NOVELTY - Production of a component of a device includes solidifying polymeric material (24) to form one cleaning layer (24b) on a major surface (21) of one side or both sides of flexible web substrate (20). Each cleaning layer forms adhesive bond to, is readily removable from without damaging or leaving residue of cleaning layer material on, and captures a number of particles (22) disposed on, the major surface on which it is formed; and the removal of each cleaning layer reveals one clean surface (28).    USE - The method is for production of a component i.e. flexible component of a device i.e. electronic device selected from electroluminescent device, photovoltaic cell, semiconductor device, organic FET, thin film transistor, or integrated circuit (all claimed). The electroluminescent device is e.g. optical LED or organic LED.    ADVANTAGE - Particles can be cleaned from a major surface of a flexible web substrate at any time it is desirable or convenient to do so (e.g. just before the major surface is to be further processed) simply by removing the cleaning layer. When there is more than 1 major surface on the flexible web substrate to be cleaned, the major surfaces can be cleaned one at a time or both at the same time, i.e. when there are multiple cleaning layers to be removed, the cleaning layers can be removed one at a time or both at the same time. When there are multiple cleaning layers to be removed, the cleaning layers can be removed and wound into a roll (e.g. on a suitably sized spool) one at a time or at the same time. The removed cleaning layer can be recycled for use as a polymeric film material having utility e.g. as a shrink wrap or a protective wrap for shipping products. If the cleaning layer comprises a multilayer construction with an overcoat of an adhesive layer, the removed cleaning layer can be used as an adhesive tape. After the cleaning layer is removed, the substrate surface is free of particles whose presence is unacceptable on the substrate surface for the particular use of the substrate. The substrate surface is free of ultra-fine particles as well as larger particles, after the cleaning layer is removed. With the cleaning layer in place, the cleanliness of the underlying substrate surface can be protected and maintained while the substrate is stored or subsequently handled, such as before the cleaning layer is removed and the substrate surface further processed or before the substrate is otherwise further processed. Each clean surface satisfies the minimum cleanliness requirements of the device. The method is capable of removing greater than or equal to 99.1, preferably 99.999% of 3 mu m size and larger particles, and greater than 99, preferably 99.999% of 1.5 or 1 mu m or submicron diameters, and larger size particles.    DETAILED DESCRIPTION - Production of a component of a device comprises providing a flexible web substrate (20) that forms part(s) of a component of a device, with the flexible web substrate having opposite sides, a major surface (21) on each side, and an indefinite length; coating to wet-out on and cover a major surface on one side or both sides of the flexible web substrate with polymeric material (24), while the flexible web substrate is moving in a down-web direction; and solidifying the polymeric material to form one cleaning layer (24b) on the major surface of one side or both sides of the flexible web substrate. Each cleaning layer forms adhesive bond to, is readily removable from without damaging or leaving residue of cleaning layer material on, and captures a number of particles (22) disposed on, the major surface on which it is formed; and the removal of each cleaning layer reveals one clean surface (28). INDEPENDENT CLAIMS are included for:    (1) a method of cleaning particles from a major surface of flexible web substrate of indefinite length; and    (2) flexible web comprising a flexible web substrate having opposite sides, a first major surface on one side, a second major surface on another side, and an indefinite length; and a first cleaning layer of solidified polymeric material coated onto, and in direct contact with, the first major surface.    DESCRIPTION OF DRAWING(S) - The drawing is a side view of a stage in carrying out the method of producing flexible component of electronic device.    Flexible web substrate (20)    Surface of flexible web substrate (21)    Particles (22)    Polymeric material (24)    Cleaning layer (24b)    Clean surface (28)