There are provided a very thin martensitic stainless steel foil and a manufacturing method thereof, which are capable of reducing shape defects and the like. A martensitic stainless steel foil of the present invention has a thickness of at most 35 ?m, and having a steepness of at most 0.75% when the steel foil has a length of 650 mm. Preferably, a metallographic structure in a cross-section of the steel foil is a ferrite structure, in which carbides are dispersed. More preferably, the steel foil consisting of, by mass, 0.25% to 1.5% C, 10% to 18% Cr, at most 1.0% Si (exclusive of 0%), at most 1.5% Mn (exclusive of 0%), at most 3.0% Mo (inclusive of 0%), and the balance of Fe with inevitable impurities.

Polymers used as rolling lubricating agents, to compositions including said polymers, and to alkali metal films including the polymers or compositions on the surface(s) thereof. The use of said polymers and compositions is also described for strip-rolling alkali metals or alloys thereof in order to obtain thin films. Methods for producing said thin films, which are suitable for use in electrochemical cells, are also described. An improved lubricant according to formula I, which, for example, achieves enhanced conductivity, and/or enables the production of electrochemical cells having an improved life span in cycles.

Polymers used as rolling lubricating agents, to compositions including said polymers, and to alkali metal films including the polymers or compositions on the surface(s) thereof. The use of said polymers and compositions is also described for strip-rolling alkali metals or alloys thereof in order to obtain thin films. Methods for producing said thin films, which are suitable for use in electrochemical cells, are also described. An improved lubricant according to formula I, which, for example, achieves enhanced conductivity, and/or enables the production of electrochemical cells having an improved life span in cycles.

A copper foil for producing graphene, having 60 degree gloss of 500% .Iadd.or more .Iaddend.in a rolling direction and a direction transverse to .Iadd.the .Iaddend.rolling direction, and an average crystal grain size of 200 m or more after heating at 1000 C. for 1 hour in an atmosphere containing 20% by volume or more of hydrogen and balance argon.

A copper foil for producing graphene, having 60 degree gloss of 500% .Iadd.or more .Iaddend.in a rolling direction and a direction transverse to .Iadd.the .Iaddend.rolling direction, and an average crystal grain size of 200 m or more after heating at 1000 C. for 1 hour in an atmosphere containing 20% by volume or more of hydrogen and balance argon.

An aluminum foil includes a first main surface and a second main surface located opposite to the first main surface. In at least one of the first main surface and the second main surface, a surface roughness Ra is not more than 10 nm, a surface roughness Rz is not more than 40 nm in each of a rolling direction and a direction perpendicular to the rolling direction, and the number of peak counts is not less than 10 when a reference length is 40 m, the number of peak counts being determined from a roughness curve in at least one of the rolling direction and the direction perpendicular to the rolling direction.

An aluminum foil includes a first main surface and a second main surface located opposite to the first main surface. In at least one of the first main surface and the second main surface, a surface roughness Ra is not more than 10 nm, a surface roughness Rz is not more than 40 nm in each of a rolling direction and a direction perpendicular to the rolling direction, and the number of peak counts is not less than 10 when a reference length is 40 m, the number of peak counts being determined from a roughness curve in at least one of the rolling direction and the direction perpendicular to the rolling direction.

The present invention relates to polymers used as rolling lubricating agents, to compositions comprising said polymers, and to alkali metal films including the polymers or compositions on the surface(s) thereof. The use of said polymers and compositions is also described for strip-rolling alkali metals or alloys thereof in order to obtain thin films. Methods for producing said thin films, which are suitable for use in electrochemical cells, are also described. The present invention proposes an improved lubricant according to formula I, which, for example, achieves enhanced conductivity, and/or enables the production of electrochemical cells having an improved life span in cycles.

The present invention relates to polymers used as rolling lubricating agents, to compositions comprising said polymers, and to alkali metal films including the polymers or compositions on the surface(s) thereof. The use of said polymers and compositions is also described for strip-rolling alkali metals or alloys thereof in order to obtain thin films. Methods for producing said thin films, which are suitable for use in electrochemical cells, are also described. The present invention proposes an improved lubricant according to formula I, which, for example, achieves enhanced conductivity, and/or enables the production of electrochemical cells having an improved life span in cycles.

A rolled foil formed of the FeCu alloy according to an embodiment of the present invention is manufactured to consist of 3 to 30 wt % iron and 70 to 97 wt % copper having a thickness of 100 m to 10 m, by casting a molten metal of a FeCu parent alloy and a metal copper into a slab, heat-treating the slab, and roll-milling the heat-treated slab by using a multi-pass rolling mill with the total reduction ratio of 90% or higher. In this regard, the FeCu alloy rolled foil according to the present invention provides an effect of shielding electromagnetic waves of 80 dB or more within high frequencies ranging between 1 GHz to 1.5 GHz.