JPS5812715A - Mold for resin molding - Google Patents

Abstract

PURPOSE:To enable saving of energy, by mounting a heat insulating sheet at one side or both sides of a template in a mold for resin molding. CONSTITUTION:A heat insulating sheet 4, sandwitched between steel sheets 5 and 6, is located betweeen a movable template 7 in a mold for resin molding, such as injection molding, compression molding, transfer molding and the like, and a spacer block 2, and a heat insulating sheet 12 is situated between a template 8 and a top plate 9. It is advisable that ceramics with a thermal conductivity of 0.04cal/sec.deg.cm or less, a complex of ceramics and resin, or a low-thermal conductive metal is used as the heat insulating sheet.

Description

[Detailed description of the invention] The present invention relates to a mold for resin molding.

In well-known resin molding methods such as injection molding, compression molding, and transfer molding, temperature control of the mold is a necessary condition for obtaining good molded products.

A mold temperature controller that circulates water and oil prior to molding operations,
The electric heater is activated to heat the mold to a predetermined temperature.The size of the mold depends on the size of the product,
It is determined by the number of cavities to be molded, the resin pressure, etc., and is almost never determined by the heat capacity. For this reason, the heat capacity of the mold becomes very large, and it sometimes takes several hours to reach a predetermined temperature.

In view of this, the present invention provides a resin molding mold that incorporates a heat insulating plate into the molding mold from the viewpoint of energy saving, so that only the molding plate that requires mold temperature control needs to be heated. This is what we intend to provide. This makes it possible to shorten the standing time and time required to start molding. Also, less energy is required for temperature control during molding. After the resin is fired, after the resin has cooled to the solidification point, it is heated again rapidly to melt the area near the surface of the molded product, give it a glossy surface, and remove residual stress from the injection molding process to adjust the shape. It is possible to remove distortion.

If such operations were to be performed without using a heat insulating plate, a temperature control circuit would have to be installed near the surface of the cavity to locally raise and lower the temperature of a part of the cavity, which would reduce mold strength and There remains a problem with the stability of '1k111 key.

The resin molding mold having a heat insulating plate according to the present invention is more effective for compression molding which performs humidity psyching to melt and solidify the resin in the mold than for creative molding where the mold temperature is kept constant. It is also effective in injection 1-fE &tit molding for manufacturing discs for video discs.

The present invention will be explained below with reference to the drawings showing embodiments. Fig. 1 shows an injection mold incorporating a heat insulating plate as a first embodiment. In Fig. 1, (1) The movable side collection is a board, C2) is a spacer block, (3)
is an ejector plate, (4) is a heat insulating plate made of a material with poor thermal conductivity sandwiched between steel plates (5) and (6), and the structure is a sandwich between this heat insulating plate (4) and the steel plate. is located between the movable mold plate (7) and the spacer block (2). (8) is the fixed side template, (
Reference numeral 91 indicates a plate for mounting on the fixed side, "not" indicates an eject turbine, and (11) indicates a part of the cavity. The fixed side template (
The temperature control circuit (not shown) provided in 8) dissipates the generated heat in the heat insulating plate (4), so the ejector parts and the movable l1till lj2 are attached to the plate (1), etc. Even if the weight is large, the temperature control is within minutes + rslI
It is understood that the heat capacity of the parts that require temperature control is small.

Furthermore, when it is necessary to insulate the heat capacity of the root (9) for fixation (llli mounting), as shown in Figure 2 showing the second embodiment, the fixed side template (8) and the fixed side attachment should be attached to a plate ( 9) can be solved by providing a heat insulating plate θ between the two.In this case, it is understood that it is sufficient to consider the rirL style of only the tension plate (8). If the configurations shown in Figure 2 are combined, the heat insulation effect will be further improved.

In this way, the present invention reduces the heat capacity of the cavity part (11) by 1iu-? Hot plate (4) or and (1
21 to cut off heat conduction and reduce the effective heat capacity of the mold.

By the way, as the heat insulating plate 14) the material shown in the following table is used as the material for θ-drying. If mechanical strength is required, metal is used, but if not, metal is used, such as titanide, carbide, oxide, etc. Sintered bodies, or one or more of these tables (indicating materials and thermal conductivities), are used in combination with thermal resins, especially thermosetting resins. Outside mowing material [steel plate (5) (6
) and fixed side mounting plate (9)] thermal conductivity is 1800
X10-'(cat sec, def, cm))
1/4 of the insulation materials awarded for this invention
~115 or 400X10-' (cat/(see,
It is desirable to have a thermal conductivity of less than (def, cm)).

The resin molding mold of the present invention can be implemented as described above, and a heat insulating plate is incorporated in the molding die opposite to the molding plate, and the molding die requires mold temperature control. You only need to adjust the temperature. This makes it possible to shorten the rise time until the start of molding. Also, less energy is required for temperature control during molding. After the resin has been exposed to light, after the resin has cooled to the solidification point, it is rapidly heated again to give the surface of the molded product an 861 gloss, and the residual stress at the time of injection light is removed to adjust the shape and distort it. becomes possible to remove.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of an injection mold according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of essential parts showing a second embodiment of the present invention. (1)...Movable side mounting plate, (2)...Spacer block, (3)...Ejector plate, (4
)...Insulation &, (51(6)...Copper plate, (7)...
・Side template, (6)...Fixed 1+"++!'
r'lI plate, 19)... fixed side "1v +) plate, lIO+... ejector turbine, (Ill... gear bit part, (+21... insulation plate agent Mori)
Yoshihiro Moto (7) Figure No. / (/ // Figure ?

Claims (1)

[Scope of Claims] L A resin molding mold for injection molding, compression molding, transfer molding, etc., characterized in that a heat insulating plate is placed on one or both sides of a mold plate. . 2 As a heat insulating board, the thermal conductivity value is α04'Cat/(s
ee. den, cm) or less, a composite of ceramic and resin, or a metal with low thermal conductivity.