 Coatings for cutting implements |
| We claim: 1. A method of treating an edged cutting implement which comprises depositing a coating ... |
|
| Press-cushion sheet |
| We claim: 1. A press-cushion sheet comprising a multiple-ply woven fabric having three- to six-ply ... |
|
| Membrane separation of hydrocarbons |
| OF THE INVENTION As was previously discussed, the present invention relates to a process for the ... |
|
| Chromatographic separation method and associated apparatus |
| The present invention has met the above-described need by providing means for effectively ... |
|
| Photomask blank and photomask |
| It is an object of this invention to overcome the problems encountered with respect to known hard ... |
|
| Fine screen and fine screen stack, their use and process for the manufacture of fine screens |
| The problem addressed by the invention is the creation of fine screens which combine the good ... |
|
| Inorganic porous membrane |
| What is claimed is: 1. A multilayer inorganic porous membrane consisting of a monolayer or ... |
|
| Spray-applied fluoropolymer films for gas separation membranes |
| What is claimed is: 1. A Process for preparing a gas separation membrane comprising a microporous ... |
|
| Gas drying apparatus and method |
| I have found that a certain arrangement of perforated plates will enhance the efficiency of ... |
|
|
Structuring of printed circuit boards
| Details |
Inventors: Schmidt, Walter; Martinelli, Marco;
Assignee: Dyconex Patente AG (Zug, CH)
Primary Examiner: Powell; William
Assistant Examiner:
Attorney, Agent or Firm: Farley; Walter C.
In the method according to the invention for the production of multilayer foil printed circuit board from preliminary products (A), with current paths (B) structured in electrical conductive layers (1,3) and with electrically conductive metal platings (C,D) from conductive layer (1) to conductive layer (3) through an insulating layer (2), or for producing semifinished products for such foil circuit boards, in first method steps a structuring means (7,7',13) is applied in controlled, local manner to the preliminary product (A) and resist layers (8,9) are coated with the preliminary product (A), the structuring means (7,7',13) being applied either to the resist layers (8,9) and the resist layer (8,9) is locally removed, or the resist layers (8,9) are applied to the structuring means (7,7',13) and in a further method step the applied structuring means (7,7',13) are removed, so that openings (10,10') are formed in the resist layers (8,9) and extend down to the insulating layer (2) and in a further method step through or blind holes (11,11') are locally etched in the insulating layer (2) at the position of the openings (10,10') and for producing electrically conductive metal platings (C,D) electrically conductive deposition substances (12) are deposited in the through or blind holes (11,11'). |
|
DETAILED DESCRIPTION Such foil circuit boards and semifinished products with metal platings can be produced according to the invention.
In the method according to the invention for the production of multilayer foil circuit boards and for the production of semifinished products for such foil circuit boards with electrically conductive metal platings in through and blind holes only the current paths and pads are photochemically structured in conductive layers of preliminary products.
The structuring of openings for the etching of through or blind holes in or through an insulating layer takes place in a non-photochemical structuring, with an ultrafine, planned locally applied and removable structuring means or material and with resist layers applied in surface coveting manner and reacting in combination with said structuring means.
The method according to the invention is used for the production of multilayer foil circuit boards from preliminary products, which in electrically conductive layers have structure current paths, which have electrically conducting metal platings between different conductive layers through an insulating layer, or for producing semifinished products for such foil circuit boards.
In first method steps a structuring material reactable with the resist layers is applied in controlled, local manner to the preliminary product and resist layers are coated with the preliminary product.
Either the structuring material is applied to the resist layers or the resist layers are applied to the structuring material.
In further method steps the resist layers are locally removed by reacting with the structuring material and the latter is removed, so that openings have formed in the resist layers and extend down to the insulating layer.
The structuring material is e.
g.
applied in drop form in planned manner to the insulating layer in a printed screen.
Such a structuring material can position on existing layers resist layers over the insulating layer or can be directly positioned on the latter
|
|
Semiconductor manufacture 
