WDG formulations of the experience of a product component

WDG product benefits will not go into again, and I believe a lot of literature has detailed information on the record, I am here to say that these years I WDG formulations of some of the views during the study. 

WDG mainly by the active ingredient, dispersant, wetting agent, anti-hard agent, disintegrating agent, binders, fillers, such as several parts, and through the ultra-fine powder, the granulation until the finished product. The following sections in this talk about my personal experience. 

1, the dispersing agent 

WDG on the use of dispersants in basically two polycarboxylate salts, naphthalene sulfonate these types of classes and lignin, polycarboxylic acid salts, mainly the domestic application of Huntsman's T-2700, Rhodia's T36, Croda's 550s, made mainly Guangyuan AgroSciences, Han Moke, Nanjing engine auxiliary buildings. Advantages and disadvantages of each of these types of additives, not one by one comment; naphthalene sulfonate class mainly Akzo Nobel's D-425, D-500 as the representative agent; lignin mainly imported Bao Lige and maintenance Real Vick's agent. 

WDG on the selection of dispersant used in the different effects of the original drug is not the same as we did dimethomorph, the use of naphthalene sulfonate dispersing agent class is better than using polycarboxylate dispersant salts; Generation Sen MZ WDG will generally use lignin dispersant; triazine herbicides salts with polycarboxylic acid dispersant great effect. In short according to the actual situation of the choice of dispersant. 

Sometimes the issue of considering the cost, you can add a certain amount of NNO, may be appropriate to reduce the amount of dispersing agent mainly, we generally call the NNO adding dispersant for the help. Should be said that many manufacturers are doing. 

2, wetting agent 

Dispersants are generally manufacturers with a wetting agent, such as T-2700 with T-1004; D-425 with Morwet EFW, made in China but also with the corresponding dispersant effect of wetting agents are relatively good. Here you can choose the number of wetting agents, I have also used in some products on their own some very good wetting agent results in lower costs from the point of view is worth a try. 

3, anti-hard-agent 

WDG in 2006, when I do, kind of ingredients (of course, was using a code name), adding time and without suspension rate when the difference between the larger product, but the selling price of this kind of thing quite expensive, we have been used more than six months. Later we discovered that in fact that something is disodium EDTA. So hard-agent anti-WDG formulations in general constitute an indispensable, now commonly used anti-agent generally have just a few hard-EDTA, EDTA disodium, sodium tripolyphosphate, five sodium tripolyphosphate, crystalline layered sodium disilicate . In fact these things are mainly used in washing powder is also played the role of anti-hard water. This should be the most widely used inside or disodium EDTA and sodium tripolyphosphate. 

4, disintegrating agents 

As the name suggests this component is mainly to improve the product disintegration WDG to join, but I think that the disintegration products influenced by many factors, dispersant, wetting agent, filler, granulation method, extrusion strength, and so will be on Product disintegration performance impact. Disintegrating agents here described only in general use of inorganic salts under more disintegrants, such as sodium sulfate, ammonium sulfate; also use urea as a disintegrating agent. 

According to my understanding of the relevant literature and the mechanism of disintegration agent, is WDG products into the water, disintegrating agents can quickly dissolve, making the particles massive depression, equivalent to increasing the surface area, which play a role in dispersing agent, making the particles quickly disintegration. 

In short, the principle of selection is a disintegrating agent, stable easy to break; 2, has a higher melting point; 3, water solubility; 4, does not react with the active ingredient. 

5, Binder 

General role is to improve the adhesive strength of particles, so broken in storage and transportation is not easy, but this product seems to be contradictions between the collapse of the performance, so in considering the collapse of granular strength and product performance to achieve a balance. I actually know less of the binder, because I do WDG products rarely add binder, half in terms of dispersants and packing products to consider addressing WDG problems forming and particle strength. However, there is a problem need help, in the boiling granulation process may need to add some binder, it can make rapid prototyping, low water, high strength, low energy consumption. 

6, packing 

WDG for the high levels of product choice is not packing, but packing is a good choice. Here I would like to focus on that is for low levels of WDG products, of which 50% or even 80% of the group was divided into filler, so the choice of filler is particularly critical. 

We usually use the filler is generally kaolin, diatomaceous earth, light calcium, talc, bentonite, mica and so on. 

Do filler kaolin suspension rate of product benefits, but if you added too big, likely to cause the material stick, granulation easy to stick together, resulting in disintegration performance. 

Diatomite, on this kind of thing that could cause WDG products into the water, sink to the bottom slow down, if done well, then there will be while sinking half collapse, in the end the basic collapse when completed. We dream of the phenomenon. 

Light calcium light calcium PH as high, so I do not use WDG products, the amount of time too, generally 10% -20%, light calcium disintegration of the product will not play much effect on the suspension rate of not obvious. 

Talc itself than significant, easy to sink to the bottom. On the grain shape is good. Similarly only a small amount to join. 

Bentonite, swelling due to its own nature, so the collapse of WDG products improved significantly, but Cadogan products could result in suspension rate. 

Mica, did not find any characteristics of the product suspension rate of disintegration did not change significantly. The familiar wish to add. 

WDG products for low content, it is generally impossible to use a filler to make good products. Usually have to fill two or more of the match, only familiar with the performance of materials can quickly filter out good formula.