Plastic mold structure and method of making
First Claim
1. A mold structure for forming an article from a heated, softened plastic material, said structure comprising:
- a mold core having a thermal conductivity in the range of about 1×
10-2 to 1×
10-1 cal/cm. sec. °
C. and having a mold cavity, said mold cavity having at least one surface which comprises a recessed portion and a non-recessed portion; and
an insulating mold layer having a thermal conductivity in the range of about 1×
10-4 to 5×
10-3 cal/cm. sec. °
C. and formed in and filling said recessed portion so as to provide a substantially continuous surface.
1 Assignment
0 Petitions
Accused Products
Abstract
A metal mold core which is partially insulated includes a metal continuous hard skin layer over the core and over the insulation to avoid discontinuity caused delamination in the presence of flowing injected plastic. The skin layer includes abrasion resistant nickel deposited over electroytically and electrolessly deposited copper applied over an interface metal layer on the core. The insulation layer includes multiple layers of a polyimide resin one of which layers includes glass micro spheres for decreasing the thermal conductivity to increase its insulation property and for decreasing the coefficient of thermal expansion (CTE) of the insulation to more closely match the core CTE to further preclude delamination in the presence of temperature excursions.
31 Citations
19 Claims
-
1. A mold structure for forming an article from a heated, softened plastic material, said structure comprising:
-
a mold core having a thermal conductivity in the range of about 1×
10-2 to 1×
10-1 cal/cm. sec. °
C. and having a mold cavity, said mold cavity having at least one surface which comprises a recessed portion and a non-recessed portion; andan insulating mold layer having a thermal conductivity in the range of about 1×
10-4 to 5×
10-3 cal/cm. sec. °
C. and formed in and filling said recessed portion so as to provide a substantially continuous surface. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
-
15. A mold structure for molding preheated thermoplastic into an article comprising:
-
a core having a surface with the general contour of the article to be molded, said core including cooling means; an insulating layer bonded to a portion of said contoured surface of said core for slowing initial cooling of the preheated thermoplastic during molding in the region of said portion; and a continuous metal skin having the contour and surface characteristics of the finished article bonded to and over the insulating layer and to and over the remaining portion of said core surface not covered by said insulating surface. - View Dependent Claims (16, 17, 18, 19)
-
Specification