benzene fluorescent whitening agents, stilbene monotriazole fluorescent whitening agents, etc.
(3) Benzazole fluorescent whitening agents. This type of fluorescent whitening agent is further divided into asymmetric benzoxazole fluorescent whitening agents and symmetrical benzoxazole fluorescent whitening agents.
(4) Benzimidazole fluorescent whitening agents.
(5) Coumarin-based fluorescent whitening agents. This type of fluorescent whitening agent is further divided into 3-phenyl (heterocyclyl) 7-substituted aminocoumarin-based fluorescent whitening agent, 4-methyl 7-substituted aminocoumarin-based fluorescent whitening agent, and 3-carboxylate coumarin. Cationic fluorescent whitening agents and cationic coumarin fluorescent whitening agents.
(6) Naphthalimide fluorescent whitening agent.
(7) Pyrazoline fluorescent whitening agents.
(8) Polymeric fluorescent whitening agent.
(9) Other types of fluorescent whitening agents.
3. Classification according to the ion type of optical brighteners
If classified according to the ionic type of fluorescent whitening agents, they can be divided into anionic fluorescent whitening agents with water-soluble groups such as sulfonic acid groups, cationic fluorescent whitening agents with water-soluble groups such as quaternary ammonium groups, and those that are difficult to dissolve in Three types of water-based non-ionic fluorescent whitening agents.
4. Classification according to whether the fluorescent whitening agent is water-soluble
If fluorescent whitening agents are classified according to whether they are water-soluble, fluorescent whitening agents can be divided into two major categories: water-soluble fluorescent whitening agents and water-insoluble fluorescent whitening agents.
5. Classification according to the use method of optical brighteners
(1) Direct fluorescent whitening agents: Direct fluorescent whitening agents refer to some water-soluble fluorescent whitening agents, and their use is similar to direct dyes.
(2) Dispersed fluorescent whitening agents: Dispersed fluorescent whitening agents refer to some water-insoluble fluorescent whitening agents, and their use is similar to disperse dyes.
6. Classification by series
According to the principle of dye classification in GB/T 6686-1986, the classification of dyes is based on the application method and performance of the dye, and the categories are divided into series. As a kind of white dye, fluorescent whitening agent is mainly used in textile, papermaking, plastics and other industries, and is divided into A, C, D and W series.
A series refers to fluorescent whitening agents that can dissociate into cations in aqueous solution and are suitable for whitening acrylic fibers.
C series fluorescent whitening agents are suitable for whitening cellulose fibers.
D series refers to a type of fluorescent whitening agent dispersed in the dye bath in the presence of dispersant, suitable for whitening polyester and other hydrophobic fibers.
W series refers to fluorescent whitening agents suitable for protein fibers and nylon.
