← Back to Patent Explorer
US4916805A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for the attachment of components to a circuit board using photoactuatable adhesive

Assignee: Thera Patent GmbH and Co KG Gesellschaft fuer Industrielle Schutzrechte
•
Filing: 1989-03-01
•
Granted: 1990-04-17
•
Expires: 2009-03-01
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract For the attachment of components using the SMT method a procedure is suggested in which the adhesive used is activated prior to fitting of the components to the circuit board by irradiation with light having a wavelength in the range of 200 to 600 nm to such an extent that the desired initial tackiness is maintained and there is no formation of skin on the surface of the adhesive. This makes it possible to cause the adhesive composition to fully cure in a shorter time and at lower temperature than has been possible so far without the wettability of the adhesive during the fitting of the components to the circuit board being impaired.

Inventors

  • 👤 Klaus Ellrich
  • 👤 Oswald Gasser
  • 👤 Rainer Guggenberger
  • 👤 Erich Wanek

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 00:59
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/30; H05K3/303; H05K3/305; H05K2201/00; H05K2201/10; H05K2201/10613; H05K2201/10621; H05K2201/10636; H05K2203/00; H05K2203/05; H05K2203/0502; H05K2203/0508; H10; H10W; H10W72/00; H10W72/071; H10W72/073; H10W72/07331; H10W72/07337; H10W72/30; H10W72/351; H10W72/353; H10W72/354; Y; Y02; Y02P; Y02P70/00; Y02P70/50; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/4913; Y10T29/49144; Y10T29/49146

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 115 words
A method for the attachment of components to a circuit board comprising applying a photoactivatable adhesive to selected areas of the components or of the circuit board, activating said adhesive prior to or after application thereof by irradiation with light having a wavelength in a range of 200 to 600 nm to such an extent that a desired initial tackiness is maintained and no skin formation on the surface of the adhesive takes place, subsequently fitting the components to the circuit board thereby establishing contact between said components, adhesive and circuit board, curing said adhesive at a temperature between 60° and 140° C. and subsequently producing soldered joints between the components and the circuit board.
Claim 2
Independent Claim 115 words
A method for the attachment of components to a circuit board comprising applying a photoactivatable adhesive to selected areas of the components or of the circuit board, activating said adhesive prior to or after application thereof by irradiation with light having a wavelength in a range of 200 to 600 nm to such an extent that a desired initial tackiness is maintained and no skin formation on the surface of the adhesive takes place, subsequently fitting the components to the circuit board thereby establishing contact between said components, adhesive and circuit board, curing said adhesive at a temperature between 60° and 140° C. and subsequently producing soldered joints between the components and the circuit board.
Claim 3
Dependent Claim 34 words
The method as claimed in claim 1 wherein the activation of the adhesive is performed by irradiation with light having a wavelength of 300 to 500 for a time for 0.5 to 300 sec.
Claim 4
Dependent Claim 27 words
The method as claimed in claim 2, wherein the activation of the adhesive is performed by irradiation with light having a wavelength of 400 to 500 nm.
Claim 5
Independent Claim 37 words
The method of any one of claims 1 to 3, wherein said curing of the adhesive bond after said fitting the component to the circuit board is performed during an interval amounting to up to 15 minutes.
Claim 6
Dependent Claim 33 words
The method of claim 1, wherein a cationically curable adhesive composition being able to flow prior to activation and having a viscosity of 0.5 to 1000 Pa.s is used as said photoactivatable adhesive.
Claim 7
Dependent Claim 24 words
The method as claimed in claim 5, wherein an adhesive composition is used having a viscosity prior to activation of 0.4 to 200 Pa.s.
Claim 8
Dependent Claim 70 words
The method of claim 1, wherein an adhesive composition is used consisting of: (a) 10 to 99.95% of at least one cationically curable resin and/or cationically polymerizable monomer; (b) 0.05 to 10% by weight of at least one photoinitiator, which under the influence of light forms Lewis or Bronsted acids; and (c) 0 to 89.95% by weight of at least one filler, thixotripifying agent, adhesion promoter and/or other conventional additive.
Claim 9
Dependent Claim 74 words
The method as claimed in claim 7, wherein an adhesive composition is used which consists of: (a) 70 to 98% by weight of at least one cationically curable resin and/or cationically polymerizable monomer; (b) 2 to 6% by weight of at least one photoinitiator, which under the influence of light forms Lewis or Bronsted acids; and (c) 0 to 28% by weight of at least one filler, thixotripifying agent, adhesion promoter and/or conventional additive.
Claim 10
Dependent Claim 128 words
The method of claim 1, wherein an adhesive composition is used which consists of: (a) 10 to 89.9% by weight of at least one cationically curable resin and/or cationically polymerizable monomer; (b) 0.05 to 10% by weight of at least one photoinitiator, which under the action of light forms Lewis or Bronsted acids; (c) 0 to 89,9% by weight of at least one filler, thixotropifying agent, adhesion promoter and/or other conventional additives; (d) 0 to 80% by weight of at least one resin and/or monomer polymerizing in accordance with a radicalic polymerization mechanism; (e) 0.05 to 5% by weight of at least one photoinitiator, which under the action of light produces radicals; and (f) if needed 0.05 to 5% by weight of at least one photosensitizer and/or activator.
Claim 11
Independent Claim 35 words
The method of any one of claims 7, 8 or 9, wherein the component (a) of the adhesive composition consists at least in part of the diglycidylethers of divalent phenols and/or of divalent aliphatic alcohols.
Claim 12
Dependent Claim 62 words
The method of claim 1, wherein the activation of the adhesive is performed by irradiation with light having a wavelength of 300 to 500 nm for a time of 0.5 to 300 sec. and wherein a cationically curable adhesive composition being able to flow prior to activation and having a viscosity of 0.05 to 1000 Pa.s is used as said photoactivatable adhesive.
Claim 13
Dependent Claim 69 words
The method of claim 5, wherein an adhesive composition is used consisting of: (a) 10 to 99.95% of at least one cationically curable resin and/or cationically polymerizable monomer; (b) 0.05 to 10% by weight of at least one photoinitiator, which under the influence of light forms Lewis or Bronsted acids; (c) 0 to 89.95% by weight of at least one filler, thixotropifying agent, adhesion promoter and/or other conventional additive.
Claim 14
Dependent Claim 128 words
The method of claim 5, wherein an adhesive composition is used which consists of: (a) 10 to 89.9% by weight of at least one cationically curable resin and/or cationically polymerizable monomer; (b) 0.05 to 10% by weight of at least one photoinitiator, which under the action of light forms Lewis or Bronsted acids; (c) 0 to 89.9% by weight of at least one filler, thixotripifying agent, adhesion promoter and/or other conventional additive; (d) 10 to 80% by weight of at least one resin and/or monomer polymerizing in accordance with a radicalic polymerization mechanism; (e) 0.05 to 5% by weight of at least one photoinitiator, which under the action of light produces radicals; and (f) if needed 0.05 to 5% by weight of at least one photosensitizer and/or activator.
Claim 15
Independent Claim 35 words
The method of any one of claims 12 or 13, wherein the component (a) of the adhesive composition consists of at least in part of the diglycidylethers of divalent phenols and/or of divelent alphatic alcohols.

References Cited (Backward Citations)

US4208005A Cited
US4314870A Cited
US4358331A Cited
US4312692A Cited
US4398660A Cited
US4605465A Cited
US4427478A Cited
WO1984000464A1 Cited
US4778556A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-04-16 1993-10-16 1994-04-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-04-16 1997-10-16 1998-04-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-04-16 2001-10-16 2002-04-17 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag