Method for forming fiber-reinforced articles

Claim 1

A method of molding a plastic part having glass fiber reinforcing comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when in a closed position to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half with a portion extending beyond said cavity; (c) moving one of said mold halves toward the other of said mold halves at a rate of speed greater than a predetermined amount until it is positioned within a predetermined distance from said other mold half; (d) reducing the speed of movement of said one mold half to a speed slower than said predetermined amount; (e) injecting a flowable molding compound into the space between said upper and lower mold halves and completing said injecting step prior to said mold halves reaching said closed position; and (f) continuing said movement at said slower speed to close said upper and lower mold halves and shape said molding compound into conformity with said cavity.

Claim 2

A method of molding a plastic part having glass fiber reinforcing comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when in a closed position to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half with a portion extending beyond said cavity; (c) moving one of said mold halves toward the other of said mold halves at a rate of speed greater than a predetermined amount until it is positioned within a predetermined distance from said other mold half; (d) reducing the speed of movement of said one mold half to a speed slower than said predetermined amount; (e) injecting a flowable molding compound into the space between said upper and lower mold halves and completing said injecting step prior to said mold halves reaching said closed position; and (f) continuing said movement at said slower speed to close said upper and lower mold halves and shape said molding compound into conformity with said cavity.

Claim 4

A method of molding a plastic part having glass fiber reinforcing comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when in a closed position to define a mold cavity corresponding to the desired shape of the part, and an overflow cavity encircling said mold cavity; (b) placing a mat of glass fiber reinforcing material in said lower half with a portion extending beyond said cavity; (c) moving one of said mold halves toward the other of said mold halves at a rate of speed within a predetermined range until it reaches a distance of less than 2 inches from said other mold half; (d) reducing the speed of movement of said one mold half to a slower speed outside of said range; (e) injecting a flowable molding compound into the space between said upper and lower mold halves and completing said injecting step prior to said mold halves reaching said closed position; and (f) completing said movement to close said upper and lower mold halves.

Claim 5

A method of molding a plastic part having glass fiber reinforcing comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when in a closed position to define a mold cavity corresponding to the desired shape of the part, and an overflow cavity encircling said mold cavity; (b) placing a mat of glass fiber reinforcing material in said lower half with a portion extending beyond said cavity; (c) moving one of said mold halves toward the other of said mold halves at a rate of speed within a predetermined range until it reaches a distance of less than 2 inches from said other mold half; (d) reducing the speed of movement of said one mold half to a slower speed outside of said range; (e) injecting a flowable molding compound into the space between said upper and lower mold halves and completing said injecting step prior to said mold halves reaching said closed position; and (f) completing said movement to close said upper and lower mold halves.

Claim 7

A method of molding a plastic part having glass fiber reinforcing using a heat settable polyester resin comprising: (a) proving a mold having upper and lower halves with contoured molding surfaces which cooperate when in a closed position to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half; (c) moving one of said mold halves toward the other of said mold halves until it reaches a distance of less than 2 inches from said other mold half; (d) moving said resin to a position adjacent said mold halves while maintaining said resin in a flowable condition having a viscosity no greater than 10,000 cps; (e) injecting said resin while in flowable condition into the space between said upper and lower mold halves and completing said injecting step prior to said mold halves reaching said closed position; and (f) continuing moving of said one mold half to close said upper and lower mold halves.

Claim 8

A method of molding a plastic part having glass fiber reinforcing using a heat settable polyester resin comprising: (a) proving a mold having upper and lower halves with contoured molding surfaces which cooperate when in a closed position to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half; (c) moving one of said mold halves toward the other of said mold halves until it reaches a distance of less than 2 inches from said other mold half; (d) moving said resin to a position adjacent said mold halves while maintaining said resin in a flowable condition having a viscosity no greater than 10,000 cps; (e) injecting said resin while in flowable condition into the space between said upper and lower mold halves and completing said injecting step prior to said mold halves reaching said closed position; and (f) continuing moving of said one mold half to close said upper and lower mold halves.

Claim 12

A method of molding a plastic part having glass fiber reinforcing using a heat settable polyester resin comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when closed to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half; (c) moving one of said mold halves toward the other of said mold halves until it reaches a distance of less than 2 inches from said other mold half; (d) moving said resin to a position adjacent said mold halves while maintaining said resin in a flowable condition having a viscosity no greater than 10,000 cps; (e) injecting said resin while in flowable condition into the space between said upper and lower mold halves; and (f) continuing moving of said one mold half to close said upper and lower mold halves with the step of injecting said resin being completed prior to completion of step (f).

Claim 13

A method of molding a plastic part having glass fiber reinforcing using a heat settable polyester resin comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when closed to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half; (c) moving one of said mold halves toward the other of said mold halves until it reaches a distance of less than 2 inches from said other mold half; (d) moving said resin to a position adjacent said mold halves while maintaining said resin in a flowable condition having a viscosity no greater than 10,000 cps; (e) injecting said resin while in flowable condition into the space between said upper and lower mold halves; and (f) continuing moving of said one mold half to close said upper and lower mold halves with the step of injecting said resin being completed prior to completion of step (f).

Claim 14

A method of molding a plastic part having glass fiber reinforcing using a heat settable polyester resin comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when closed to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half; (c) moving one of said mold halves toward the other of said mold halves until it reaches a distance of less than 2 inches from said other mold half; (d) moving said resin to a position adjacent said mold halves while maintaining said resin in a flowable condition having a viscosity no greater than 10,000 cps and a temperature of 75° to 77° F.; (e) injecting said resin while in flowable condition and a temperature of at least 90° F. into the space between said upper and lower mold halves; and (f) continuing moving of said one mold half to close said upper and lower mold halves, said mold halves being maintained at a temperature of 290°-300° F. during said steps of injecting said resin and closing said upper and lower mold halves.

Claim 15

A method of molding a plastic part having glass fiber reinforcing using a heat settable polyester resin comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when closed to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half; (c) moving one of said mold halves toward the other of said mold halves until it reaches a distance of less than 2 inches from said other mold half; (d) moving said resin to a position adjacent said mold halves while maintaining said resin in a flowable condition having a viscosity no greater than 10,000 cps and a temperature of 75° to 77° F.; (e) injecting said resin while in flowable condition and a temperature of at least 90° F. into the space between said upper and lower mold halves; and (f) continuing moving of said one mold half to close said upper and lower mold halves, said mold halves being maintained at a temperature of 290°-300° F. during said steps of injecting said resin and closing said upper and lower mold halves.

Claim 17

A method of molding a plastic part having glass fiber reinforcing comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when closed to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half with a portion extending beyond said cavity; (c) moving one of said mold halves toward the other of said mold halves at a rate of speed greater than a predetermined amount until it is positioned within a predetermined distance from said other mold half; (d) reducing the speed of movement of said one mold half to a speed slower than said predetermined amount; (e) injecting into the space between said upper and lower mold halves a liquid molding compound comprising: (i) an unsaturated polyester comprising a polycondensation product of one or more polyhydric alcohols and one or more ethylenically unsaturated polycarboxylic acids; (ii) a saturated polyester polyurethane polymer; (iii) one or more olefinically unsaturated monomers which copolymerizes with the unsaturated polyesters; (iv) one or more low-profile thermoplastic polymers which cause phase separation and porosity during a curing reaction; (v) a low temperature catalyst having an initiation reaction temperature; and (vi) a high temperature catalyst having an initiation reaction temperature at least 50° F. higher than the initiation temperature of the low temperature catalyst; and (f) continuing said movement at said slower speed to close said upper and lower mold halves and shape said molding compound into conformity with said cavity.

Claim 18

A method of molding a plastic part having glass fiber reinforcing comprising: (a) providing a mold having upper and lower halves with contoured molding surfaces which cooperate when closed to define a mold cavity corresponding to the desired shape of the part; (b) placing a mat of glass fiber reinforcing material in said lower half with a portion extending beyond said cavity; (c) moving one of said mold halves toward the other of said mold halves at a rate of speed greater than a predetermined amount until it is positioned within a predetermined distance from said other mold half; (d) reducing the speed of movement of said one mold half to a speed slower than said predetermined amount; (e) injecting into the space between said upper and lower mold halves a liquid molding compound comprising: (i) an unsaturated polyester comprising a polycondensation product of one or more polyhydric alcohols and one or more ethylenically unsaturated polycarboxylic acids; (ii) a saturated polyester polyurethane polymer; (iii) one or more olefinically unsaturated monomers which copolymerizes with the unsaturated polyesters; (iv) one or more low-profile thermoplastic polymers which cause phase separation and porosity during a curing reaction; (v) a low temperature catalyst having an initiation reaction temperature; and (vi) a high temperature catalyst having an initiation reaction temperature at least 50° F. higher than the initiation temperature of the low temperature catalyst; and (f) continuing said movement at said slower speed to close said upper and lower mold halves and shape said molding compound into conformity with said cavity.