Interior part and manufacturing method

A manufacturing method for an interior part, the interior part a panel having a front surface and a back surface being opposite to the front surface;

• and
• an airbag frame being arranged on a side of the back surface and connected to the back surface, and the airbag frame providing a chamber, and the chamber being able to accommodate an airbag;
• wherein the panel is set with a weakening line, and the weakening line surrounds an area that defines an airbag cover, and the airbag cover is set to be open up under the pressure of the airbag;
• and the weakening line has a closed contour, and the weakening line comprises an initial split portion, a sideline portion and a hinge portion,
• wherein the hinge portion and the sideline portion provide an outer contour line of the weakening line, the initial split portion is located within the area limited by the outer contour line;
• or, the hinge portion, the sideline portion and the hinge portion provide the outer contour line of the weakening line;
• wherein two ends of the initial split portion are respectively connected with the sideline portion, and tear resistance of the initial split portion, the sideline portion and the hinge portion are respectively Fa, Fb, Fc, and the Fa<Fb<Fc;
• and the method comprising following steps:
• obtaining a mold corresponding to the structure of the interior part, and the mold being corresponding to injection molding for the panel, the airbag frame, and the weakening line;
• and
• the mold being injection molded to obtain an interior part by injection molding, wherein the panel, the airbag frame, and the weakening line are integrally connected.