Agriculture - Raw Materials for Flowable Formulations
Summary of uses
Some liquid agrochemicals are provided in a flowable form.
They are agrochemicals made by dispersing microparticulated active ingredients in water.
When applying such agrochemicals, the active ingredients must remain finely dispersed. However, it is difficult to keep them dispersed alone in water.
Thus, measures to keep them dispersed such as use of a thickener are taken.
KUNIMINE's KUNIPIA and SUMECTON are inorganic thickeners used in many flowable agrochemical formulations to prevent active ingredients from settling.
Mechanism of a thickener
Montmorillonite, which is the main component of bentonite, has a flat plate-shaped crystal structure that is about 1 nm thick and about several hundred nm wide.
In powder state, these crystals are stacked in layers and aggregated. If they are put in water, water molecules are introduced between the layers, which are finally separated into crystals.
Montmorillonite crystals are negatively charged in the surface direction and positively charged in the width direction. Thus, when the clay is finely dispersed as crystals in water, those crystals attract or repel each other to form a house-of-cards structure.
As a result, resistance to shearing force is developed, increasing the viscosity of (thickening) the liquid.
It is difficult to keep active ingredients of agrochemicals dispersed alone. By using KUNIPIA, which is high-purity montmorillonite, or other thickeners, those active ingredients can be kept dispersed.
By adding a small amount of KUNIPIA, which is made by refining montmorillonite, the main component of bentonite, a natural inorganic material, produces a high thickening effect, which is kept stable for a long period of time.
While organic thickeners can be expected to produce a high thickening effect, they may undergo deterioration with aging and a reduction in viscosity, or aggregate to cause segregation of ingredients in the agrochemicals.
KUNIPIA is a completely inorganic thickener and free from these problems. It does not undergo quality deterioration even if exposed to high-temperature (low-temperature) environments repeatedly.
The figure below shows changes in viscosity of KUNIPIA and refined bentonite from another company dispersed in water at different concentrations when they were repeatedly subjected to a severe hot-cold test cycle of heating them at 60°C for 8 hours and then freezing for 16 hours 14 times.
The test results indicate that KUNIPIA is excellent in storage stability.
|KUNIPIA-F||Powder||Refined bentonite||Prevention of settling
|KUNIPIA-G||Scaly form||Refined bentonite||Prevention of settling
|SUMECTON-SA||Powder||Synthetic saponite||Addition of thixotropy|