Injection molding method with surface modification
View Patent ↗A molded article includes thermoplastic resin, and an organic material different from the thermoplastic resin inside said molded article, the organic material being located on and near a surface of said molded article.
1. A method for manufacturing a molded article through injection molding of thermoplastic resin, said method comprising the steps of:
injecting the thermoplastic resin into a mold; and
adding a supercritical fluid containing a dissolved organometallic complex material to the mold; and
separating the dissolved organometallic complex material on and modifying a surface of the molded article.
2. The method according to claim 1 , wherein said injecting step includes the steps of:
filling the thermoplastic resin into the mold; and
introducing the supercritical fluid and organometallic complex material into the mold at a specific position of the mold.
3. The method according to claim 2 , further comprising the step of arranging the organometallic complex material in the thermoplastic resin at the specific position by adjusting pressure and/or temperature of the mold.
4. The method according to claim 2 , wherein said injecting step uses a stamper to be compressed against the thermoplastic resin that has filled up the cavity, and the stamper has a first surface that includes a predetermined pattern and is to be compressed against the thermoplastic resin, and a second surface that is opposite to the first surface and has a perforation connected to the pattern on the first surface.
5. The method according to claim 1 , further comprising:
compressing the thermoplastic resin after said injecting step; and
increasing a volume of a cavity in the mold and expanding the thermoplastic resin after said compressing step.
6. The method according to claim 1 , wherein essentially only a surface of the thermoplastic resin is modified by the supereritical fluid and organometallic complex material.
7. A method for manufacturing a molded article through injection molding of thermoplastic resin, said method comprising the steps of:
injecting the thermoplastic resin and a first supercritical fluid component containing a dissolved organometallic complex material into a mold wherein the supercritical fluid component containing the dissolved organometallic complex material is in a flow front of the thermoplastic resin in injection filling; and
separating the dissolved organometallic complex material on and modifying a surface of the molded article.
8. The method according to claim 7 , wherein said injecting step includes the step of introducing, to the mold, the supercritical fluid and the organometallic complex material as counterpressure that applies pressure in a direction opposite to a flow direction of the thermoplastic resin that has been injected.
9. The method according to claim 7 , wherein said injecting step includes the step of introducing, to the mold, the supercritical fluid and the organometallic complex material in a flow front of the thermoplastic resin in plasticization metering for plasticizing and metering a predetermined amount of thermoplastic resin for a next shot.
10. The method according to claim 7 , wherein said injecting step includes the steps of:
introducing a second supercritical fluid component without the organometallic complex material into part of the thermoplastic resin except for a flow front of the thermoplastic resin; and
forming cellular porous media inside the thermoplastic resin that has been injected into the mold using the supercritical fluid.
11. The method according to claim 7 , wherein said injecting step includes the steps of:
filling the thermoplastic resin into the mold; and
introducing the supercritical fluid and organometallic complex material into the mold at a specific position of the mold.
12. The method according to claim 11 , further comprising the step of arranging the organometallic complex material in the thermoplastic resin at the specific position by adjusting pressure and/or temperature of the mold.
13. The method according to claim 11 , wherein said injecting step uses a stamper to be compressed against the thermoplastic resin that has filled up the cavity, and the stamper has a first surface that includes a predetermined pattern and is to be compressed against the thennoplastic resin, and a second surface that is opposite to the first surface and has a perforation connected to the pattern on the first surface.
14. The method according to claim 7 , wherein essentially only a surface of the thermoplastic resin is modified by the supereritical fluid and organometallic complex material.