JP2963653B2 - Apparatus and method for producing cast polyamide resin molded article - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for producing a cast polyamide resin molded article, and more particularly to an apparatus and a method for producing a plate-shaped cast polyamide resin molded article. The present invention relates to an apparatus and a method for manufacturing a cast polyamide resin molded article which can be easily adjusted and temperature controlled and can easily take out a plate-shaped molded article from a mold.

[0002]

2. Description of the Related Art In a method for producing a cast polyamide molded article,
Mold made of aluminum, iron, etc. in a hot blast stove at 180-190 ° C
After the mold was heated to the temperature set in the above, the mold at the predetermined temperature was taken out of the furnace, a polymerizable lactam liquid was poured into the mold, and the mold was placed again in a hot-blast furnace to polymerize the lactam.
However, according to this method, when the preheated mold is taken out of the hot blast stove and the lactam polymerization liquid is cast, the mold comes into contact with the outside air, causing heat unevenness at the mold temperature, thereby producing a high quality molded body. Was difficult.

Further, after the polymerization, when the mold is taken out of the hot air oven and the molded body is released, the mold temperature drops by about 40 to 50 ° C. because the mold comes into contact with the outside air. Before this, the mold had to be sufficiently heated again in a hot blast stove until the desired casting temperature was reached, and a large amount of mold preheating time was required for each mold release. For this reason, a high-speed production method in which a polymerizable lactam liquid is poured into a mold forcibly maintained at an arbitrary temperature, polymerized under adiabatic conditions, and the obtained molded body is peeled off from the mold surface, is a special method. It is disclosed in Japanese Patent Publication No. 2-44694.

[0004]

However, according to this method, the thickness is about 2 to 20 mm, and when a molded body having a thickness larger than that is produced, a temperature gradient is generated between the surface and the inside of the molded body. As a result, a molded product having a cavity defect may be obtained. In addition, when a molded product having a large size is taken out of the mold without separating the mold, an operation time is required. The present invention has been made to solve such problems.
It is an object of the present invention to provide an apparatus and a method for manufacturing a cast polyamide resin molded article, in which temperature control and temperature control of a mold are easy, and a plate-shaped molded article can be easily removed from the mold.

[0005]

That is, the present invention provides an apparatus for producing a cast polyamide resin molded article by anionically polymerizing a polymerizable lactam liquid in a mold. A fixed mold body equipped with a plate mold having the same, a movable mold body similarly equipped with a plate mold having a circulation path for flowing an oil passage therein, and between the fixed mold body and the movable mold body. A frame having an opening on one side that forms a space region for casting the polymerizable lactam liquid interposed therebetween, a spacer having a passage through which the heating medium oil flows, and a heating medium for heating the heating medium oil. And an apparatus for producing a cast polyamide resin molded article comprising a heat medium oil circulating apparatus for adjusting the temperature and feeding the same into a plate mold. The present invention also includes a case where the heat insulating material is provided on the back of the plate-shaped mold.

Further, the present invention provides a cast polyamide resin molded article by anionically polymerizing a polymerizable lactam solution comprising at least an anionic polymerization catalyst and an anionic polymerization initiator with substantially anhydrous ω-lactam in a mold. In the method
Move the one plate-like molds flow to thermostatted oil passage therein, to flow the oil passage therein in proximity to the other <br/> plate mold thermostated, the two plate-like After forming a space region for casting the polymerizable lactam solution with a spacer interposed between the molds, casting the polymerizable lactam solution into the space region and anion-polymerizing, and then forming one plate-shaped mold into the other plate. separated from Jo mold, in the manufacturing method of the casting polyamide resin molded product taking out the cast polyamide resin moldings.

[0007]

According to the production apparatus and the production method of the present invention, a space region (cavity) for casting a polymerizable lactam liquid is formed by a fixed mold body, a movable mold body, and a spacer that is a frame body having one open side. In addition, since the temperature of each component is adjusted by flowing the heat medium oil into the inside, it is possible to manufacture a molded article having a large thickness and no void defects. Moreover, since each molded body can be easily separated after casting the polymerizable lactam liquid, the molded body can be easily removed from the mold regardless of the dimensions. And, it is possible to accurately control the temperature control and temperature control of the mold from the time of casting the polymerizable lactam liquid to the time of demolding of the molded body,
Heat loss is also reduced.

[0008]

FIG. 1 is a front view of an apparatus for producing a cast polyamide resin molded article according to the present invention, FIG. 2 is a plan view showing a state of molding in FIG. 1, and FIG. 3 is a production view shown in FIG. 4 is a side view of FIG. 3, FIG. 5 is a front view of the spacer, and FIGS. 6 to 8 are cross-sectional views of FIG. 5. An apparatus 1 for manufacturing a cast polyamide resin molded article according to the present invention includes a fixed mold body 2 having a plate mold 4 mounted thereon, a movable mold body 3 also having a plate mold 4 mounted thereon, and the fixed mold body described above. It comprises a spacer 5 interposed between the movable mold body 2 and the movable mold body 3 to form a space region 7, and a heat medium oil circulation device 6.

In the fixed mold body 2, a heat insulating plate 11 is vertically fixed to a support plate 10 horizontally disposed on the leg 9, and a heat insulating material 1 such as rock wool is provided on the back of the heat insulating plate 11.
2 is mounted on the entire surface, and the plate-shaped mold 4 is held and mechanically fixed to the front surface of the heat insulating plate 11 by a frame 13 projecting therefrom.

As shown in FIGS. 3 and 4, the plate-shaped mold 4 is a hollow body formed of a plate made of metal such as aluminum, iron, or the like. Fifteen
Are provided at regular intervals and have an oil passage 16 that communicates with the heat medium oil. When the heat transfer oil enters from an oil port 17 provided on the lower side of the plate-shaped mold 4, it flows through a communicating oil passage 16 and heats the entire inside of the plate-shaped mold 4 from an oil outlet 18 provided on the upper side. It is discharged and goes to the heat medium oil circulation device 6 via the pipe 19, and circulates through the space.

In the movable mold body 3, similarly to the fixed mold body 2, a heat insulating plate 11 is vertically fixed to a horizontally arranged support plate 10, and a heat insulating material 12 is entirely covered on the rear surface of the heat insulating plate 11. The plate-shaped mold 4 is held by a frame 13 protruding from the front surface of the heat insulating plate 11 and is mechanically fixed. However, the mold body 3 is a support plate 1
A carriage 20 is provided at 0, and the carriage 20 can be manually or automatically moved on the rail 22 provided on the substrate 21 toward the fixed mold body 2 and can be separated therefrom. The plate-shaped mold 4 has the same structure as that mounted on the fixed mold body 2.

As shown in FIGS. 5 to 8, the spacer 5 is a U-shaped frame having one side open, and each side is provided with a through hole 25 through which a bolt is passed at regular intervals. Inside the frame, there is an oil passage 26 through which the heat medium oil passes, and the heat medium oil passes through an oil passage 26 from an oil port 27 provided on the lower side, and exits an oil outlet 28 provided on the upper side of the side. Heat 5 The spacer 5
Is mounted on a frame 13 provided on the fixed mold body 2 or the movable mold body 3 and is mechanically fixed.
However, in order to enhance the sealing effect between the spacer 5 and the plate mold 4, a sealing material made of a rubber elastic material such as urethane or silicon rubber can be attached to both surfaces of the frame of the spacer 5. In this case, it is not necessary to mechanically fix the spacer 5 to the fixed mold body 2 or the movable mold body 3.

The heat medium oil circulating device 6 includes a heating device for heating the heat medium oil placed in the tank and a pump for circulating the heat medium oil. It is connected to the plate-shaped mold 4 mounted on the mold body 3 and the spacer 5.

Next, a method for producing a cast polyamide resin molded article using the production apparatus according to the present invention will be described below. First, the spacer 5 having a predetermined thickness is fixed to the fixed mold body 2.
After being set so as to be in contact with the plate-shaped mold 4 attached to the
A space region 7 in which the polymerizable lactam liquid is poured is formed by being sandwiched between the two plate-shaped molds 4. At this time, the spacer 5 and the two plate-shaped molds 4 and 4 are mechanically fixed by bolts or a clamp device instead of the bolts.
Adjust temperature to ° C and preheat.

Thereafter, the polymerizable lactam solution is added to the space 7
And an anion polymerization is performed in a state where the metal tubular body coated with the resin material is closed in the opening of the space region. The polymerization time is 20 to 100 minutes. When this is completed, the temperature of the spacer 5 and the two plate molds 4 is reduced to 160 to 1 minute.
After the temperature is lowered to 90 ° C. and the spacer 5 and the two plate-shaped molds 4 are mechanically opened, the movable mold body 3 is moved to the original position. The obtained cast polyamide resin molded article can be easily removed from the mold.

The polymerizable lactam liquid is obtained by adding an anionic polymerization catalyst and an anionic polymerization initiator to ω-lactam, and the ω-lactam is substantially anhydrous α-piperidone, ε-caprolactam, ω-lauro. Lactam or a mixture of two or more of these, and industrially advantageous lactams are ε-caprolactam and ω-laurolactam.

As the anionic polymerization catalyst, known ω-lactam polymerization catalysts such as sodium hydride, lithium hydride, sodium and potassium can be used. 1 to 2.0 mol%. And, as the initiator for anionic polymerization, for example, N-acetyl-ε-caprolactam, isocyanate,
Diisocyanates, urea derivatives, urethanes, and isocyanurate derivatives, and the added amount thereof is preferably in the range of 0.05 to 1.0 mol% based on ω-lactam.

In the above production method, the anionic polymerization catalyst
A method of adding and mixing an anionic polymerization initiator at or after casting after adding and dissolving to a lactam, or injecting ω-lactam containing an anionic polymerization catalyst and ω-lactam containing an anionic polymerization initiator It is adjusted by a method of adding and mixing at the time of molding or after casting.

In carrying out the method of the present invention, oils, waxes, zinc stearate, calcium stearate and the like which do not inhibit polymerization, and reinforcing materials such as carbon fiber and wollastonite may be added in addition to the above components. It is possible.

[0020]

As described above, according to the present invention, the space region into which the polymerizable lactam solution is cast is formed by the fixed mold body, the movable mold body, and the spacer which is a frame having one open side. Since the heat medium oil is flowed to adjust the temperature of each component, it is possible to produce a molded article having a large thickness and no void defects, and after casting a polymerizable lactam liquid. Since each mold body can be easily separated, it is easy to remove the molded body regardless of the size.Furthermore, it is possible to adjust the temperature of the mold from the time of casting the polymerizable lactam solution to the removal of the molded body. The temperature control can be accurately controlled, and the heat loss is reduced.

[Brief description of the drawings]

FIG. 1 is a front view of an apparatus for producing a cast polyamide resin molded article according to the present invention.

FIG. 2 is a front view showing a state at the time of molding in FIG.

1. FIG. 3 is a partially cutaway front view of a plate-shaped mold used in the manufacturing apparatus shown in FIG.

FIG. 4 is a side view of FIG. 3;

FIG. 5 is a front view of a spacer.

6 is a sectional view taken along line AA of FIG.

FIG. 7 is a sectional view taken along line BB of FIG. 5;

FIG. 8 is a sectional view taken along line CC of FIG. 5;

[Explanation of symbols]

 2 Fixed mold body 3 Movable mold body 4 Plate mold 5 Spacer 6 Heat medium oil circulation device 7 Space area 15 Bar 19 Pipe

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-63-89310 (JP, A) JP-A-1-141914 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B29C 39/00-39/44 B29C 33/00-33/76

Claims (5)

(57) [Claims] 1. An apparatus for producing a cast polyamide resin molded article by anionically polymerizing a polymerizable lactam liquid in a mold, wherein a fixed mold body provided with a plate-shaped mold having an oil passage through which a heating medium oil flows. Similarly, a movable mold body equipped with a plate-shaped mold having an oil passage for flowing heat medium oil therein, and a polymerizable lactam liquid interposed between the fixed mold body and the movable mold body. An apparatus for producing a cast polyamide resin molded product, comprising: a spacer forming a space region for casting; and a heat medium oil circulating device for controlling the temperature of a heat medium oil and sending the heat medium oil to a plate-shaped mold. 2. A frame body in which the spacer is open on one side,
The apparatus for producing a cast polyamide resin molded article according to claim 1, wherein the frame has a passage for flowing the heat transfer medium oil. 3. The apparatus for producing a cast polyamide resin article according to claim 1, wherein the heat insulating material is provided on the back of the plate-shaped mold. 4. A method for producing a cast polyamide resin molded article by anionically polymerizing a polymerizable lactam liquid comprising at least an anionic polymerization catalyst and an anionic polymerization initiator on substantially anhydrous ω-lactam in a mold, One of the plate molds whose temperature has been adjusted by flowing an oil passage inside
The oil path is made to flow through the oil passage and is brought close to the other plate-shaped mold whose temperature has been adjusted, and a space region for casting a polymerizable lactam liquid with a spacer interposed between the two plate-shaped molds is formed,
After casting the polymerizable lactam liquid into the space region and conducting anionic polymerization, separating one plate mold from the other plate mold and taking out the cast polyamide resin molded body, A method for producing a molded article. 5. The method for producing a cast polyamide resin molded article according to claim 4, wherein a spacer in which a heating medium oil is flown to enable temperature control is used as the spacer .