JPH08309835A - Multilayer blow bottle - Google Patents

Abstract

PURPOSE: To eliminate the contamination of the surface or the content due to bleed-out of inorganic ultraviolet absorbent or high heat in case of molding and to provide excellent durability of ultraviolet ray shielding effect by provid ing a resin layer mixed with a specific amount of the ultraviolet absorbent at the out layer of a multilayer blow bottle. CONSTITUTION: The mixing amount of inorganic ultraviolet absorbent is calculated from the thickness of a resin layer to be mixed and necessary ultraviolet ray shielding effect, and normally mixing of 1 to 5wt.% is preferable from the external appearance of a multilayer blow bottle having the ultraviolet ray shielding effect and the commodity value. The bottle 1 has an inner layer 1, an intermediate layer 3 and an outer layer 4. The bottle mixed with zinc oxide is obtained by mixing ultrafine particle zinc oxide having a particle size of 0.005 to 0.02μm of a hexagonal crystal with PET for biaxially oriented blow molding having an IV value of 0.75 and HDPE having a melt index of 0.4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blow bottle containing cosmetics, toiletry products, foods, and pharmaceuticals,
The present invention relates to a multi-layer blow bottle whose contents can be seen, is safe, and has an ultraviolet blocking property.

[0002]

2. Description of the Related Art It has been well known that cosmetics, toiletry products, foods, medicines, and the like filled in a container have their contents fading, degrading, or deteriorating due to ultraviolet rays. In particular, the plastic container is excellent in transparency in which the filled contents can be seen, but has almost no light blocking property. Therefore, the contents filled in the plastic container are
In the process of product distribution, it may deteriorate due to the effects of light rays, oxygen, especially ultraviolet rays, resulting in deterioration of product quality such as deterioration of taste, discoloration or fading, and deterioration of drug efficacy. It is important for packaging to prevent deterioration of quality such as discoloration, fading and deterioration of these contents. In order to protect such contents that are likely to deteriorate in quality, use a metal foil such as aluminum, metal vapor deposition, or a container made of resin mixed with an opaque pigment.
An opaque container that shields visible rays and ultraviolet rays and has an oxygen shielding effect has been conventionally used.

[0003]

However, although such a bottle can be shielded from ultraviolet rays, it also blocks the rays in the visible light region, so that the contents cannot be seen from the outside, and the contents cannot be confirmed. There are difficulties in the appearance quality of products. Therefore, when it is necessary to use a transparent container that allows the contents to be seen, an ultraviolet absorber is added to the resin. Organic compounds are generally known as the ultraviolet absorber. Although these organic ultraviolet absorbers have an ultraviolet shielding effect, the ultraviolet shielding effect may gradually decrease due to the alteration of the absorbent itself. In addition, there is a problem in stability and effect against discoloration, deterioration and deterioration of the filled contents.
Further, generally, the ultraviolet absorber is mixed in the resin, but there is a concern that it may bleed out on the surface of the resin or decompose or sublimate due to high heat during molding and volatilize and adhere to the resin or the discharge port of the resin of the molding machine. is there. It is desirable to prevent the blow bottle surface from being adversely affected by such elution of the ultraviolet absorbent and its adhesion to the molding die or molding machine.

On the other hand, a resin composition in which a resin is mixed with an inorganic ultraviolet absorber such as zinc oxide is also known. This inorganic ultraviolet absorber, particularly, the ultrafine inorganic ultraviolet absorber has excellent transparency and has an ultraviolet shielding effect and durability, but the resin composition containing this causes cloudiness and a thick resin layer. In the case of, there is a problem that the transparency and appearance are inferior. Therefore, in the case of a single-layer blow bottle having a thick resin layer, there is a large difference in the thickness of the mouth, shoulder, body, and bottom of the blow bottle. There is a large difference in the transparency and appearance of the thin-walled body, and the quality of the blow bottle's appearance deteriorates considerably. Furthermore, when an inorganic UV absorber is added to the resin, the surface of the resin becomes rough and the gloss is reduced, the appearance of the molded container is poor, and it cannot be put to practical use for multi-layer blow bottles such as cosmetics, toiletry products and foods. There are drawbacks. Further, since the inorganic UV absorber is more expensive than the organic UV absorber, there is a drawback that the blow bottle is expensive.

The present invention has been made by paying attention to the above-mentioned problems, and there is no bleed-out of the ultraviolet absorbent or contamination of the surface of the blow bottle or the contents due to high heat during molding, and the effect of shielding the ultraviolet rays. It is an object of the present invention to provide a blow bottle which is excellent in durability, allows the filled contents to be seen with the naked eye, is low in cost, and is excellent in safety.

[0006]

In order to solve the above-mentioned problems, the multilayer blow bottle of the present invention is composed of two or more layers which are transparent at the time of stretching, and at least one of them has an inorganic ultraviolet absorber. The main feature is that is blended. The multilayer blow bottle may be a generally known biaxially stretched or direct blow molding such as a multilayer blow bottle, a multilayer stretch blow bottle, a multilayer injection blow bottle, or an injection blow mold blow bottle or other containers.

<Inorganic UV Absorber> The inorganic UV absorber used in the present invention includes ultrafine particles of zinc oxide, titanium oxide, iron oxide, and cerium-containing zirconia particles, and particle diameters thereof for improving transparency. However, there are some types that have been treated with other inorganic substances in order to reduce the effect of the inorganic UV absorber on the resin and to improve the function.
Any generally known other inorganic ultraviolet absorber may be used as long as it does not hinder the present invention. As the zinc oxide, ultrafine zinc oxide having a hexagonal grain size of 0.005 μm to 0.05 μm is used. Titanium oxide has a particle size of 0.01-
Titanium oxide having a fine particle size of 0.05 μm is preferable because of its excellent transparency. Further, iron oxide having a particle diameter of 0.1 μm or less is slightly colored, but it is preferable because it has excellent transparency. In addition to these, any inorganic ultraviolet absorber may be used as long as it is a multilayer blow molding using at least one layer of a resin containing these inorganic ultraviolet absorbers and the filled contents can be seen from the outside. The blending amount of the inorganic ultraviolet absorber is
It is calculated from the thickness of the resin layer containing the UV absorber in the container and the necessary UV shielding effect. Normally, it is 0.1 from the UV shielding effect and the appearance of a multi-layer blow bottle with commercial value.
A blending amount of 5 wt% to 5 wt% is preferable. If the blending amount is 5 wt% or more, the appearance of the multilayer blow bottle is poor and it is not practical. When applied to a frosted glass, ceramics, or pearl luster translucent multi-layer blow bottle, the cloudiness due to the blending of the inorganic UV absorber is difficult to understand from the appearance of the multi-layer blow bottle, so the blending of 10 wt% There is practicality. In addition, even if a single-layer blow bottle contains a large amount of an inorganic ultraviolet absorber and is difficult to mold, the multi-layer blow molding improves the moldability.
10 wt% can be blended. When the content of the inorganic ultraviolet absorber is 0.1 or less, the ultraviolet ray shielding effect is poor and it is not practical. On the other hand, if it is 10 wt% or more, the appearance of the multi-layer blow bottle is inferior and the moldability is deteriorated. Since a resin containing an inorganic UV absorber is used in at least one layer of a multi-layer blow bottle, the amount of UV absorber used is smaller than in the case of using an inorganic UV absorber-containing resin as a whole as in a single-layer blow bottle. Complete. In addition, since the thickness of the resin layer containing the UV absorber can be controlled to be thin, the cost will be low,
The transparency is also improved.

<Constituent Resin of Multilayer Blow Bottle> The resin used in the present invention is polyethylene terephthalate (hereinafter referred to as P
Abbreviated as ET), polypropylene (hereinafter abbreviated as PP), low density polyethylene (LDPE), high density polyethylene (hereinafter abbreviated as HDPE), polymethylpentene, copolymers of these polyolefins, cyclic polymers, metallocenes. It is preferable to use transparent resin such as polyolefin resin such as polymerized by using catalyst, polystyrene, polystyrene resin such as AS resin and ABS resin, polycarbonate, ionomer resin, etc. When molded, it may be a resin that transmits visible light and ultraviolet rays. It should be noted that the resin composition of the multi-layer blow bottle is such that the same type or different types of resins among the above resins are combined and a multi-layer resin including an adhesive resin layer for adhering different types of resin is used and the productivity is improved. Designed to suit. Also, multi-layer blow bottles may have containers other than blow bottles.

<Transparent Resin on Resin Surface> Since the inorganic ultraviolet absorber is mixed with the resin, the surface is easily roughened due to the influence of the granular resin. In such a case, transparent resin is used for the surface layer in order to improve the gloss of the surface of the multilayer blow bottle. The transparent resin is a transparent polyolefin resin such as PP, low density polyethylene, medium density polyethylene, HDPE, pomethylpentene, a copolymer of these polyolefins, a cyclic polymer, or a polymer having physical properties improved by a catalyst. , Ionomer resin, polyvinyl alcohol (EVOH), PET, polycarbonate, etc., as long as they are transparent and glossy resins and satisfy the scope of the present invention.

<Compounding agent for resin> Various additives such as an antioxidant, a coloring agent, a slip agent, an antistatic agent and an inorganic filler may be blended with the resin within the range that does not impair the present invention.

<Frosted glass-like, ceramic-like, pearly luster-like outer surface layer> The frosted glass-like outer surface of a multilayer blow bottle has a roughened mold surface, and the grain size of crystalline resin crystals is controlled. And an inorganic filler that forms a ground glass with a coloring agent, or an organic filler that melts at the molding temperature. The multilayer blow bottle with frosted glass appearance has at least one resin layer containing 0.1 wt% to 10 wt% of inorganic ultraviolet absorber, the outer surface layer is frosted glass, and the visible light of wavelength around 550 nm Any multi-layer blow bottle having a transmittance of 5% or more may be used. The ceramic-shaped multi-layer blow bottle is a multi-layer blow bottle that uses at least one layer of ceramic-colored resin. The pearly luster multi-layer blow bottle is a multi-layer blow bottle that uses at least one layer of a resin colored in pearly luster. These multi-layer blow bottles, which have a ceramic or pearly luster appearance, contain 0.1% by weight of an inorganic ultraviolet absorber.
At least one resin layer containing 10 wt% may be used, and any resin may be used as long as the transmittance of visible light at a wavelength of about 550 nm at which the filled contents are visible is 5% or more. It should be noted that even in a multi-layer blow bottle having an inorganic ultraviolet absorber blended in an amount of 0.1 wt% to 10 wt% and having a color tone appearance that makes cloudiness inconspicuous, and having a visible light transmittance of 5% or more in a wavelength region around 550 nm. good.

The multi-layer blow bottle of the present invention is not only a non-colored multi-layer blow bottle but also a colored multi-layer blow bottle which is transparent or semi-transparent so that the contents filled in the multi-layer blow bottle by natural light or artificial light such as electric light can be seen. Any of them can be used.

<Transmittance> According to JIS K 6714, the transmittance of visible light in the present invention means a width of 13 mm and a length of 4 mm from the center of the multilayer blow bottle of the sample.
Cut to 0 nm and measure. The thickness is the thickness of the original plate. A piece of the sample is placed in a holder, light of each wavelength is transmitted, and the transmittance of visible light at 550 nm is read by a magnetic spectrophotometer.

[0014]

[Working] Organic UV absorbers are
In some cases, it cannot be used by being mixed with a container that comes into direct contact with the contents to be filled such as cosmetics, toiletry products, pharmaceuticals, and food. Inorganic ultraviolet absorbers such as zinc oxide are used as external powders and ointments. As is well known, titanium oxide is also safe and is widely used in cosmetics, cosmetics containers, food containers and the like. Inorganic UV absorbers are safe as described above, and are safe because a resin containing them is used and do not contaminate a mold, an apparatus, or a multi-layer blow bottle during molding.

<Storability, transparency and cost> Generally known organic UV absorbers such as benzophenone type, paraaminobenzoic acid type, methoxycinnamic acid type and salicylic acid type have a problem in durability, and they cannot be used for a long time. If you do, the function will be inferior. This tendency is particularly strong when used for thin resin layers.
In addition, since the organic UV absorber has a very low solubility in resin, it easily bleeds out, the compounding amount cannot be increased, and a thick resin layer is required to block UV rays. However, since the resin layer containing the inorganic ultraviolet absorber does not have such a phenomenon, it can be made thin. In addition, organic UV absorbers are thermally unstable and can be decomposed or deteriorated at high temperatures during resin coloring or molding and processing, and also sublimate, adhere to molds and molding machines, and be molded. The multilayer blow bottles may be contaminated with organic UV absorbers, and the contents filled in the multilayer blow bottles may be contaminated with UV absorbers, but inorganic UV absorbers are durable. Furthermore, a resin layer containing a UV absorber mixed in one layer of a multi-layer blow bottle can be thinly formed to a required thickness that has an UV shielding effect. The transparency can be improved by the amount that can be used for this thin layer, and the amount of the ultraviolet absorber used is also reduced, resulting in cost reduction.
If necessary, an oxygen barrier resin can be used in one layer of the multi-layer blow bottle to provide oxygen barrier properties. Therefore, it is possible to prevent deterioration of quality such as deterioration of taste and discoloration of the contents filled in the container due to ultraviolet rays and oxygen, and to improve storability. Further, since it is transparent or translucent, the filled contents can be confirmed from the outside, so that the product can be effectively advertised and the reliability of the product can be increased. In addition, it is convenient because the usage of the contents can be checked at the time of use.

<Improvement of appearance> In the case of a single-layer blow bottle,
When an inorganic UV absorber is blended with the resin, the thickness of the resin in a single layer is thick, so the blow bottle becomes cloudy and the transparency becomes unbalanced, which impairs the appearance and results in cosmetics, toiletry products, food and pharmaceutical products, etc. Is not practical.
However, in the case of a multi-layer blow bottle, since the ultraviolet absorber is mixed in at least one of the multi-layer resin layers, the thickness of the resin layer containing the ultraviolet absorber becomes thin. Also, if necessary, the thickness can be controlled to the required thickness. Moreover, since the inorganic ultraviolet absorber has excellent durability and ultraviolet shielding effect, unlike the organic ultraviolet absorber, the resin layer containing the ultraviolet absorber can be thin. As a result, the amount of ultraviolet absorber used per resin container is small, so the cost is low, transparency is improved, and appearance is improved.

<Improvement of gloss> When an inorganic ultraviolet absorber is added to a resin, the surface of the resin becomes rough and loses the gloss, so that the surface of the container was not glossy, but excellent gloss such as for cosmetics and toiletries is required. In the case of the container, by using the inorganic UV absorber-containing resin in the intermediate layer and the inner layer and using the glossy resin layer in the outermost layer, an excellent glossy and glossy appearance can be obtained.

<Maintaining the strength of the container> When the inorganic ultraviolet absorber is mixed with the resin, particularly when the ultraviolet absorber of ultrafine titanium oxide is mixed with the resin, the resin is deteriorated depending on the kind of the resin. There is something to do. Therefore, when a blow bottle is formed by using a resin containing a UV absorber as a single layer, the strength of the container may deteriorate over time. In the case of a multi-layer blow bottle, a resin containing an inorganic UV absorber is used for one layer of the resin layer, and a resin or adhesive layer that does not deteriorate over time can be selected and used for the other layers. In addition, even if a resin that tends to deteriorate can be used for one layer of a multi-layer bottle, even if some resin layers deteriorate, other layers that do not contain an inorganic ultraviolet absorber will be used. The strength of the container makes it possible to maintain the strength of the container.

[0019]

EXAMPLES The multi-layer blow bottles of the examples of the present invention will be described in more detail below. The multilayer blow bottle of this embodiment is an example of the multilayer blow bottle of the present invention and is not limited to this embodiment. <Comparison between multi-layer blow bottle containing zinc oxide and single-layer blow bottle> FIG. 1 shows a cross-sectional shape of this multi-layer blow bottle. This blow bottle 1 has an inner layer 2, an intermediate layer 3 and an outer layer 4. The multilayer blow bottle containing zinc oxide is composed of hexagonal ultrafine zinc oxide having a particle size of 0.005 μm to 0.02 μm, PET for biaxial stretching blow molding with an IV value of 0.75, and a melt index ( Hereinafter, each is abbreviated as MI) to 0.4 HDPE. The resin containing these ultraviolet absorbers is the intermediate layer 3 in FIG.
Used for. PET is biaxial stretch blow molding, HDP
For E, direct blow molding was performed (Examples 1 to 8).
In addition, as a comparative example, “PET containing no UV absorber was used.
Bottle (Comparative Example 1) and HDPE bottle (Comparative Example 6) ", an organic ultraviolet absorber (Tinuvin; manufactured by Ciba-Geigy Co., Ltd.) having a normal use amount of 0.1 wt% is used as a middle layer of a resin having a three-layer structure. A bottle "PET bottle (Comparative example 2), HDPE bottle (Comparative example 7)" was prototyped. Further, a single-layer blow bottle was molded from a resin mixed with ultrafine zinc oxide having a hexagonal grain size of 0.005 μm to 0.02 μm (Comparative Examples 3, 4, 5, 8, 9). The following table is a list of molded bottles.

[Table 1]

<Comparison of Appearance of Prototype Bottles> Comparative Examples 3, 4
In the case of a single-layer blow bottle using a resin containing ultrafine zinc oxide, as in Nos. 5, 8 and 9, the bottle mouth (thickness;
(3.3 mm) and the body (thickness: 1.3 mm) have a large difference in wall thickness partially, resulting in a considerable difference in transparency, resulting in an inferior external appearance of the bottle, making it a practical product bottle. Absent. However, as in Examples 1 to 8, in the multilayer blow bottle in which ultrafine zinc oxide is mixed in the intermediate layer, the resin layer containing the ultraviolet absorber is thin (thickness: 0.13 m).
Therefore, the transparency is improved, there is no difference in the appearance of each bottle portion, and the appearance is improved and it can be put to practical use.

<Appearance of PET Prototype Bottle> A single-layer biaxially stretch blow-molded polyethylene terephthalate bottle (so-called PET bottle) containing ultrafine zinc oxide (Comparative Examples 3 to 5) has a thick bottle mouth portion. Since there is a considerable difference in transparency between the shoulders and the thin body,
It is not practical for containers for cosmetics, toiletries, foods, medicines, etc. The three-layer biaxially stretch blow-molded PET bottles (Examples 1 to 3) using the same amount of the ultraviolet absorbent-containing resin in the intermediate layer (thickness 0.13 mm) were used to absorb the inorganic ultraviolet light of ultrafine zinc oxide. Since the intermediate layer containing the agent is thin, there is almost no difference in transparency between bottle parts, and the appearance is good, and it can be put to practical use.

<Appearance of HDPE Bottle> A high-density polyethylene bottle (HDPE bottle) (comparative example 6), which is a single-layer blow bottle containing no inorganic ultraviolet absorber, has a peculiar appearance of HDPE and is slightly translucent. However, when 0.3 wt% (Comparative Example 8) and 0.6 wt% of ultrafine zinc oxide were blended (Comparative Example 9), a thick bottle mouth (thickness: 3.3 mm) and shoulders And thin body (thickness: 1.
(3 mm) has a considerable difference in transparency, is unbalanced and has a poor appearance, and is not practical. However, a three-layer HDPE direct blow bottle using a resin containing 0.3 wt% (Example 7) and 0.6 wt% (Example 8) of ultrafine zinc oxide as an intermediate layer contains an absorbent. Since the resin layer is thin (thickness: 0.13 mm), there is little difference in the partial thickness of the bottle and the appearance is good, so it can be put to practical use in cosmetics, toiletry products, foods, pharmaceutical containers. Also, the filled contents are visible.

<Confirmation Test of UV Shielding Effect> The following experiment was conducted to confirm the UV shielding effect of a multi-layer blow bottle containing an inorganic UV absorber. That is, the bottles of Examples 1 to 8 of PET and HDPE of three layers using a resin containing ultrafine zinc oxide as an intermediate layer, and a stretch blow PET bottle containing no ultraviolet absorber (Comparative Example 1) and HDPE.
A direct blow bottle (Comparative Example 6) was filled with a solution obtained by coloring a mixed solution of 85 wt% ion-exchanged water and 15% ethyl alcohol with brilliant blue. Next, these bottles were placed in a light resistance tester and irradiated with a carbon arc lamp for 20 hours. The results are shown in Table 2.

[Table 2]

<Results> The degree of discoloration of the content liquid after irradiation was visually measured. Discoloration was remarkable in the liquid contents of the bottles of Comparative Examples 1 and 6 in which the ultraviolet absorber was not added, without needing to measure the color difference of the contents. The content liquids of the bottles of Examples 2 to 8 containing the zinc oxide had a greater discoloration as the content of the zinc oxide was smaller, but the discoloration was significantly less than that of the bottles containing no zinc oxide and was practically acceptable. At the same time, the content liquid of the bottle of Example 1 containing 0.05 wt% of ultrafine zinc oxide was significantly discolored, which was not acceptable in practice.

<Comparison of Organic and Inorganic UV Absorbers> In order to compare the durability of organic and inorganic UV absorbers, P
A resin layer containing 0.1 wt% of an organic ultraviolet absorber TINUVIN (manufactured by Ciba Geigy) having a body thickness of 0.13 mm was used as an intermediate layer of a three-layer blow bottle of ET and HDPE. Layer bottles (Comparative Examples 2 and 7) and ultrafine zinc oxide in the intermediate layer PET of 0.1, 0.3, 1.
Two layers of biaxially stretched blow molded PET bottles (Examples 2, 3, 4, 5, 6) blended with 2, 2.5, wt% and 0.3 wt% of ultrafine zinc oxide, and 0. A 6% by weight mixed MI 0.4 HDPE direct blow bottle (Examples 7 and 8) was filled with the same content liquid as in the above-mentioned test for confirming the ultraviolet shielding effect, and each was placed in a light resistance tester. The carbon arc lamp was irradiated for a long time (40 hours irradiation) in order to compare the durability of the absorbent.

<Results> As shown in Table 2, a bottle containing the organic UV absorber tinuvin (Comparative Example 2,
Fading of the content liquid of 7) was remarkable, and almost colorless. The contents of the bottles containing the inorganic ultraviolet absorber (Examples 2 to 8) were slightly discolored, slightly discolored, or did not discolor, and were in the acceptable range. That is, it was confirmed that the durability of the inorganic ultraviolet absorber was remarkably excellent when a blow bottle in which an organic ultraviolet absorber and an inorganic ultraviolet absorber were mixed in a multilayer blow bottle was compared.

<Semi-transparent ground glass or ceramic bottle> A multi-layer blow bottle using a resin layer in which an inorganic ultraviolet absorber is mixed with a semi-transparent ground glass or ceramic multi-layer blow bottle is examined. Therefore, a multilayer blow bottle was prototyped as shown in Tables 3 and 4.

[Table 3]

<Prototype of Frosted Glass Bottle (Example 9)
~ 13)> In order to form a ground glass multi-layer blow bottle, the surface of the mold with the same dimensions as in Fig. 1 is roughened so that the bottle is blow-molded into a frosted glass. A multilayer blow bottle was prototyped. For comparison, a PP bottle containing no UV absorber (Comparative Example 10) was manufactured as shown in Table 3.

<Prototype of Ceramic Bottle (Examples 14 to 1)
9)> In order to study a bottle using a resin in which an inorganic ultraviolet absorber is blended in the middle layer of a three-layer blow bottle using PET colored in a ceramic shape as the outer layer, Example 1
Similar to 8, the three-layer blow bottle mold shown in FIG. 1 was used to prototype a bottle as follows.

[Table 4] Inorganic UV absorbers were blended in the intermediate layer and the inner layer as shown in Table 4. For comparison, a ceramic-like bottle containing no ultraviolet absorber (Comparative Example 11) was manufactured as shown in Table 4.

<Prototype Results / Bottle Appearance> Table 5 shows Example 9
13 to 13 and Comparative Example 10, Examples 14 to 1 in Table 6 are shown.
9. As described in Comparative Example 11, a bottle having a good appearance was obtained. In particular, the ground glass bottle of Example 13, and
In Example 19 of the ceramic-like bottle, although the blending amount of ultrafine zinc oxide was as large as 10 wt%, it was possible to perform molding because of multilayer blow molding, and clouding of the resin due to the blending of the ultraviolet absorber was not noticeable. As compared with the bottles of Comparative Examples 10 and 11 in which no ultraviolet absorber was blended, there was almost no difference in appearance, and the bottles were good and practical.

[Table 5]

[Table 6]

<Results of light resistance test> In order to confirm the ultraviolet shielding effect of the prototype bottle, a mixed solution of 85 wt% ion-exchanged water and 15 wt% ethyl alcohol was colored with brilliant blue and filled in the bottle. The bottle was set in a light resistance tester and irradiated with a carbon arc lamp for 20 hours. The results show that, as shown in Tables 5 and 6, in the bottles of Comparative Examples 10 and 11 using the resin containing no ultraviolet absorber, the content liquid almost faded, but an inorganic ultraviolet absorber was added. The liquid contents of the three-layer blow bottles (Examples 9 to 19) were in the acceptable range with almost no discoloration.

<Measurement of Visible Light> Tables 5 and 6 show the results obtained by irradiating the bottles of Examples 9 to 19 with visible light having a wavelength of 550 nm. The container containing ultrafine titanium oxide and ultrafine zinc oxide has a wavelength of 550 nm.
If the bottle has 5% or more visible light, the contents can be seen from outside the container and the usage amount can be confirmed.

[0033]

INDUSTRIAL APPLICABILITY The multi-layer blow bottle of the present invention has a UV shielding effect even though the filled contents can be seen from the outside of the bottle. It is possible to prevent it and to improve the storability. Also, since the contents can be seen, it is convenient to check the usage amount of the contents when using. In addition, when at least one layer of the multi-layer blow bottle is made of a blended resin of an inorganic UV absorber, it is possible to select a thin thickness considering the UV blocking effect and appearance, so the amount of expensive inorganic UV absorber used The amount is small, and the cost is reduced by this amount. Also, since it can be used in a thin layer, the transparency and appearance of the bottle are significantly improved compared to a single layer bottle. Inorganic UV absorbers are safe. In addition, when a large amount of inorganic UV absorber is added, the moldability is poor,
Although it may not be possible to mold with a single-layer bottle, in the case of a multilayer blow bottle, a resin with poor moldability containing a large amount of an inorganic UV absorber can be used for the thin layer of the multilayer blow bottle, so it has good moldability. The resin effect of the layer allows easy molding. When an inorganic UV absorber is blended, the surface of the resin becomes rough due to the effect of the inorganic UV absorber that does not melt into the resin, and the surface of the molded bottle is damaged. However, use a transparent resin for the surface layer of the multilayer blow bottle. As a result, a blow bottle with a glossy and excellent appearance can be obtained. Further, even if the strength of the resin is lowered, the required strength can be maintained by using a resin having a high strength for the other layers. Even if the transparency of the resin decreases depending on the amount and type of inorganic UV absorber compounded in the resin, at least one layer of frosted glass, porcelain, or pearl-shaped, relatively low transparency absorbs inorganic UV By using the agent, it is possible to obtain a multi-layer blow bottle having a superior ultraviolet absorbing effect without impairing the appearance of the bottle.

[Brief description of drawings]

FIG. 1 is a diagram of a multilayer blow bottle according to an embodiment of the present invention.

[Explanation of symbols]

1 ... Blow bottle 2 ... Inner layer 3 ... Middle layer 4 ...
Outer layer

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Claims (4)

[Claims] 1. A multi-layer blow bottle comprising two or more layers, wherein at least one layer contains 0.1 wt% of an inorganic ultraviolet absorber.
% Blow bottle with a resin layer containing 5% by weight. 2. The inorganic ultraviolet absorber is ultrafine zinc oxide having a hexagonal grain size of 0.005 μm to 0.05 μm,
2. The multilayer blow bottle according to claim 1, which is an ultrafine particle titanium oxide having a particle diameter of 0.01 to 0.05 μm, or an iron oxide having a particle diameter of 0.1 μm or less, or any one of them alone or a mixture thereof. 3. An outer layer having a transparent resin layer.
The described multilayer blow bottle. 4. An inorganic ultraviolet absorber in an amount of 0.1 wt% to 10
It has at least one layer containing wt% and has a wavelength of 550n.
Visible light transmittance of 5% or more in the m region, frosted glass,
Alternatively, a multi-layer blow bottle with either ceramic-like or pearly luster.