Method for making reinforced plastic laminates for use in the production of circuit boards
AssigneeCompositech, Inc.
InventorsJonas Medney, Fred E. Klimpl
Life of this patent
Estimating the term…
Abstract
A warp-free laminate is produced by winding a first set of strands or filaments about a flat mandrel with a second set of strands being wound transverse to the first set. The two sets may be perpendicular to each other. The filaments are maintained under a controlled tension while being impregnated with a resin and during subsequent cure of the resin. In order to permit the formation of a warp-free product, the winding pattern is such that it forms a mirror image about a neutral axis or plane of symmetry. The winding pattern may be chosen to provide interstices in a predetermined pattern permitting punching out or high speed drilling of hole openings for subsequent printed circuit applications.
Claims73
In a method for making a printed circuit board of a set of filament sections embedded in and bonded to a continuous phase of settable matrix material, the steps comprising, prior to setting or curing of such settable matrix material which holds the entire set of filament sections in fixed spatial relationship, forming at least one set of filament sections as a plurality of superposed layers of filament sections with the filament sections in each layer being arranged generally in the same direction and with the direction of the filament sections in at least one layer in such set being arranged at an angle to the direction of the filament sections in other layers in such set;
- and arranging said layers in mirror image relationship relative to a plane of symmetry parallel to the layers of the set, all of the filament sections aligned generally in the same direction being under the same tension;
- said filament sections being held on a form in fixed spatial relationship.
In a method for making a printed circuit board of a set of filament sections in a settable matrix, the steps comprising forming at least one set of filament sections on a form as a plurality of superposed layers of filament sections with the filament sections in each layer being arranged generally in the same direction and with the direction of the filament sections in at least one layer in such set being arranged at an angle to the direction of the filament sections in other layers in such set, and arranging said layers in mirror image relationship relative to a plane of symmetry parallel to the layers of the set, all of the filament sections aligned generally in the same direction being under the same tension on said form, wherein the filament sections are electrically non-conductive;
- and introducing a continuous settable matrix of electrically non-conductive material which, after setting, fixes the filament sections in position, the tension in the filament sections at the setting of the matrix being the minimum necessary to maintain alignment of the filament sections, wherein the filament sections are embedded in said matrix.
In a method for making a printed circuit board of a set of filament sections in a continuous settable matrix, the steps comprising winding at least one set of filament sections as a plurality of superposed layers of filament sections with the filament sections in each layer being arranged generally in the same direction and with the direction of the filament sections in at least one layer in such set being arranged at an angle to the direction of the filament sections in other layers in such set;
- arranging said layers in mirror image relationship relative to a plane of symmetry parallel to the layers of the set, all of the filament sections aligned generally in the same direction being under the same tension;
- and maintaining substantially constant tension in the filament sections while winding said sections around a form such that all filament sections in each layer are substantially parallel and at the same tension.
In a method for making a printed circuit board of a set of filament sections in a settable matrix, the steps comprising forming by winding on a flat mandrel at least one set of filament sections as a plurality of superposed layers of filament sections with the filament sections in each layer being arranged generally in the same direction and with the direction of the filament sections in at least one layer in such set being arranged at an angle to the direction of the filament sections in other layers in such set;
- arranging said layers in mirror image relationship relative to a plane of symmetry parallel to the layers of the set, all of the filament sections aligned generally in the same direction being under the same tension;
- introducing a settable matrix capable of bonding to said filament sections;
- and curing the matrix by electromagnetic radiation wherein an outer plate constitutes one electrical pole for such radiation, the mandrel constitutes the other electrical pole therefor, and the matrix constitutes the dielectric between the poles.
A method for making a composite of a set of filament sections in a settable resin matrix, comprising forming at least one set of filament sections as a plurality of superposed layers of filament sections with the filament sections in each layer being arranged generally in the same direction and with the direction of the filament sections in at least one layer in such set being arranged at an angle to the direction of the filament sections in other layers in such set, and arranging said layers in mirror image relationship relative to a plane of symmetry parallel to the layers of the set, all of the filament sections aligned generally in the same direction being under the same tension;
- including the steps of subjecting said set of filament sections to a vacuum;
- injecting a settable resin into the set of filament sections in an amount sufficient to enclose the entire set;
- supporting said set and resin within mold surfaces capable of holding the filament sections in their respective orientations;
- wherein the tension in the filament sections at gelation temperatures is at a value such that when reduced to ambient temperature the stresses induced by resin shrinkage, filament tension and the expansion or contraction of both due to temperature reach an equilibrium so that the net stress in the composite is not greater than the critical buckling stress;
- removing the set of filament sections and resin, within such mold surfaces, from vacuum;
- and curing the resin to a hardened condition.
In a method for making a printed circuit board of a set of filament sections in a settable matrix material, the steps comprising forming at least one set of filament sections as a plurality of superposed layers of filament sections with the filament sections in each layer being arranged generally in the same direction and with the direction of the filament sections in at least one layer in such set being arranged at an angle to the direction of the filament sections in other layers in such set;
- and arranging such layers in mirror image relationship relative to a plane of symmetry parallel to the layers of the set, all of the filament sections aligned generally in the same direction being under the same tension;
- said filament sections being formed, arranged and held on a form in fixed spatial relationship prior to the introduction of a settable matrix material in a continuous phase which bonds to the filaments thereof to form said composite.
In a method for making a printed circuit board of a set of filament sections in a settable matrix, the steps comprising forming a filamentary structure of at least one set of filament sections on a form as a plurality of superposed layers of filament sections with the filament sections in each layer being in the same direction and with the direction of the filament sections in at least one layer in such set being arranged at an angle to the direction of the filament sections in other layers in such set, and arranging said layers of said filamentary structure in mirror image relationship relative to a plane of symmetry parallel to the layers of the set, all of the filament sections aligned generally in the same direction being under the same tension;
- and impregnating said filamentary structure with a settable matrix material to form said printed circuit board by the steps of:
- supporting such filamentary structure between at least two surfaces each having a flatness and finish corresponding to the flatness and finish of the desired printed circuit board;
- subjecting the supported filamentary structure to a vacuum;
- introducing a settable matrix material into the filamentary structure in an amount sufficient to fill the desired volume of the printed circuit board;
- spacing the surfaces apart a distance corresponding to the desired dimension of such printed circuit board;
- and
- curing the matrix material to the desired hardness.
In a method for making printed circuit boards of a set of filament sections in a continuous settable matrix;
- comprising
- winding at least one filament continuously around a right quadrilateral flat form to form a set of filament sections as a plurality of superposed layers of filament sections on each side of the form, with the filament sections in each layer being arranged generally in the same direction and under the same tension, with the direction of the filament sections in at least one layer in each set being arranged perpendicular to the direction of the filament sections in other layers in such set;
- each said set being wound such that said layers are in mirror image relationship relative to a central plane of symmetry parallel to the layers of the set;
- impregnating at least one of said sets with a settable, electrically non-conductive material to form a solid matrix for said sets with the tension in the filament sections at gelation temperatures being at a value such that when reduced to ambient temperature the stresses induced by matrix shrinkage, filament tension and the expansion or contraction of both due to temperature reach an equilibrium so that the net stress in the circuit board is not greater than the critical buckling stress of the printed circuit board;
- and
- separating said sets by trimming the wound filament arrangement at edges of the flat form to form the boards.
Dependencies are inferred from the claim text.