Sterilization method

• US 4,448,750 A
• Filed: 05/23/1983
• Issued: 05/15/1984
• Est. Priority Date: 06/05/1981
• Status: Expired due to Fees

• Current Assignee: Michael L. Fuesting
• Original Assignee: Michael L. Fuesting
• Inventors: Fuesting, Michael L.
• Primary Examiner(s): Lacey, David L.
• Application Number:
  US06/495,922
• Time in Patent Office: 358 Days
• Field of Search: 422/20, 422/24, 422/28, 422/186, 422/292, 422/300, 422/36, 422/37, 134/1, 134/25.4, 134/85, 250/455.1
• US Class Current: 422/20
• CPC Class Codes: A61C 19/002 Cleaning devices specially adapted for dental instruments disinfecting A61L2/00; cleaning in general B08B
• CPC Class Codes: A61L 2/025 Ultrasonics
• CPC Class Codes: A61L 2/035 Electrolysis
• CPC Class Codes: A61L 2/08 Radiation
• CPC Class Codes: A61L 2/10 Ultraviolet radiation
• CPC Class Codes: A61L 2/18 Liquid substances or solutions comprising solids or dissolved gases

Abstract

A method for disinfecting and/or sterilizing small objects such as medical and dental instruments and the like wherein the object to be disinfected and/or sterilized is contacted with a liquid, such as an aqueous solution of sodium dodecyl sulfate and carbamide, which is substantially transparent to ultraviolet radiation and has some bactericidal activity itself, at a temperature in the range from about 0° C. to about 100° C. and preferably at about 25° C., and the object while contacted by the liquid is exposed simultaneously to ultrasonic radiation having a frequency in the range from about 8 kilohertz to about 300 kilohertz, preferably from 15 kilohertz to 60 kilohertz, with an energy density of application from about 10 watts/liter to about 5 watts/milliliter, and to ultraviolet radiation having a wavelength in the range from about 1500 Å to about 4000 Å, preferably at about 2537 Å.

Claims

1. A batchwise and static method of disinfecting and/or sterilizing small objects such as medical and dental instruments and the like comprising the steps of:

(a) contacting an object to be disinfected and/or sterilized with a stationary body of liquid or liquid solution which has a percent transmittance greater than twenty percent to ultraviolet radiation;

(b) exposing said object while contacted by said liquid to ultrasonic radiation;

(c) exposing said object while contacted by said liquid to ultraviolet radiation;

(d) said steps of exposing said object to ultrasonic radiation, ultraviolet radiation and liquid being performed simultaneously; and

(e) said liquid being relatively chemically stable at the temperature employed and under the ultraviolet and ultrasonic energy conditions employed.

2. The method of claim 1, wherein said ultrasonic radiation has a frequency in the range from about 8 kilohertz to about 300 kilohertz.

3. The method of claim 1, wherein said ultrasonic radiation has a frequency in the range from about 15 kilohertz to about 60 kilohertz.

4. The method of claim 1, when said ultrasonic energy is applied to said liquid at a density in the range from about 10 watts/liter to about 5 watts/milliliter.

5. The method of claim 1, wherein said ultraviolet radiation has a wavelength in the range from about 150 nanometers to about 400 nanometers.

6. The method of claim 1, wherein said ultraviolet radiation has a wavelength of about 254 nanometers.

7. The method of claim 1, wherein said liquid has a temperature in the range from about 0°

C. to about 100°

C.

8. The method of claim 1, wherein said liquid has a temperature of about 25°

C.

9. The method of claim 1, wherein said liquid has bactericidal activity.

10. The method of claim 1, wherein said liquid contains a wetting agent to reduce surface tension and promote cleaning action.

11. The method of claim 1, wherein said liquid is an aqueous solution of sodium dodecyl sulfate and carbamide.

12. A batchwise and static method of disinfecting and/or sterilizing small objects such as medical and dental instruments and the like comprising the steps of:

(a) contacting an object to be disinfected and/or sterilized with a stationary body of liquid or liquid solution having a temperature in the range from about 0°

C. to about 100°

C., having a percent transmittance greater than seventy percent to ultraviolet radiation, and having bactericidal activity;

(b) exposing said object while contacted by said liquid to ultrasonic radiation having a frequency in the range from about 8 kilohertz to about 300 kilohertz and applied to said liquid at a density in the range from about 10 watts/liter to about 5 watts/milliliter;

(c) exposing said object while contacted by said liquid to ultraviolet radiation having a wavelength in the range from about 150 nanometers to about 400 nanometers;

(d) said steps of exposing said objects to ultrasonic radiation, ultraviolet radiation and liquid being performed simultaneously; and

(e) said liquid being relatively chemically stable at the temperature employed and under the ultraviolet and ultrasonic energy conditions employed.