Process for the production of composite molded articles

A process for the production of an integral composite molded item comprising

• (i) a surface portion comprising a synthetic resin phase containing a fibrous reinforcing material,
• (ii) a core portion comprising the synthetic resin phase containing bubble-containing particles, and
• (iii) a separation layer positioned between the surface portion and the core portion, the process comprising the steps of:
• (a) providing in a substantially sealed mold a separation layer which does not substantially pass therethrough expandable particles but which is capable of passing a thermosetting resin or its precursor that is liquidized at the time of molding, the separation layer having inner and outer side surfaces, the outer side surface of the separation layer facing towards an inner surface of the mold and the inner side surface of the separation layer facing away from the inner surface of the mold;
• (b) providing the thermosetting resin or its precursor in the mold on either or both sides of the separation layer;
• (c) arranging a fibrous reinforcing material between the outer side surface of the separation layer and the inner surface of the mold, the fibrous reinforcing material being integrated with the separation layer or separate from the separation layer but associated therewith;
• (d) providing an aggregate of expandable particles on the inner side surface of the separation layer;
• (e) causing volume expansion of the aggregate of expandable particles by elevation of temperature to thereby expand the expandable particles;
• (f) causing the thermosetting resin or its precursor to flow through the separation layer to thoroughly disperse it between the separation layer and the mold, between the separation layer and the expanded particles, and among the expanded particles to thereby fill any voids therebetween, while pressing the separation layer towards the inner surface of the mold, as the result of volume expansion in the step (e) above;
• (g) curing the thermosetting resin or its precursor to complete solidification of the thermosetting resin to form an integral composite molded item having a surface portion comprising the synthetic resin phase containing the fibrous reinforcing material and a core portion comprising the synthetic resin phase containing the expanded particles, which portions are separated by the separation layer;
• and
• (h) taking out the resulting composite molded item from the mold.

A process for the production of an integral composite molded item comprising

• (i) a surface portion comprising a synthetic resin phase containing a fibrous reinforcing material,
• (ii) a core portion comprising the synthetic resin phase containing bubble-containing particles, and
• (iii) a separation layer positioned between the surface portion and the core portion, the process comprising the steps of:
• (a) providing in a substantially sealed mold a separation layer which does not substantially pass therethrough compressed lightweight particles of an elastic material but which is capable of passing a thermoplastic resin or thermosetting resin that is liquidized at the time of molding, the separation layer having inner and outer side surfaces, the outer side surface of the separation layer facing towards an inner surface of the mold and the inner side surface of the separation layer facing away from the inner surface of the mold;
• (b) providing the thermoplastic or thermosetting resin in the mold on either or both sides of the separation layer;
• (c) arranging a fibrous reinforcing material between the outer side surface of the separation layer and the inner surface of the mold, the fibrous reinforcing material being integrated with the separation layer or separate from the separation layer but associated therewith;
• (d) providing an aggregate of compressed particles of lightweight elastic material on the inner side surface of the separation layer;
• (e) causing volume expansion of the aggregate of the compressed lightweight particles by relieving compression on the compressed lightweight particles to thereby expand the lightweight particles;
• (f) causing the resin to flow through the separation layer to thoroughly disperse it between the separation layer and the mold, between the separation layer and the expanded particles, and among the expanded particles to thereby fill any voids therebetween, while pressing the separation layer towards the inner surface of the mold, as the result of volume expansion in the step (e) above;
• (g) completing solidification of the resin to form an integral composite molded item having a surface portion comprising the synthetic resin phase containing the fibrous reinforcing material and a core portion comprising the synthetic resin phase containing the expanded particles, which portions are separated by the separation layer;
• and
• (h) taking out the resulting composite molded item from the mold.

A process for the production of an integral composite molded item comprising

• (i) a surface portion comprising a synthetic resin phase containing a fibrous reinforcing material,
• (ii) a core portion comprising the synthetic resin phase containing bubble-containing particles, and
• (iii) a separation layer positioned between the surface portion and the core portion, the process comprising the steps of:
• (a) providing in a substantially sealed mold a separation layer which does not substantially pass therethrough expandable particles but which is capable of passing a thermoplastic resin that is liquidized at the time of molding, the separation layer having inner and outer side surfaces, the outer side surface of the separation layer facing towards an inner surface of the mold and the inner side surface of the separation layer facing away from the inner surface of the mold;
• (b) providing the thermoplastic resin in the mold on either or both sides of the separation layer;
• (c) arranging a fibrous reinforcing material between the outer side surface of the separation layer and the inner surface of the mold, the fibrous reinforcing material being integrated with the separation layer or separate from the separation layer but associated therewith;
• (d) providing an aggregate of expandable particles on the inner side surface of the separation layer;
• (e) causing melting of the thermoplastic resin by elevation of temperature, and causing volume expansion of the aggregate of expandable particles by elevation of temperature to thereby expand the expandable particles;
• (f) causing the molten thermoplastic resin to flow through the separation layer to thoroughly disperse it between the separation layer and the mold, between the separation layer and the expanded particles, and among the expanded particles to thereby fill any voids therebetween, while pressing the separation layer towards the inner surface of the mold, as the result of volume expansion in the step (e) above;
• (g) completing solidification of the thermoplastic resin to form an integral composite molded item having a surface portion comprising the synthetic resin phase containing the fibrous reinforcing material and a core portion comprising the synthetic resin phase containing the expanded particles, which portions are separated by the separation layer;
• and
• (h) taking out the resulting composite molded item from the mold.

A process for the production of an integral composite molded item comprising

• (i) a surface portion comprising a synthetic resin phase containing a fibrous reinforcing material,
• (ii) a core portion comprising the synthetic resin phase containing bubble-containing particles, and
• (iii) a separation layer positioned between the surface portion and the core portion, the process comprising the steps of:
• (a) providing in a substantially sealed mold a separation layer which does not substantially pass therethrough expandable particles or compressed lightweight particles of an elastic material but which is capable of passing a synthetic resin or its precursor that is liquidized at the time of molding, the separation layer having inner and outer side surfaces, the outer side surface of the separation layer facing towards an inner surface of the mold and the inner side surface of the separation layer facing away from the inner surface of the mold;
• (b) providing the synthetic resin or its precursor in the mold on either or both sides of the separation layer;
• (c) arranging a fibrous reinforcing material between the outer side surface of the separation layer and the inner surface of the mold, the fibrous reinforcing material being integrated with the separation layer or separate from the separation layer but associated therewith;
• (d) providing an aggregate of expandable particles and/or of compressed particles of lightweight elastic material together with crushed products of used resin molded items on the inner side surface of the separation layer;
• (e) causing volume expansion of the aggregate of the expandable particles by elevation of temperature to thereby expand the expandable particles or of the aggregate of compressed lightweight particles by relieving compression on the compressed lightweight particles to thereby expand the lightweight particles;
• (f) causing the synthetic resin or its precursor to flow through the separation layer to thoroughly disperse it between the separation layer and the mold, between the separation layer and the expanded particles, and among the expanded particles to thereby fill any voids therebetween, while pressing the separation layer towards the inner surface of the mold, as the result of volume expansion in the step (e) above;
• (g) completing solidification of the synthetic resin to form an integral composite molded item having a surface portion comprising the synthetic resin phase containing the fibrous reinforcing material and a core portion comprising the synthetic resin phase containing the expanded particles which portions are separated by the separation layer;
• and
• (h) taking out the resulting composite molded item from the mold.

A process for the production of an integral composite molded item comprising

• (i) a surface portion comprising a synthetic resin phase containing a fibrous reinforcing material,
• (ii) a core portion comprising the synthetic resin phase containing bubble-containing particles, and
• (iii) a separation layer positioned between the surface portion and the core portion, the process comprising the steps of:
• (a) providing in a substantially sealed mold a separation layer which does not substantially pass therethrough expandable particles but which is capable of passing a thermosetting resin or its precursor that is liquidized at the time of molding, the separation layer having inner and outer side surfaces, the outer side surface of the separation layer facing towards an inner surface of the mold and the inner side surface of the separation layer facing away from the inner surface of the mold;
• (b) providing the thermosetting resin or its precursor in the mold on either or both sides of the separation layer;
• (c) arranging a fibrous reinforcing material between the outer side surface of the separation layer and the inner surface of the mold, the fibrous reinforcing material being integrated with the separation layer or separate from the separation layer but associated therewith;
• (d) providing an aggregate of expandable particles together with crushed products of used resin molded items on the inner side surface of the separation layer;
• (e) causing volume expansion of the aggregate of expandable particles by elevation of temperature to thereby expand the expandable particles;
• (f) causing the thermosetting resin or its precursor to flow through the separation layer to thoroughly disperse it between the separation layer and the mold, between the separation layer and the expanded particles, and among the expanded particles to thereby fill any voids therebetween, while pressing the separation layer towards the inner surface of the mold, as the result of volume expansion in the step (e) above;
• (g) curing the thermosetting resin or its precursor to complete solidification of the thermosetting resin to form an integral composite molded item having a surface portion comprising the synthetic resin phase containing the fibrous reinforcing material and a core portion comprising the synthetic resin phase containing the expanded particles which portions are separated by the separation layer;
• and
• (h) taking out the resulting composite molded item from the mold.