JPH1158437A - Method for manufacture of molded item with fine hollow conduit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of manufacturing readily resin molded items having a fine hollow conduit with uniform cross-sectional configuration. SOLUTION: This method is to form a hollow conduit by fitting a molded item 2 to be a lid in a molded item 1 with a 1 mm or less width, 1 mm or less depth minute conduit provided beforehand on the surface of a plastic resin molded item, wherein a film 3 is inserted in the mold in the direction of the molded item 1 exposed in its minute conduit molded surface for covering the minute conduit and its circumferential part, and thereafter a molded item 2 is subjected to injection molding. In this way, the molded item 1 and the molded item 2 are put together.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a molded article having a fine hollow conduit used in, for example, a microchannel capillary electrophoresis apparatus.

[0002]

2. Description of the Related Art Conventionally, as a method of forming a hollow body, there is a method of directly forming a hollow portion such as a blow molding method or a lost core method. However, these methods cannot form a fine hollow body due to accuracy problems. is there. For this reason, for example, when manufacturing a molded product having a hollow conduit having a cross section of 1 mm square, two or more molded products having a groove formed on at least one side have to be joined, and adhesion, ultrasonic Joining is performed by welding or vibration welding. However, in these steps, a problem occurs in which the cross section of the hollow body changes due to the following reasons. Therefore, if the cross section is small, satisfactory accuracy cannot be maintained. First, in the case of the bonding method, there are problems that the thickness of the bonding layer affects the cross-sectional area, and that the adhesive itself flows into the groove or protrudes. For example, 10 μm
It is difficult to use a glue to make a pipe with a square cross section. Next, in the ultrasonic welding method and the vibration welding method, since the material to be joined is locally but melted, a pipe having a cross section of, for example, 10 μm square is easily deformed and is difficult to manufacture. is there.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and provides a method capable of easily manufacturing a resin molded product having a fine hollow conduit having a uniform cross-sectional shape. The purpose is to:

[0004]

That is, according to the present invention, a molded article 2 serving as a lid is joined to a molded article 1 in which fine grooves having a width of 1 mm or less and a depth of 1 mm or less are provided in advance on the surface of a plastic resin molded article. In the method of forming a hollow conduit by inserting, in a direction in which the fine groove forming surface of the molded article 1 is exposed, the film 3 is placed in a molding die and the film 3 covering the fine groove and its peripheral edge is arranged. The present invention relates to a method for producing a molded article with a fine hollow conduit, wherein the molded article 1 and the molded article 2 are integrated by injection molding the molded article 2.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings showing an embodiment. Reference numeral 1 denotes a molded product in which fine grooves 2 are previously formed on the surface. As means for forming the fine grooves 2, direct machining may be performed on the surface of the molded article 1.
For reasons such as low productivity and poor reproducibility of fine shapes, injection molding or injection molding with a mold produced by directly inverting a master provided by machining such as diamond turning or etching on the surface of the mold by electroforming. A method by injection compression molding is preferred. Reference numeral 3 denotes through holes provided at both ends of the fine groove 2. 4 is a fine groove 2 of the molded product 1
And a plastic film which finally constitutes a conduit, and is arranged so as to cover the fine groove 2 and its peripheral edge. Reference numeral 6 denotes a lid of the molded article 1, which is injection-molded and integrated with the fine groove forming surface of the molded article 1. FIG. 3 shows the cross-sectional shape of the molding die, and the drawing shows a case where the fine groove and the convex protrusion 5 which comes into contact with the peripheral edge thereof are provided on the inner surface of the molding die facing the fine groove of the molded product 1. It is a thing. Although the projection is not always necessary, the projection can press down the periphery of the fine groove of the molded article 1 during molding of the molded article 6, so that the resin can be prevented from wrapping around and the fine groove can be protected. The material of the molded products 1 and 6 is not particularly limited, but PMMA, polycarbonate, or the like is used. It is desirable that the film 4 has elasticity, and a PET film, an epoxy-based elastomer, or the like is used. The size of the film 4 is such that at least the groove 2 is completely covered, and the thickness of the film 4 is 50 to 200 μm.

[0006] The present invention is a method in which another molded product 2 is integrated by injection molding a surface of a fine groove on the molded product 1 in a mold via a film. In the case of the present method, the resin in the molten state and the resin of the molded article 1 are brought into contact with each other by the injection molding of the molded article 2 so that they are compatible with each other on the contact surface, thereby forming a structure for sandwiching the film interposed around the groove. At this time, as for the groove shape on the molded article 1, the flow of the resin and the influence of the heat and pressure of the molten resin can be avoided because of the film. Further, a projection is provided on the inner surface of the mold opposite to the surface on which the fine groove is formed of the molded product 1 so as to be in contact with the fine groove and the peripheral portion thereof, and injection molding is performed while pressing the periphery of the fine groove of the molded product 1. Accordingly, since the groove shape and the film on the first molded product are pressed by the mold for the molded product 2, it is possible to avoid the flow of the resin and the influence of the heat and pressure of the molten resin.

[0007]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples. Example 1 First, the outer shape was 50 mm × 100 mm × 1 by injection molding.
An acrylic resin molded product 1 of t is obtained. In this injection molding die, a piece shape which is inverted by Ni electroforming from a master in which a groove is formed by etching soda glass is embedded, and the width of the molded product 1 is 100 μm on the front side and 5 μm on the bottom side.
A 70 mm long groove having a cross section of 0 μm and a depth of 50 μm is formed. Next, the molded article 1 is inserted into an injection mold capable of insert molding, and a fine groove forming surface is arranged on the side where the molded article 2 is injected.
A PET film having a thickness of 0 μm is adhered. The size of the film is 10 mm × 80 mm and is set so as to sufficiently cover the groove. Next, the molded article 2 was molded with an acrylic resin to obtain a molded article of 50 mm × 100 mm × 2 t. The molded article with the fine hollow pipe obtained in this manner had a uniform cross section throughout the pipe without deformation of the pipe.

Example 2 A molded article 1 was obtained in the same manner as in Example 1. Next, molded article 1
Is inserted into an injection mold 7 as shown in FIG. 3, and an acrylic resin film 4 having a thickness of 40 μm is adhered so as to cover the fine grooves of the molded article 1. The size of this film is 10
The size is set to be sufficient to cover the fine groove 2 with a size of 80 mm × 80 mm. Next, the molding die of the molded product 5 has a width of 3 m so as to cover a range of the outer circumference of the fine groove 2 and the through hole 3 of 1 mm.
m, a convex protrusion 5 having a height of 0.98 mm is provided, and the second molded product 5 is molded while pressing the periphery of the fine groove 2. Finally, the outer shape of the molded product is 50 mm × 100 mm × 2 t. A conjugate was obtained. The molded article with the fine hollow pipe obtained in this manner also had a uniform cross section throughout the pipe without deformation of the pipe.

[0009]

According to the production method of the present invention, it is possible to easily obtain a resin molded product having a fine hollow conduit.

[Brief description of the drawings]

FIG. 1 is a perspective view of a first molded product according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a positional relationship between a first molded product and a film according to the embodiment of the present invention.

FIG. 3 is a sectional view of a main part of a molding die showing an embodiment of the present invention.

FIG. 4 is a perspective view of a molded product with a hollow conduit showing an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st molded article 2 Micro groove 3 Through hole 4 Film 5 Convex projection 6 2nd molded article

Claims (2)

[Claims] 1. A plastic resin molded product having a width of 1
Molded product 1 provided with a fine groove of 1 mm or less and a depth of 1 mm or less
In a method of forming a hollow conduit by joining a molded article 2 serving as a lid to a mold, the molded article 1 is inserted into a molding die in a direction in which a fine groove forming surface of the molded article 1 is exposed, and the fine groove and its peripheral portion are inserted. A method of manufacturing a molded article with a fine hollow conduit, wherein a molded article 1 and the molded article 2 are integrated by disposing a film 3 covering the molded article and then subjecting the molded article 2 to injection molding. 2. A method according to claim 1, further comprising: forming a projection on the inner surface of the mold opposite to the surface on which the fine groove is formed; The method for producing a molded article with a fine hollow conduit according to claim 1, wherein the first molded article and the second molded article are integrated by injection molding.