JP2985677B2 - Colored liquid packaging - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a colored liquid plastic package having a specific decorative effect, that is, a cat's eye-like light reflecting effect.

[0002]

2. Description of the Related Art It is known to mix a pearl essence such as a mica titanium pigment in a plastic molded article to give the molded article a pearly luster, for example, in Japanese Patent Publication No. 43-2564.
No. 4 has been known for a long time, and many proposals have already been made regarding the application of this technology to hollow plastic containers.

[0003] For example, Japanese Patent Publication No. 53-41596 discloses an outer layer 2 formed of a transparent synthetic resin mixed with a predetermined amount of a pearl essence such as a mica-based or titanium-based material for providing a pearl decoration effect. A pearl decoration in which a main body 1 is constituted by an inner layer 3 formed of an opaque synthetic resin of a desired color laminated inside an outer layer 2 is described.

[0004] Japanese Patent Publication No. 59-44255 describes a container having a modified polyolefin resin as a decorative layer.

[0005]

The above-mentioned prior art has achieved some success in providing a deep and deep pearly luster on the outer surface of a plastic hollow container or the like. Although the pearl-like glossy container uses the interference of light by pearl essence, it has a refined but discreet decorative effect, and it is displayed in shops and the like,
Alternatively, when the user picks it up, he is not particularly satisfied with the decorative effect in that he is not particularly eye-catching and unattractive.

[0006] Accordingly, an object of the present invention is to provide a colored liquid plastic package having a decorative effect, ie, a cat's eye effect, which is completely different from that of the conventional pearlescent container.

Another object of the present invention is that when light is incident on the surface of a container, a line or band of interference color light appears on a highlight portion of the container, and the highlight portion and its peripheral portion are different from each other. Another object of the present invention is to provide a colored liquid plastic package having a different hue.

[0008]

According to the present invention, there is provided a transparent thermoplastic resin inner layer, and provided outside the inner layer ,
Orient the scale-like thin film with high refractive index in the surface direction of the container surface
And a transparent or translucent multilayer resin container as a whole including an interference layer made of a synthetic resin having a specific chromatic color and having transparency by light interference, and filled in the container. It consists of colored liquid contents, and light
When incident, high-brightness surface reflection on the surface reflection part of the container
Lines or bands of light and chromatic interference colors appear, and this surface reflection
Reflected light or transmitted light from the colored liquid appears in the periphery of the part,
Provided is a colored liquid package having a so-called “cat's eye” -like decorative two-color coloring effect in which reflected light or transmitted light from a colored liquid and a chromatic interference color from an interference layer are simultaneously viewed.

According to the present invention, a transparent thermoplastic resin inner layer and a flaky thin film having a high refractive index are formed in the direction of the surface of the container.
Oriented, including an interference layer made of a synthetic resin having a specific coloration selectively by light interference and made of a transparent synthetic resin, and a laminate including an outermost layer of a synthetic resin having a transparency as a whole, which is transparent or and translucent multilayered resin containers composed of a colored liquid contents filled in the resin vessel, container surface
When light is incident on the container, a bright surface
Lines or bands of surface reflection light and chromatic interference color light appear, and this table
Reflected light or transmitted light from the colored liquid is present around the surface reflection part.
Appear, the chromatic interference colors is visually simultaneously, colored liquid package having a decorative two-color development effect of the so-called "cat's eye" like is provided from the interference layer and the reflective light or transmitted light from colored liquid .

An interference layer selectively exhibiting a specific color is formed.
To align the scale-like thin film with a high refractive index in the surface direction of the outer layer.
It is preferable to develop an interference color by using the above scale.
Mica titanium pigment was used as the flaky thin film, and its mixing ratio was simply
2 to 300 mg / dm^TwoEspecially preferred
10 to 100 mg / dm^TwoAnd Also refraction
Multiple types of trees with different refractive indices
Using flakes of micro-multi-laminate of oil layer, mixing
0.1 to 250 mg / dm in unit area conversion ^Two, Special
Preferably 1 to 70 mg / dm^TwoAnd

Further, a transparent coating layer containing a predetermined amount of an ultraviolet absorber is preferably provided on the outer side of the multilayer packaging container in order to minimize yellowing of the interference layer.

When the outermost layer is provided, a propylene-ethylene random copolymer having a weight average molecular weight (Mw) in the range of 25 × 10 ^{4 to} 33 × 10 ⁴ and an ethylene content of 2 to 8% by weight is used as the outermost layer. It is preferable to use a polymer from the viewpoint of transparency and glossiness, and it is preferable that the outermost layer is smoothed by melting the container after molding.

As the outermost layer, a blend containing a continuous phase (A) composed of a propylene-based resin and a dispersed phase (B) composed of an ethylene-based resin in a volume ratio of A: B = 90: 10 to 55:45 is used. When used, a frosted appearance can be obtained at the same time.

When thermoplastic polyester is used as the resin constituting the interference layer and the inner layer or the outermost layer, the transparency and gloss of the container are excellent.

[0015]

FIG. 1 shows an example of a sectional structure of a multilayer packaging container according to the present invention. In FIG. 1, a wall 1 of the container comprises an interference layer 2 and an inner layer 3. The interference layer 2 is a continuous phase 4 of a thermoplastic resin.
And a flaky thin film which emits a chromatic color by interference of light dispersed therein, for example, a mica titanium pigment 5. On the other hand, the inner layer 3 is made of a transparent thermoplastic resin layer.

In FIG. 2 showing another example of the cross-sectional structure, an outermost layer 8 made of a transparent resin is provided on the outer surface of the interference layer 2.
Are provided, and the others are the same as those in FIG.

According to the present invention, a special decorative effect, that is, a cat's eye as shown in FIG. The effect is obtained. That is, in FIG. 3, when light is irradiated from the outer surface side of the hollow container 10,
The reflected or transmitted light 12,12 from the colored liquid content is visible throughout, while at the same time a line or band 11 of the reflected light of the interference color from the interference layer is superimposed on it in the center of the container. Will be recognized. This line of light or band 11
Is chromatic and brilliant, and the number of lines or bands is one or more depending on the number and position (viewing position) of light sources, but appears at the center of the container.

Referring to FIG. 4 for explaining the generation of interference chromatic color by the mica titanium pigment 5, the mica titanium pigment 5 is composed of a mica substrate 15 having a large aspect ratio and a fine particle deposition layer of titanium dioxide formed on the surface of the mica substrate. 16).

When a light beam enters the mica titanium pigment, the light beam that enters and reflects on the surface of the titanium layer 16 and the light beam that enters and reflects at the interface 17 between the titanium layer 16 and the mica substrate 15 interfere with each other. Produces light.

There is a certain relationship between the thickness of the titanium layer 16 and the chromatic color generated by the interference of light, and this relationship is as shown in Table 1 below.

[0021]

[Table 1]

In the present invention, a flaky thin film such as a mica titanium pigment is preferably oriented and present in the surface direction of the outer layer.
This makes it possible to emphasize chromatic interference colors that are clear and bright.

FIG. 7 is a sketch based on a micrograph showing the dispersion state of the mica titanium pigment dispersed in the outer layer resin in Example 1, and the line length in the figure is 10 μm. From FIG. 7, the titanium mica pigment particles are on the resin surface (paper surface).
The fact that they are preferentially oriented becomes clear.

On the other hand, the inner layer 3 is formed of a transparent thermoplastic resin, and transmits reflected light and transmitted light from the colored liquid contents.

In the multilayer container of the present invention, the appearance of the cat's-eye decoration effect as shown in FIG. 3 was found as a phenomenon, and the reason for this has not yet been clarified yet. They estimate as follows.

That is, FIG. 5 for explaining this decorative effect.
, Each symbol has the following meaning. In FIG. 5, the transparent inner layer is omitted to avoid complication. Explanation of two-color coloring such as "cat's eye"-Explanation of symbols A: incident light B: surface reflected light (highlight) C: interference light (color) D: diffusely reflected light or transmitted light (coloration of colored liquid contents) E: Absorbed light x: Line-of-sight direction 8: Surface gloss layer 2: Interference layer 3: Inner layer 5: Interference-coloring type mica titanium oxide foil 5a, 5b: Mica titanium oxide foil oriented in a direction different from the line-of-sight direction 6: Coloring Liquid content-Explanation of two-color vision The incident light A is specularly reflected on the surface of the glossy layer 1 and becomes surface reflected light B which becomes strong highlight light. Since the surface reflected light B is a strong highlight, it is viewed more preferentially than the colored light D ′ of the liquid content 6. The incident light A is reflected in multiple layers by the mica titanium oxide foil 5 of the intermediate layer (interference layer) 2 and emits an interference color C. Since the brightness of the interference color C is high, the interference color C is seen preferentially over the colored light D ″ of the liquid content 6. Further, the interference color C of the mica titanium foils 5a and 5b oriented in a direction different from the viewing direction x. Are not seen from the line of sight x. The interference colors (red,
Coloring of the liquid content 6 that is visible through the substantially transparent intermediate layer 2, the substantially transparent mica titanium foil 5 and the surface gloss layer is visible in the portions other than the colored portion of the specific colored light (C) such as blue and yellow. .

FIG. 6 shows, using an integrating sphere, wavelengths of 300 to 1000 for each of the containers each having an interference layer made of a resin composition containing mica titanium pigments exhibiting yellow, blue and red interference colors, respectively.
It is a graph which shows the result of having measured the diffuse reflection spectral characteristic of nm, and it is clear that the interference color characteristic of each pigment actually appears.

As described above, according to the package of the present invention, an extremely clear and brilliant cat's eye effect can be obtained, and the decorativeness and commercial value of the colored liquid package can be enhanced.

According to one embodiment of the present invention, the above-mentioned mica-like titanium pigment is used as a scale-like thin film that produces interference colors. In this case, as the mica-like titanium pigment, one that produces a certain chromatic color, for example, a certain chromatic interference color such as red, blue, and yellow, should be used. Should be as constant as possible.

In the multilayer container of the present invention, the weight of the titanium mica pigment per unit area of the outer layer is 2 to 300 mg as described above.
/ Dm ² , especially in the range of 10 to 100 mg / dm ² . The reason why the abundance of the mica titanium pigment is defined by the weight per unit area is that this expression form most appropriately represents the multiplicity of the pigment in the layer thickness direction.

That is, whether the amount is larger or smaller than the above range, the cat's eye effect tends to be reduced as compared with the case where the amount is in the above range.

Needless to say, the scale-like thin film for interference colors used in the present invention is not limited to mica titanium pigment as long as it generates interference colors. As a preferable example of such a flaky thin film, a flake of a micro-multilayer laminate of a plurality of types of resin layers having different refractive indexes can be used. The flakes are of a size that can be visually identified by the flakes, and since the flakes are a mixture of hues having interference colors such as red, blue, and yellow, when mixed in the interference layer resin, A unique cat's eye effect (playing color effect) studded with different chromatic interference colors is obtained.

The multilayer container package of the present invention comprises the scaly flake-containing interference layer and the transparent resin inner layer as essential constituent layers, but may contain any other layers. For example, on the mica titanium pigment-containing interference layer, further providing a coating layer, particularly a thermoplastic resin layer with excellent transparency, and a UV-absorber-containing resin coating layer that prevents yellowing of the resin and the like, A sustained cat's eye effect is obtained.

As the outermost layer, gloss (JIS K7
105, incident angle 60 °) By using a thermoplastic resin layer of 8% or less, that is, a mat layer, it is possible to impart a good blurred luster to the product.

As the outermost layer, gloss (JIS)
K7105, incident angle 60 °) 70% or more, especially 80%
By using the above-mentioned thermoplastic resin layer, that is, a super gloss layer, clear gloss can be provided.

The color development of the interference layer is due to interference of light, so that it is difficult for the interference layer to discolor. Further, since the interference layer is shielded from the contents by the inner layer, discoloration and discoloration by the contents are hard to occur. Therefore, the container of the present invention has an advantage that a sustained decorative effect can be obtained.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The multilayer resin container used in the present invention comprises an interference layer made of a thermoplastic synthetic resin mixed with flaky flakes emitting a chromatic color due to light interference, a transparent thermoplastic synthetic resin inner layer, if necessary. It consists of a laminate with the outermost layer of a transparent thermoplastic resin provided on the interference layer.

An interference layer which emits a specific chromatic color and has transparency cannot be realized by using ordinary pigments and dyes. In this case, the color is a reflection color to the last and cannot be seen simultaneously with the reflection color of the inner layer, and is always a mixture of the reflection color of the inner layer and the reflection color of the outer layer. This color mixture is visible on the entire container wall and does not change depending on the viewing angle. For this reason, a scaly thin film, that is, a pearl essence, is preferably incorporated in the outer layer.

[Scaly Thin Film] A mica titanium pigment is preferably used as a scaly thin film to be included in the interference layer to generate a chromatic color by light interference. Pearl essence can be used. The mica titanium pigment is mica (3Al ₂ O ₃ .K ₂ O
A flaky crystal of (6SiO ₂ .nH ₂ O) is used as a nucleus, and a titanium oxide hydrate is precipitated on the nucleus and calcined to obtain titanium dioxide. The titanium dioxide layer on the surface may be an anatase type or a rutile type.

Mica is a flaky crystal having a cleavage property, a thickness of 1 μm or less, and a large aspect ratio of 50 or more, and a thin layer of titanium pigment having a large refractive index is formed on the surface thereof. Is formed, chromatic interference colors as shown in Table 1 can be obtained according to the layer thickness.

As other pearl essences, fish scale foil or flakes of resin micro multi-layered product can be used. The latter micro-multi-layered product is obtained by laminating a plurality of resins having different refractive indexes, for example, an acrylic resin and a polyester resin in a multi-layered manner with a micro thickness.
It is manufactured by the method described in JP-A-78323. The thickness of the flakes is 5 to 50 μm and the size of one side is about 0.1 to 0.5 mm. This micromultilaminate flake is commercially available from The Dow Chemical Company.

[Resin] As the resin, any thermoplastic resin used in this type of packaging container, for example, olefin resin, styrene resin, ABS resin, polyester resin, polyamide resin, nitrile resin, Examples thereof include vinyl chloride resins and polycarbonate resins.

Of these resins, thermoforming is easy, and
Moreover, it is an advantage of the present invention that an excellent decorative effect can be imparted to a general-purpose olefin-based resin which is advantageous also in terms of production cost. As the olefin resin, low-, medium- or high-density polyethylene, isotactic polypropylene, linear low-density polyethylene, ethylene-propylene copolymer, polybutene-1, ethylene-butene-1
Copolymer, propylene-butene-1 copolymer, ethylene-propylene-butene-1 copolymer, ethylene-vinyl acetate copolymer, ion-crosslinked olefin copolymer (ionomer), ethylene-acrylate copolymer Alternatively, a blend of these may be used, and among them, blow molding grade, extrusion molding grade, and injection molding grade are used according to the molding method.

Among these olefin resins, the propylene-based resin has better surface gloss, lower internal haze and excellent transparency as compared with other olefin resins. It is suitable as. As the propylene-based resin, in addition to homopolypropylene, propylene and other α-olefins, for example, ethylene, butene-1,
Copolymers with pentene-1, hexene-1 and the like, especially copolymers with ethylene, for example, random or block copolymers can be mentioned.

The resin for forming the interference layer has a weight average molecular weight (Mw) of 25 × 10 ^{4 to} 33 × 10 ⁴ , particularly 29 × 10 ⁴ .
10 ⁴ to olefin resin in the range of 32 × 10 ^4,
Particularly, it is preferable to use a propylene-based resin. The weight average molecular weight can be determined by obtaining a molecular weight distribution curve using gel permeation chromatography and calculating the weight average molecular weight by universal calibration using polystyrene as a standard. Also,
Propylene-based copolymers, especially propylene-ethylene / random copolymers having the above-mentioned weight average molecular weight are suitable for this purpose. The random copolymer has an ethylene content of 2 to 8% by weight, particularly 3 to 5% by weight.
% By weight is suitable.

The titanium mica pigment is generally used in an amount of from 0.2 to 10% by weight, especially from 1 to 3% by weight, based on the resin constituting the outer layer.
It is good to mix in the amount of. That is, when the amount is less than the above range, the expression of the cat's eye effect is not sufficient, while when the amount is more than the above range, the expression of the cat's eye effect is also insufficient.

In the production of the resin composition for the outer layer, vigorous mixing and kneading such that the fine structure of the mica titanium pigment is destroyed should be avoided. For this purpose, a masterbatch containing a relatively high concentration of mica titanium pigment was manufactured,
This master batch is preferably kneaded with the resin for forming the outer layer and used for molding.

As the resin for forming the inner layer (base layer), any of the resins described for the resin for forming the outer layer may be used.
As the thermoplastic resin for forming the inner layer, a resin having transparency is used. In general, as the resin for forming the inner layer, a resin having a small unevenness and a low drawdown property is used in terms of blow moldability and the like, and among the above-mentioned olefin resins, those satisfying the above requirements are used.

As the inner layer resin, a propylene resin, in particular, a homopolypropylene or the above-mentioned propylene copolymer is used. The content of propylene units in the whole polymer is 85 mol% or more, especially 90 mol% or more, and 10 g when the melt flow rate (MFR) is polypropylene.
/ 10 minutes or less is desirable. Further, as another example of the polyolefin resin constituting the inner layer, a high-density polyethylene having an MFR of 2 g / 10 minutes or less can be used.

As the resin for forming the outermost layer to be used as desired, those described for the resin for forming the interference layer and the thermoplastic resin for forming the inner layer, and other resins are used. Generally, the outermost layer resin is preferably one having excellent transparency.

As a suitable example of the outermost resin layer, a thermoplastic resin layer having a gloss (JIS K7105, incident angle of 60 °) of 8% or less, particularly 6% or less, that is, a mat layer can be used. Good blur gloss or waxy gloss can be provided. Further, as another example of the outermost layer, a thermoplastic resin layer having a gloss of 70% or more, particularly 80% or more, that is, a super-gloss layer can be used, thereby providing a clear gloss. Of course, the outermost layer is not limited to this example.

A suitable example of the mat layer resin is a blend of a propylene-based continuous phase-forming resin (A) and an ethylene-based dispersed phase-forming resin (B). In general, it is preferable that A: B = 90: 10 to 55:45, especially 85:15 to 60:40 in volume ratio. Further, it is advantageous that the continuous phase-forming resin (A) has a higher melting point or softening point than that of the dispersed phase-forming resin (B) from the viewpoint of giving a frosted appearance.

As the propylene resin, a homopolymer of propylene, a random or block copolymer of propylene with other olefins, for example, ethylene, butene-1, 2-methylpentene-1, and the like are used. You.
The propylene-based polymer can be used alone or in combination of two or more. The propylene content of the propylene-based polymer is desirably 90% by weight or more. As the propylene-based polymer, an ethylene-propylene block copolymer is particularly preferred, and generally comprises a homopropylene polymerization block and an ethylene-containing polymerization block bonded thereto. The ethylene-containing polymer block may be composed of a homopolyethylene block of ethylene alone or a random copolymer block of ethylene and propylene mainly composed of ethylene. In short, ethylene in the ethylene-containing block
It may be contained in an amount of 3 to 10% by weight.

On the other hand, examples of the ethylene-based polymer include low-density, medium-density and high-density polyethylenes and linear low-density to medium-density copolymers of ethylene and a small amount of other α-olefin. High-density polyethylene or a copolymer of ethylene and another monomer such as a vinyl-based or acrylic-based monomer, such as ionomer, EVA, or EEA is used. Ethylene polymers can be used alone or in combination of two or more. Further, the ethylene content of the ethylene-based polymer is desirably 90% by weight or more.

Examples of the resin capable of forming the super-gloss layer include ethylene-propylene / random copolymers, and preferred are those having an ethylene content of 2 to 8% by weight, particularly 3 to 5% by weight. %, The weight average molecular weight (M
There is a propylene-ethylene random copolymer in which w) is in the range of 25 × 10 ^{4 to} 33 × 10 ⁴ . This outermost layer is smoothed by a container melting treatment after molding, as described later.

In order to minimize yellowing of the outer layer, a predetermined amount of an ultraviolet absorber can be added to the outermost layer.

[Laminated Structure] In the present invention, the laminated structure of the container contains the interference layer, the inner layer or the outermost layer. However, other layers may be included in addition to these layers. For example, it should be understood that various functional layers may be provided as intermediate layers between the interference layer and the inner layer.

For example, an intermediate layer of a gas barrier resin can be provided between the interference layer and the substrate via an adhesive resin layer.

That is, a gas barrier resin can be incorporated into the multilayer structure in order to impart gas permeability resistance to oxygen and the like to the formed container. Generally, the gas barrier resin has an oxygen permeability coefficient (PO ₂ ) of 5.5 ×.
10 ^-12 cc · cm / cm ² · sec · cmHg or less, especially 4.5 × 10
Ethylene-vinyl alcohol copolymer having an ethylene content of 20 to 50 mol% and an unsaponified vinyl ester residue content of 5 mol% or less at ^-12 cc · cm / cm ² · sec · cm Hg or less Or 3 amide groups per 100 carbon atoms
Homopolyamides, copolyamides or blends thereof containing from 30 to 30, especially from 4 to 25 are preferably used. Of course, the above-mentioned ethylene-vinyl alcohol copolymer and polyamide can be used in the form of a blend, and other thermoplastics can be used within a range that does not impair the essence thereof, for example, within a range of 20% by weight or less. It is also possible to use a resin, for example, a polyolefin or a resin that imparts adhesion between the polyolefin and the like.

An oxygen absorbent-containing resin layer, a desiccant-containing resin layer, or the like can be provided as an intermediate layer in place of or in addition to the above-mentioned intermediate layer. (Resin) may be used as an intermediate layer for reuse.

In the multilayer container of the present invention, the thickness ratio of the interference layer to the thickness of the entire vessel wall is preferably 1 to 30%, particularly 5 to 20%, and the minimum thickness is preferably 30 μm or more. When the thickness is smaller than the lower limit, the cat's eye effect is not sufficiently obtained. On the other hand, when the thickness is larger than the upper limit, the cat's eye effect is still insufficient, and the blow moldability of the container is further reduced. However, it is disadvantageous in terms of cost. The thickness of the entire vessel wall varies depending on the application and the location of the container, and cannot be specified unconditionally.
It is preferably in the range of 00 to 1500 μm.

The thickness of the outermost layer provided on the mica titanium pigment-containing layer is generally preferably in the range of 20 to 300 μm.

According to the present invention, according to the present invention, the resin for forming the inner layer is used as the base, the resin for forming the interference layer is used as the outer layer, and the outermost resin is used as the outermost layer, if necessary. And molded into a multilayer resin container. Of course, when an intermediate layer or an adhesive resin layer is interposed between the base and the interference layer, these resins are also laminated at the same time.

For the production of the multilayer laminate, a coextrusion method, a co- or sequential injection method, an extrusion coating method, a sandwich lamination method and the like can be used. That is, the multilayer packaging container of the present invention can be manufactured into a bottle-shaped or tube-shaped container by melt-extruding a multilayer parison and blow-molding the same in a split mold. Further, a cup-shaped container can be manufactured by forming a multilayer sheet by melt extrusion and then subjecting the sheet to vacuum forming, air pressure forming, plug assist forming, or the like. Also, a tubular container can be manufactured by extrusion tube molding.

The production method is not limited to these methods, and it is also possible to produce a preform by a co-injection molding method and then blow-mold this to produce a stretched multilayer bottle. Similarly, injection multilayer packaging containers such as caps and jars can be manufactured by the two-color molding method.

The blow molding of a typical bottle will be described. In co-extrusion, a plurality of extruders corresponding to the type of resin are used, and a plurality of molten resin streams are merged in a multi-layered multi-die, and the molten resin flows out of the die. Extrude into A circular die is used as the die, and the extrusion temperature is a temperature not lower than the higher melting point of the resin used and not higher than the decomposition temperature. In the case of a propylene-based resin, it is generally 180 to 230.
A temperature of ° C is appropriate.

If the extrusion temperature is too high, the drawdown tendency of the parison becomes remarkable, while if it is too low, shark skin tends to occur due to melt fracture. Generation of drawdown, flow mark, and shark skin can be prevented.

The extruded parison is then blow molded in a blow mold having a sandblasted surface while it is still in a molten state. This blow molding is generally performed by using a pair of split dies having a parting surface, pinching off the parison with the split die, and injecting a pressurized fluid into the confined parison. By using a blow mold having a sandblasted surface, the interference layer can be processed to a matte (matte) tone to add a good waxy luster to articles such as the inside of alabaster or shells. The average depth roughness of the outer layer is preferably in the range of 5 to 30 μm.

The cavity surface of the blow mold is a sand blast surface in order to prevent the molded resin from sticking to the mold cavity surface and to effectively release air between the mold surface and the resin surface. However, the particle diameter of the glass beads used for sandblasting is desirably in the range of 50 to 500 μm, particularly 75 to 200 μm from the above viewpoint.

As the pressurized fluid used for blow molding, pressurized air is generally used, but if desired, an inert gas such as nitrogen, water vapor, or other fluids can be used, and the pressure is 4 to 10 kg / cm. ^It should be at ² (gauge). Further, the blow mold can be forcibly cooled with cooling water or the like.

The blow molding is not particularly limited, but is preferably performed using a rotary molding machine in terms of efficiency. In this rotary molding machine, a number of split dies are arranged and provided around the rotary molder, and the split dies are provided so as to be rotatable in a certain direction and openable and closable. From the die head, the thermoplastic resin parison is extruded tangentially to the locus of the center of the split mold. At this tangential position, the split mold is open, and the supplied parison is sandwiched by the split mold to perform blow molding. . After blow molding, the split mold is opened and the molded product is released.

In the case of forming a super gloss outermost surface layer, after being melt-extruded into a parison, it is blow-molded in a blow mold having a sand blast surface while it is still in a molten state. Immediately after molding, the outermost surface of the blow molded product is subjected to heat melting treatment. This surface melting treatment is for smoothing by eliminating irregularities on the outermost surface of the blow molded product corresponding to the irregular pattern on the sandblast surface of the mold. Although any known heating means can be used for the heat treatment, flame (flame) treatment is excellent in that the mechanism is simple and the outer surface can be efficiently heated in a short time.

It is important that the flame treatment is performed in the state of a complete reducing flame so as not to cause combustion or oxidation of the molten parison. As a fuel, city gas, propane gas, liquefied natural gas, liquefied petroleum gas, etc. Any fuel gas is used. In the present invention, the temperature of the outermost surface of
It has been found that heating to 0 ° C. or higher, particularly 800 ° C. or higher is useful for improving the glossiness of the surface layer portion, and has no effect at 500 ° C. or lower. The temperature of the flame used is not particularly limited as long as the surface layer reaches the above-mentioned temperature, but a temperature of about 1600 ° C. is suitable as an example. The heating time may be an extremely short time for the blow molded product to pass through the burner. If the outermost surface of the blow molded product reaches the above temperature, it can be said that the heat treatment is sufficient.

[Liquid Content] In the present invention, by filling the above-mentioned multilayer resin container with the colored liquid content, a decorative two-color effect such as “cat's eye” can be exhibited. The degree of coloring of the liquid content may be relatively light color and recognized as transmitted light, or relatively dark color and recognized as reflected light. Needless to say, in the present specification, the term “coloring” also includes white reflected light, and the coloring may be performed by the content itself or by adding a pigment or a dye.

The liquid contents include toiletries such as shampoo, rinse, treatment, liquid soap, toothpaste, etc .; cosmetics such as hair cream, lotion, emulsion, lotion, hair tonic, cheving cream, hair liquid, etc .; shoes Daily necessities such as cream, liquid detergent, liquid wax; soy sauce, various sauces, tentsuyu, various sauces,
Liquid seasonings such as soup stock, dressing and mayonnaise; spirit drinks such as whiskey, brandy, rum, beer, red wine, various cocktails; beverages such as cola, juice, lactic acid bacteria drinks, yogurt; various liquid pharmaceuticals; Is exemplified.

It should be understood that the viscosity of the liquid content may be as high as possible, as long as it can be filled in the multilayer resin container.

[0077]

The present invention will be described with reference to the following examples. Although the liquid content in the embodiment is white, the color is not limited to white and may be any color. Further, the effects of the present invention can be obtained with a transparent liquid or an opaque liquid.

Example 1 As an outer layer, 2% by weight of mica titanium pigment (light yellow) was blended, ethylene content 4%, weight average molecular weight 30 × 10 ⁴
Is supplied to an extruder for an interference layer (outer layer), and as an inner layer, a propylene-ethylene block copolymer having an MI of 1.5 is supplied to an extruder for an inner layer. C. Two layers of molten parison were formed at a temperature of .degree. The surface of this molten parison was smooth without shark skin or flow marks.

This parison was blow-molded in a blow mold in which the inner surface of the mold was blasted with glass beads having a particle size of 180 μm to 75 μm to prevent air trapping, and the average thickness was 800 μm as shown in FIG. Content 500c
c and a two-layer bottle having an outer layer thickness of 50 μm.

The bottle after molding was filled with a white-colored liquid content, sealed, and observed under irradiation of light. As shown in FIG. 2, the periphery was white and the center was brilliant yellow. Excellent cat's eye effects were obtained.

Example 2 2% by weight of a pale blue mica titanium pigment for the outer layer was used.
A bottle was formed in the same manner as in Example 1 except for blending. The bottle after molding was filled with a liquid content colored white, sealed, and observed under irradiation of light. As a result, as shown in FIG. 2, the periphery was white and the center was brilliant light blue. Excellent cat's eye effect was obtained.

Example 3 As the outermost layer, an ethylene-propylene random copolymer having an ethylene content of 4% and a weight average molecular weight of 30 × 10 ⁴ containing 0.05% by weight of a benzotriazole ultraviolet absorber was used for the outermost layer. A bottle was formed in the same manner as in Example 1 except that the bottle was supplied to an extruder and a three-layer multiple die was used. The thickness of the outermost layer was 60 μm.

The molded bottle was filled with a white colored liquid content, sealed, and observed under light irradiation. As shown in FIG. 2, the periphery was white and the center was brilliant yellow. Excellent cat's eye effects were obtained.
In addition, this bottle was excellent in persistence of the cat's eye effect.

Example 4 As the outermost layer, an ethylene content of 4% and a weight average molecular weight of 2
An ethylene-propylene random copolymer of 7.1 × 10 ⁴ is supplied to the outermost layer extruder, and as an interference layer (outer layer), 2% by weight of a mica titanium pigment (light yellow) is blended, and the ethylene content is 4%. A propylene-ethylene random copolymer having a weight average molecular weight of 30 × 10 ⁴ was supplied to an extruder for an outer layer, and as an inner layer, an ethylene-propylene block copolymer having an MI of 1.1 was supplied to an extruder for an inner layer. At a resin temperature of 190 ° C., three layers of molten parison were formed.

In order to prevent air traps and fusion, this parison has a mold inner surface having a particle size of 180 μm to 7 μm.
Blow molding is performed in a blow mold blasted with 5 μm glass beads, and the average thickness is 950 μm, the internal capacity is 150 ml, and the thickness of the outermost layer and the outer layer is 5 as shown in the figure.
Three-layer bottles of 0 μm and 60 μm were formed. The 60 ° gloss at this time was 52%.

[0086] The outermost surface of the blow-molded product thus formed was subjected to a melting treatment to eliminate the uneven pattern corresponding to the sand blast surface of the mold, and was smoothed. As a result,
The 60 ° gloss was improved to 80%. After filling the bottle with the liquid content colored white, sealing it, and observing it under irradiation of light, the periphery is white, the center is brilliant yellow, the desired gloss is, the depth is A certain cat's eye effect could be exhibited.

As the outermost layer, a weight average molecular weight of 36 × 10
^When the propylene-ethylene random copolymer of No. ⁴ was used, shark skin tended to be generated on the surface of the molten parison, and the weight average molecular weight was 22 as the outermost layer.
When a × 10 ⁴ propylene-ethylene random copolymer was used, a tendency to generate flow marks was observed.

Example 5 As the outermost layer material, an ethylene-propylene random copolymer having an ethylene content of 4% and a weight-average molecular weight of 30 × 10 ⁴ containing 0.05% by weight of a benzotriazole type ultraviolet absorber, an outer layer material A propylene-ethylene random copolymer having an ethylene content of 4% and a weight average molecular weight of 30 × 10 ⁴ containing 2% by weight of a mica titanium pigment (light yellow), and an ethylene-propylene · MI of 0.6 as an inner layer. Using a block copolymer, an extruder for the outermost layer with a diameter of Φ35, an extruder for the outer layer with a diameter of Φ35, an extruder for the inner layer with a diameter of Φ75, a three-layer three-layer feed block, a T-die, a vertical three rolls, a take-off Is 350 mm wide and 1.2 mm thick (outermost layer: outer layer:
A multilayer sheet having an inner layer = 180 μm: 150 μm: 870 μm) was formed.

This sheet was heated at 190 ° C. by infrared heating.
And a plug-assisted vacuum / pneumatic single-cavity thermoformer with an outer diameter of 75 mm and a bottom diameter of 52 m
m, a height of 70 mm, and a cup-shaped container having a body wall portion average thickness of 0.4 mm. The thickness of the body wall is 60 μm: 50.
μm: 290 μm.

The molded container was filled with a white colored liquid content, sealed, and observed under irradiation of light. As a result, the periphery was white and the center was brilliant yellow. On the surface, a deep cat's eye effect was developed.

Example 6 The same as above, except that low-density polyethylene alone having MI = 1.3 and d = 0.92 was used as the outermost layer material, and 2% by weight of mica titanium pigment (light yellow) was used as the interference layer (outer layer) material. Polyethylene, the same polyethylene as the inner layer, diameter Φ4
0 (L / D = 25) outermost layer extruder, diameter Φ40 (L / D
D = 25) extruder for outer layer, diameter Φ75 (L / D = 32)
The outer diameter of 39 mm (outermost layer: outer layer: inner layer =)
(40 μm: 50 μm: 400 μm) was molded into a multilayer tube. The die head extrusion temperature was 180 ° C. and the take-off speed was 9.5 m / min.

A shoulder and a nozzle were applied to the tube by a tube shouldering machine. After filling the extruded tube with the liquid content colored white and sealing it,
Observation under light irradiation revealed a deep cat's-eye effect with a white surrounding and a brilliant yellow center.

Example 7 A co-injection machine capable of arbitrarily controlling the timing of main injection and sub-injection was used for the production of a multilayer preform. Polyethylene terephthalate (PET) having an intrinsic viscosity of 0.75 and containing 2% by weight of mica titanium pigment (light blue) was supplied to the sub-injector, and the same PET material as described above was supplied to the main injector.

First, the molten mica titanium pigment-containing PET is primarily injected into the cavity by the sub-injector, and then the uninjected PET material is injected into the cavity with a delay of one second and a slightly higher injection pressure than the primary injection. From the cavity.
Finally, the PET material containing the mica titanium pigment was secondarily injected again by the sub-injection machine at an injection pressure slightly lower than that of the primary injection to form a 4 mm-thick two-layer, three-layer multilayer preform.

The multilayer preform was heated to about 98 ° C., and biaxially stretched and blow-molded two times vertically and three times horizontally to form a bottle having an internal volume of 500 mL. The thickness of the trunk is 0.3m
m and the layer configuration was 75 μm: 150 μm: 75 μm.

The molded bottle was filled with a white colored liquid content, sealed, and observed under irradiation of a light beam. As a result, it was found that the periphery was white and the center was brilliant yellow.
The cat's eye effect with the gloss and depth peculiar to ET appeared.

Example 8 As the outermost layer, MI = 2 and ethylene content of 8 mol%
80% by weight of propylene-ethylene block copolymer
And a high-density polyethylene having a density of 0.96 g / cc are supplied to an extruder for the outermost layer. As an interference layer (outer layer), an ethylene content of 4% containing 2% by weight of mica titanium pigment (blue), A propylene-ethylene random copolymer having a weight average molecular weight of 30 × 10 ⁴ is supplied to an outer layer extruder, and as an inner layer, an ethylene-propylene block copolymer having an MI of 1.5 is supplied to an inner layer extruder. Three layers of molten parison were formed at a resin temperature of 190 ° C.

In order to give the shell a shell-like appearance and to prevent air trapping, the parison had an inner surface of a mold having a particle size of 500.
Blow molding was performed in a blow mold blasted with μm to 250 μm glass beads. The bottle after molding was filled with a white colored liquid content, sealed, and observed under irradiation of light. As a result, the periphery was white, the center was brilliant yellow, and the gloss was 6% or more. A good wax luster was obtained, like the inside of a shell with a nice appearance.

Example 9 (Reference Example) Example 1 was repeated except that the resin color of the inner layer was gray and the colors of the outer layer containing mica titanium pigment were blue, red and yellow, respectively.
A multilayer bottle was produced in the same manner as described above. The diffuse reflection spectral characteristics of this multilayer container were measured. Tsushima UV-310 for measurement
Using a 0PC spectrophotometer and a wavelength of 300 using an integrating sphere.
The range from nm to 1000 nm was measured. The spectral characteristics of the diffuse reflection light from the outer surface of each container were measured, and the spectral characteristics of the gray resin in the inner layer were obtained by measuring the diffuse reflection light from the inner surface of the container. The spectral characteristics of the outer layer containing the mica titanium pigment shown in FIG. 5 were obtained by numerically subtracting the spectral reflectance characteristics of the inner layer resin from the spectral characteristics of the outer surface diffuse reflection light of each container. 7 from 400 nm which is the visible light region
Between 00 nm, each pigment has a characteristic absorption peak due to interference of the mica titanium pigment, and a complementary color corresponding to these absorption wavelengths is visually recognized.

[0100]

According to the present invention, a multilayer resin container is formed by combining the above-mentioned mica-titanium pigment-containing interference layer and the transparent inner layer, and the container is filled with a colored liquid content to form a special package. A decorative effect, that is, a cat's eye effect is obtained. That is, when light is allowed to enter the hollow container, a chromatic light background due to the reflection or transmission of the colored liquid content and the reflection interference color of the interference layer appear at the center of the container at the same time, resulting in brilliancy. A brilliant and cats-eye-like decoration effect. For this reason, the container of the present invention is effective for increasing the commercial value of the container as a container for storing cosmetics, various chemicals, various foods, and the like.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a sectional structure of a multilayer packaging container of the present invention.

FIG. 2 is a sectional view showing another example of the sectional structure of the multilayer packaging container of the present invention.

FIG. 3 is an explanatory view showing a special decorative effect, that is, a cat's eye effect in the multilayer packaging container of the present invention.

FIG. 4 is an explanatory diagram for explaining generation of interference chromatic colors by a mica titanium pigment.

FIG. 5 is an explanatory diagram for explaining the occurrence of the cat's eye effect.

FIG. 6 is a graph showing wavelengths of 300 to 1000 nm using an integrating sphere for each container having an outer layer of a resin composition containing a mica titanium pigment exhibiting yellow, blue, and red interference colors, respectively.
5 is a graph showing the results of measuring the diffuse reflection spectral characteristics of the sample.

FIG. 7 is a sketch of a microphotograph showing a dispersion state of mica titanium pigment in an interference layer in Example 1.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container wall 2 Outer layer 3 Inner layer 4 Continuous phase of thermoplastic resin 5 Mica titanium pigment 6 Colored liquid content 10 Hollow container 11 Chromatic light line or band 12 Ambient reflection interference color 15 Mica substrate 16 Titanium dioxide fine particles Deposited layer

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-14429 (JP, A) JP-A-54-7485 (JP, A) JP-A-2-215529 (JP, A) JP-A-4- 65228 (JP, A) JP-A-7-89526 (JP, A) JP-B-53-41596 (JP, B2) JP-B-43-25644 (JP, B1) (58) Fields investigated (Int. Cl. ⁶ , DB name) B65D 1/00-1/48 B65D 25/00-25/34

Claims (10)

(57) [Claims] 1. A container comprising : a transparent thermoplastic resin inner layer; and a scaly thin film provided outside the inner layer and having a high refractive index.
Included oriented in the plane direction of the surface, emits a specific chromatic color selectively by interference of light, and an overall transparent or translucent multilayer resin container including an interference layer made of a synthetic resin having transparency, It consists of a colored liquid content filled in the container, and when light is incident on the surface of the container, the brightness is reflected on the surface reflection portion of the container.
Lines or bands of high surface reflection light and chromatic interference color light
The reflected light from the colored liquid is
A colored liquid package having a so-called "cat's eye" decorative two-color coloring effect in which the transmitted light appears, and the reflected or transmitted light from the colored liquid and the chromatic interference color from the interference layer are simultaneously viewed. . 2. A mica titanium pigment is used as a flaky thin film having a high refractive index, and its mixing ratio is 2 to 300 mg / dm ² in terms of unit area, particularly preferably 10 to 10 mg / dm ² .
Colored liquid package according to claim 1, 0 mg / dm ^2. 3. A flake of a micro-multi-laminate of a plurality of resin layers having different refractive indices is used as a flaky thin film having a high refractive index, and the mixing ratio is 0.1 to 25 in terms of unit area.
0 mg / dm ² , particularly preferably 1 to 70 mg / dm ^2
2. The colored liquid package according to claim 1, wherein 4. The colored liquid package according to claim 1, wherein the inner layer is formed of a highly transparent olefin resin or polyester resin. 5. A further one of claims 1 to 4 an ultraviolet absorber to minimize provided in close contact with the coating layer having a predetermined amount inclusive transparent outer layers yellowing on the outside of the multi-layer resinous container 3. The colored liquid package according to item 1. 6. A transparent thermoplastic resin inner layer having a high refractive index
Comprises There scaly thin film is oriented in the plane direction of the container surface, the synthetic resin having selectively exhibit specific color by interference of light, and an interference layer made of a synthetic resin having transparency, transparency outermost A transparent or translucent multilayer resin container as a whole comprising a laminate including an outer layer, and a colored liquid content filled in the resin container, and when light is incident on the container surface, the surface reflection portion of the container To brightness
Lines or bands of high surface reflection light and chromatic interference color light
The reflected light from the colored liquid is
A colored liquid package having a so-called "cat's eye" decorative two-color coloring effect in which the transmitted light appears, and the reflected or transmitted light from the colored liquid and the chromatic interference color from the interference layer are simultaneously viewed. . 7. The outermost layer has a weight average molecular weight (Mw) of 25.
× 10 in the range of ⁴ to 33 × 10 ⁴ and a propylene ethylene content of from 2 to 8 wt% - ethylene random copolymer colored liquid packaging of claim 6, wherein. 8. The colored liquid package according to claim 6, wherein the outermost layer is smoothed by a melting treatment of the molded container. 9. A blend wherein the outermost layer comprises a continuous phase (A) composed of a propylene-based resin and a dispersed phase (B) composed of an ethylene-based resin in a volume ratio of A: B = 90: 10 to 55:45. The colored liquid package according to claim 6, which is formed from: 10. The resin constituting the outer layer and the inner layer or the outermost layer is made of thermoplastic polyester.
6. The colored liquid package according to any one of 5 .