|  | B |
SECTION B — PERFORMING OPERATIONS; TRANSPORTING

SHAPING

|  | B32 |
LAYERED PRODUCTS

|  | B32B |
LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

|  | B32B |
Note(s) The classification of layered products is provided for in many classes. However, most of these classes are confined to a particular kind of material. This sub-class provides for the classification of those inventions dealing with different kinds of material or where the characteristic feature of the invention does not reside in the particular kind of material used. Furthermore, in order that this sub-class may provide a basis for making a complete search with respect to layered products, all relevant inventions are classified here even though they may also be classified elsewhere. In this sub-class, a "layer" is a sheet or strip or anything else having a small thickness relatively to its other dimensions which, together with at least one other layer, exists in a product, whether it pre-existed, e.g. as a separate sheet or strip, or was formed during the production of the layered product. It may or may not be homogeneous or cohesive; it may be an assembly of fibres or pieces of material. It may be discontinuous, e.g. in the form of a grating, honeycomb, or frame. It may or may not be in complete contact with the next layer, e.g. a corrugated layer against a flat layer. A film formed on a layer by spreading a substance thereon is not considered to constitute a layer itself if it serves only as an adhesive or its purpose is merely to finish a surface of a product. A layered product comprises at least two layers secured together. The term "secured" is to be interpreted broadly to include any method of uniting layers, e.g. needling, stitching, gluing, nailing, dove-tailing or the interposition of an adhesive or adhesive impregnated support. The layers are preformed layers or layers formed in situ on a preformed layer and may consist of coherent solid materials, including honey-combs and other cellular materials or of non-coherent solid materials composed of assemblies of strands, strips, fibres, tiles or the like. This sub-class also includes a product similar to that described in (c) but comprising only material in the form of a sheet or network embedded in a mass of plastics or of physically-similar substances which mass penetrates the said sheet or network and lies on both sides of the latter (e.g. so that the sheet or network reinforces the plastics substance) provided that the embedded sheet or network extends coherently or connectedly over substantially the whole area of the product; thus the embedded sheet or network may be a fabric or a series of rods connected by cross wires. The manner of making such a product is, however, classified here only if it is essentially a process of building-up an assembly of layers of which at least one outer layer is preformed. If the embedded material comprises only a series of unconnected rods, the product is not classified here. A layered product may be an intermediate stage in the production of an article which is not layered in its final form, e.g. a panel with a protective layer which is stripped off when the panel is placed in its position of use. This sub-class does not include the following: Processes and apparatus used in, or in connection with, the production or treatment of any product, if the process or apparatus is fully classifiable in a single other class or sub-class for processes or apparatus, e.g. Fulltext... Hierarchy... Expanded...B05, Fulltext... Hierarchy... Expanded...B29, Fulltext... Hierarchy... Expanded...B44D, Fulltext... Hierarchy... Expanded...C08J, Fulltext... Hierarchy... Expanded...C09J, Fulltext... Hierarchy... Expanded...C23. Compositions and preparation or treatment thereof, unless the invention is essentially restricted to layered products and cannot be fully classified in another class without ignoring this restriction. Etched metallic pattern on the surface of a printed circuit board. [3] The following observations are of importance in considering the elaborations of this sub-class: In so far as methods and apparatus are classified in this sub-class, groups designating products cover also methods and apparatus specially adapted for producing such products. The term "filamentary layer" means a layer of threads or filaments of any substance (e.g. wires) of more or less unlimited length placed in an orderly arrangement and secured together; it may be woven, knitted, braided, or netted, or formed of threads crossed or laid side by side and bonded together. The term "fibrous layer" means a random assembly of fibres or filaments, usually of limited length, e.g. felt, fleece; the fibres may or may not be interengaged or connected, e.g. by adhesive. At each level of indentation, subject matter covered by two or more of the groups of this sub-class is classified in the first appropriate place, except where the contrary is indicated by precedence notes.