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I am a fluorescent whitening agent, this is my resume
发布时间:2016.03.24  浏览次数:
 

In life, the use of fluorescent whitening agent products are many, garments, paper, plastic products and so on. But, few people know what it is the existence of the "magic". So, this article, from the following aspects to let go of it.

1. The introduction of fluorescent whitening agent

2. The classification of fluorescent whitening agent

3. The influence factors of fluorescent whitening agent

A, what is the fluorescent whitening agent?

1. The fluorescent whitening agent: is a kind of fluorescent dye, dye or white, is also a kind of complex organic compounds. It can stimulate the incoming light are the characteristics of fluorescence, make the material stain similar fluorite shimmering effect, make the material of the naked eye is very white, whitening effect.

2. Whitening principle: under the sunlight, it can absorb light in the visible to the naked eye can see ultraviolet light (300-400 nm) wavelength and the molecular excitation, and then return to the ground state, part uv energy disappears, and then converted to a lower amount of LanZiGuang (wavelength of 420-480 nm). In this way, the effect on the amount of reflection LanZiGuang was increased, so as to offset the original object caused by yellow light reflection and more sense of yellow, produce the effect of a dazzling white, on the vision.

Note: whitening of fluorescent whitening agent is a kind of optical brightening complementary role, is not a substitute for chemical bleached fabric real "white".

Second, the classification of fluorescent whitening agent

According to the classification of fluorescent whitening agent matrix, which can be roughly divided into carbon ring, styrene triazine base amino 2, second - class, benzene and styrene pbo, furan, coumarone and benzene and imidazoles, 1, 3 - diphenyl - pyrazole Lin, coumarin, naphthalene imide nine categories and noise etc. The following is to introduce the six categories of them.

1. The carbon ring class

Carbon ring type of fluorescent whitening agent refers to the parent constituent molecules containing heterocyclic, substituent on the mother also does not contain the heterocyclic type of fluorescent whitening agent, composed of carbon ring type fluorescent whitening agent there are three main forms of the parent molecule, namely:

1.1, 4-2 styrene benzene (1, 4 - Distyrylbenzene)

2.4, 4 '- styrene biphenyl (4, 4' - Distyrylbiphenyl)

3.4, 4 '- styrene divinyl 2 (4, 4' - Divinylstilbene)

Cyano replace diphenylethylene benzene has quite high amount of fluorescence when zi chan rate, on the substrate of the whitening effect is very good, especially suitable for use in a plastic resin and synthetic fiber. A typical varieties are: Palanil Brilliant White R

2. Triazine group amino 2 styrene type

Triazine base amino 2 styrene is composed of 4, 4 '- diamino styrene - 2-2, 2' - disulfonic acid (DSD acid) and 3 get together cyanogen chloride condensation product

With the structure type of fluorescent whitening agent is existing in the commercialization of fluorescent whitening agent varieties most, about more than 80% of the fluorescent whitening agent belong to the structure type.

3. Two styrene - three azole nitrogen

Two styrene - three azole nitrogen is two styrene compounds and condensation product of three azole nitrogen compounds, the fluorescent whitening agent come out earlier. Tonal slant green, its disadvantage is that the fluorescence of the fibers of the whitening white degree is not high, has withdrawn from the market.

4. Benzene and pbo class

Benzene and pbo kind of fluorescent whitening agent is on the production after triazine group amino 2 styrene type fluorescent whitening agent, most is a high performance of fluorescent whitening agent. A typical varieties are: Eastobrite OB - 1

5. Furan, coumarone and benzene and imidazoles

Furan, coumarone and benzene and imidazole itself is not of fluorescent whitening agent, but they all constitute the structure unit of fluorescent whitening agent. They, together with other elements (such as PCB) of good performance of fluorescent whitening agent. The combination of furan and PCB in structure similar to the combination of styrene and PCB. Such combinations containing sulfonic acid groups have good solubility in water, especially suitable for whitening of nylon fiber and cellulose fiber

Coumarin of 6.

The chemical structure of coumarin

Coumarin itself has very strong fluorescence, on its four and seven introduced various replace groups can make it has the practical value of fluorescent whitening agent.

Third, some factors influencing the performances of fluorescent whitening agent

1. Before the treatment: the higher the whiteness of raw materials, the whitening effect is better

2. The amount of fluorescent whitening agent: each saturation concentration of fluorescent whitening agent has its specific limits, more than a fixed limit value, not only the whitening effect will not increase and it will appear "yellow" phenomenon, make the whitening into a "yellow". The concentration of fluorescent whitening agent relationship with the whitening effect as shown in the figure below:

Note: can be seen from the curve in the graph: whitening effect of fluorescent whitening agent under saturated value proportional to its concentration and over saturation value, its whitening effect worse instead.

3. The influence of pH value (pH)

Different pH of dye bath will directly affect the fluorescent whitening agent chemical stability and solubility. PH value had a greater influence on the absorbance of ionic type fluorescent whitening agent. Cationic fluorescent whitening agent at pH > 9 absorbance decreased obviously, and anionic fluorescent whitening agent under acid condition absorbance fell sharply.

4. The influence of surfactant

The fluorescent whitening agent solution in ionic adding surface active agent, whitening effect of fluorescent whitening agent. Join with the opposite charge of surfactant, lowers the solution's absorbance, sometimes even lead to the fluorescence quenching effect, to join with charge of surfactants, no or minimal impact

5. The influence of inorganic additives

Some whitening agent when use add salt or sodium sulfate can improve (or control) it on the fiber adsorption rate. Whitening agent in allocation between the dye bath and fabric along with the concentration of inorganic salts in the solution change, increase the concentration of the inorganic salt can improve the dyeing rate of whitening agent.

6. Color adjustment

The fluorescent whitening agent with different auxiliaries application at the same time, its are tonal and additives of different micro. To achieve the same color, if necessary, can be adjusted and trace dye.

Four, the application of fluorescent whitening agent products

In daily life, many products will add some fluorescent whitening agent, used to increase the light effect products.