JP7241655B2 - extrusion blow container - Google Patents

Description

The present invention relates to extrusion blow containers.

BACKGROUND ART In recent years, in order to differentiate products, etc., extrusion blow containers with a wide variety of shapes and appearances and excellent designs have begun to appear on the market. There is a need to provide a more creative appearance by imparting a metallic feel (metallic luster) to the extrusion blow container, which emphasizes such design, when it is used for cosmetics, for example. .
Known methods for imparting a metallic feel include, for example, a method using coating with a metallic pigment, and a method using vapor deposition of a metal-based vapor deposition film (see, for example, Patent Document 1 below).

JP 2016-101942 A

However, in the case of providing a metallic feeling by coating, vapor deposition, etc., 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 for cost reduction of containers.

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

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 colored The outer layer is formed of a first synthetic resin containing a coloring agent and is formed of a light-transmitting outer layer and a second synthetic resin having a lower colorant concentration than the outer layer, and the outer layer is formed of the container body. Covering from the outer surface side, the container body is formed of a light-transmitting coating layer and a third synthetic resin that has a higher haze value than the outer layer and the coating layer and contains metal powder, and is higher than the outer layer. and an inner layer disposed on the inner surface side of the container body, and the thickness of the inner layer is 50% or more and 90% or less of the thickness of the container body.

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 provided by the metallic luster effect using the reflected light of 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 haze value of the inner layer is higher than the haze values of the outer layer and the covering layer, the inner layer is more difficult to transmit visible light than the outer layer and the covering layer. Therefore, by allowing visible light to remain in the inner layer, the existence of the metal powder contained in the inner layer can be emphasized, and the metallic feeling can be deepened, and it has a smooth luster like silk. A texture with a silky feel can also be exhibited.
From the above, it is possible to obtain an extrusion blow container having a sufficiently metallic feeling.

Since the inner layer that mainly expresses a metallic feeling is formed of the third synthetic resin containing metal powder, the container body having the outer layer, the coating layer, and the inner layer is manufactured by extrusion blow molding for blow molding the laminated parison. At the time of formation, it is possible to provide a sufficient metallic feeling as described above. Therefore, unlike the case where painting, vapor deposition, or the like is performed to provide a metallic feeling, it does not take time and effort, 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.

Since the container body covers the outer layer from the outer surface side of the container body and is provided with a light-transmitting coating layer, for example, by adjusting the haze value of the coating layer, it is possible to expand the design range of the extrusion blow container. .
Since the thickness of the inner layer is 50% or more and 90% or less of the thickness of the container body, the thickness of the inner layer containing the metal powder is ensured to be large, and the haze value of the inner layer is the same as that of the outer layer and the coating layer. With the fact that the haze value is higher than the haze value of , it is possible to provide a deeper metallic feeling.
If the thickness of the inner layer is less than 50% of the thickness of the container body, it becomes difficult to provide a deeper metallic effect. may be difficult to manufacture.

A haze value of the coating layer may be 1.0% or more and 10.0% or less.

In this case, since the haze value of the coating layer is 1.0% or more and 10.0% or less, a unique appearance having a matte texture with suppressed gloss is provided while expressing a metallic feeling. be able to.
If the haze value of the coating layer is less than 1.0%, the gloss cannot be suppressed, and if the haze value of the coating layer exceeds 10.0%, the degree of fogging is too large, making it difficult to develop a metallic feeling.

A haze value of the coating layer may be higher than a haze value of the outer layer.

In this case, since the haze value of the coating layer is higher than the haze value of the outer layer, it is possible to reliably provide an appearance having a matte texture with reduced gloss.

The thickness of the outer layer may be thicker than the thickness of the covering layer.

In this case, since the outer layer containing the colorant is thicker than the covering layer, the outer layer can have a dark appearance.

The container main body may include a light shielding layer that has a light shielding property and is arranged closer to the inner surface of the container main body than the inner layer.

In this case, since the container body has a light-shielding property and is provided with the light-shielding layer disposed closer to the inner surface side of the container body than the inner layer, the light from the inner layer side is blocked by the light-shielding layer, and the metallic feeling that appears is deep. can have

The container body may include an inner coating layer disposed closer to the inner surface of the container body than the inner layer.

In this case, since the container body includes the inner coating layer disposed closer to the inner surface of the container body than the inner layer, the inner layer containing the metal powder is coated with the inner coating layer not containing the metal powder from the inside in the radial direction. As a result, the metal powder can be prevented from coming into contact with the contents inside the container body.
When the inner coating layer that does not contain metal powder is the layer that forms the inner surface of the container body, it is possible to reliably prevent the metal powder from coming into contact with the contents in the container body.

The third synthetic resin may contain a colorant.

In this case, since the third synthetic resin that forms the thickest inner layer in the container body contains the coloring agent, the amount of stretching during the blowing process is large and the thickness is thin in the container body. It is possible to ensure the color depth even at the corner portions, and to suppress the color unevenness of the entire container body.

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. 2 is an enlarged view of part II of FIG. 1, shown as a first embodiment according to the present invention; FIG. 1. It is a photograph which shows the external appearance of the trunk|drum vicinity in the extrusion blow container of FIG. FIG. 2 is an enlarged view of part II of FIG. 1 shown as a second embodiment according to the present invention;

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the extrusion blow container which concerns on this invention is described with reference to drawings.
As shown in FIG. 1, the extrusion blow container 1 of the present embodiment includes a bottomed cylindrical container body 10 made of synthetic resin and 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.

Examples of contents include cosmetics, foods, detergents, and pharmaceuticals. For example, cosmetics include milky lotions, serums, liquid soaps, skin creams, and the like, and foods include beverages, seasonings, and the like. However, 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, when viewed 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 threaded 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 length 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 thread portion 11a. When the cap is attached to the opening 11 by undercut fitting, the cap may be a hinged cap, for example. Mouth 11 may be fitted with a dispenser having a fitting cap.

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 extends 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 over the entire length in the container axis O direction. 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 capacity of the extrusion blow container 1 or the type of contents.
For example, the container body may be a rectangular bottle in which the trunk portion 13 has a rectangular shape in a cross-sectional view. The container body may have a body portion 13 whose diameter increases from the top to the bottom. A container body 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 may be used.

The container body 10 has a laminated structure in which a plurality of layers are stacked in the thickness direction of the container body 10 . As shown in FIG. 2, the container body 10 includes a coating layer 21, an outer layer 20, an inner layer 22, and a light shielding layer 23, which are laminated in this order from the outer surface side to the inner surface side of the container body 10. It is said that

The outer layer 20 is made of a first synthetic resin 30 containing a coloring agent and has optical transparency. The first synthetic resin 30 does not contain metal powder 32, which will be described later.
Specifically, the first synthetic resin 30 is a resin whose main material is random polypropylene. However, the first synthetic resin 30 only needs to contain the most random polypropylene, and may contain other synthetic resins or additives. Among random polypropylenes, the first synthetic resin 30 is a material with a relatively low degree of cloudiness (for example, product name: E233GV, haze: 15% (thickness: 1 mm), made of prime polymer). However, the material of the first synthetic resin 30 is an example, and may be changed as appropriate.
The thickness of the outer layer 20 is, for example, approximately 100 μm (approximately 13% of the thickness of the container body 10). However, the 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.
The 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 density can be adjusted according to the ratio of the two. It is possible. In this embodiment, the pearl pigment is added to the masterbatch at a concentration of about 10% by weight. The particle size of the pearl pigment is 5 μm to 60 μm.
The coloring agent is contained in the first synthetic resin 30 so as to have a concentration of less than 15% by weight (for example, a concentration of 5% by weight) with respect to the first synthetic resin 30 . However, the content of the coloring agent is an example, and may be changed as appropriate.

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

The outer layer 20 configured as described above is colored with a coloring agent and has light transmittance, so that the inner layer 22 can be visually recognized from the outside of the container body 10 through the outer layer 20. . The light transmittance required for the outer layer 20 is not particularly limited as long as it can transmit visible light. The haze value can be measured using a color difference meter (SZ-Σ80-OS manufactured by Nippon Denshoku Industries).

The coating layer 21 is a synthetic resin layer that forms the outer surface of the container body 10 . The covering layer 21 covers the outer layer 20 from the outer surface side of the container body 10 . The coating layer 21 is made of a second synthetic resin 34 having a lower colorant concentration than the outer layer 20 . The coating layer 21 is formed of a second synthetic resin 34 that does not contain a coloring agent and metal powder 32, which will be described later.

The coating layer 21 has optical transparency like the outer layer 20 , and the outer layer 20 can be visually recognized from the outside of the container body 10 through the coating layer 21 . The haze value of the coating layer 21 is 1.0% or more and 10.0% or less. The haze value of the covering layer 21 is higher than the haze value of the outer layer 20 . In addition, the haze value of the coating layer 21 may be less than or equal to the haze value of the outer layer 20 .

The thickness of the coating layer 21 is thinner than the thickness of the outer layer 20 . The thickness of the coating layer 21 is thinner than each thickness of the inner layer 22 and the light shielding layer 23 . The thickness of the coating layer 21 is the thinnest among the layers forming the container body 10 . The thickness of the coating layer 21 is, for example, approximately 20 μm (approximately 3% of the thickness of the container body 10).
Note that the thickness of the coating layer 21 is an example, and may be changed as appropriate. For example, the thickness of the covering layer 21 may be equal to or greater than the respective thicknesses of the outer layer 20 and the light shielding layer 23 .

The second synthetic resin 34 is a resin whose main material is block polypropylene. However, the second synthetic resin 34 only needs to contain the most block polypropylene, and may contain other synthetic resins or additives. The second synthetic resin 34 has the same main component as the first synthetic resin 30 forming the outer layer 20 . The covering layer 21 overlaps the outer layer 20 in close contact therewith.

The second synthetic resin 34 is a block polypropylene material with a relatively high degree of haze (for example, product name: BC8D, Haze: 90% (thickness: 1 mm), manufactured by Japan Polypropylene Corporation). The haze value of the coating layer 21 is relatively small because it is formed thin with the second synthetic resin 34 having a relatively high cloudiness degree.
Note that the material of the second synthetic resin 34 is an example, and may be changed as appropriate. For example, the main components of the second synthetic resin 34 and the first synthetic resin 30 may be different from each other, and an adhesive layer may be arranged between the coating layer 21 and the outer layer 20 .

At least part of the outer surface of the coating layer 21 is formed with a rough surface portion 33 that is rougher than the surface roughness of the inner surface of the coating layer 21 (the bonding surface with the outer layer 20).
In this embodiment, the rough surface portion 33 is formed over the entire outer surface of the coating layer 21 . However, the present invention is not limited to this case. need not be formed.
By forming the rough surface portion 33, the outer surface of the coating layer 21 is made into a silk-like fine grain surface (so-called embossed surface) having minute unevenness. The rough surface portion 33 is formed by the inner surface of the cavity of the molding die during extrusion blow molding.

The inner layer 22 is disposed closer to the inner surface of the container body 10 than the outer layer 20 and is made of a synthetic resin layer having light transmittance like the outer layer 20 and the coating layer 21 . The inner layer 22 is made of a third synthetic resin 31 having a higher haze value than the outer layer 20 and the coating layer 21 .

Specifically, the third synthetic resin 31 is a resin (for example, product name: B511QA, Haze: 30% (thickness: 1 mm), made by Prime Polymer) whose main material is primary color block polypropylene. However, the third synthetic resin 31 only needs to contain block polypropylene in the largest amount, and may contain other synthetic resins or additives. In addition, the inner layer 22 may have a light shielding property and may be opaque. The third synthetic resin 31 has the same main component as the first synthetic resin 30 forming the outer layer 20 . The inner layer 22 overlaps the outer layer 20 in close contact therewith.
Note that the material of the third synthetic resin 31 is an example, and may be changed as appropriate. For example, the main components of the third synthetic resin 31 and the first synthetic resin 30 may be different from each other, and an adhesive layer may be arranged between the inner layer 22 and the outer layer 20 .

The thickness of the inner layer 22 is, for example, around 600 μm. The thickness of the inner layer 22 is the thickest among the layers forming the container body 10 . The thickness of the inner layer 22 is 50% or more and 90% or less, preferably 65% or more and 85% or less of the thickness of the container body 10 . In this embodiment, the thickness of the inner layer 22 is approximately 78% of the thickness of the container body 10 . Note that the thickness of the inner layer 22 is an example, and may be changed as appropriate.

The third 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 3 μm or more and 100 μm or less (for example, 20 μm). The metal powder 32 is contained in the third synthetic resin 31 so as to have a concentration of, for example, 30% by weight with respect to the third synthetic resin 31 . Note that the particle size and content of the metal powder 32 are examples, and may be changed as appropriate.
The inner layer 22 is formed by extrusion blow molding a third 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 light shielding layer 23 is a layer that forms the inner surface of the container body 10 and is arranged closer to the inner surface of the container body 10 than the inner layer 22 is. The light shielding layer 23 is made of the fourth synthetic resin 35 . In this embodiment, the fourth synthetic resin 35 is the same as the third synthetic resin 31 of the inner layer 22 . The fourth synthetic resin 35 does not contain the coloring agent and the metal powder 32 . The light shielding layer 23 is a synthetic resin layer that overlaps the inner layer 22 in close contact therewith. Note that the material of the fourth synthetic resin 35 is an example, and may be changed as appropriate. For example, the main components of the fourth synthetic resin 35 and the third synthetic resin 31 may be different from each other, and an adhesive layer may be provided between the light shielding layer 23 and the inner layer 22 .
The thickness of the light shielding layer 23 is, for example, about 50 μm (about 6% of the thickness of the container body 10 ), which is thinner than the outer layer 20 and the inner layer 22 and thicker than the covering layer 21 . Note that the thickness of the light shielding layer 23 is an example, and may be changed as appropriate.

The fourth synthetic resin 35 contains a light shielding material.
The light shielding material includes a milky white masterbatch (for example, trade name: PPM-2KF868S-CRM-B-FD, manufactured by Toyocolor). However, it is not limited to this case, and for example, a masterbatch of gray or black may be used. The light shielding material is contained in the fourth synthetic resin 35 so as to have a concentration of, for example, 8% by weight with respect to the fourth synthetic resin 35 . In addition, the content of the light shielding material is an example, and may be changed as appropriate.

The light transmittance of visible light in the light shielding layer 23 is 10% or less, preferably 3% or less. In this embodiment, the light transmittance of visible light in the light shielding layer 23 is 0%.
The light transmittance can be measured by using an ultraviolet-visible-near-infrared spectrophotometer (Shimadzu UV-3150) in accordance with JIS K7375.

In the above configuration, of the plurality of layers forming container body 10 , at least light shielding layer 23 forming the inner surface of container body 10 does not contain metal powder 32 . In this configuration, it is preferable that the metal powder 32 is not contained in the light shielding layer 23 and the coating layer 21 forming the inner surface and the outer surface of the container body 10 among the plurality of layers constituting the container body 10 .
That is, the outer layer 20 and the coating layer 21 may contain the metal powder 32 .

A method for forming the extrusion blow container 1 by extrusion blow molding will be described below.

First, by extrusion molding, a cylindrical shape is formed by combining a first layer that becomes the coating layer 21, a second layer that becomes the outer layer 20, a third layer that becomes the inner layer 22, and a fourth layer that becomes the light shielding layer 23. to form a laminated parison (parison forming step).
Next, the laminated parison is sandwiched between molding dies and placed in the cavity (mold clamping step). At this time, an uneven portion for forming the rough surface portion 33 is formed on the inner surface of the cavity of the molding die. The concave-convex portion is formed by subjecting the inner surface of the cavity to roughening such as sandblasting.
Next, by supplying (blowing) pressurized air into the laminated parison, the laminated parison is inflated (blow process). As a result, the outer surface of the laminated parison is pressed against the inner surface of the cavity of the molding die, and the laminated parison is molded in a shape corresponding to the inner surface of the cavity to obtain the extrusion blow container 1 shown in FIGS.

Next, an embodiment of the extrusion blow container 1 will be described. However, the present invention is not limited to the following examples.

As the first synthetic resin 30 of the outer layer 20, random polypropylene (trade name: E233GV, Haze: 15% (thickness: 1 mm), made by Prime Polymer) was adopted. The first synthetic resin 30 contains a pearl pigment having a particle size of 5 μm to 60 μm at a concentration of 5% by weight with respect to the first synthetic resin 30 . The thickness of the outer layer 20 was set to 100 μm.
As the second synthetic resin 34 of the coating layer 21, block polypropylene (trade name: BC8D, Haze: 90% (thickness: 1 mm), manufactured by Japan Polypropylene Corporation) having a higher haze value than the first synthetic resin 30 was adopted. The thickness of the coating layer 21 was set to 20 μm.
As the third synthetic resin 31 of the inner layer 22, block polypropylene (trade name: B511QA, haze: 30% (thickness: 1 mm), made by Prime Polymer) having a higher haze value than the second synthetic resin 34 was adopted. Metal powder 32 was added to the third synthetic resin 31 at a concentration of 30% by weight with respect to the third synthetic resin 31 . Aluminum powder having a size of 20 μm×5 μm×5 μm was used as the metal powder 32 . The thickness of the inner layer 22 was set to 600 μm.
As the fourth synthetic resin 35 of the light shielding layer 23, block polypropylene (trade name: B511QA, haze: 30% (thickness: 1 mm), made by Prime Polymer) similar to the third synthetic resin 31 was adopted. A light shielding material (trade name: PPM-2KF868S-CRM-B-FD, manufactured by Toyocolor) is added to the fourth synthetic resin 35 at a concentration of 8% by weight with respect to the fourth synthetic resin 35, and the visible light in the light shielding layer 23 is was taken as 0%. The thickness of the light shielding layer 23 was set to 50 μm.

A laminated parison was formed by extrusion using each of the materials described above. At this time, the thickness of the first layer that will be the coating layer 21 is about 50 μm, the thickness of the second layer that will be the outer layer 20 is about 240 μm, the thickness of the third layer that will be the inner layer 22 is about 1420 μm, and the light shielding layer 23 and the A laminated parison was formed so that the fourth layer had a thickness of about 120 μm. Next, the extrusion blow container 1 was manufactured by molding the laminated parison as described above using a molding die having concave and convex portions formed on the inner surface of the cavity.

As a result, just by performing extrusion blow molding, it is possible to obtain the extrusion blown container 1 in which the rough surface portion 33 is formed on the entire outer surface of the coating layer 21, and as shown in FIG. It was possible to actually produce the extrusion blow container 1 having a unique appearance with a matte texture that creates a moist and luxurious feeling.
Therefore, it has been confirmed that forming the rough surface portion 33 on the outer surface of the coating layer 21 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.

As described above, according to the extrusion blow container 1 of the present embodiment, the inner layer 22 containing the metal powder 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 provided by the metallic luster effect using the reflected light from 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 has a higher haze value than the outer layer 20 and the covering layer 21 , the inner layer 22 is less likely to transmit visible light than the outer layer 20 and the covering layer 21 . Therefore, by allowing the visible light to remain in the inner layer 22, the existence of the metal powder 32 contained in the inner layer 22 can be emphasized, the metallic feeling can be deepened, and a silky smooth luster can be obtained. A texture with a silky feel can also be exhibited.
As described above, the extrusion blow container 1 can have a sufficiently metallic appearance.

Since the inner layer 22 that mainly expresses metallic feeling is formed of the third synthetic resin 31 containing the metal powder 32, the outer layer 20, the coating layer 21, and the inner layer 22 are formed by extrusion blow molding for blow molding the laminated parison. At the time when the container body 10 having the Therefore, unlike the case where painting, vapor deposition, or the like is performed to provide a metallic feeling, it does not take time and effort, 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.

Since the container body 10 covers the outer layer 20 from the outer surface side of the container body 10 and is provided with the coating layer 21 having light transmittance, for example, by adjusting the haze value of the coating layer 21, the design of the extrusion blow container 1 can be changed. width can be increased.
Since the thickness of the inner layer 22 is 50% or more and 90% or less of the thickness of the container body 10, the thickness of the inner layer 22 having the metal powder 32 is ensured to be large, and the haze value of the inner layer 22 is increased. , the haze value of the outer layer 20 and the covering layer 21 is higher than that of the outer layer 20 and the covering layer 21, so that a deeper metallic feeling can be provided.
If the thickness of the inner layer 22 is less than 50% of the thickness of the container body 10, it becomes difficult to provide a deeper metallic effect. Manufacturing of the blow container 1 may become difficult.

Since the haze value of the coating layer 21 is 1.0% or more and 10.0% or less, it is possible to provide a unique appearance having a matte texture with reduced gloss while expressing a metallic feeling. can.
If the haze value of the coating layer 21 is less than 1.0%, gloss cannot be suppressed, and if the haze value of the coating layer 21 exceeds 10.0%, the degree of fogging is too large, and it is difficult to develop a metallic feeling. Become.

Since the haze value of the coating layer 21 is higher than the haze value of the outer layer 20, it is possible to reliably provide an appearance having a matte texture with reduced gloss.
Since the outer layer 20 containing the colorant is thicker than the covering layer 21, the outer layer 20 can have a deep colored appearance.
Since the container body 10 has a light-shielding property and is provided with the light-shielding layer 23 disposed closer to the inner surface side of the container body 10 than the inner layer 22, the light from the inner layer 22 side is blocked, and the metallic feeling expressed has depth. can have.
Since the container body 10 is provided with the light shielding layer 23, deterioration of the contents due to light can be suppressed.

Since the inner layer 22 containing the metal powder 32 is sandwiched from both sides in the radial direction by the light shielding layer 23 and the coating layer 21 that do not contain the metal powder 32, the metal powder 32 is not exposed on the inner and outer surfaces of the container body 10. can be prevented, and the metal powder 32 can be prevented from coming into contact with the contents inside the container body 10, for example.
Since the light shielding layer 23 not containing the metal powder 32 is a layer forming the inner surface of the container body 10, the metal powder 32 can be reliably prevented from coming into contact with the contents inside the container body 10. - 特許庁

The present invention is not limited to the above-described embodiments, and can be modified as appropriate without departing from the scope of the invention.

For example, another layer may be arranged on the inner surface side of the container body 10 with respect to the light shielding layer 23 . As another layer, for example, a configuration may be adopted in which the layer is detachably laminated on the inner surface of the light shielding layer 23 and the volume is reduced and deformed as the content is reduced. With such a configuration, the container body 10 can be used as a delamination container (delaminated bottle).
The container body 10 may not have the light shielding layer 23 .

In the above embodiment, random polypropylene is used as the first synthetic resin 30 of the outer layer 20, but the present invention is not limited to this, and for example, block polypropylene, which generally has better impact resistance than random polypropylene, may be used. Among block polypropylenes, a material with a relatively low haze degree (for example, product name: CS356M, Haze: 11% (thickness: 1 mm), manufactured by SunAllomer) may be used.
The first synthetic resin 30, the second synthetic resin 34, the third synthetic resin 31, and the fourth synthetic resin 35 are not limited to polypropylene, and other synthetic resins such as high-density polyethylene may be employed.

In addition, it is possible to appropriately replace the components in the above-described embodiment with well-known components without departing from the gist of the present invention, and the above-described modifications may be combined as appropriate.

Next, an extrusion blow container 2 according to a second embodiment of the present invention will be described with reference to FIGS. 1 and 4. FIG.
In the second embodiment, the same reference numerals are assigned to the same components as in the first embodiment, the description thereof is omitted, and only the different points will be described.

In this embodiment, the container body 10 includes a coating layer 41 , an outer layer 40 , an inner layer 42 and an inner coating layer 43 .

The outer layer 40 is made of a first synthetic resin 50 containing a coloring agent and has optical transparency. The first synthetic resin 50 does not contain the metal powder 32 .
Specifically, the first synthetic resin 50 is a resin whose main material is block polypropylene. However, the first synthetic resin 50 only needs to contain the most block polypropylene, and may contain other synthetic resins or additives. The first synthetic resin 50 is a material with a relatively low cloudiness degree among block polypropylenes (for example, product name: CS356M, Haze: 11% (thickness: 1 mm), manufactured by SunAllomer). However, the material of the first synthetic resin 50 is an example, and may be changed as appropriate.
The thickness of the outer layer 40 is, for example, approximately 88 μm (approximately 8% of the thickness of the container body 10). However, the thickness of the outer layer 40 is an example, and may be changed as appropriate.

As a coloring agent, a masterbatch can be used as in the first embodiment. In this embodiment, the pearl pigment is added to the masterbatch at a concentration of about 10% by weight. The particle size of the pearl pigment is 5 μm to 60 μm.
The coloring agent is contained in the first synthetic resin 50 so as to have a concentration of less than 15% by weight (for example, a concentration of 5% by weight) with respect to the first synthetic resin 50 . However, the content of the coloring agent is an example, and may be changed as appropriate.

The outer layer 40 configured as described above is colored with a coloring agent and has light transmittance, so that the inner layer 42 can be visually recognized from the outside of the container body 10 through the outer layer 40. . The light transmittance required for the outer layer 40 is not particularly limited as long as it can transmit visible light.

The coating layer 41 is a synthetic resin layer that forms the outer surface of the container body 10 . The covering layer 41 covers the outer layer 40 from the outer surface side of the container body 10 . The coating layer 41 is made of a second synthetic resin 54 having a lower colorant concentration than the outer layer 40 . The coating layer 41 is made of a second synthetic resin 54 that does not contain the coloring agent and the metal powder 32 .

The coating layer 41 has optical transparency like the outer layer 40 , and the outer layer 40 can be visually recognized from the outside of the container body 10 through the coating layer 41 . The haze value of the coating layer 41 is 1.0% or more and 10.0% or less. The haze value of the covering layer 41 is higher than the haze value of the outer layer 40 . Note that the haze value of the coating layer 41 may be less than or equal to the haze value of the outer layer 40 .

The thickness of the coating layer 41 is thinner than the thickness of the outer layer 40 . The thickness of the coating layer 41 is thinner than each thickness of the inner layer 42 and the inner coating layer 43 . The thickness of the coating layer 41 is the thinnest among the layers forming the container body 10 . The thickness of the coating layer 41 is, for example, approximately 22 μm (approximately 2% of the thickness of the container body 10).
Note that the thickness of the coating layer 41 is an example, and may be changed as appropriate. For example, the thickness of the coating layer 41 may be equal to or greater than the respective thicknesses of the outer layer 40 and the inner coating layer 43 .

The second synthetic resin 54 is a resin whose main material is block polypropylene. However, the second synthetic resin 54 only needs to contain the most block polypropylene, and may contain other synthetic resins or additives. The second synthetic resin 54 has the same main component as the first synthetic resin 50 forming the outer layer 40 . The covering layer 41 overlaps the outer layer 40 in close contact therewith.

The second synthetic resin 54 is a block polypropylene material with a relatively high degree of haze (for example, product name: BC6D, Haze: 90% (thickness: 1 mm), manufactured by Japan Polypropylene Corporation). The haze value of the coating layer 41 is relatively small because it is formed thin with the second synthetic resin 54 having a relatively high cloudiness degree.
Note that the material of the second synthetic resin 54 is an example, and may be changed as appropriate.

The inner layer 42 is arranged closer to the inner surface of the container body 10 than the outer layer 40 and is made of a synthetic resin layer having light transmittance like the outer layer 40 and the coating layer 41 . The inner layer 42 is made of a third synthetic resin 51 having a higher haze value than the outer layer 40 and the coating layer 41 .

Specifically, the third synthetic resin 51 is a resin (eg, product name: B511QA, Haze: 30% (thickness: 1 mm), made by Prime Polymer) whose main material is primary color block polypropylene. However, the third synthetic resin 51 only needs to contain block polypropylene in the largest amount, and may contain other synthetic resins or additives. The third synthetic resin 51 has the same main component as the first synthetic resin 50 forming the outer layer 40 . The inner layer 42 overlaps the outer layer 40 in close contact therewith.
Note that the material of the third synthetic resin 51 is an example, and may be changed as appropriate.

The thickness of the inner layer 42 is, for example, around 942 μm. The thickness of the inner layer 42 is the thickest among the layers forming the container body 10 . The thickness of the inner layer 42 is 50% or more and 95% or less, preferably 65% or more and 90% or less, of the thickness of the container body 10 . In this embodiment, the thickness of the inner layer 42 is approximately 86% of the thickness of the container body 10 . Note that the thickness of the inner layer 42 is an example, and may be changed as appropriate.

The third synthetic resin 51 contains a coloring agent and metal powder 32 .
The coloring agent contained in the third synthetic resin 51 is of the same type as the coloring agent contained in the first synthetic resin 50 forming the outer layer 40 . The coloring agent is contained in the third synthetic resin 51 so as to have a concentration of, for example, 3% by weight with respect to the third synthetic resin 51 . The concentration of the colorant contained in the third synthetic resin 51 is lower than the concentration of the colorant contained in the first synthetic resin 50 .
The metal powder 32 is contained in the third synthetic resin 51 so as to have a concentration of, for example, 7% by weight with respect to the third synthetic resin 51 .
The visible light transmittance of the inner layer 42 is 10% or less, preferably 3% or less. In this embodiment, the third synthetic resin 51 contains both the coloring agent and the metal powder 32, and the thickness of the inner layer 42 is the thickest among the layers constituting the container body 10. The light transmittance of visible light in the inner layer 42 can be set to 0%.

The inner coating layer 43 is a layer that forms the inner surface of the container body 10 and is arranged closer to the inner surface of the container body 10 than the inner layer 42 is. The inner coating layer 43 is made of a fourth synthetic resin 55 . In this embodiment, the fourth synthetic resin 55 is the same as the third synthetic resin 51 of the inner layer 42 . The fourth synthetic resin 55 does not contain the coloring agent and the metal powder 32 . The inner coating layer 43 is a synthetic resin layer that overlaps the inner layer 42 in close contact therewith. Note that the material of the fourth synthetic resin 55 is an example, and may be changed as appropriate. For example, the main components of the fourth synthetic resin 55 and the third synthetic resin 51 may be different from each other, and an adhesive layer may be arranged between the inner coating layer 43 and the inner layer 42 .
The thickness of the inner coating layer 43 is, for example, about 44 μm (about 4% of the thickness of the container body 10 ), which is thinner than the outer layer 40 and the inner layer 42 and thicker than the coating layer 41 . Note that the thickness of the inner coating layer 43 is an example, and may be changed as appropriate.

In the above configuration, at least the inner coating layer 43 that forms the inner surface of the container body 10 does not contain the metal powder 32 among the plurality of layers that constitute the container body 10 . In this configuration, it is preferable that the inner coating layer 43 and the coating layer 41 forming the inner surface and the outer surface of the container body 10 among the plurality of layers constituting the container body 10 do not contain the metal powder 32 .
That is, the outer layer 40 and the coating layer 41 may contain the metal powder 32 .

Next, an embodiment of the extrusion blow container 2 will be described. However, the present invention is not limited to the following examples.

As the first synthetic resin 50 of the outer layer 40, block polypropylene (trade name: CS356M, Haze: 11% (thickness: 1 mm), manufactured by SunAllomer) was adopted. The first synthetic resin 50 contains a pearl pigment having a particle size of 5 μm to 60 μm at a concentration of 5% by weight with respect to the first synthetic resin 50 . The thickness of the outer layer 40 was set to 88 μm.
As the second synthetic resin 54 of the coating layer 41, block polypropylene (trade name: BC6D, Haze: 90% (thickness: 1 mm), manufactured by Japan Polypropylene Corporation) having a higher haze value than the first synthetic resin 50 was adopted. The thickness of the coating layer 41 was set to 22 μm.
As the third synthetic resin 51 of the inner layer 42, block polypropylene (trade name: B511QA, haze: 30% (thickness: 1 mm), made by Prime Polymer) having a higher haze value than the second synthetic resin 54 was adopted. The third synthetic resin 51 was made to contain a coloring agent at a concentration of 5.3% by weight with respect to the third synthetic resin 51 . The third synthetic resin 51 contains the metal powder 32 at a concentration of 7% by weight with respect to the third synthetic resin 51 . Aluminum powder having a particle size of 20 μm was used as the metal powder 32 . The thickness of the inner layer 42 was set to 942 μm.
As the fourth synthetic resin 55 of the inner coating layer 43, block polypropylene (trade name: B511QA, haze: 30% (thickness: 1 mm), made by Prime Polymer) similar to the third synthetic resin 51 was adopted. The thickness of the inner coating layer 43 was set to 44 μm.

A laminated parison was formed by extrusion using each of the materials described above. At this time, the thickness of the first layer to be the coating layer 41 is about 50 μm, the thickness of the second layer to be the outer layer 40 is about 200 μm, the thickness of the third layer to be the inner layer 42 is about 2000 μm, and the thickness of the inner coating layer 43 is about 2000 μm. A laminated parison was formed so that the thickness of the fourth layer, which was to be the fourth layer, was about 100 μm. Next, the extrusion blow container 2 was manufactured by molding the laminated parison as described above using a molding die having an uneven portion formed on the inner surface of the cavity.

As described above, according to the extrusion blow container 2 of the present embodiment, in addition to the effects of the extrusion blow container 1 according to the first embodiment, the inner layer 42 that is the thickest in the container body 10 is formed. Since the third synthetic resin 51 contains a coloring agent, the depth of color can be ensured even at the corners of the container body 10 where the amount of stretching during the blowing process is large and the thickness is thin. is possible, and color unevenness of the entire container body 10 can be suppressed.

Since the container body 10 is provided with the inner coating layer 43 disposed closer to the inner surface of the container body 10 than the inner layer 42, the inner layer 42 containing the metal powder 32 is the inner coating layer 43 and the inner coating layer 43 not containing the metal powder 32. It is possible to prevent the metal powder 32 from being exposed to the inner surface and the outer surface of the container body 10 by being sandwiched from both sides in the radial direction by the coating layer 41 , and the metal powder 32 can be prevented from being exposed to the contents inside the container body 10, for example. Avoid contact with objects.
Since the inner coating layer 43 that does not contain the metal powder 32 forms the inner surface of the container body 10, the metal powder 32 can be reliably prevented from coming into contact with the contents inside the container body 10. .

Since the content density of the colorant in the third synthetic resin 51 is lower than the content density of the colorant in the first synthetic resin 50 , the metal powder 32 contained in the third synthetic resin 51 utilizes the light reflected by the metal powder 32 . It is possible to prevent the effect of glossiness from weakening, and it is possible to reliably provide an appearance with a metallic sheen.

The present invention is not limited to the above-described embodiments, and can be modified as appropriate without departing from the scope of the invention.

For example, another layer may be disposed closer to the inner surface of the container body 10 than the inner coating layer 43 . As another layer, for example, a configuration may be adopted in which the layer is detachably laminated on the inner surface of the inner coating layer 43 and is capable of volume reduction and deformation as the contents decrease. With such a configuration, the container body 10 can be used as a delamination container (delaminated bottle).
Between the inner coating layer 43 and the inner layer 42, the light shielding layer 23 shown in the first embodiment may be provided. In this configuration, the light shielding layer 23 may contain the metal powder 32 .
The container body 10 may not have the inner coating layer 43 .

Although block polypropylene is used as the first synthetic resin 50 of the outer layer 40 in the above-described embodiment, it is not limited to this, and for example, random polypropylene may be used. Among block polypropylenes, a material with a relatively low haze degree (eg, trade name: E233GV, Haze: 15% (thickness: 1 mm), made by Prime Polymer) may be used.
The first synthetic resin 50, the second synthetic resin 54, the third synthetic resin 51, and the fourth synthetic resin 55 are not limited to polypropylene, and other synthetic resins such as high-density polyethylene may be employed.

In addition, it is possible to replace the components in the above-described embodiment with known components as appropriate without departing from the scope of the present invention, and the above-described first embodiment, second embodiment, and modifications Examples may be combined as appropriate.

DESCRIPTION OF SYMBOLS 1, 2... Extrusion blow container 10... Container main body 11... Mouth part 13... Body part 14... Bottom part 20, 40... Outer layer 21, 41... Coating layer 22, 42... Inner layer 23... Light shielding layer 30, 50... First synthetic resin 31, 51... Third synthetic resin 32... Metal powder 34, 54... Second synthetic resin 43... Inner coating layer

Claims (7)

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;
a light-transmissive coating layer made of a second synthetic resin having a colorant content lower than that of the outer layer and covering the outer layer from the outer surface side of the container body;
an inner layer having a haze value higher than that of the outer layer and the coating layer and formed of a third synthetic resin containing metal powder, and disposed closer to the inner surface of the container body than the outer layer;
The extrusion blow container, wherein the wall thickness of the inner layer is 50% or more and 90% or less of the wall thickness of the container body. 2. The extrusion blow container according to claim 1, wherein the coating layer has a haze value of 1.0% or more and 10.0% or less. 3. The extrusion blown container according to claim 1 or 2, wherein the haze value of the outer layer is lower than the haze value of the cover layer. 4. The extrusion blow container according to any one of claims 1 to 3, wherein the thickness of the outer layer is thicker than the thickness of the covering layer. 5. The extrusion blow container according to any one of claims 1 to 4, wherein the container body has a light-shielding property and is provided with a light-shielding layer disposed closer to the inner surface of the container body than the inner layer. 5. The extrusion blow container according to any one of claims 1 to 4, wherein the container body comprises an inner coating layer disposed closer to the inner surface of the container body than the inner layer. 7. The extrusion blow container of any one of claims 1-6, wherein the third synthetic resin comprises a colorant.

Images