A radio wave absorber includes a base member, and a radio wave absorption film formed on the base member. The radio wave absorption film includes at least MTC-substituted ε-Fe.sub.2O.sub.3 and black titanium oxide. The MTC-substituted ε-Fe.sub.2O.sub.3 is a crystal belonging to the same space group as an ε-Fe.sub.2O.sub.3 crystal and expressed by ε-M.sub.xTi.sub.yCo.sub.yFe.sub.2−2y−xO.sub.3 where M is at least one element selected from the group consisting of Ga, In, Al, and Rh, 0<x<1, and 0<y<1.

A device attachable to a substrate for improving penetration of wireless communication signals is provided. The device is a bendable resin configured to enhance penetration of an incidental radio wave from a first region through the substrate to a second region by forming one or more communication signal beams in the second region. The bendable resin includes a base layer of a first material, and one or more patterned elements each formed by providing a meta-pattern of a second material on the base layer. The first and second materials are different and selected from the group consisting of a dielectric material and a metallic material. Each individual patterned element is configured to tilt the incidental radio wave to form the one or more communication signal beams, wherein each individual communication signal beam is beam-focused at a predetermined focal point or a predetermined focal area in the second region.

A device attachable to a substrate for improving penetration of wireless communication signals is provided. The device is a bendable resin configured to enhance penetration of an incidental radio wave from a first region through the substrate to a second region by forming one or more communication signal beams in the second region. The bendable resin includes a base layer of a first material, and one or more patterned elements each formed by providing a meta-pattern of a second material on the base layer. The first and second materials are different and selected from the group consisting of a dielectric material and a metallic material. Each individual patterned element is configured to tilt the incidental radio wave to form the one or more communication signal beams, wherein each individual communication signal beam is beam-focused at a predetermined focal point or a predetermined focal area in the second region.

The present invention aims to provide a multi-layer sheet with excellent electromagnetic wave shielding properties. The multi-layer sheet includes an alternating multilayer unit with five or more A layer and B layer alternately laminated, in which the electromagnetic return loss at the peak top in the peak of return loss spectrum with the highest return loss at the peak top is 5 dB or more in a chart of the return loss in the multi-layer sheet.

The present invention aims to provide a multi-layer sheet with excellent electromagnetic wave shielding properties. The multi-layer sheet includes an alternating multilayer unit with five or more A layer and B layer alternately laminated, in which the electromagnetic return loss at the peak top in the peak of return loss spectrum with the highest return loss at the peak top is 5 dB or more in a chart of the return loss in the multi-layer sheet.

An electrical steel strip or sheet with a thermosetting water-based hot-melt adhesive varnish layer provided on at least one of its flat sides, a method for producing such an electrical steel strip or sheet, and a laminated core made therefrom are disclosed. In order to produce a particularly storable and aging-stable thermosetting hot-melt adhesive varnish layer on the electrical steel strip or sheet in the B state, it is proposed for the stoichiometric ratio of the epoxy groups of the epoxy resin or epoxy resins relative to the hydrogen atoms of the at least two amino groups of the hardener that is latent at room temperature to lie in the range from 1.33:1 to 5:1.

An electrical steel strip or sheet with a thermosetting water-based hot-melt adhesive varnish layer provided on at least one of its flat sides, a method for producing such an electrical steel strip or sheet, and a laminated core made therefrom are disclosed. In order to produce a particularly storable and aging-stable thermosetting hot-melt adhesive varnish layer on the electrical steel strip or sheet in the B state, it is proposed for the stoichiometric ratio of the epoxy groups of the epoxy resin or epoxy resins relative to the hydrogen atoms of the at least two amino groups of the hardener that is latent at room temperature to lie in the range from 1.33:1 to 5:1.

A composite panel having a plurality of carbon plies, a perforated metallic foil comprising several apertures and being directly secured to the plurality of carbon plies, and a protective layer made from resin reinforced with fibers which is secured to the metallic foil. The perforated metallic foil is embedded in the protective layer through its apertures. A free surface of the protective layer forms a top side of the composite panel. The thickness of the protective layer between the top side of the composite panel and the perforated metallic foil is at least 15 micrometers and the perforated metallic foil has a thickness of not more than 30 micrometers. The plurality of apertures in the aggregate defines an open area of not more than 40% of the surface area and a maximum distance between two opposed points in a perimeter of an aperture is equal to or less than 3 mm.

A composite panel having a plurality of carbon plies, a perforated metallic foil comprising several apertures and being directly secured to the plurality of carbon plies, and a protective layer made from resin reinforced with fibers which is secured to the metallic foil. The perforated metallic foil is embedded in the protective layer through its apertures. A free surface of the protective layer forms a top side of the composite panel. The thickness of the protective layer between the top side of the composite panel and the perforated metallic foil is at least 15 micrometers and the perforated metallic foil has a thickness of not more than 30 micrometers. The plurality of apertures in the aggregate defines an open area of not more than 40% of the surface area and a maximum distance between two opposed points in a perimeter of an aperture is equal to or less than 3 mm.

The present invention relates to a laminated body with electric conductor including a substrate; a functional layer having at least an adhesive layer; an electric conductor; and a protective material, wherein the substrate, the functional layer having at least the adhesive layer, the electric conductor, and the protective material are sequentially laminated in a thickness direction, and wherein a thickness of the functional layer is less than or equal to 0.300 mm.