Adhesive with anisotropic electrical conductivity and methods of producing and using same
AssigneeTuTech Innoovation GmbH
InventorSamuel Buschhorn
Life of this patent
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Abstract
The invention relates to an electrically conductive adhesive, comprising an adhesively acting, curable and electrically non-conductive matrix material and a phase of electrically conductive carbon nanotubes distributed in the matrix material. According to the invention, the carbon nanotubes are present in a plurality of individual macrostructures, and each macrostructure consists of a plurality of agglomerated carbon nanotubes forming and electrical contact among each other. Another aspect of the invention concerns a method of producing such an electrically conductive adhesive, and a method for electrically conductive bonding of two components and for checking the quality of an adhesive bond formed in such a manner.
Claims18
An electrically conductive adhesive, comprising
- an adhesively acting and electrically non-conductive or weakly conductive matrix material (6;
- 41), preferably of a polymer material or a polymerisable material, and
- a phase of electrically conductive carbon nanotubes (1) distributed in the matrix material,
- characterised in that the carbon nanotubes are present in a plurality of individual macrostructures (40a-c;
- 140a-c;
- 5), that each macrostructure consists of a plurality of agglomerated carbon nanotubes forming electrical contact among each other, and that the macrostructures are present in the matrix material in a concentration that is lower than the percolation threshold of the macrostructures within the matrix material.
A method of producing an electrically conductive adhesive, comprising the steps of
- a. supplying an auxiliary production matrix (2),
- b. introducing carbon nanotubes (1) into the auxiliary production matrix,
- c. agglomerating the carbon nanotubes to form macrostructures (5) within the auxiliary production matrix, and
- d. distributing the macrostructures in a polymeric adhesive matrix (6) in a concentration below the percolation threshold of the macrostructures in the adhesive mass.
A method for electrically conductive bonding of two components (10, 20), the method comprising the steps of
- a. supplying an adhesive (41, 40a,b,c), comprising an adhesive matrix (41) formed from an adhesively acting material and a plurality of carbon nanotubes,
- b. introducing the adhesive into at least one joining surface (21) of one of the two components to be joined,
- c. joining the two component in such a way that the joining surface (11) of the one component is placed onto the joining surface (21) of the other component and an adhesive gap (30) forms between these two joining surfaces,
- wherein the thickness (s) of the adhesive gap, at least in those sections of the adhesive gap lying between two opposite regions of the joining surface, between which an electrically conductive connection is to be produced from the joining surface region of the one component across the adhesive gap section to the joining surface region of the other component, is less than or equal to a dimension (D) of a macrostructure (40a,b,c) which is formed of a plurality of the carbon nanotubes and is present in the adhesive matrix (41),
- d. forming an electrical connection by means of carbon nanotube macrostructures in sections of the adhesive gap lying between regions of the joining surface that have electrically conductive regions of the joining surface regions (11a-c, 21a-c) facing towards the adhesive gap and towards each other, and which are to be electrically connected to each other via said regions,
- e. curing of the matrix material.
Dependencies are inferred from the claim text.