JP6193701B2 - Manufacturing method of resin container - Google Patents

Description

  The present invention relates to a method for manufacturing a resin container, and more specifically to a method for welding a plurality of cylindrical members constituting a container.

  For example, a resin container such as a tube container that contains a liquid material such as liquid or sol (such as cosmetics) as a content, and the content can be taken out, is usually a bottomed cylindrical container that stores the content. It has a neck that is continuously fitted with a cap. An outlet for taking out the contents is opened at the tip of the neck. Such a resin container is generally manufactured integrally by a known injection molding technique or blow molding technique. However, depending on the shape and application of the resin container, there is a manufacturing method in which the container body and the neck are formed as separate members, and then both members are welded to complete the resin container.

  FIG. 1 shows a tube container 1 as an example of a resin container manufactured using a welding technique. As shown in FIG. 1 (A), the tube container 1 has an appearance in which neck portions (12, 22) are formed at both ends of a cylindrical portion (hereinafter also referred to as a sleeve portion) 11 for storing contents. It has a shape. In the illustrated tube container 1, each neck (12, 22) is formed with a male screw for mounting a cap (not shown) around the periphery, and the tip serves as an opening for taking out the contents. Yes. The two neck openings have different diameters so that the amount of content that can be removed at one time can be changed. In the tube container 1, a cylindrical sleeve portion 11 has elasticity, and when the sleeve portion 11 is pressed in the radial direction from the outside, the contents are pushed out from the opening.

  In such a tube container 1, as shown in FIG. 1B, a member (hereinafter also referred to as a tube main body member) 10 in which a sleeve portion 11 and one neck portion 12 are integrated, and the other neck portion 22 are provided. The formed members (hereinafter also referred to as head members) 20 need to be individually molded. An end portion 25 on the side to be welded in the head member 20 is inserted inside the end portion 15 on the side to be welded in the tube main body member 10, and as indicated by hatching in the drawing, A region where the end inner peripheral surface 16 and the end outer peripheral surface 26 of the head member 20 overlap is defined as a welding region 30, and both are thermally welded. As the welding technique, there are known high-frequency welding and laser welding as described in Patent Document 1 below.

  Of course, the tube container manufactured using the welding technique is not limited to the example shown in FIG. For example, rather than integrally molding various containers with different necks with different molds, only the bottomed container body is molded with the same mold, and individual molds are prepared for the neck according to the shape. In many cases, the cost of the mold is low. For example, since the container body has a simple bottomed cylindrical shape, the cost for the mold can be reduced. Since the member on the neck side is a smaller part than the container body, a multi-cavity mold can be used, and productivity is improved.

JP 2007-144909 A

  As described above, in the case of a resin container such as a tube container, it may be advantageous to manufacture by joining two members molded individually using a welding technique depending on the shape and application. However, in welding using a high frequency, a metal member for absorbing the high frequency is required. For example, an annular metal member is disposed on the outer peripheral surface 26 of the end portion 25 on the head member 20 side. The annular metal member needs to be fitted with a flat bottomed cylindrical member made of metal on the outer peripheral surface 26 of the end portion 25 of the head member 20. Thus, in high frequency welding, the cost concerning a metal member and the cost for processing the metal member into a desired shape are required, and the manufacturing cost of the tube container increases.

  In laser welding, since it is necessary to irradiate a laser beam to a welding site, as described in Patent Document 1, a member disposed on the outer side in the welding region always transmits a laser beam ( Hereinafter, it must be made of a light transmissive material. In the example shown in FIG. 1, the tube main body member 10 needs to be made of a light transmissive material. However, in the case where contents or the like that are likely to be deteriorated by ultraviolet rays are stored in the sleeve portion 11, or in the case where it is essential that the tube container 1 is a colored resin when provided as a product, the sleeve portion 11. A light transmissive material cannot be used.

  Furthermore, in the conventional laser welding technique, regardless of the type of contents, there is a major problem with the premise that a member made of a material that absorbs laser light and generates heat is placed inside a member made of a light transmissive material in the welding region. There is. Specifically, in the conventional laser welding technique, welding is performed at the interface between the outer surface of a member disposed on the inner side and the inner surface of a member made of a light transmitting material disposed on the outer side in the welding region. For this reason, the welded portion becomes “visible” from the outside, and the aesthetic appearance is greatly impaired.

  Therefore, the present invention has been made in view of the problems in manufacturing a resin container such as a tube container as described above by conventional laser welding, and a resin container having an excellent aesthetic appearance while using a laser welding technique. The main purpose is to provide a method for manufacturing at a lower cost.

The present invention for achieving the above object is a method for producing a resin container for detachably storing contents,
Using a first member made of a resin material whose end is formed into a cylindrical shape, and a second member made of a resin material whose end is formed into a cylindrical shape and transmits laser light,
A connecting step of inserting the end of the second member inside the end of the first member;
The region where the inner peripheral surface of the end portion of the first member and the outer peripheral surface of the end portion of the second member are stacked by the connecting step is a welding region, and the first member is irradiated with laser light toward the welding region. And a laser welding step for welding the ends of the second member,
The first member is colored at least at a portion corresponding to the welding region,
In the laser welding step, the laser beam is incident from a portion other than the welding region of the second member, and the laser beam is irradiated to the welding region across the internal space of the second member, Welding the inner peripheral surface of the end portion of the first member and the outer peripheral surface of the end portion of the second member in the welding region;
This is a method for manufacturing a resin container.

In the method for manufacturing a resin container, in the laser welding step, the laser welding step is performed in a state where a narrow pressure ring for fixing an outer surface shape of the welding region is mounted on an outer periphery of the end portion of the first member. It is good also as a manufacturing method of the resin container which performs.

  The resin container includes neck portions at both ends of a cylindrical container main body portion that stores the contents, and either the first member or the second member is formed by integrating the container main body portion and one neck portion. It can also be set as the manufacturing method of the resin-made containers formed.

  According to the method for producing a resin container of the present invention, a resin container excellent in aesthetics can be provided at a lower cost while using a laser welding technique. Other effects will be clarified in the following description.

It is a figure which shows an example of the resin-made containers manufactured using a welding technique. It is the schematic which shows the manufacturing method which concerns on the 1st Example of this invention. It is a figure which shows the irradiation state of the laser beam in the method of the said 1st Example. It is an external view of the narrow pressure ring used in the manufacturing method which concerns on the 2nd Example of this invention. It is the schematic which shows the manufacturing method which concerns on the said 2nd Example. It is a figure which shows the example of the resin-made containers manufactured with the method of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that in the drawings used for the following description, the same or similar parts may be denoted by the same reference numerals and redundant description may be omitted. In some drawings, unnecessary symbols may be omitted in the description.

=== First Embodiment ===
As a method of manufacturing a resin container according to the first embodiment of the present invention, as shown in FIG. 1, a tube container 1 having neck portions (12, 22) at both ends of a cylindrical sleeve portion 11 is laser welded. The method of manufacturing using technology is listed. FIG. 2 is an outline of the manufacturing method in the present embodiment, and the flow of the method will be described in the order of FIGS. In FIG. 2, for the sake of convenience, the direction of the cylindrical axis 40 of the cylindrical sleeve portion 11 is the vertical direction, and the direction orthogonal to the vertical direction is the side. Further, it is assumed that the neck portion 12 is integrally formed downward with the sleeve portion 11. In FIG. 2, the side cross section including the cylindrical shaft 40 and the outer surface are shown to be symmetrical on the paper surface. FIG. 2D is an enlarged view of a part of FIG.

  First, as shown in FIG. 2A, a tube main body member 10 in which a neck portion 12 is integrally formed below a cylindrical sleeve portion 11 having an upper end 15 opened, and a cylindrical portion 21 flat on the upper and lower sides on the lower end 25 side. The head member 20 having the neck portion 22 formed thereon is individually molded by injection molding or the like.

The tube main body member 10 is made of low density polyethylene (LDPE) and is injection-molded using a colorant for resin (processed pigment, masterbatch, etc.) and colored as a whole. In this example, it is colored black. The cylindrical sleeve portion 11 of the tube body member 10 has an outer diameter _{Q 1} is at 22.36mm thick 0.3 to 0.5 mm, and has elasticity in the radial direction.

  On the other hand, the head member 20 is molded using linear low density polyethylene (LLDPE) and has light transmittance. Specifically, when a laser beam having a wavelength of 940 nm is incident on a plate-like sample made of the same resin material, the light transmission is 72.4% when the thickness of the sample is in the range of 1.0 mm to 2.0 mm. Have a rate.

The head member 20 has a shape continuous with a neck portion 22 whose diameter is reduced through a shoulder portion 27 having an R-shaped cross section upward from a flat cylindrical portion 21 below. A flat cylindrical portion 21 in the head member 20 has a cylindrical shape with two upper and lower stages, and a cylindrical portion (hereinafter referred to as a lower cylindrical portion) 28 on the lower end 25 side has an outer diameter Q ₂ of the upper end 15 of the sleeve portion 11. almost coincides with the inner diameter _{Q 3.}

Head member 20 has an outer diameter Q ₂ below the cylindrical portion 28 is reduced in diameter relative to the outer diameter Q ₄ of the cylindrical portion of the upper, than the inner diameter Q ₆ of the cylindrical portion inner diameter Q ₅ is above the lower cylindrical portion 28 As the diameter is increased, the thickness of the lower cylindrical portion 28 is smaller than the thickness of the upper cylindrical portion. The thickness of the lower cylindrical portion 28 is 1.0 mm. The upper cylindrical portion has an outer diameter Q ₄ of 22.50 mm, which is substantially coincident with the outer diameter Q ₁ of the sleeve portion 11 of the tube main body member 10 of 22.36 mm.

When the tube main body member 10 and the head member 20 described above are prepared, the lower cylindrical portion 28 of the head member 20 is inserted inside the upper end 15 of the tube main body member 10 as shown in FIG. The member 10 and the head member 20 are connected. On the outer peripheral surface 26 of the lower cylindrical portion 28 of the head member 20 and the inner peripheral surface 17 of the tube main body member 10, a region 16 in contact with the outer peripheral surface 26 of the lower cylindrical portion 28 is a welding region 30. And as shown in (C), the lower end side of the tube main body member 10 connected to the head member 20 is attached to the rotating device 50, and the tube main body member 10 is rotated together with the head member 20 about the cylindrical shaft 40. At the same time, the laser beam L is irradiated from the outside of the head member 20 toward the welding region 30. As the laser medium, known YAG, YVO ₄ , carbon dioxide gas, excimer (rare gas atom and halogen atom), and the like can be considered. The wavelength region of the laser light L may be any region such as ultraviolet light, visible light, and infrared light. In this example, a laser beam L having a wavelength of 940 nm was irradiated with an output of 20 W using a semiconductor laser oscillator (not shown).

  In the first embodiment, the tube main body member 10 made of a colored material that absorbs the laser light L is disposed outside the welding region 30 when the laser light L is irradiated. Therefore, instead of directly irradiating the welding region 30 with the laser beam L from the outside of the tube main body member 10, the laser beam is placed at an appropriate position P other than the position where the head member 20 becomes the welding region 30, that is, other than the lower cylindrical portion 28. The laser beam L is irradiated so that an optical path is formed on a straight line connecting the incident position P and the welding region 30.

  As a result, the laser beam L incident from the incident position P passes through the head member 20 made of a light-transmitting material, traverses the inside of the head member 20, and is opposite to the incident position P with respect to the cylindrical axis 40. The welding region 30 is reached, and the tube body member 10 and the head member 20 are welded. Specifically, as shown in (D) in which the inside of the circle 60 in (C) is enlarged, the laser beam L incident on the inside of the head member 20 is a lower cylindrical portion of the head member 20 made of a light transmissive material. 28, and is irradiated to the inner peripheral surface 16 of the tube main body member 10 in the welding region 30. The inner peripheral surface 16 of the tube main body member 10 is melted by the irradiated laser beam L, and the inner peripheral surface 16 and the outer peripheral surface 26 of the head member 20 in contact therewith are welded.

  As described above, according to the manufacturing method of the present embodiment, laser welding is performed at the interface between the inner peripheral surface 17 of the colored sleeve member and the outer peripheral surface 26 of the head member 20 formed of the light transmitting material. Therefore, it is possible to manufacture a resin container such as a tube container that does not show the welded state from the outside and has an excellent aesthetic appearance. Since it is not necessary to separately arrange a metal member as in the case of high-frequency welding, it can be manufactured at low cost.

<About the incident position of the laser beam>
In the method for manufacturing a resin container according to the first embodiment, the laser beam L is incident from the head member 20 made of a light transmissive material, and the laser beam L is irradiated to the inside of the welding region 30. The incident position P of the laser beam L in the head member 20 may be any position as long as the laser beam L can be transmitted. However, depending on the surface shape of the head member 20 at the incident position P, the intensity of the laser beam L can be attenuated. There is sex.

  FIG. 3 is an explanatory diagram showing the optical path of the laser beam L. Here, an enlarged view of a circle 70 in FIG. 2C is shown. The head member 20 has a shape that reaches the neck portion 22 while decreasing in diameter from the flat cylindrical portion 21 below, and the cylindrical portion 21 and the neck portion 22 are continuously connected via an R-shaped shoulder portion 27. doing. When the laser beam L is incident from the shoulder 27, the laser beam L is more easily scattered than other portions such as the cylindrical portion 21 due to its R shape. Therefore, when the thickness at the shoulder 27 is too thick, the light transmittance is low, or the output of the incident laser beam L is weak, the laser beam L having sufficient intensity to be welded to the welding region 30 is generated. There is a possibility that it will not be irradiated. Of course, the neck portion 22 is also easily scattered like the shoulder portion 27 because the male screw 23 is formed on the outer peripheral surface.

  Therefore, it is desirable that the laser beam L be incident after removing a position where scattering of the shoulder portion 27 or the like is likely to occur. In the first embodiment, in the cylindrical portion 21 of the head member 20, the laser beam L is incident from the region from the upper end of the lower cylindrical portion 28 corresponding to the welding region 30 to the lower end of the shoulder portion 27, and the optical path of the laser beam L Is formed in a plane including the cylindrical shaft 40. Further, although the head member 20 is formed of a light transmissive material, the laser light L is attenuated when passing through the material. Therefore, in the first embodiment, the laser light L is transmitted through the head member 20 so that the crossing angle θ between the side surface of the cylindrical portion 21 of the head member 20 and the optical path of the laser light L is close to perpendicular. The distance is shortened.

=== Second Embodiment ===
In the first embodiment, in the welding region 30, the welded portion is not visible from the outside by welding the colored inner peripheral surface 16 of the tube body member 10 and the outer peripheral surface 26 of the light-transmissive head member 20. The tube container excellent in aesthetics could be manufactured. However, when the thickness of the tube main body member 10 in the welding region 30 is thin, when the output of the laser light L is excessive, or when the laser light L irradiating the welding region 30 using the optical system is condensed too much In such a case, there is a possibility that the laser beam L having excessive energy is irradiated to the welding region 30 and the tube main body member 10 is deformed so as to affect the appearance in the welding region 30. Therefore, as a second embodiment of the present invention, a resin container manufacturing method for reliably preventing deformation in the welding region 30 that affects the appearance will be described. It is assumed that the resin container manufactured here is the tube container 1 having the neck portions (12, 22) shown in FIG.

  In the second embodiment, in order to prevent the welding region 30 from being deformed, a ring-shaped jig (hereinafter also referred to as a narrow pressure ring) is mounted around the tube container 1 during laser welding. FIG. 4 shows an external view of an example of the narrow pressure ring 100. It consists of two concentric ring-shaped members (110, 120), and the outer ring-shaped member 110 is made of metal, and a resin-made ring-shaped member (hereinafter, referred to as metal ring) 110 is disposed inside the ring member (hereinafter, metal ring) 110. , Resin ring) 120 is adhered. The resin ring 120 uses a urethane resin having the same hardness as the resin (LDPE) constituting the tube main body member 10. Of course, any material may be used for the narrow pressure ring 100.

The inner and outer rings (110, 120) are each composed of a member divided into two with respect to the diameter 101 (hereinafter, half ring members: 111-112, 121-122). The half ring members (111, 112) of the outer metal ring 110 are connected to each other by a bolt 130 so that the ring-like appearance shape is maintained. Of course, the structure of the narrow pressure ring is not limited to the example shown here. Then, the inner diameter _{Q 10} of the resin ring 120 is the outer diameter of the sleeve portion 11 of the tube body member 10 _{(Q 1:} see FIG. 2 (A)) and substantially equal. Or slightly smaller.

  FIG. 5 shows an outline of the manufacturing method according to the second embodiment. FIG. 5A is a perspective view showing a state in which the narrow pressure ring 100 is attached to the tube container 1 before welding, and FIG. 5B is a view showing an irradiation state of the laser light L. FIG. FIG. 5B shows a cross-sectional view and a side view on the left and right with respect to the vertical direction as in FIG. In the manufacturing method according to the second embodiment, the sleeve portion 11 of the tube body member 10 is inserted coaxially inside the resin ring 120 of the double ring-shaped narrow pressure ring 100 during laser welding. At this time, the optical path from the incident position P of the laser beam L to the welding region 30 in the head member 20 is prevented from being blocked by the narrow pressure ring 100.

  When the tube body member 10 is inserted into the inside of the resin ring 120 of the narrow pressure ring 100, the bolt 130 is fastened. Accordingly, the narrow pressure ring 100 is mounted in a state where the inner peripheral surface of the resin ring 120 is in contact with the outer peripheral surface of the sleeve portion 11. Next, the laser beam L is irradiated to the welding region 30 while rotating the sleeve portion 10 and the head member 20 that are connected to each other with the narrow pressure ring 100 mounted around the cylindrical shaft 40, The tube member 1 is completed by welding the head member 20. According to this second embodiment, the narrow pressure ring 100 maintains the outer shape of the welding region 30 even if the welding conditions are inadequate and the welding region 30 tends to deform outward. Since it is mounted, the deformation is limited only to the inside of the tube container 1. Thereby, it can prevent reliably that the beauty | look of the tube container 1 is impaired. Since it is not necessary to set the irradiation condition of the laser beam L strictly, it contributes to cost reduction. In particular, when the thickness of the welded region 30 of the sleeve portion 11 is thin, it can be said that the manufacturing method according to the second embodiment is effective.

  The configuration and structure of the narrow pressure ring 100 are not limited to those described above. For example, the half ring members (111-112, 121-122) are not formed in a ring shape by the bolts 130, and the half ring members (111-112, 121-122) are appropriately formed such as a slide mechanism and a hinge. It may be configured to be openable and closable depending on the structure. When the half ring members (111-112, 121-122) are opened and closed, power means such as a cylinder may be used.

  The narrow pressure ring 100 may be overtightened with a strong pressure to cause deformation or scratches in the portion of the sleeve portion 11 where the narrow pressure ring 100 is attached, or the pressure is too weak to reduce the adhesion, so that the welding region 30 is reduced. When there is a possibility that the external shape of the lens cannot be maintained well, a pressure sensor and a pressure adjusting means may be provided in order to keep the narrowing pressure constant. The pressure adjusting means may be configured to selectively adjust the position and pressure. For example, during laser welding, when the outer peripheral surface of the sleeve portion 11 rises out of the original shape, feedback control may be performed so as to selectively apply pressure to the raised portion.

=== Other Embodiments ===
In the first and second embodiments, the colored tube main body member 10 and the head member 20 made of a light-transmitting material are laser welded. Of course, the head member 20 is colored and the tube main body is colored. The member 10 may be formed of a light transmissive material. In this case, in the welding region 30, the head member 20 is disposed outside, and the laser light L is incident from the tube body member 10 side.

  In the first and second embodiments, both the tube body member 10 and the head member 20 can be formed of a light transmissive material. In this case, if at least one of the inner peripheral surface 16 of the tube main body member 10 or the outer peripheral surface 26 of the head member 20 in the welding region 30 is colored, the laser light L is absorbed in the welding region 30 and the tube main body member 10. And the head member 20 can be welded. Instead of coloring the surface (16, 26) of any member (10, 20), a light-shielding film or the like may be adhered to a desired site by well-known in-mold molding or the like.

  In the above embodiment, the manufacturing method for the tube container 1 provided with the neck portions (12, 22) at both ends of the cylindrical sleeve portion 11 has been exemplified. However, the manufacturing method is the same as the embodiment of the present invention. The container to be used is not limited to this. FIG. 6 shows an example of a resin container that can be manufactured by the method of the present invention. The resin container 1b shown in FIG. 6 (A) is formed in a cylindrical shape at both ends of the sleeve portion 11 that is elastic in the radial direction, like the tube container 1 manufactured in the first and second embodiments. It is the tube container 1b provided with the neck part (12b, 22b). However, the shapes of the neck portions (12b, 22b) are different, and applicators (13b, 23b) for pressing the contents against the surface (such as skin) and applying the contents are formed on the neck portions (12b, 22b). . One neck portion 12b is a tube main body member 10b formed integrally with the sleeve portion 11, and the other neck portion 22b is a head member 20b which is laser-welded to the tube main body member 10b.

  A resin container 1c shown in FIG. 6B is a tube container 1c having a neck portion 12 only at one end of a cylindrical sleeve portion 11, and the tube main body member 10 is a head member (20, 20b). ) And is welded to the bottom member 20c. 6C is a cross-sectional view enlarging the inside of the circle 80 in FIG. 6B, and the bottom member 20c is a flat bottomed two-stage cylindrical shape with one end opened, and is inserted inside the tube body member 10. FIG. The cylindrical portion 28c is reduced in diameter. In the state in which the bottom member 20 c is inserted into the tube main body member 10, the outer peripheral surface 26 c of the reduced diameter cylindrical portion 28 c and the region facing the outer peripheral surface 26 c in the tube main body member 10 become the welding region 30. At the time of laser welding, the outer peripheral surface of the cylindrical portion 21c on the bottom surface side of the bottom member 20c is set as the incident position P, and the laser beam L is irradiated toward the welding region 30.

  In each of the above embodiments, the tube container (1, 1b, 1c) was manufactured by laser welding the two members (10-20, 10b-20b, 10-10c), but the number of members is three. It may be the above. For example, it is also conceivable that other members such as a head member are laser-welded to both ends of a hollow cylindrical member having both ends opened. Of course, the resin container which is the subject of the present invention is not limited to a tube container in which the sleeve portion has elasticity in the radial direction, and may be formed by injection molding, blow molding or the like. The tube main body member 10 may be a laminate of a metal layer such as aluminum or several kinds of resins.

  In each of the above embodiments, a cylindrical container main body is provided, and in laser welding, a laser light source is fixed, and the container is rotated around the cylindrical axis of the container main body so that the laser is spread over the entire circumference of the welding region. I was shining light. Of course, the container body may not be cylindrical, and the horizontal cross-sectional shape of the welding region may not be a circle. For example, horizontal cross-sectional shapes such as an ellipse, a triangle, and a polygon are conceivable. In such a case, instead of rotating the container, the laser light source side may be circulated along the cross-sectional shape of the welding region. Also about a narrow pressure ring, the structure and structure which can maintain the cross-sectional shape in the welding area | region of a container should just be provided. In any case, at least one of the two members to be welded to each other is formed of a light-transmitting material, and laser light is incident from the outside of the member made of the light-transmitting material to irradiate the welding region from the inside of the container. What is necessary is just to weld two members by doing.

  In addition, the above description is for making an understanding of this invention easy, and does not limit this invention. Of course, the present invention can be changed and improved without departing from the gist thereof, and the present invention includes equivalents thereof.

  The present invention is suitable, for example, as a method for manufacturing a resin container such as a tube container for removably storing contents such as liquid cosmetics.

1, 1b, 1c Resin container (tube container), 10 tube body member,
11 sleeve portion, 12 neck portion, 20 head member, 22 neck portion, 30 welding region,
100 Narrow pressure ring, L laser beam, P laser beam incident position

Claims (3)

A method for producing a resin container for storing contents in a removable manner,
Using a first member made of a resin material whose end is formed into a cylindrical shape, and a second member made of a resin material whose end is formed into a cylindrical shape and transmits laser light,
A connecting step of inserting the end of the second member inside the end of the first member;
The region where the inner peripheral surface of the end portion of the first member and the outer peripheral surface of the end portion of the second member are stacked by the connecting step is a welding region, and the first member is irradiated with laser light toward the welding region. And a laser welding step for welding the ends of the second member,
The first member is colored at least at a portion corresponding to the welding region,
In the laser welding step, the laser beam is incident from a portion other than the welding region of the second member, and the laser beam is irradiated to the welding region across the internal space of the second member, Welding the inner peripheral surface of the end portion of the first member and the outer peripheral surface of the end portion of the second member in the welding region;
A method for producing a resin container, comprising: 2. The laser welding step according to claim 1 , wherein in the laser welding step, the laser welding step is performed in a state in which a narrow pressure ring for fixing an outer surface shape of the welding region is mounted on an outer periphery of the end portion of the first member. A method for producing a resin container characterized by the above. 3. The resin container according to claim 1, wherein the resin container includes neck portions at both ends of a cylindrical container main body that stores the contents, and one of the first member and the second member is the container main body. And one neck part are integrally molded, The manufacturing method of the resin-made containers characterized by the above-mentioned.

Images