Recently, DSY company has two more invention patents authorized by the State Intellectual Property Office. The patents names are "A Plant Fiber Modified Fungus Powder and Its Preparation Method" and "A High Temperature Resistant and Environmental Friendly Multifunctional Additive for Frilling Fluid and Its Preparation Method". The patent numbers are ZL 2022104554612 and ZL 2022104552212.

The product corresponding to the disclosure of the two invention patents is the alkyl cellulose polysaccharide for drilling fluid DACP which is recently developed by the company R&D center. DACP is a heteroglycan cellulose derivative prepared through alkylation and other processes. DACP has both properties of heteroglycan and cellulose. It is an environmental protection drilling fluid additive with multiple functions of filtration reduction, lubrication, inhibition, rheological property adjustment, etc. And the temperature resistance can reach to 140 ℃, the salt resistance and calcium resistance ability are very strong, and it can be used in CaCl₂ (in different concentrations until saturation) drilling fluid and completion fluid. DACP is an excellent additive for preparing environmental protection and reservoir protection solid free drilling fluid and completion fluid.