1. Process for depositing metal coatings adhering, resistantly to aqueous-alkaline solutions, on polyimide surfaces, particularly for producing micro-fine conductor track structures, with the following essential process steps:
a) deposition of a first low-carbon and low-oxygen metal coating on the polyimide surfaces by decomposition of volatile metal compounds by means of a glow discharge process in the presence of a gas mixture containing inert gases and oxygen-containing compounds;
b) electroless deposition of a second metal coating on the first metal coating from an acidic or neutral metallising bath.
2. Process according to claim 1, characterised in that inert gases selected from the group of the rare gases and nitrogen are used.
3. Process according to one of the preceding claims, characterised in that oxygen (O2) is used as an oxygen-containing compound.
4. Process according to one of the preceding claims, characterised in that the ratio of the partial pressure of the oxygen-containing compounds to that of the inert gases in the gas mixture is set to a value between 2:1 and 1:8, preferably between 1:3 and 1:4.
5. Process according to one of the preceding claims, characterised in that the partial pressure of the gas mixture is set to a value of between 1 Pa and 50 Pa.
6. Process according to one of the preceding claims, characterised in that palladium compounds are used as volatile metal compounds.
7. Process according to one of the preceding claims, characterised in that the first metal coating is deposited at a thickness of from 0.01 m to 0.1 m.
8. Process according to one of the preceding claims, characterised in that the pH value of the metallising bath for electroless deposition is set between 2 and 8, preferably between 2 and 7.
9. Process according to one of the preceding claims, characterised in that, for electroless metallisation, a nickel, copper, cobalt, palladium or alloy bath of these metals is used.
10. Process according to one of the preceding claims, characterised in that a nickelboron alloy layer or a nickelphosphorus alloy layer with a phosphorus content of between 3 and 5% by weight of phosphorus, or a palladium layer is deposited in an electroless manner as the second metal coating.
11. Process for manufacturing an electrical circuit base, comprising an electrically non-conducting substrate with polyimide surfaces, conductor tracks with conductor track widths and spacings of substantially below 100 m and with holes with diameters of substantially under 100 m, capable of being produced by means of the following essential process steps:
application of a metal coating to at least one substrate surface,
structuring of the metal coating by means of a photo-masking technique,
etching of the holes in the substrate by means of a vacuum etching process,
removal of the metal coating,
pre-treatment of the surfaces and aperture walls by means of a glow discharge process with an oxidising gas mixture containing an oxygen-containing compound,
deposition of metal coatings according to one of the preceding claims, and
structuring of individual metal coatings by means of a photo-masking technique.
12. Process for depositing metal coatings on polyimide surfaces, characterised by all the new features and combinations of disclosed features.
13. Process for producing an electrical circuit base, characterised by all the new features and combinations of disclosed features.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A roll paper printer comprising:
a roll paper compartment adapted to rotably support a paper roll having opposite ends;
a first and a second positioning member with each disposed at a position to contact or oppose an outer circumferential part of a respective one of the two opposite ends of the paper roll;
an urging member arranged to urge the first and the second positioning member towards each other and towards the opposite ends of the paper roll; and
a plurality of roll paper guides arranged in pairs to form opposite sides of the roll paper compartment, each pair being separated by a gap, wherein the gaps between the respective roll paper guide pairs narrow approaching a printing position.
2. The roll paper printer described in claim 1, wherein:
the urging member is a tension spring connected between the first and the second positioning member.
3. The roll paper printer described in claim 1, wherein:
each of the first and the second positioning member has a roll paper guide surface for guiding the roll paper.
4. The roll paper printer described in claim 1, wherein:
the roll paper compartment is arranged to hold the roll paper at the bottom of the roll paper compartment.
5. The roll paper printer described in claim 1, wherein:
the first and the second positioning members are disposed movably widthwise to the roll paper compartment.
6. The roll paper printer described in claim 2, further comprising:
a cover for opening and closing a roll paper loading opening of the roll paper compartment;
wherein the urging member and the first and the second positioning member are disposed to the cover.
7. The roll paper printer described in claim 1, wherein:
the first and the second positioning member are located beside the roll paper guide pair that is farthest from the printing position when seen in the direction of roll paper rotation.
8. The roll paper printer described in claim 5, wherein:
the first and the second positioning member are pivotally mounted on support pins for symmetrical movement widthwise to the printer from the opposite sides of the roll paper compartment.