JP2001328613A - Packaging container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging container, particularly a glass bottle having a membrane to be formed of superior resistance to scratches and lubricity and also of superior label sticking properties, wettability, antifouling properties and resistance to water. SOLUTION: The packaging container is characterized by having a cover of protruded membrane composed of a polymer having a hydrophilic group on the outer face of the container.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging container having a hydrophilic film, and more particularly, to a film formed with excellent scratch resistance and lubricity and excellent label sticking. The present invention relates to a packaging container having water resistance, water wettability and stain resistance, particularly a glass bottle.

[0002]

2. Description of the Related Art Glass bottles are excellent in transparency, rigidity and sanitary properties, have no problem of environmental pollution, and have been a container that can recover and reuse resources for a long time. It also has the disadvantage that it is easily broken. Nevertheless, there is a strong demand for reducing the weight of glass bottles from the viewpoint of reducing distribution costs.

[0003] Even though a glass bottle has a fairly strong strength in the initial stage of molding without any scratches on the surface, it is known that scratches or scratches on the surface significantly reduce the strength of the glass bottle. The generation of a flaw on the surface is a serious problem, especially in a lightweight glass bottle.

Heretofore, it has been known to perform a coating process called a hot end coat or a cold end coat on the surface of a glass bottle in order to improve the abrasion resistance of the glass bottle. For example, Japanese Patent Publication No. 42-1758 discloses titanium, zirconium, tin or vanadium which can form a metal oxide on a glass surface by thermal decomposition.
Treating the glass surface with the containing compound while the glass surface is at or above the thermal decomposition temperature of the compound, and cooling the treated surface to a temperature of 232 ° C. or less. Forming an olefin polymer, polyurethane, polystyrene or N-alkylamine acetate on the glass surface which is still heated to form a thin, firmly adhered, transparent, substantially colorless coating on the surface. A method for increasing the abrasion resistance of a glass surface, characterized in that the method is applied in a sufficient amount to the glass.

[0005]

The above-mentioned container formed with a coating of an olefin polymer such as polyethylene is inferior in the label sticking property as compared with the glass bottle itself.
Since it has poor water wettability, it has a drawback that the inspection device is likely to malfunction due to adhesion of water droplets in the filling step. Also,
The polyethylene-coated glass bottle has a drawback that dirt is easily adhered thereto, and is still not sufficiently satisfactory in terms of lubricity.

Accordingly, it is an object of the present invention to provide a packaging container which is excellent in abrasion resistance and lubricity and has excellent label sticking properties, water wettability, stain resistance and water resistance. , Especially in providing glass bottles. Another object of the present invention is to provide a cold end coat (CE
The object of the present invention is to provide a coated glass bottle which can be easily applied by C) and has a coating formed having the above-mentioned properties.

[0007]

According to the present invention, a coating is provided on the outer surface of a container, in which solid lubricant particles are projected from a film mainly composed of a polymer having a hydrophilic group. A packaging container is provided. In the packaging container of the present invention: Solubility parameter value of polymer having hydrophilic group (S
(p value) is 25 or more; 2. The polymer having a hydrophilic group is cellulose or a cellulose derivative; 3. The solid lubricant is an olefin resin or a high melting point wax; 4. the solid lubricant is a polyethylene wax or a modified polyethylene wax; 5. the container is a glass bottle; 6. the thickness of the film is in the range of 0.03 to 5.0 μm; 7. The ratio of lubricant particle diameter / film thickness is in the range of 1.1 to 3.5; 8. Solid lubricant particles are present in an amount of 3 to 70% by weight per hydrophilic group-containing polymer; It is preferable that the proportion of the lubricating particles protruding from the head to the surface is 1 to 60%.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [Action] In the packaging container of the present invention: B. A film mainly composed of a polymer having a hydrophilic group is formed on the outer surface of the container; It is characterized by solid lubricant particles protruding from the surface of this film, whereby the formed film is excellent in abrasion resistance and lubricity, as well as label sticking property, water wettability. In addition, the advantage of the function and effect of being excellent in stain resistance is achieved.

In the present invention, it is basically important to provide a film mainly composed of a polymer having a hydrophilic group on the outer surface of a container such as a glass bottle. By providing a film mainly composed of the above polymer on the outer surface, hydrophilicity is imparted to the outer surface of the film, water wettability is imparted to the outer surface of the container, and an inspection machine for liquid level detection in the filling step. Can prevent the adhesion of water droplets, which can cause malfunction, can improve the label sticking property, and can improve the stain resistance.

In a normal glass container, the contents, source, expiration date and the like are indicated by sticking a label.
Traditionally, starch paste has been widely used for sticking this label. This seems to be closely related to the fact that the glass surface is essentially hydrophilic when it is not soiled, and that the label is peeled off by immersion in water when the glass bottle is reused. Since the outer surface of the coated container in the present invention is essentially hydrophilic, the advantage of excellent sticking property of the label is achieved.

In the step of filling the glass bottle, there are many occasions where dirt adheres to the glass bottle.
First, in the glass bottle washing process, there is an opportunity to attach dirt substances derived from the coating material, in the filling process, there is an opportunity to attach the content blown out due to generation of bubbles as dirt, and further, in the heat sterilization process, the outer surface of the container. In some cases, the contents adhered to the container may be dissolved or dispersed in hot water or the like and adhere to the outer surface of the container again. Among these adhering dirts, troublesome dirts are oily, and even if they come into contact with water or hot water, they are not removed from the glass surface but remain as they are. In the present invention, since the outer surface of the coated glass is made hydrophilic, the oily dirt is less likely to adhere, and even if it adheres, it easily separates from the outer surface. Benefits are achieved.

A second feature of the present invention is that the coating structure is such that solid lubricant particles emerge from the surface of the coating mainly composed of the above-mentioned polymer having a hydrophilic group. Generally, for the purpose of imparting lubricity to a coating, it is common to mix a lubricant into the coating, but the improvement in lubricity and the improvement in scratch resistance due to the mixing of such a general lubricant are slight. And especially when the coating film is hydrophilic,
As shown in the examples below, the improvement is insignificant. On the other hand, according to the present invention, when the solid lubricant particles have a dispersed structure in which the head protrudes from the film surface, as shown in the examples described below, it is possible to impart excellent lubricity to the film surface and to obtain abrasion resistance. It is also possible to significantly improve the performance. It should be noted that the scratch resistance is obviously related to the lubricity of the film, but at the same time is also related to the film strength, and the coating of the dispersion structure of the present invention also increases the film strength.

The coating structure is formed by dispersing solid lubricant particles in a solution or dispersion of a polymer having a hydrophilic group, applying the resulting dispersion to the surface of a container such as a glass bottle, and drying. However, at this time, it is important that the solid lubricant particles remain in the coating while maintaining the particle structure. In this way, a part of the solid lubricant particles has a coating structure protruding from the smooth surface of the film.

In FIG. 1 for explaining the coating structure of the present invention, a hydrophilic film 2 is formed on the surface of a substrate 1 such as glass, and solid lubricant particles 3 are blended in the hydrophilic film. The solid lubricant particles 3 protrude from the film surface 4 and are exposed to the outside, and the lubricity of the exposed solid lubricant particles 3 eliminates scratching when the film is rubbed. That is, the solid lubricant particles 3 act to prevent direct contact between another object and the film surface 4 and reduce friction with the object due to its own lubricity.

In fact, when the film surface according to the present invention is observed with an electron microscope, it is confirmed that solid lubricant particles are distributed in the form of islands in the sea of the hydrophilic film as shown in the electron micrograph of FIG. .

[Hydrophilic film] In the present invention, the hydrophilic film formed on the surface of the substrate of the container is mainly composed of a polymer having a hydrophilic group. The polymer having a hydrophilic group preferably has a solubility parameter value of 25 or more. Solubility Parameter S
The p-value) is defined as a half-power value of the cohesive energy density (MPa), and is closely related to the strength of hydrogen bonding. If the Sp value of the polymer used is 25 or more,
A hydrophilic film can be formed on a container such as a glass bottle.

Examples of the hydrophilic group include a hydroxyl group, a carboxyl group in free or salt form, an amide group, and the like. Those having these hydrophilic groups in the main chain or side chain of the polymer are used. These hydrophilic polymers may be water-dispersible or water-soluble. Examples of the water-dispersible organic polymer include cellulose. As the water-soluble organic polymer, an anionic or nonionic water-soluble organic polymer is used. Examples of the anionic polymer include sodium polyacrylate or a copolymer of sodium polyacrylate and polyacrylamide, sodium polymethacrylate, sodium alginate, ammonium alginate, carboxymethyl starch, carboxymethyl cellulose, acrylamide-acrylic acid Copolymers, chitosan, sodium styrenesulfonate copolymer and the like are used. Examples of the nonionic polymer include polyvinyl alcohol (PVA), starch, cyanated starch, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, veegum, gelatin and the like. These hydrophilic polymers can be used alone or in combination of two or more.

In the present invention, it is preferable that the polymer having a hydrophilic group is cellulose or a cellulose derivative in view of water wettability, label sticking property, and film strength. It is particularly preferred that the hydrophilic film of the present invention is formed from a composition of cellulose and a water-soluble polymer, particularly a water-soluble cellulose derivative. Cellulose is hydrophilic but water-insoluble, and when used in combination with a water-soluble polymer, provides the water dispersibility required for preparing a coating solution and the coating property required for forming a film. The advantage is achieved that the resulting coating has a certain degree of water resistance while being hydrophilic. Generally speaking, the cellulose (A) and the water-soluble polymer (B) may be used in a weight ratio of A: B = 98: 2 to 50:50, particularly 95: 5 to 75:25. It is desirable to achieve the advantages.

[Solid Lubricant Particles] As the solid lubricant particles to be incorporated into the hydrophilic film, an organic solid lubricant is desirable, and a resin or wax having lubricity is used alone or in combination of two or more. The organic solid lubricant used preferably has a heat resistance of 80 ° C. or higher, and is preferably used to maintain the above-mentioned film structure in the formed film. From this viewpoint, resin-based solid lubricants and olefins having lubricity are preferred. A lubricant mainly composed of a resin, a fluorine resin or the like is advantageously used.

Particularly preferred resin-based lubricant particles are olefin-based resin particles, for example, low-, medium- or high-density polyethylene, 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-acrylic acid Particles such as an ester copolymer are used.

These olefin resins have a glass transition point lower than room temperature, and are particularly excellent in scratch resistance. The molecular weight of the olefin-based resin is not particularly limited, but a relatively low-molecular-weight resin generally called polyethylene wax gives an excellent effect. Modified olefin resins such as oxidized polyethylene wax and acid-modified polyethylene wax are also suitably used for the purpose of the present invention.

Another preferred example of the modified olefin resin-based lubricant particles is acrylic oxygen-modified resin particles having a glass transition point lower than room temperature. Examples of the acrylic monomer constituting the acrylic resin include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and (meth) acrylic acid. Isobutyl acid,
N-Amyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, (meth)
2-ethylhexyl acrylate, (meth) acrylic acid n
-Octyl and the like. However, the above (meth) acrylic acid refers to acrylic acid or methacrylic acid, and is a copolymer of 20 mol% or less. If necessary, these acrylic monomers may be copolymerized with other comonomers, for example, styrene, acrylic acid, methacrylic acid, maleic anhydride, divinylbenzene, ethylene glycol dimethacrylate, and the like.

Other examples of the resin fine particles include fluorine resins such as polytetrafluoroethylene, tetrafluoroethylene / hexafluoropropylene copolymer, polyvinyl fluoride, and polyvinylidene fluoride. Although these fluorine-based resins have a glass transition point higher than room temperature, their excellent slip properties contribute to scratch resistance.

Examples of solid lubricants other than resin-based lubricants include perm acetyl wax, montan wax, carnauba wax,
Waxes such as beeswax, wood wax, cotton wax and stearic acid amide, erucic acid amide, bis-amide stearate,
High melting point waxes such as higher fatty acid ethylenediamine derivatives can also be used alone or in combination with a resinous lubricant.

These solid lubricant particles preferably have an average particle size (volume-based median size) of generally 0.1 to 6.0 μm, particularly 0.2 to 2.0 μm. The particle shape of the solid lubricant particles is preferably spherical, but is not necessarily limited to this. Irregular particles formed by a pulverizing method or the like, or other regular particles may be used.

[Coating Composition] The coating composition used for coating containers such as glass bottles comprises, as essential components, a polymer (I) having a hydrophilic group and solid lubricant particles (II). The solid lubricant particles (II) are preferably used in an amount of 3 to 70% by weight, particularly 5 to 40% by weight, based on the hydrophilic polymer (I). If the amount of the solid lubricant particles is below the above range, the lubricity is insufficient, and the scratch resistance tends to decrease,
On the other hand, if the amount of the solid lubricant particles exceeds the above range, the film strength is reduced, and the abrasion resistance also tends to decrease.However, when the amount of the solid lubricant particles is within the above range, any of the above cases Can improve the abrasion resistance.

The above coating composition is generally preferably used in the form of an aqueous dispersion. This aqueous dispersion can be prepared by dispersing solid lubricant particles in an aqueous solution or aqueous dispersion of a hydrophilic polymer. The concentration of the hydrophilic polymer in the aqueous dispersion is not particularly limited, but is generally 0.1 to 50 g / L, particularly 0.5 to 10 g / g, expressed as g (gram) per 1 L (liter) of the liquid. L
Is preferable in terms of coating workability and controllability of thickness.

In the aqueous dispersion used in the present invention, the dispersibility of each of the above components is improved, or the dispersion stability is improved.
Further, a component for improving wettability to a container such as a glass bottle can be contained. Such components include surfactants and water-miscible organic solvents.

As the surfactant, for example, primary higher alcohol sulfate, secondary higher alcohol sulfate, primary higher alkyl sulfonate, secondary higher alkyl sulfonate, higher alkyl disulfonic acid Salt, sulfonated higher fatty acid salt, higher fatty acid sulfate ester salt, higher fatty acid ester sulfonate, higher alcohol ether sulfate, higher alcohol ether sulfonate, higher fatty acid amide alkylolated sulfate, alkylbenzene sulfone Anionic surfactants such as acid salts, alkylphenol sulfonates, alkylnaphthalenesulfonates, and alkylbenzimidazolesulfonates; and nonionic surfactants such as polyoxyethylene alkyl ethers and polyoxyethylene alkyl phenols. Ethers, polyoxyethylene fatty acid esters, polyoxyethylene fatty acid amide ether, polyhydric alcohol fatty acid ester. Polyoxyethylene polyhydric alcohol fatty acid ester, fatty acid sucrose ester, alkylolamide, polyoxyalkylene block copolymer and the like are used. These surfactants are
Generally, it is used in an amount of 1.0 g or less per liter of the aqueous dispersion.

As the water-miscible organic solvent, methanol,
Alcohol solvents such as ethanol, propanol and butanol; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ether solvents such as tetrahydrofuran and dioxane; ester solvents such as ethyl acetate and butyl acetate; methyl cellosolve and ethyl Cellosolve solvents such as cellosolve, propyl cellosolve and butyl cellosolve; carbitol solvents such as methyl carbitol, ethyl carbitol and butyl carbitol. These water-miscible organic solvents are generally used in an amount of 45 ml or less per liter of the aqueous dispersion.

[Container Substrate] The present invention is particularly advantageously applied to the purpose of a cold end coat for a glass bottle among various packaging containers. Accordingly, although this example will be described below, the present invention is also useful for forming a hydrophilic and scratch-resistant coating on the outer surface of another packaging container such as a plastic container or a metal can. Should be understood.

Glass bottles have the advantage of being chemically durable, non-breathable, sanitary, and have a high preservability of the contents, but are heavy, fragile and easily broken. There is a disadvantage that. Efforts have been made to reduce the weight of the former disadvantage, and for the purpose of improving the strength to improve the latter defect, it is important to improve the scratch resistance of the surface. Coating required.

Although the glass composition of the glass bottle is not particularly limited, so-called soda-lime glass is generally used. In the production of the glass bottle, the glass is melted at a high temperature of 1500 ° C. or more in a melting chamber, and the throat, the working chamber, and the hoar hearth are manufactured. And gradually cool down on the way, and
Cut into candy-like glass lump (gob) of about 100 ° C,
It is put into the mold of the bottle making machine, and the molding is completed through the rough mold and the finish mold. In the present invention, the coating treatment is performed immediately after the bottle is formed on the way of the conveyor from the lehr.

The types of glass bottles include milk bottles, bottles for soft drinks such as cola, ramune and juice, soy sauce,
Examples include bottles for seasonings such as vinegar, and bottles for sake such as beer, whiskey, and sake. The present invention is particularly suitable for use in lightweight one-way bottles. The glass bottle serving as the substrate may be colorless and transparent, or may be made of a brown or green ultraviolet blocking glass for filling contents whose flavor is impaired by ultraviolet rays.

The present invention is also applicable to metal oxide-coated glass bottles that can be used repeatedly as returnable bottles. The formation of a coating of a metal oxide on the surface of a glass bottle is generally called a hot end coat, and is performed immediately after the bottle is formed on a conveyor to a lehr.

Examples of the metal oxide include oxides of titanium and tin. The metal oxide layer is preferably provided as a continuous layer having a thickness of 150 to 480 angstroms. Hot-end coating is a type of chemical vapor deposition (CVD) in a reaction chamber installed in front of an annealing furnace.
Generally, it is performed by bringing a glass bottle at a temperature of 500 to 650 ° C. into contact with a gas containing the metal component. As the metal component, an organic titanium compound, for example, tetraisopropyl titanate, tetrabutyl titanate, tetratitanate, tetraethyl titanate, tetraethylhexyl titanate, tetranonyl titanate and the like, and chlorides such as titanium tetrachloride and tin tetrachloride are used. You.

[Coating and Production Thereof] In the hydrophilic coating of the present invention, a coating composed of a hydrophilic polymer is generally provided with a thickness of 0.03 to 5.0 μm, preferably 0.1 to 1.0 μm. Good to be. When the thickness of the coating is less than the above range, the hydrophilicity is insufficiently imparted and the film strength is low and not practical as compared with the case where the thickness is within the above range. on the other hand,
Even if the thickness of the coating exceeds the above range, there is no particular advantage as compared with the case where the thickness is within the above range. On the contrary, the original transparency of the glass bottle is lost, the processing cost is increased, and the productivity is increased. Is undesirably reduced.

In the present invention, the ratio of the particle diameter of the solid lubricant / the thickness of the hydrophilic polymer is generally 1.1 to 3.
5, preferably in the range of 1.3 to 2.5. When the ratio of the particle diameter of the solid lubricant / the thickness of the hydrophilic polymer is less than the above range, the activity tends to decrease or the scratch resistance tends to decrease as compared with the case where the ratio falls within the above range, which is not preferable. . On the other hand, when this ratio exceeds the above range, the film strength is lowered and the hydrophilicity becomes insufficient, which is not preferable.

The treatment for forming the coating on the outer surface of the glass bottle is performed as a cold end coat. Generally, the coating composition described above is applied to a glass bottle having a temperature of 80 to 150 ° C. which has come out of an annealing furnace. Ie, by spraying an aqueous dispersion.

In the present invention, the thickness of the aqueous polymer film formed on the surface of the glass bottle may be very small.
The coating treatment by spraying is advantageous in that it can be performed in a significantly short time. For example, as shown in the examples described later,
It can be performed within a short time of about 0.1 to 1.0 second. For this reason, the coating treatment of the present invention also has the advantages of high productivity and low processing cost.

[0041]

The present invention will be further described with reference to the following examples, but it should not be construed that the invention is limited to the examples. Various measurements in the examples were performed as follows.

[Slipperiness test] 2
The two glass bottles were arranged in a side-by-side relationship, one glass bottle was placed on the two glass bottles, and the angle at which the upper glass bottle slipped was determined. It shows that the smaller the angle, the better the slipperiness.

[Scratch resistance] Two glass bottles are supported by upper and lower supports in a vertical relationship, and a load of 0.4 to 5 MPa is applied to the upper support, and the lower support is The glass bottle was moved in the horizontal direction under a load of, and the glass bottles were rubbed with each other. Eighteen samples were used in one test, and the results were expressed as a percentage of the number of scratch-free materials.

[Label sticking property] A starch paste was applied to the back side, and a label, which had been pre-grained on the outer side, was pasted on a glass bottle, and the paste was dried for 24 hours at room temperature to dry the paste.
The label was peeled off and the area that did not peel off was indicated as a percentage. The larger the value, the better the label sticking property.

[Water wettability]
After immersing in water at 5 ° C. for 5 seconds and holding the glass bottle taken out of the water in an upright state for 5 seconds, evaluation was made according to the following evaluation criteria from the state of adhesion of water droplets. ○ 全体 The entire surface of the glass bottle is smoothly wet with water, and no water droplets are observed. △ 付 着 Adhesion of water droplets is observed at various places in the glass bottle. × 付 着 Water droplets are observed all over the glass bottle.

[Stain Adhesion] A solution of 1% by weight of lanolin was homogenized, and a completely emulsified solution at a temperature of 60 ° C. was brought into contact with a glass bottle by an immersion method. The condition was evaluated according to the following evaluation criteria. ○ 汚 れ No or little adhesion of dirt to glass bottles. △ 汚 れ Adhesion of dirt to the glass bottle is observed in some places. × か な り Adhesion of dirt to the glass bottle is considerable.

[Water Resistance] The glass bottle coated with the cold end was immersed in water at 80 ° C. for 30 minutes, pulled up from the water, and the state of the coating was evaluated according to the following evaluation criteria. ○ ‥ There is no or almost no change in the coating. △ 一部 Partial dissolution or whitening is observed in the coating. × ‥ Coating dissolution is remarkable.

[Surface Condition] The glass bottle coated with the cold end was visually observed with respect to the untreated glass bottle, and evaluated according to the following evaluation criteria. ○ 殆 ど There is almost no fogging or unevenness in the coating. △ ‥ The coating is slightly cloudy or uneven. × 著 し い The coating is extremely cloudy or uneven.

The materials used are as follows. I Film-forming material (1) Water-dispersible cellulose As the water-dispersible cellulose, a composition of 89% by weight of ground cellulose and 11% by weight of carboxymethylcellulose (CMC) was used. (2) Polyvinyl alcohol (PVA) Polyvinyl alcohol having an average polymerization degree of 500 and a saponification degree of 98 mol% was used. (3) Cellulose acetate Cellulose acetate having a degree of esterification of 99% was used. (4) Cellulose xanthate Viscose obtained by reacting carbon disulfide with alkali cellulose was used. (5) Polyethylene wax An emulsion of polyethylene wax was used.

Reference Example 1 0.2 of water-dispersible cellulose
Using a weight% aqueous dispersion, a glass plate was immersed in this aqueous dispersion to form a film on the glass plate, and the coated glass plate was subjected to the various tests described above. The film strength is measured according to JIS
It was evaluated by a method according to K5400 (General Paint Test Method). That is, the state of scratch generation of the film by a pencil scratch test using a 4H pencil and the film adhesion by a cross-cut tape test were comprehensively evaluated. ○ ‥ No change was observed in the pencil scratch test and the cross cut tape test. △ ‥ The film was partially removed by the pencil scratch test. Alternatively, a part of the film is peeled off by a cross cut tape test. × ‥ Most of the film is scraped off by the pencil scratch test.
Alternatively, most of the film is peeled off by the cross-cut tape test. Table 1 shows the obtained results.

Reference Example 2 A coated glass plate was produced in the same manner as in Reference Example 1 except that a 0.2% by weight aqueous solution of PVA was used instead of the water-dispersible cellulose, and a test was conducted in the same manner as in Reference Example 1. Was done. Table 1 shows the obtained results.

Reference Example 3 A coated glass plate was produced in the same manner as in Reference Example 1 except that a 2-butane solution having a cellulose acetate concentration of 0.2% by weight was used instead of the water-dispersible cellulose. The test was performed as in Example 1. Table 1 shows the obtained results.

Reference Example 4 The procedure of Reference Example 1 was repeated except that an aqueous solution of 0.2% by weight of cellulose xanthate (in terms of cellulose) was used instead of the water-dispersible cellulose, and the formed film was treated with an aqueous sulfuric acid solution. Similarly, a coated glass plate was manufactured, and a test was performed in the same manner as in Reference Example 1. Table 1 shows the obtained results.

Reference Example 5 A coated glass plate was produced in the same manner as in Reference Example 1 except that an aqueous emulsion containing 0.2% by weight of polyethylene wax was used instead of the water-dispersible cellulose. The test was performed similarly. Table 1 shows the obtained results.

[0055]

[Table 1] Reference Example 1 2 3 4 5 Lubricity △ △ △ △ ○ Film strength ○ △-○ △ Label sticking ○ ○ × ○ × Water wettability ○ ○ △ ○ × Stain resistance ○ ○ × ○ × Surface condition ○ ○ ○ △ ○ Water resistance ○ △ ○ ○ △

Conventionally, polyethylene wax, which has been widely used as a cold end coat for glass bottles, is excellent in lubricity, but is inferior in film strength, and in terms of label sticking property, water wettability, and stain resistance. I failed. on the other hand,
Although the water-dispersible cellulose was slightly inferior in terms of lubricity, it passed all points in film strength, label sticking property, water wettability, and stain adhesion.

Example 1 Polyethylene wax having an average particle diameter of 0.6 μm and a melting point of 115 ° C. was used as solid lubricant particles. After the above-mentioned water-dispersible cellulose is dispersed in water and homogenized, the polyethylene wax is further dispersed, and the water-dispersible cellulose has a concentration of 2 g / L,
An aqueous coating solution containing polyethylene wax at a concentration of 0.4 g / L was prepared.

Internal volume 100 m maintained at a temperature of 110 ° C.
The glass bottle for beverage having a height of 1 mm and a height of 130 mm was kept upright, the glass bottle was rotated (spinned) at a speed of 240 rpm, and the aqueous dispersion was sprayed on the glass bottle for 0.5 second through a spray nozzle.

The thickness of the formed hydrophilic film is 0.3 μm,
The area ratio of the polyethylene wax exposed on the hydrophilic film surface was 11%. FIG. 2 shows a scanning electron micrograph of the surface of the formed film. From FIG. 2, it can be observed that the polyethylene wax particles are protruding from the hydrophilic coating made of water-dispersible cellulose. About the obtained coated glass bottle, it tested about each item mentioned above,
Table 2 shows the obtained results. The test for the scratch resistance was performed under a load of 5 MPa.

Example 2 Instead of the aqueous dispersion of Example 1, the following composition was used: water-dispersible cellulose 2 g / L polyethylene wax 0.2 g / L potassium oleate 0.05 g / L isobutyl alcohol 20 ml / L aqueous solution A coated glass bottle was manufactured in the same manner as in Example 1 except that the dispersion time was changed to 0.75 seconds using the dispersion liquid. The thickness of the formed hydrophilic film was 0.4 μm, and the area ratio of polyethylene wax exposed on the hydrophilic film surface was 8 μm.
%Met. The obtained coated glass bottle was tested in the same manner as in Example 1, and the obtained results are shown in Table 2.

Example 3 As the solid lubricant particles, polyethylene wax having an average particle size of 1.0 μm and a melting point of 102 ° C. was used. Instead of the aqueous dispersion of Example 1, the following composition water-dispersible cellulose 5 g / L A coated glass bottle was produced in the same manner as in Example 1 except that an aqueous dispersion of polyethylene wax 0.5 g / L was used. The thickness of the formed hydrophilic film was 0.6 μm, and the area ratio of the polyethylene wax exposed on the surface of the hydrophilic film was 6%. The obtained coated glass bottle was tested in the same manner as in Example 1, and the obtained results are shown in Table 2.

Example 4 Carnauba wax having an average particle size of 2.0 μm and a melting point of 84 ° C. was used as solid lubricant particles, and instead of the aqueous dispersion of Example 1, the following composition was used. L, Carnauba wax A coated glass bottle was produced in the same manner as in Example 1 except that an aqueous dispersion of 1.0 g / L was used. The thickness of the formed hydrophilic film was 0.6 μm, and the area ratio of carnauba wax on the surface of the hydrophilic film was 7%. The obtained coated glass bottle was tested in the same manner as in Example 1, and the obtained results are shown in Table 2.

Comparative Example Instead of the aqueous dispersion of Example 1, 2 g / L of polyethylene wax having a melting point of 104 ° C. and an average dispersed particle size of 0.2 μm, and potassium oleate of 0.6
A coated glass bottle was manufactured in the same manner as in Example 1 except that the spray time was 0.5 seconds using an emulsion solution consisting of g / L. The thickness of the formed film is 0.3
μm. The obtained coated glass bottle was tested in the same manner as in Example 1, and the obtained results are shown in Table 2.

[0064]

[Table 2]

[0065]

According to the present invention, a coating is formed on the outer surface of a container, in which solid lubricant particles are exposed from a film mainly composed of a polymer having a hydrophilic group. The present invention can provide a packaging container, particularly a glass bottle, which has excellent labeling properties, water wettability, stain resistance, and water resistance as well as excellent hydrophilicity and lubricity.
According to the present invention, there is also an advantage that the above-mentioned coating can be easily applied to the surface of a glass bottle by a cold end coat (CEC), so that the productivity is excellent and the production cost is low.

[Brief description of the drawings]

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

FIG. 2 is an electron micrograph showing a particle structure of solid lubricant particles on a coating surface.

[Explanation of symbols]

 Reference Signs List 1 base material 2 hydrophilic film 3 solid lubricant particles 4 film surface

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C10M 107/38 C10M 109/00 109/00 145/04 145/04 145/12 145/12 145/40 145 / 40 149/06 149/06 169/04 169/04 C10N 20:06 Z // C10N 20:06 30:06 30:06 50:08 50:08 B65D 1/00 BF term (reference) 3E033 AA01 BA01 BA10 BA14 BA15 BB04 BB08 CA10 CA20 EA07 4H104 BE11A CA01A CB02C CB07C CB08A CB08C CB19C CD01A CD02A CE03C DA05A EA08A LA03 QA12 RA01 4J012 CB011 BA111 BA171 BA191 BA212 CB022 CB062 CB061 CB062 CB051 CB06 KA09 KA20 MA08 MA10 NA05 NA06 NA09 NA11 PB04 PC02 PC03

Claims (10)

[Claims] 1. A packaging container, wherein a coating is formed on the outer surface of the container, the solid lubricant particles protruding from a film mainly composed of a polymer having a hydrophilic group. 2. The packaging container according to claim 1, wherein the solubility parameter value (Sp value) of the polymer having a hydrophilic group is in a range of 25 or more. 3. The packaging container according to claim 1, wherein the polymer having a hydrophilic group is cellulose or a cellulose derivative. 4. The packaging container according to claim 1, wherein the solid lubricant comprises an olefin resin or a high melting point wax. 5. The packaging container according to claim 1, wherein the solid lubricant is a polyethylene wax or a modified polyethylene wax. 6. The packaging container according to claim 1, wherein the container is a glass bottle. 7. The thickness of the film is 0.03 to 5.0 μm.
The packaging container according to any one of claims 1 to 6, wherein: 8. The packaging container according to claim 1, wherein the ratio of lubricant particle diameter / film thickness is in the range of 1.1 to 3.5. 9. A packaging container according to claim 1, wherein the solid lubricant particles are present in an amount of 3 to 70% by weight per polymer having a hydrophilic group. 10. The packaging container according to claim 1, wherein the proportion of the lubricant particles protruding from the head to the surface is 1 to 60% or more.