Abstract: Provided are a rinsing agent to produce a hard disk substrate free from remaining abrasive grains as well as a pit defect on the surface thereof and a method for production of a hard disk substrate using such a rinsing agent. A rinsing agent of the present invention is rinsing solution containing colloidal silica as abrasive grains. Letting that the colloidal silica abrasive grains have a concentration C and an average grain size R (C and R are represented in weight % and nm, respectively), the concentration C and the average grain size R of the colloidal silica abrasive grains have a relation matching the following Expression (1): 12.2C+18.2??(1).

Abstract: Provided are a rinsing agent to produce a hard disk substrate free from remaining abrasive grains as well as a pit defect on the surface thereof and a method for production of a hard disk substrate using such a rinsing agent. A rinsing agent of the present invention is rinsing solution containing colloidal silica as abrasive grains. Letting that the colloidal silica abrasive grains have a concentration C and an average grain size R (C and R are represented in weight % and nm, respectively), the concentration C and the average grain size R of the colloidal silica abrasive grains have a relation matching the following Expression (1): 12.2C+18.2 (1).

Abstract: This invention intends to provide a long life member for air motors (rotor cylinder material, front cylinder cover material, rear cylinder cover material or the like) having more greater and uniform Vickers hardness than usual and excellent in abrasion resistance, shock resistance and thermal impact resistance. For this purpose, in this invention, a contact surface of a vane-surrounding member with vanes is heated at 450 to 580° C. in the mixed gas atmosphere comprising 50 to 95% of hydrogen, and 5-50% of nitrogen and 0.01 to 99 parts by volume of hydrogen sulfide based on 100 parts by volume of nitrogen, a DC voltage at 300 to 500 V is applied relative to an anode disposed in a vacuum chamber and a nitrosulphurization layer having mean value for the Vickers hardness of 800 to 1200 with a larger difference between the mean value and the maximum value or the minimum value being 100 or less, is formed on the surface of contact with the vanes by using a bright nitrogen diffusion method.

Abstract: The object of the present invention is to provide a packaging apparatus that supplies the packaging material by the packing material supply means provided independently of the mobile body that moves along the annular guide body. In order to achieve the object, the packaging apparatus of the present invention comprises a mobile body for leading a packaging material, an annular guide body for guiding said mobile body along said annular guide body, mobile body drive means for moving the mobile body along the annular guide body, and packaging material supply means disposed outside said annular guide body.

Abstract: A tool for tightening and melt-adhering a strap, which is light in weight, can be operated by one hand, performs a series of operations, i.e., tightening, pressurizing and frictionally melt-adhering the strap by utilizing power (fluid pressure) instead of manual operation, and which enables the time for frictional melt-adhesion to be adjusted over a wide range and highly precisely with ease, enabling the worker to continue the operation maintaining high efficiency with less fatigue. The tool for tightening and melt-adhering the strap comprises a means for pressing a tightening roller which includes a reversible motor, a means for pressing a vibrator for friction, and a timing mechanism capable of adjusting the time for driving the vibrator over a wide range and finely, which are compactly arranged as a unitary structure.