Method of transmitting ultrasonic impulses to surface using transducer coupling agent

• US 4,002,221 A
• Filed: 11/15/1974
• Issued: 01/11/1977
• Est. Priority Date: 09/19/1972
• Status: Expired due to Term

• Current Assignee: Gilbert Buchalter
• Original Assignee: Gilbert Buchalter
• Inventors: Buchalter, Gilbert
• Primary Examiner(s): Lovering, Richard D.
• Application Number:
  US05/524,316
• Time in Patent Office: 788 Days
• Field of Search: 128/417, 252/316, 252/500, 252/518, 106/169, 106/170, 73/71.5 US, 204/157.1 S, 181/402, 181/.5
• US Class Current: 181/.5
• CPC Class Codes: A61B 5/259 using conductive adhesive means, e.g. gels
• CPC Class Codes: A61B 5/411 Detecting or monitoring allergy or intolerance reactions to an allergenic agent or substance
• CPC Class Codes: A61N 1/0452 Specially adapted for transcutaneous muscle stimulation [TMS]
• CPC Class Codes: A61N 1/0456 Specially adapted for transcutaneous electrical nerve stimulation [TENS]
• CPC Class Codes: A61N 1/046 Specially adapted for shock therapy, e.g. defibrillation
• CPC Class Codes: A61N 1/0496 characterised by using specific chemical compositions, e.g. hydrogel compositions, adhesives
• CPC Class Codes: G10K 11/02 Mechanical acoustic impedances; Impedance matching, e.g. by horns; Acoustic resonators
• CPC Class Codes: Y10S 181/402 Liquid

Abstract

Gel compositions are disclosed containing a primary thickening agent (e.g. carboxy polymethylene polymer) combined with small but effective amounts of an auxiliary hydroxy-containing thickener, e.g. an hydroxy alkyl cellulose polymer. The gel is particularly suitable for use with transducers wherein the gel is introduced between a transducer element (for example, an electrode) and skin or surface. The gel compositions are advantageous in that they do not irritate the skin, do not corrode the transducer element, are slow to dry and do not substantially leak out from the area of contact. The process of using the gel is also included.

Claims

1. In a method of transmitting ultrasonic impulses to a surface in contact with transducer means with a conductivity gap therebetween, the improvement comprising applying a transducer coupling agent to said conductivity gap formed of a composition consisting essentially of:

about 1/20th of 1 wt% to 10 wt% of a long chain

water soluble ionic polymeric thickener having a Brookfield Viscosity (CPS) of approximately 1000 to 100,000 at 1 wt% concentration in H₂ O and neutralized with an alkaline agent, said thickener being selected from the group consisting of a copolymer of methyl vinyl ether and maleic anhydride, carboxy polymethylene polymer and mixtures thereof,

about 1/1000 of 1 wt% to 3 wt% of a hydroxy alkyl cellulose polymer as an auxiliary thickener,

about 10% to 25% by weight of a polyalkylene glycol humectant, said alkylene group containing 2 to 10 carbon atoms,

up to about 5 wt% of an alkali metal salt of a weak organic acid,

up to about 5 wt% of a weak organic acid,

and the balance essentially water, said gel having a pH of about 3.5 to 11.5.

2. In a method of transmitting ultrasonic impulses to a surface in contact with transducer means with a conductivity gap therebetween, the improvement comprising applying to a transducer coupling agent to said conductivity gap formed of a composition consisting essentially of:

about 1/10 of 1 wt% of 3 wt% of carboxy polymethylene polymer substantially neutralized with an alkaline agent,

about 1/10th of 1 wt% to 3 wt% of hydroxy ethyl cellulose,

about 14% to 22% by weight of propylene glycol,

and the balance essentially water, said gel having a pH of about 5 to 9.5--.

3. The method of claim 2 wherein said energy in pulses is ultrasonic vibrations and wherein said gel composition contains approximately 1/2 of 1 wt% carboxy polymethylene polymer, approximately 1/4 of 1 wt% hydroxy ethyl cellulose, approximately 18 wt% propylene glycol and approximately 40 wt% of sodium hydroxide based on the amount of carboxy methylene polymer present.