Abstract The invention provides a novel means for the improvement of the surface properties of a gramophone record made of a vinyl chloride-based resin which is deficient in respect of the susceptibility to electrostatic charging and anti-wearing resistance with consequent noise generation in the playing of the record. The inventive method comprises irradiating the surface of the gramophone record with ultraviolet light having a substantial energy distribution in the wavelength region of 200 nm or shorter in an atmosphere of oxygen or an oxygen-containing gaseous mixture of which the pressure or partial pressure of oxygen is at least 15 Torr. The effect of the ultraviolet irradiation is further enhanced and the durability of the antistatic effect is increased by bringing the ultraviolet-irradiated surface of the gramophone record into contact with a solution containing a surface active agent followed by washing with water and drying.
A method for the improvement of the surface properties of a gramophone record made of a vinyl chloride-based resin which comprises the step of irradiating the surface with ultraviolet light having a substantial energy distribution in the wavelength region of 200 nm or shorter in an atmosphere of oxygen or an oxygen-containing gaseous mixture of which the pressure or partial pressure of oxygen is at least 15 Torr.
Claim 2
Independent Claim
68 words
A method for the improvement of the surface properties of a gramophone record made of a vinyl chloride-based resin which comprises the step of irradiating the surface with ultraviolet light having a substantial energy distribution in the wavelength region of 200 nm or shorter in an atmosphere of oxygen or an oxygen-containing gaseous mixture of which the pressure or partial pressure of oxygen is at least 15 Torr.
Claim 3
Independent Claim
91 words
A method for the improvement of the surface properties of a gramophone record made of a vinyl chloride-based resin which comprises the steps of (a) irradiating the surface with ultraviolet light having a substantial energy distribution in the wavelength region of 200 nm or shorter in an atmosphere of oxygen or an oxygen-containing gaseous mixture of which the pressure or partial pressure of oxygen is at least 15 Torr, and (b) bringing the surface thus irradiated with ultraviolet light into contact with a solution containing a surface active agent and drying.
Claim 4
Independent Claim
91 words
A method for the improvement of the surface properties of a gramophone record made of a vinyl chloride-based resin which comprises the steps of (a) irradiating the surface with ultraviolet light having a substantial energy distribution in the wavelength region of 200 nm or shorter in an atmosphere of oxygen or an oxygen-containing gaseous mixture of which the pressure or partial pressure of oxygen is at least 15 Torr, and (b) bringing the surface thus irradiated with ultraviolet light into contact with a solution containing a surface active agent and drying.
Claim 5
Dependent Claim
26 words
The method as claimed in claim 1 or claim 2 wherein the pressure or partial pressure of oxygen in the atmosphere is at least 50 Torr.