Mold, method for manufacturing plate-shaped molded article, method for manufacturing test piece, and method for predicting characteristics of resin composition molded article
A mold, a method for producing a plate-shaped molded article, and a method for producing a test piece capable of easily producing a test piece in which an orientation direction of a filler is highly aligned are provided. A method for predicting a characteristic of a resin composition molded article is also provided, the method being able to measure an anisotropy characteristic value of a resin composition by using the test piece and to improve prediction accuracy by using the characteristic value in a computer analysis. Further in detail, a mold for injection molding the plate-shaped molded article by using a molten material of a thermoplastic resin includes a runner section that has a slit gate section provided along a width direction of the plate-shaped molded article and is configured to fill a cavity with the molten material, which is injected via a sprue section, via the slit gate section.
1 . A mold for injection molding a plate-shaped molded article by using a molten material of a thermoplastic resin, the mold comprising:
a runner section that has a slit gate section provided along a width direction of the plate-shaped molded article and is configured to fill a cavity with the molten material via the slit gate section, the molten material being injected via a sprue section, wherein
the runner section divides the molten material from the sprue section, merges the divided molten materials in a portion along the slit gate section, and guides the merged molten material to the slit gate section,
wherein in a merging area along the slit gate section, the divided molten materials are merged from both sides in a perpendicular direction to a flow direction in the cavity towards a center,
wherein the runner section includes a first runner leg and a second runner leg, wherein the runner section divides the molten material from the sprue section into the first runner leg and the second runner leg, and wherein the merging area includes a first end and a second end positioned opposite the first end across the width direction of the plate shape molded article, wherein the merging area extends perpendicular to downstream portions of the first runner leg and the second runner leg, wherein the downstream portion of the first runner leg merges with the merging area at the first end of the merging area and the downstream portion of the second runner leg merges with the merging area at the second end of the merging area,
wherein the slit gate section is positioned relative to the merging area so as to guide the molten material toward a center of the slit gate section.
2 . The mold according to claim 1 , wherein
the slit gate section is thinner than the runner section.
3 . A method for producing a plate-shaped molded article comprising:
a step of using the mold according to claim 1 to fill the cavity with the merged molten material via the slit gate section.
4 . The method for producing a plate-shaped molded article according to claim 3 , wherein
an orientation tensor in the flow direction at a center of a thickness of the obtained plate-shaped molded article is in a range of 0.60 to 0.95.
5 . A method for producing a test piece comprising:
a step of cutting out a test piece from a plate-shaped molded article, which is produced by the method for producing a plate-shaped molded article according to claim 3 , along at least one angle within a range of 0° to 90° with respect to the flow direction.
6 . The method for producing a test piece according to claim 5 , wherein
an orientation tensor in the flow direction at a center of a thickness of the obtained test piece is in a range of 0.60 to 0.95.
7 . A method for predicting a characteristic of a resin composition molded article comprising:
a step of measuring a characteristic of a test piece that is produced by the method for producing a test piece according to claim 5 ; and
a step of calculating a characteristic of a resin composition molded article that differs from the test piece on the basis of the measured characteristic of the test piece.
8 . A method for producing a plate-shaped molded article comprising:
a step of using the mold according to claim 2 to fill the cavity with the merged molten material via the slit gate section.
9 . The method for producing a plate-shaped molded article according to claim 8 , wherein
an orientation tensor in the flow direction at a center of a thickness of the obtained plate-shaped molded article is in a range of 0.60 to 0.95.
10 . A method for producing a test piece comprising:
a step of cutting out a test piece from a plate-shaped molded article, which is produced by the method for producing a plate-shaped molded article according to claim 8 , along at least one angle within a range of 0° to 90° with respect to the flow direction.
11 . The method for producing a test piece according to claim 10 , wherein
an orientation tensor in the flow direction at a center of a thickness of the obtained test piece is in a range of 0.60 to 0.95.
12 . A method for predicting a characteristic of a resin composition molded article comprising:
a step of measuring a characteristic of a test piece that is produced by the method for producing a test piece according to claim 10 ; and
a step of calculating a characteristic of a resin composition molded article that differs from the test piece on the basis of the measured characteristic of the test piece.
13 . A method for predicting a characteristic of a resin composition molded article comprising:
a step of measuring a characteristic of a test piece that is produced by the method for producing a test piece according to claim 11 ; and
a step of calculating a characteristic of a resin composition molded article that differs from the test piece on the basis of the measured characteristic of the test piece.