Composite tape for use in tape laying machines
View Patent ↗A tape for use in automated tape laying machines that includes a multi-layer substrate composed of a plastic layer that includes at least one plastic film having an outer film surface and an inner film surface. The plastic film is adhered to a fibrous layer so that the inner surface of the fibrous layer is bonded to the inner film surface. An uncured composite material layer composed of a fibrous reinforcement and an uncured resin matrix is releasably adhered to either the plastic layer surface or the outer fiber layer surface to provide a tape suitable for use in an automatic tape layer.
1. A tape in an automated tape laying machine, said tape comprising a sticky uncured composite material layer supported on a substrate wherein said sticky uncured composite material layer is applied to a mold while still supported by said substrate and wherein said substrate is removed from said sticky uncured composite material layer after application of said uncured composite material to said mold, said tape comprising:
1) the sticky uncured composite material layer comprising a fibrous reinforcement and an uncured resin matrix, said uncured composite material layer having a first sticky composite surface that is applied to said mold and a second sticky composite surface that is releasably attached to said substrate;
2) the substrate comprising:
a) a first plastic layer comprising a first plastic film having an outer surface and an inner surface wherein said outer surface of said first plastic film has not been treated with a release agent, said outer surface of said first plastic film being attached to said second sticky composite surface, wherein said first plastic film is a simultaneously oriented polypropylene film wherein the inner surface of said first plastic film is rougher than said outer surface of said first plastic film;
b) a second plastic layer comprising a second plastic film having an inner surface and an outer surface wherein the outer surface of said second plastic film has been treated with a release agent; and
c) a fibrous layer having an outer fiber surface and an inner fiber surface wherein the inner fiber surface is bonded to the inner surface of said first plastic film and said outer fiber surface is bonded to the inner surface of said second plastic film.
2. The tape in an automated tape laying machine according to claim 1 wherein said first plastic film has a cross directional tensile strength that is higher than the cross directional tensile strength of said second plastic film.
3. A roll of tape in an automated tape laying machine, said roll of tape comprising a tape according to claim 1 wherein the outer surface of said second plastic film which has been treated with said release agent contacts said first composite surface of said uncured composite material layer only when said tape is in the form of a roll.
4. The tape in an automated tape laying machine according to claim 1 wherein the inner fiber surface of said fibrous layer is bonded to the inner surface of said first plastic film with an adhesive.
5. The tape in an automated tape laying machine according to claim 4 wherein the outer fiber surface of said fibrous layer is bonded to the inner surface of said second plastic film with an adhesive.
6. The tape in an automated tape laying machine according to claim 1 wherein the outer fiber surface of said fibrous layer is bonded to the inner surface of said second plastic film with an adhesive.
7. The tape in an automated tape laying machine according to claim 1 wherein said second plastic film comprises a second polypropylene film.
8. The tape in an automated tape laying machine according to claim 7 wherein said second polypropylene film is a blown-extruded polypropylene film wherein the inner surface of said second plastic film is rougher than said outer surface of said second plastic film.