JP7292055B2 - Extrusion blow container and method for manufacturing extrusion blow container - Google Patents

Description

The present invention relates to an extruded blown container and a method for manufacturing an extruded blown container.

BACKGROUND ART In recent years, in order to achieve product differentiation, etc., extrusion blow containers with a wide variety of shapes and appearances and excellent designs have begun to appear on the market. In the extrusion blow container that emphasizes such design, when it is used for cosmetics, for example, there is a need to give it a metallic feel (metallic luster) to exhibit a more creative appearance. .
As a method for imparting (decorating) a metallic feeling, for example, a method using coating with a metallic pigment, or a method using vapor deposition of a metal-based vapor deposition film (see, for example, Patent Document 1 below), etc. are known. there is

JP 2016-101942 A

However, when a metallic effect is imparted by coating, vapor deposition, or the like, the processes of coating and vapor deposition are required, which is troublesome and tends to increase costs. Therefore, it has been difficult to meet the demand (needs) for cost reduction of the container.

The present invention has been made in view of such circumstances, and an object of the present invention is to manufacture an extrusion blow container and an extrusion blow container that can be provided with a sufficient metallic feeling simply by performing extrusion blow molding. to provide a method.

(1) An extrusion blow container according to the present invention is an extrusion blow container having a synthetic resin container body in which a mouth portion, a body portion, and a bottom portion are continuously arranged in this order from top to bottom, wherein the container body is formed of a first synthetic resin containing a colorant and is formed of a light-transmitting outer layer and a second synthetic resin having a lower light transmittance than the outer layer, and the container an inner layer disposed radially inward of the main body, wherein the second synthetic resin contains metal powder, and the inner layer is formed by the second synthetic resin having light transmittance, It is characterized in that the outer layer has a light-transmitting property, and at least a part of the outer surface of the outer layer is formed with a roughened surface portion having a surface roughness higher than that of the inner surface of the outer layer.

According to the extrusion blow container of the present invention, the inner layer containing the metal powder can be visually recognized from the outside of the container body through the outer layer colored with the coloring agent. Therefore, a metallic feeling can be obtained by the metallic luster effect using the light reflected by the metal powder. As a result, the colored outer layer can be visually recognized while feeling a metallic feeling, so that it is possible to provide an appearance with a metallic luster.
In particular, since the inner layer is made of the second synthetic resin having a lower light transmittance than the outer layer, it is more difficult for visible light to pass through than the outer layer. Therefore, it is difficult for visible light to pass through the inner layer, the presence of the metal powder contained in the inner layer can be emphasized, and the metallic effect can be deepened. In addition, it is possible to exhibit a texture that has a silky feel with a smooth luster like silk.

From the above, it is possible to obtain an extrusion blow container having a sufficiently metallic feeling. Furthermore, since the outer layer is formed from the first synthetic resin containing the coloring agent and the inner layer is formed from the second synthetic resin containing the metal powder, the above-described container body is formed by extrusion blow molding. Thus, a sufficient metallic feeling can be provided. Therefore, unlike the case where a metallic effect is imparted by painting, deposition, or the like, it is not troublesome, and cost reduction can be achieved. Therefore, it is possible to meet the need for cost reduction of the container, and it is possible to provide an extrusion blow container that can be suitably used for various purposes such as a container for cosmetics.
Furthermore, since the inner layer itself also has optical transparency, almost all of the metal powder contained in the inner layer can be visually recognized from the outside of the container body. If the inner layer itself does not have optical transparency, only part of the metal powder present near the outer surface of the inner layer can be seen, making it difficult to obtain an appropriate metallic effect. As described above, since almost all of the metal powder contained in the inner layer can be visually recognized, the presence of the metal powder can be emphasized, and the metallic feeling can be sufficiently deep.
Furthermore, since the roughened surface is formed on the outer surface of the outer layer, the portion where the roughened surface is formed can be a silk-like grain surface (embossed surface) having minute unevenness. Therefore, the portion of the outer surface of the outer layer where the rough surface portion is formed can be formed in a semi-glossy state. Therefore, rather than making the metallic effect stand out, it is possible to provide a moist and luxurious feeling while feeling the metallic effect. In other words, it is possible to obtain a container having a unique appearance having a metallic feel and a matte texture with a suppressed glossiness.
Therefore, it is effective when it is desired to create a container that has a matte texture that brings out a calm and luxurious feeling while giving a metallic feeling.

(2) The outer layer may be thinner than the inner layer.

In this case, since the outer layer is formed thin, the visibility of the inner layer can be improved, and a better metallic effect can be obtained.

( 3 ) The container body may include an innermost layer formed of the second synthetic resin and disposed radially inward of the container body relative to the inner layer.

In this case, since the innermost layer is formed of the same second synthetic resin as the inner layer, it is possible to prevent the metal powder contained in the inner layer from coming into contact with the contents accommodated in the container body. . Therefore, it becomes possible to deal with a wide variety of contents. Moreover, since both the inner layer and the innermost layer can be formed from the second synthetic resin, it is possible to stack the inner layer and the innermost layer in a state of being in close contact with each other without, for example, interposing an adhesive layer therebetween.

( 4 ) The coloring agent may be contained in the first synthetic resin so as to have a concentration of less than 15% by weight with respect to the first synthetic resin.

In this case, it is possible to prevent the color density of the outer layer from becoming excessively high, so that the visibility of the inner layer can be appropriately ensured, and a good metallic effect can be obtained.

( 5 ) The metal powder may have a particle size of 20 μm or more.

In this case, since the metal powder having a large particle diameter of 20 μm or more is used, the visible light incident from the outside of the container body can be easily diffusely reflected by using the metal powder. Therefore, variations in glossiness are likely to occur due to changes in the incident angle of visible light, and variations in glossiness can be increased. Therefore, the metallic feeling can be emphasized while maintaining the matte texture, and the container can have a unique appearance in which the feeling of brightness is enhanced while being matte.

( 6 ) The metal powder may have a particle size of 100 μm or less.

In this case, since the maximum particle diameter of the metal powder is set to 100 μm, the molding conditions for extrusion blow molding are easily satisfied, and the extrusion blow molding is appropriately performed in a state in which the second synthetic resin contains the metal powder. Is possible. Thus, extrusion blow molding can adequately form containers having the unique appearance described above.

( 7 ) The metal powder may have a particle size of less than 20 μm.

In this case, since the metal powder having a small particle diameter of less than 20 μm is used, the visible light incident from the outside of the container body is less likely to be diffusely reflected by the metal powder. Therefore, it is easy to suppress variations in glossiness due to changes in the incident angle of visible light, and it is possible to suppress an increase in variation in glossiness. Therefore, the metallic appearance can be made uniform over the entire inner layer, and a smoother glossy appearance can be provided. Therefore, it is possible to obtain a container having a unique appearance in which both a calm metallic feeling and a smooth glossy feeling are compatible, even though the container has a matte tone.

( 8 ) The metal powder may have a particle size of 3 μm or more.

In this case, since the minimum particle diameter of the metal powder is set to 3 μm, it is possible to use known metal powder and to carry out the extrusion blow molding while appropriately containing the metal powder in the second synthetic resin. be. Thus, extrusion blow molding can adequately form containers having the unique appearance described above.

( 9 ) A method for manufacturing an extrusion blow container according to the present invention includes an outer layer formed of a first synthetic resin containing a colorant and having light transmittance, and and a light-transmitting inner layer formed of a second synthetic resin having properties and arranged radially inwardly of the outer layer, the mouth portion, the body portion and the bottom portion being arranged in this order from top to bottom. A method for manufacturing an extrusion blow container having continuous synthetic resin container bodies, comprising: a parison forming step of forming a laminated parison by extrusion; in the cavity of the molding die, and by supplying pressurized air into the laminated parison, the laminated parison is pressed against the molding surface of the molding die, and the extrusion blow a blowing step for molding a container, wherein the laminated parison is formed in a state in which the second synthetic resin is impregnated with metal powder during the parison forming step, and the mold is used as the molding die during the mold clamping step. By using a mold in which the molding surface is roughened, a roughened surface portion having a rougher surface roughness than the inner surface of the outer layer is formed on at least a part of the outer surface of the outer layer. do.

According to the method for manufacturing an extrusion-blown container according to the present invention, a series of extrusion blow-molding processes including the parison forming process, the mold clamping process, and the blowing process are performed to produce the above-described extrusion-blown container having a sufficient metallic effect. can be manufactured.
In particular, since a molding die having a roughened molding surface is used, the rough surface can be formed on the outer surface of the outer layer of the container body simply by performing blow molding. Therefore, it is possible to manufacture an extrusion-blown container having a rough surface portion without the need for post-processing and the like, and without incurring extra costs. As a result, the effects of having the rough surface portion described above can be achieved.

According to the present invention, a container having a sufficiently metallic appearance can be obtained simply by carrying out extrusion blow molding.

BRIEF DESCRIPTION OF THE DRAWINGS It is an external view (partial cross section view) which shows embodiment of the extrusion blow container which concerns on this invention. FIG. 2 is an enlarged cross-sectional view of a portion A shown in FIG. 1; FIG. 2 is an external perspective view of the vicinity of the body of the extrusion blow container shown in FIG. 1 ;

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the manufacturing method of the extrusion blow container which concerns on this invention, and an extrusion blow container is described with reference to drawings.
As shown in FIG. 1, the extrusion blow container 1 of this embodiment is an EBM bottle made of synthetic resin, and includes a bottomed cylindrical container body 10 to be filled with contents.
The container body 10 includes a cylindrical mouth portion 11, a cylindrical shoulder portion 12 connected to the mouth portion 11, a cylindrical body portion 13 connected to the shoulder portion 12, and a cylindrical body portion 13 connected to the body portion 13. and a cylindrical bottom portion 14 with a bottom provided.

The contents include, for example, foods such as beverages and seasonings, cosmetics such as emulsions, serums, and skin creams, detergents, medicines, and the like. However, it is not limited to this case, and the content is not limited to a specific one.

The mouth portion 11, the shoulder portion 12, the body portion 13, and the bottom portion 14 are connected in this order with their central axes positioned on a common axis. Hereinafter, this common axis will be referred to as a container axis O, and along the direction of the container axis O, the mouth portion 11 side will be referred to as the upper side, and the opposite side will be referred to as the lower side. Further, in a plan view seen from the direction of the container axis O, the direction intersecting with the container axis O is called the radial direction, and the direction rotating around the container axis O is called the circumferential direction.

A male screw portion 11a to which a cap (not shown) is screwed is formed on the outer peripheral surface of the mouth portion 11 over the entire circumference in the circumferential direction.
However, the method of attaching the cap is not limited to screwing. For example, the cap may be attached to the opening 11 by undercut fitting. In this case, a fitting protrusion for undercut-fitting the cap may be formed on the outer peripheral surface of the mouth portion 11 instead of the male screw portion 11a. When the cap is attached to the opening 11 by undercut fitting, the cap may be a hinged cap, for example.

The shoulder portion 12 continues to the lower end portion of the mouth portion 11 and expands in diameter so as to extend radially outward from the lower end portion of the mouth portion 11 downward. The body portion 13 continues to the lower end portion of the shoulder portion 12 and is formed to extend straight downward from the lower end portion of the shoulder portion 12 . Thereby, the trunk portion 13 is formed in a cylindrical shape having the same diameter along the axis O of the container. The bottom portion 14 continues to the lower end portion of the body portion 13 and closes the lower end opening of the body portion 13 .

However, the shape of the container body 10 is not limited, and may be changed as appropriate according to, for example, the overall size, capacity, type of content, application, etc. of the extrusion blow container 1 .
For example, the extrusion blow container may be a rectangular bottle in which the body portion 13 is formed in a polygonal shape when viewed in cross section. Furthermore, it may be an extrusion blow container having a body portion 13 whose diameter increases from the top to the bottom. Further, a container body is provided in which the upper end portion of the body portion 13 is reduced in diameter without the shoulder portion 12 and the upper end portion of the reduced diameter body portion 13 is connected to the lower end portion of the mouth portion 11. An extrusion blow container may also be used.

The container body 10 has a laminated structure in which a plurality of layers are stacked. Specifically, as shown in FIG. 2, the container body 10 has an outer layer 20, an adhesive layer 21, an inner layer 22, and an innermost layer 23, which are laminated in this order from the outside in the radial direction.

The outer layer 20 is a synthetic resin layer that forms the outer surface of the container body 10 . The outer layer 20 is made of a first synthetic resin 30 containing a coloring agent and has optical transparency.
Specifically, the first synthetic resin 30 is a resin whose main material is polyethylene terephthalate resin (PET resin). However, the first synthetic resin 30 only needs to contain PET resin, and may contain other synthetic resins or additives.
The film thickness of the outer layer 20 is, for example, around 90 μm. However, the film thickness of the outer layer 20 is an example, and may be changed as appropriate.

Examples of the coloring agent include, but are not particularly limited to, a masterbatch that is kneaded into the first synthetic resin 30 to cause the first synthetic resin 30 to develop a color.
A masterbatch is a pellet-shaped colorant in which a high-concentration pigment is kneaded. For example, the masterbatch is mixed with natural pellets in the first synthetic resin 30, and the color intensity is arbitrarily adjusted according to the ratio of the two. is possible. This allows the first synthetic resin 30 to be appropriately adjusted to a desired color tone.
The coloring agent is contained in the first synthetic resin 30 so as to have a concentration of less than 15% by weight with respect to the first synthetic resin 30 .

The colorant is not limited to a masterbatch, and for example, a colored pellet whose color concentration has been adjusted in advance may be used, or a liquid or gel paste color may be used. . Further, the color of the outer layer 20 that is colored with the coloring agent is not limited to a specific color, and may be appropriately changed according to, for example, the application of the extrusion blow container 1 and the type of contents.

Since the outer layer 20 configured as described above is colored with a coloring agent and has light transmittance, it is possible to visually recognize the inner layer 22 side through the outer layer 20 from the outside of the container body 10. there is The light transmittance required for the outer layer 20 is not particularly limited as long as it can transmit visible light, but is preferably 30% or less in terms of haze, which indicates the degree of fogging.

The inner layer 22 is arranged radially inward of the outer layer 20 and is made of a synthetic resin layer having optical transparency like the outer layer 20 . The inner layer 22 is made of a second synthetic resin 31 having a lower light transmittance than the outer layer 20 . Specifically, the second synthetic resin 31 is a resin whose main material is primary-color polypropylene resin (PP resin). However, the second synthetic resin 31 only needs to contain PP resin, and may contain other synthetic resins or additives. Also, the inner layer 22 may be formed of the second synthetic resin 31 having a lower light transmittance than the outer layer 20, and may be low in light transmittance or opaque, for example.
The thickness of the inner layer 22 is, for example, around 690 μm, which is the thickest layer among the layers constituting the container body 10 . Therefore, in this embodiment, the outer layer 20 is formed thinner than the inner layer 22 . However, the film thickness of the inner layer 22 is an example, and may be changed as appropriate.

The second synthetic resin 31 contains a plurality of metal powders 32 .
Examples of the metal powder 32 include aluminum powder in which aluminum is formed in the form of extremely thin flakes or powder. However, the material is not limited to this case, and a metal other than aluminum may be used. The particle diameter of the metal powder 32 is, for example, 3 μm or more and 100 μm or less.
The inner layer 22 is formed by extrusion blow molding a second synthetic resin 31 to which metal powder 32 is added. As a result, the metal powder 32 is evenly distributed throughout the inner layer 22 .

The adhesive layer 21 is disposed between the outer layer 20 and the inner layer 22 and has a function of firmly bonding the outer layer 20 and the inner layer 22 together. Therefore, the adhesive layer 21 overlaps the outer layer 20 and the inner layer 22 in close contact with each other. As the material for the adhesive layer 21, a known material may be selected.
The film thickness of the adhesive layer 21 is, for example, about 60 μm. However, the film thickness of the adhesive layer 21 is an example, and may be changed as appropriate. For example, the film thickness of the adhesive layer 21 may be around 10 μm.

The innermost layer 23 is a layer that forms the inner surface of the container body 10, and is disposed radially inward of the inner layer 22, and is a synthetic resin layer that overlaps the inner layer 22 in close contact therewith. . Specifically, the innermost layer 23 is made of the same second synthetic resin 31 as the inner layer 22 . In other words, the innermost layer 23 is made of a resin whose main material is polypropylene resin (PP resin).
Therefore, the innermost layer 23 is in close contact with the inner layer 22 without interposing the adhesive layer 21 described above. However, the innermost layer 23 only needs to contain PP resin, and may contain other synthetic resins or additives.
The thickness of the innermost layer 23 is, for example, around 30 μm, which is thinner than the outer layer 20 and the inner layer 22 . However, the film thickness of the innermost layer 23 is an example, and may be changed as appropriate.

By the way, at least a part of the outer surface of the outer layer 20 is formed with a rough surface portion 33 that is rougher than the surface roughness of the inner surface of the outer layer 20 (the surface to be bonded to the adhesive layer 21).
In this embodiment, the rough surface portion 33 is formed over the entire outer surface of the outer layer 20 . However, it is not limited to this case, and for example, the rough surface portion 33 may be formed only on the outer surface of the portion of the outer layer 20 that functions as the body portion 13 .
By forming the rough surface portion 33, the outer surface of the outer layer 20 is made into a silk-like fine grain surface (so-called embossed surface) having minute unevenness. The rough surface portion 33 is formed when the extrusion blow molding is performed.

(Action of extrusion blow container)
According to the extrusion blow container 1 configured as described above, the inner layer 22 containing a plurality of metal powders 32 can be visually recognized from the outside of the container body 10 through the outer layer 20 colored with the coloring agent. Therefore, a metallic feeling can be obtained by the effect of the metallic luster caused by the light reflected by the metal powder 32 . As a result, the colored outer layer 20 can be visually recognized while feeling a metallic feeling, so that it is possible to provide an appearance with a metallic luster.

In particular, since the inner layer 22 is made of the second synthetic resin 31 having a lower light transmittance than the outer layer 20 , it is more difficult for visible light to pass through than the outer layer 20 . Therefore, it is difficult for visible light to pass through the inner layer 22, and the presence of the metal powder 32 contained in the inner layer 22 can be emphasized, and the metallic feeling can be deepened. In addition, it is possible to exhibit a texture that has a silky feel with a smooth luster like silk.
Furthermore, in this embodiment, the inner layer 22 itself is also light transmissive, so that almost all of the metal powder 32 contained in the inner layer 22 can be visually recognized from the outside of the container body 10 . If the inner layer 22 itself does not have optical transparency, only a portion of the metal powder 32 present near the outer surface of the inner layer 22 can be seen, making it difficult to obtain an appropriate metallic effect. . On the other hand, according to the present embodiment, since almost all of the metal powder 32 contained in the inner layer 22 can be visually recognized as described above, the presence of the metal powder 32 can be emphasized, and the metallic feeling is sufficiently deep. can have

As described above, the extrusion blow container 1 can have a sufficiently metallic appearance. Furthermore, according to the extrusion blow container 1 of the present embodiment, it is possible to provide a sufficient metallic feeling at the time of extrusion blow molding.
A method for manufacturing the extrusion blow container 1 using extrusion blow molding will be briefly described below.

First, by extrusion molding, a first layer which is to be the outer layer 20 mainly composed of a first synthetic resin 30 containing a coloring agent, a second layer consisting of an adhesive layer 21, and a second layer containing a metal powder 32 are formed. A step of forming a bottomed cylindrical laminated parison (parison forming step) in which the third layer that is the inner layer 22 and the fourth layer that is the innermost layer 23, the main material of which is the synthetic resin 31, are combined.

Next, a step of sandwiching the laminated parison between molding dies and arranging it in the cavity is performed (mold clamping step). At this time, the molding surface of the molding die is roughened by, for example, sandblasting to form the rough surface portion 33 .
Next, a process (blow process) of inflating the laminated parison by supplying (blowing) pressurized air into the laminated parison is performed. As a result, the laminated parison can be pressed against the molding surface of the molding die, and the laminated parison can be molded in a shape corresponding to the molding surface. As a result, the extrusion blow container 1 shown in FIG. 1 can be formed.

Moreover, during the blowing process, the shape of the molding surface that has undergone roughening processing such as unevenness is transferred to the outer surface of the outer layer 20, so that the entire outer surface of the outer layer 20 can be roughened when the extrusion blow molding is performed. A face portion 33 can be formed. Therefore, the rough surface portion 33 can be formed without post-processing.
Since the rough surface portion 33 can be formed on the outer surface of the outer layer 20 when the extrusion blow molding is performed, the rough surface portion 33 is not formed on the parting line.

Therefore, the extrusion blow container 1 having the rough surface portion 33 can be manufactured when the extrusion blow molding is performed. Therefore, unlike the case where a metallic effect is imparted by painting, deposition, or the like, it is not troublesome, and cost reduction can be achieved. Therefore, it is possible to meet the need for cost reduction for containers, and the extrusion blow container 1 can be suitably used for various purposes such as containers for cosmetics.

As described above, according to the extrusion blow container 1 of the present embodiment, a container having a sufficient metallic effect can be obtained simply by performing extrusion blow molding.

Further, since the outer layer 20 is formed thinner than the inner layer 22, the visibility of the inner layer 22 can be improved. Moreover, since the coloring agent is contained in the first synthetic resin 30 at a concentration of less than 15% by weight with respect to the first synthetic resin 30, it is possible to prevent the coloring concentration of the outer layer 20 from becoming excessively high. , and the visibility of the inner layer 22 can be appropriately ensured. For these reasons, a good metallic feeling can be obtained.

In addition, since the outer layer 20 is mainly formed of PET resin, it is possible to provide the outer layer 20 with good light transmittance and, for example, toughness, gas barrier properties, chemical resistance, and the like. . Since the inner layer 22 is mainly made of PP resin, the inner layer 22 can have excellent heat resistance, mechanical properties, and the like. Therefore, the extrusion blow container 1 having a container main body 10 of stable quality can be obtained, in addition to being able to handle a wide variety of contents.

Moreover, since the innermost layer 23 is mainly formed of PP resin, it is possible to prevent the contents accommodated in the container body 10 from coming into contact with the metal powder 32 contained in the inner layer 22.例文帳に追加Therefore, it becomes possible to deal with a wider variety of contents.

In particular, in the extrusion blow container 1 of the present embodiment, since the rough surface portion 33 is formed on the entire outer surface of the outer layer 20, the outer surface can be made into a silk-like fine grain surface (textured surface) having fine unevenness. can. Therefore, the outer surface of the outer layer 20 can be formed semi-glossy. Therefore, rather than making the metallic effect stand out, it is possible to provide a moist and luxurious feeling while feeling the metallic effect. In other words, the extrusion blow container 1 can have a unique appearance having a metallic feel and a matte texture with a suppressed glossiness.
Therefore, it is effective when it is desired to create a container that has a matte texture that brings out a calm and luxurious feeling while giving a metallic feeling.

Next, an example in which the above-described extrusion blow container 1 is actually formed by extrusion blow molding will be described. However, the present invention is not limited to the following examples.

As the first synthetic resin 30 forming the outer layer 20, a PET resin (trade name: EB062, Haze: 1.3%, manufactured by Eastman Chemical Japan Co., Ltd.) was used. A blue coloring agent was added to the first synthetic resin 30 at a concentration of 8% by weight.
As the second synthetic resin 31 forming the inner layer 22, a PP resin (trade name: E233GV, haze: 15%, manufactured by Prime Polymer Co., Ltd.) was used. Aluminum powder having a particle size of 40 μm was used as the metal powder 32 . Then, 1% by weight of metal powder 32 was added to the second synthetic resin 31 .
As the synthetic resin constituting the innermost layer 23, PP resin (trade name: E233GV, haze: 15%, manufactured by Prime Polymer Co., Ltd.) was used, similarly to the second synthetic resin 31 .
As the adhesive layer 21, an adhesive resin (trade name: F503, manufactured by Mitsubishi Chemical Corporation) was used.

A laminated parison was formed by extrusion using each of the materials described above. At this time, the laminated parison was formed so that the thickness of the outer layer 20 was 90 μm, the thickness of the adhesive layer 21 was 60 μm, the thickness of the inner layer 22 was 690 μm, and the thickness of the innermost layer 23 was 30 μm. Next, after sandwiching the laminated parison using a molding die having a sandblasted molding surface, extrusion blow molding was performed to manufacture an extrusion blow container 1 .

As a result, just by performing extrusion blow molding, it is possible to obtain the extrusion blow container 1 in which the rough surface portion 33 is formed on the entire outer surface of the outer layer 20, and as shown in FIG. It was possible to actually produce an extrusion blow container 1 having a unique appearance with a matte texture that creates a high-class feeling.
Therefore, it has been confirmed that forming the rough surface portion 33 on the outer surface of the outer layer 20 is effective when it is desired to create a container that is desired to have a matte texture that creates a calm and luxurious feel.

Although embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. Embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. Embodiments and modifications thereof include, for example, those that can be easily imagined by those skilled in the art, those that are substantially the same, and those within an equivalent range.

For example, in the above-described embodiment, the outer layer 20 is a layer that forms the outer surface of the container body 10. However, for example, a transparent or translucent synthetic resin clear layer is formed on the outer surface of the outer layer 20, and the clear layer is formed on the outer surface of the container body 10. It may be a layer forming the outer surface of the . The clear layer can be formed by extrusion blow molding.

Furthermore, in the above-described embodiment, the first synthetic resin 30 constituting the outer layer 20 is mainly made of PET resin, and the second synthetic resin 31 constituting the inner layer 22 is mainly made of PP resin. However, it is not necessary to change it as appropriate.
For example, the first synthetic resin 30 forming the outer layer 20 may be mainly made of PP resin, like the second synthetic resin 31 . In this case, since the adhesion between the outer layer 20 and the inner layer 22 is improved, the adhesive layer 21 does not have to be interposed between the outer layer 20 and the inner layer 22 .

Furthermore, in the above-described embodiment, for example, an inner layer that is releasably laminated on the inner surface of the innermost layer 23 may be further provided, and the inner layer may be configured to be deformable in volume as the contents decrease. With such a configuration, the container body 10 can be used as a delamination container (delaminated bottle).

In the above-described embodiment, the metal powder 32 may have a particle size of 20 μm or more and 100 μm or less.

In this case, since the metal powder 32 having a large particle diameter of 20 μm or more is used, the visible light incident from the outside of the container body 10 is easily diffusely reflected using the metal powder 32 . Therefore, variations in glossiness are likely to occur due to changes in the incident angle of visible light, and variations in glossiness can be increased. Therefore, the metallic feeling can be emphasized while maintaining the matte texture, and the extrusion blow container 1 can have a unique appearance with a matte tone and enhanced glitter.
However, since the maximum particle diameter of the metal powder 32 is 100 μm, the molding conditions for extrusion blow molding can be satisfied, and the second synthetic resin 31 containing the metal powder 32 can be properly subjected to extrusion blow molding. It is possible to do Therefore, the extrusion blow molding can appropriately form the extrusion blow container 1 having the above-described unique appearance.

Furthermore, in the above embodiment, the metal powder 32 may have a particle size of 3 μm or more and less than 20 μm.

In this case, since the metal powder 32 having a small particle diameter of less than 20 μm is used, the visible light incident from the outside of the container body 10 is less likely to be diffusely reflected by the metal powder 32 . Therefore, it is easy to suppress variations in glossiness due to changes in the incident angle of visible light, and it is possible to suppress an increase in variation in glossiness. Therefore, the metallic appearance can be made uniform over the entire inner layer 22, and a smoother glossy appearance can be provided. Therefore, the extrusion blow container 1 can have a unique appearance in which both a calm metallic feeling and a smooth glossy feeling are compatible although the container has a matte tone.
However, since the minimum particle diameter of the metal powder 32 is set to 3 μm, it is possible to use the known metal powder 32 and to carry out the extrusion blow molding while appropriately containing the metal powder 32 in the second synthetic resin 31 . is. Therefore, the extrusion blow molding can appropriately form the extrusion blow container 1 having the above-described unique appearance.

DESCRIPTION OF SYMBOLS 1... Extrusion blow container 10... Container main body 11... Mouth part 13... Body part 14... Bottom part 20... Outer layer 22... Inner layer 23... Innermost layer 30... First synthetic resin 31... Second synthetic resin 32... Metal powder

Claims (9)

An extrusion blow container having a container body made of synthetic resin in which a mouth portion, a body portion and a bottom portion are connected in this order from top to bottom,
The container body is
an outer layer made of a first synthetic resin containing a colorant and having light transmittance;
an inner layer formed of a second synthetic resin having a lower light transmittance than the outer layer and disposed radially inward of the container body relative to the outer layer;
The second synthetic resin contains metal powder,
The inner layer has light transmittance because the second synthetic resin has light transmittance ,
An extrusion blow container , wherein at least a part of the outer surface of the outer layer is formed with a rough surface portion having a surface roughness rougher than that of the inner surface of the outer layer. The extrusion blow container of claim 1, wherein
The extrusion blow container, wherein the outer layer is thinner than the inner layer. In the extrusion blow container according to claim 1 or 2,
The extrusion blow container, wherein the container body is formed of the second synthetic resin and has an innermost layer disposed radially inward of the container body relative to the inner layer. In the extrusion blow container according to any one of claims 1 to 3,
The extrusion blow container wherein said colorant is contained in said first synthetic resin in a concentration of less than 15% by weight relative to said first synthetic resin. The extrusion blow container of claim 1 , wherein
The extrusion blow container, wherein the metal powder has a particle size of 20 μm or more. In the extrusion blow container of claim 5 ,
The extrusion blow container, wherein the metal powder has a particle size of 100 μm or less. The extrusion blow container of claim 1 , wherein
The extrusion blow container, wherein the metal powder has a particle size of less than 20 μm. The extrusion blow container of claim 7 , wherein
The extrusion blow container, wherein the metal powder has a particle size of 3 μm or more. An outer layer formed of a first synthetic resin containing a colorant and having light transmittance, and a second synthetic resin having a light transmittance lower than that of the outer layer and having light transmittance and formed from the outer layer An extrusion blow container having a synthetic resin container body in which a mouth portion, a body portion, and a bottom portion are continuously arranged in this order from top to bottom, and a light-transmitting inner layer disposed radially inward. A manufacturing method of
A parison forming step of forming a laminated parison by extrusion;
a mold clamping step of sandwiching the laminated parison between molding dies and arranging the laminated parison in a cavity of the molding die;
a blowing step of pressing the laminated parison against the molding surface of the molding die to form the extrusion blow container by supplying pressurized air into the laminated parison;
During the parison forming step, the laminated parison is formed in a state in which the second synthetic resin is impregnated with metal powder;
In the mold clamping step, by using the mold having the roughened molding surface as the molding mold, at least a part of the outer surface of the outer layer has a rougher surface than the inner surface of the outer layer. A method for manufacturing an extrusion blow container, characterized by forming a roughened surface portion .

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