JP6406383B1 - Structure having a two-layer lubricating film - Google Patents

Abstract

The present invention provides a structure having a lubricating film on its surface that exhibits excellent lubricity over a long period of time for contents containing a large amount of surfactant, and particularly viscous contents. In a structure consisting of a base material and a lubricating film formed on the surface of the base material, the lubricating film includes a lubricating support layer located on the surface side of the base material, and a lubricating support. The lubricating functional layer 3b located on the layer 3a has a two-layer structure, and the lubricating functional layer 3b is formed of a gelling agent-containing film or a non-Newtonian liquid film. [Selection] Figure 1

Description

  The present invention relates to a structure composed of a base material molded into a predetermined shape and a two-layered lubricating film formed on the surface thereof, and more particularly to a structure suitably used as a pouch.

  In a container in which a fluid content is stored, dischargeability to the content is required regardless of the material of the container. In the case of containing a low-viscosity liquid such as water, such dischargeability is hardly a problem, but for example, in the case of foods such as curry, viscous substances represented by conditioners and shampoos, etc. Whether it is a plastic container or a glass container, this discharge is a very serious problem. That is, such contents are not quickly discharged by tilting the container, and adhere to the container wall, and thus cannot be used up to the end. Especially, a considerable amount of contents are placed at the bottom of the container. Remains without being discharged.

Recently, many techniques for improving the slipperiness with respect to viscous substances by forming a lubricating film made of an oily liquid or the like on the surface of a molded body such as a container have been proposed.
According to such a technique, compared with the case where an additive such as a lubricant is added to the synthetic resin forming the surface of the molded body, the slipperiness can be drastically improved. When the slipperiness with respect to the contents is improved by such a lubricant film, there is a problem that the function of the lubricant film is consumed in a short period of time. In many cases, such problems are caused by the fact that when the contents are repeatedly discharged from the container, the oily liquid forming the lubricating film is gradually discharged together with the contents and is consumed.

As means for solving the above-mentioned shortening of the service life due to wear of the lubricating film, for example, Patent Document 1 discloses that the lubricating film is formed of a non-Newtonian aqueous liquid such as an aqueous polymer solution or an aqueous polymer dispersion solution. Proposed by people.
Patent Document 2 also proposes a means for forming a lubricating film with water thickened by a thickener by the present applicant.

  The lubricating films formed in Patent Documents 1 and 2 above all have a thixotropic property in the liquid forming the lubricating film, and are high when the contents are discharged on the surface in contact with the contents. The shearing force is applied and the slipping with respect to the contents is exerted by flowing with the contents, but since the shearing force is not applied to the inner surface of the container which is the base of the lubricating film, it shows high viscosity and remains on the container side. As a result, the consumption of the lubricating film is effectively suppressed.

However, the above-mentioned means have sufficient lubricity (slipperiness) for contents containing oil such as curry and Chinese seasoning and contents containing a large amount of surfactant such as conditioner and shampoo. In addition, there is a problem that the contents easily adhere and remain in the container, and the useful life thereof is insufficient. These contents probably have a high affinity between the contents and the lubricating film, which seems to prevent the improvement of slipperiness. Further, since the liquid forming the lubricating film is taken into the contents while being filled and stored in the container, it is considered that the lubricity cannot be sufficiently exhibited.
Furthermore, even when a container such as a pouch is filled with a viscous content, the life of the lubricating film tends to be unsatisfactory. Probably, containers such as pouches are often loaded and stored, and the loading pressure is applied to the lubricating film through the contents, which results in the contents and the lubricating film being integrated, resulting in lubrication of the lubricating film. It is considered difficult to maintain the sex for a long time.

Further, in Patent Document 3, the applicant also proposes that a lubricating film be formed by a suspension composed of a dispersion medium and a dispersoid (specifically, an aqueous liquid and an oily liquid) that are incompatible with each other. Has been.
In such a lubricating film, when a certain time elapses after the contents are filled, the suspension is phase-separated into a dispersion medium and a dispersoid, and a two-layer liquid film is formed. As a result, for example, when the content is aqueous, by setting the upper liquid film of the lubricating film to be an aqueous liquid, the wettability with the content is enhanced, and at the interface between the two liquid films. By slipping, excellent slipperiness with respect to the contents is exhibited.
However, even in such a two-layer lubricating film, there is still room for improvement in terms of its life. That is, since there is no affinity between the two liquid films constituting the lubricating film, the upper liquid film is integrated with the contents over time, and eventually the same as the case where the lubricating film is a single layer. Because. In addition, in the case of a pouch filled with the above-described surfactant-rich contents or viscous contents, such an upper liquid film disappears in a very short time.

Furthermore, the present applicant has previously proposed that the lubricating film is formed of a so-called oil gel (Japanese Patent Application No. 2017-9219).
Such a method has the advantage that it has a long useful life and excellent transparency, but it is suitable for conditioners containing a large amount of surfactants and viscous contents filled in pouches. Further improvements are needed in terms of overall lubricity and life.

JP 2017-13369 A Japanese Unexamined Patent Publication No. 2017-12091 Japanese Patent No. 5968491

Accordingly, an object of the present invention is to provide a lubricating film on the surface that exhibits excellent lubricity over a long period of time for contents containing oil, contents containing a large amount of surfactant, and particularly viscous contents. By providing a structure.
Another object of the present invention is to provide a structure in which the excellent slipperiness of the lubricating film can be stably maintained over a long period of time even when used as a pouch that accommodates viscous contents.

According to the present invention, in the structure composed of the base material and the lubricating film formed on the surface of the base material,
The lubricating film has a two-layer structure of a lubricating support layer located on the substrate surface side and a lubricating functional layer located on the lubricating support layer,
A structure is provided in which the lubricating functional layer is made of a gelling agent-containing film or a non-Newtonian liquid film.

In the structure of the present invention,
(1) The gelling agent-containing film or non-Newtonian liquid film forming the lubricating functional layer is an aqueous layer, and the lubricating support layer is an oily layer,
(2) The aqueous layer is formed of water thickened with a water-soluble polymer,
(3) The water-soluble polymer is at least one selected from the group consisting of xanthan gum, guar gum, gellan gum, pectin, carboxymethylcellulose, gelatin, alginic acid, agar, and carrageenan.
(4) The gelling agent contained in the gelling agent-containing film is an agent that gels by taking in ions contained in the fluid in contact with the lubricating functional layer,
(5) The gelling agent-containing film is formed of a sodium alginate aqueous solution and a carrageenan aqueous solution,
(6) The gelling agent-containing film or non-Newtonian liquid film forming the lubricating functional layer is an oily layer, and the lubricating support layer is an aqueous layer,
(7) The oily layer contains a thickener compatible with the oily liquid,
(8) The base material has a resin surface;
(9) The base material has the form of a packaging container;
(10) The packaging container is a pouch,
Is preferred.

An important feature of the structure of the present invention is that the lubricating film is functionally separated into two layers: a lubricating support layer formed on the surface of the substrate and a lubricating functional layer formed on the lubricating support layer. In particular, the lubricating functional layer, that is, the layer in contact with the fluid flowing on the lubricating film is formed from a gelling agent-containing film or a non-Newtonian liquid film.
That is, when the lubricating functional layer is formed of a non-Newtonian liquid film, the lubricating functional layer serves as a barrier, and prevents the lubricating support layer from being taken in and lost in the fluid that contacts the surface of the lubricating functional layer. . That is, the non-Newtonian liquid film forming the lubricating functional layer exhibits thixotropy, so that no shear force is applied and the fluid is merely in contact with the lubricating functional layer. The functional layer hardly exhibits fluidity, and as a result, even when the liquid contains a large amount of a surfactant component or is a highly viscous fluid, it can be mixed and integrated with the lubricating functional layer. It is effectively suppressed, and disappearance or consumption after being taken into the liquid is effectively prevented, and further, the disappearance of the lower lubricating support layer is surely prevented. In addition, when the fluid flows on the lubricating functional layer, the interface portion with the lubricating support layer is peeled off, or the fluid and the lubricating functional layer flow together due to the fluidity of the lubricating support layer. On the other hand, excellent slipperiness will be exhibited.
In addition, even when the lubricating functional layer is formed of a gelling agent-containing film (that is, gel), the lubricating functional layer or the lubricating support layer below it is taken in by the fluid flowing on the surface and disappears. The liquid flows along the interface between the lubricating functional layer and the lubricating support layer together with the gel of the lubricating functional layer, or the fluid and the lubricating functional layer flow together due to the fluidity of the lubricating support layer. Thus, the fluid flowing on the surface can be discharged without remaining.

  As described above, according to the present invention, the lubrication film is formed by the two layers of the lubrication functional layer and the lubrication support layer as described above, thereby effectively avoiding a decrease in life due to being taken into the fluid flowing over the lubrication film. In addition, it exhibits excellent lubricity against the fluid flowing over it. For example, when this structure is used as a container such as a viscous paste-like fluid containing oil such as curry or a pouch containing a fluid containing a large amount of surfactant such as a conditioner, The excellent lubricity exhibited by the lubricating film can be maintained over a long period of time.

The schematic sectional side view for demonstrating the surface form of the structure of this invention. The schematic sectional side view in which the fluid is contacting the lubricating film of the structure surface of this invention.

  Referring to FIGS. 1 and 2, the structure of the present invention generally indicated by 10 is formed of a base material 1 molded into a predetermined shape and a lubricating film 3 formed on the surface thereof. . In the present invention, the lubricating film 3 is composed of two layers of a lubricating support layer 3a on the base material 1 and a lubricating functional layer 3b provided on the lubricating support layer 3a, and a fluid 20 flowing on this surface. (Refer FIG. 2) It shows lubricity.

  As long as the base material 1 can hold the lubricating film 3 (particularly, the lubricating support layer 3a) as described above on its surface, the material is not particularly limited, and is made of synthetic resin, glass, or metal. From the viewpoint of wettability, a synthetic resin is preferable when the lubricating support layer is oily, and glass or metal is preferable when it is aqueous, from the viewpoint of wettability.

  The synthetic resin (hereinafter referred to as the base resin) may be any moldable thermoplastic resin or thermosetting resin, but is generally easy to mold and effective for holding the lubricating support layer 3a. A thermoplastic resin is preferable in that a rough surface can be easily formed.

As such a thermoplastic resin, the following can be illustrated, for example.
Olefin resins such as low density polyethylene, high density polyethylene, polypropylene, poly 1-butene, poly 4-methyl-1-pentene or α-olefins such as ethylene, propylene, 1-butene and 4-methyl-1-pentene Random or block copolymers, cyclic olefin copolymers, etc .;
Ethylene / vinyl copolymers, such as ethylene / vinyl acetate copolymer, ethylene / vinyl alcohol copolymer, ethylene / vinyl chloride copolymer, etc .;
Styrenic resin such as polystyrene, acrylonitrile / styrene copolymer, ABS, α-methylstyrene / styrene copolymer, etc .;
Vinyl resins such as polyvinyl chloride, polyvinylidene chloride, vinyl chloride / vinylidene chloride copolymers, polymethyl acrylate, polymethyl methacrylate, etc .;
Polyamide resin, for example, nylon 6, nylon 6-6, nylon 6-10, nylon 11, nylon 12, etc .;
Polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate, and copolyesters thereof;
Polycarbonate resin;
Polyphenylene oxide resin;
Biodegradable resins, such as polylactic acid;
Of course, as long as the moldability is not impaired, a blend of these thermoplastic resins can also be used as the base resin.

  In the present invention, among the thermoplastic resins described above, olefinic resins and polyester resins that are suitably used in the field of packaging materials are desirable. In particular, when the structure 10 is used as a bag-like container such as a pouch. For this, an olefin resin is most suitable.

  Further, the base material 1 may have a single layer structure of the thermoplastic resin as described above, or may be a laminate of the thermoplastic resin and paper, and a gas barrier resin layer or the like may be used. The substrate 1 may have a laminated multilayer structure, and may further have a structure in which the substrate 1 is laminated on a metal foil or the like.

  In the base material 1 as described above, the surface on which the lubricating film 3 (the lubricating support layer 3a and the lubricating functional layer 3b) is formed is in view of the retaining property of the lubricating film 3 formed from a fluid, particularly the lubricating support layer 3a. The surface may be rough. Such a rough surface can be formed by a known means depending on the form of the substrate 1. For example, the rough surface can be formed by blending and molding inorganic oxide particles such as silica in the resin forming the surface of the substrate 1. Moreover, when the base material 1 has the form of a film, a rough surface can also be formed by surface processing, such as a blast process.

  As already described, the lubricating film 3 is formed of the lubricating support layer 3a and the lubricating functional layer 3b, and these layers are composed of an aqueous layer mainly composed of water and various oily liquids such as various aqueous solutions. Any oil-based layer as a main component may be used.

  However, the lubricating functional layer 3b provided on the surface of the lubricating support layer is formed from an aqueous or oily gelling agent-containing film or a non-Newtonian liquid film.

  When the lubricating functional layer 3b is an aqueous layer, the non-Newtonian liquid film is formed from an aqueous non-Newtonian film, and when the lubricating functional layer 3b is an oily layer, it is formed from an oily non-Newtonian liquid. Is done.

As the aqueous non-Newtonian liquid, a high-viscosity aqueous solution prepared by blending a water-soluble polymer is used.
Examples of such water-soluble polymers include the following.
Natural polymers such as guar gum, xanthan gum, locust bean gum, quince seed gum, carrageenan, pectin, mannan, starch, sodium alginate, agar, etc. Plant polysaccharide polymers; xanthan gum, succinoglycan, curdlan, hyaluronic acid , Microbial polysaccharide polymers such as dextran; plant protein polymers such as gelatin, casein, albumin and collagen;
Semi-synthetic polymers such as cellulose polymers such as methylcellulose, ethylcellulose, hydroxycellulose, hydroxypropylcellulose, carboxymethylcellulose, and cationized cellulose; starch-based polymers such as solubilized starch and carboxymethylstarch, propylene glycol alginate, etc. Alginic acid polymers and polysaccharide derivative polymers;
Synthetic polymers, for example, vinyl polymers such as polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylic acid, polyacrylamide and derivatives thereof; polyethylene oxide, polyethylene oxide-polypropylene oxide block copolymers;

  Among the above water-soluble polymers, natural polymers are preferable from the viewpoint of influence on the environment, and guar gum, xanthan gum, sodium alginate, and carrageenan are preferable from the viewpoint that the thickening effect is particularly high.

As the oily non-Newtonian liquid, oily liquids prepared by blending a thickener with various base oils are used.
Typical examples of such base oils include liquid paraffin, synthetic paraffin, fluorinated liquid, fluorinated surfactant, silicone oil, fatty acid triglyceride, various vegetable oils, and the like. When the fluid 20 flowing on the lubricating film 3 is food, edible oil or fatty acid triglyceride is suitable.
Specific examples of such edible oils include soybean oil, rapeseed oil, olive oil, rice oil, corn oil, ben flower oil, sesame oil, palm oil, castor oil, avocado oil, coconut oil, almond oil, walnut oil, and bean oil. And salad oil.

  The thickener itself has a functional group or metal salt capable of forming a hydrogen bond or a coordination bond, and is compatible with the above base oil to form a network in an oily liquid. It is. Typical examples of such functional groups include hydroxyl groups, carboxyl groups, and metal salts that include polyvalent ions such as aluminum, zinc, and magnesium.

Examples of such thickening agents include 12 hydroxystearic acid, dibenzylidene sorbitol, calcium dehydroabietic acid, amino acid derivatives, alkyl phosphates, cholesterol derivatives, phenolic ring oligomers, anthracene derivatives, triphenylamine derivatives, Examples include quaternary ammonium salt derivatives, vitamin H derivatives, cholic acid derivatives butyrolactone derivatives, urea derivatives, sugar fatty acid esters, fluorinated alkyls, modified silicones, metal soaps, and waxes.
Examples of the amino acid derivatives include dibutyllauroylglutamide and dibutylethylhexanoylglutamide; modified silicones as side chain alkyl-modified silicones; metal soaps as fatty acids such as stearic acid and isostearic acid; and aluminum and zinc Fatty acid metal salts and waxes composed of polyvalent ions such as straight chain paraffin and polyethylene hydrocarbons, higher alcohols such as cetanol and stearyl alcohol, fatty acids such as stearic acid, hydrogenated castor oil, hydrogenated Jojoba oil is typical.

  The aqueous or oily non-Newtonian fluid as described above is, for example, a water-soluble polymer, a thickening stabilizer or a viscous so that the viscosity (25 ° C.) measured at a rotation speed of 20 rpm is 690 mPa · s or more. An agent is blended.

Further, when the lubricating functional layer 3b is a gelling agent-containing film, the gelling agent blended in the film contains metal ions such as Ca ions (normal foods and the like) in the fluid 20 in contact with the lubricating functional layer 3b. It is an agent that forms a cross-linked product (that is, a gel) by reacting with most of the detergents, for example, sodium alginate, carrageenan, polyvinyl alcohol or a copolymer thereof. Such a gelling agent can be used as it is in the form of an aqueous solution or an oily liquid dissolved in the aforementioned base oil, depending on its solubility (water-soluble or oil-soluble). Appropriate amounts can be blended and used in Newtonian fluids or oily non-Newtonian fluids.
Such a gelling agent is usually blended in the lubricating functional layer 3b in an amount of about 0.1 to 10% by mass.
In the present invention, the gelling agent-containing liquid is most preferably an aqueous type sodium alginate or an aqueous solution of carrageenan in terms of gel formation.

The lubricating functional layer 3b described above is usually formed on the surface of the substrate 1 in an amount of 0.1 to 100 g / m ² .

  The formation of the lubricating functional layer 3b is performed by applying it to the surface of the lubricating support layer 3a formed into a predetermined shape by spraying or the like.

  In the present invention, the lubricating functional layer 3b formed on the lubricating support layer 3a described below exhibits excellent lubricity (slidability) with respect to the fluid 20 in contact with the surface, and at the same time is integrated with the fluid 20 It is provided in order to suppress disappearance due to crystallization and to exhibit lubricity over a long period of time. On the other hand, the lubrication support layer 3a is a layer provided to develop lubricity, and is peeled off at the interface between the lubrication function layer 3b and the lubrication support layer 3a or is liquid by utilizing the fluidity of the lubrication support layer. 20 can flow.

  Such a lubricating support layer 3a, like the above-described lubricating functional layer 3b, includes an aqueous type and an oil type, and any type can be used. However, when the lubricating support layer 3a is oily, An aqueous type is preferred, and when the lubricating support layer 3a is aqueous, an oily type is preferred. That is, when the lubricating support layer 3a and the lubricating functional layer 3b are the same type, the two layers 3a and 3b are likely to be integrated, and the functional separability of these layers may be impaired.

Such an aqueous or oily lubricating support layer 3a can be formed of any of the above non-Newtonian liquids, but may be formed of water alone or oil alone. In particular, formation of water alone or oil alone is preferable in terms of imparting lubricity.
Examples of such non-Newtonian liquids include aqueous or oily non-Newtonian fluids that can be used to form the lubricating functional layer 3b described above.

The function of the lubricating film 3 composed of the lubricating support layer 3a and the lubricating functional layer 3b is as follows.
Referring to FIG. 2, when the lubricating functional layer 3b is formed of a non-Newtonian fluid, the shear force is not applied when the fluid 20 is simply in contact with the layer 3b. Hardly shows fluidity and is stably held on the lubricating support layer 3a. Therefore, even if the fluid 20 contains a large amount of surfactant (for example, when the fluid 20 is a conditioner) or even if the fluid 20 is a fluid such as a viscous paste-like curry, Since the mixed integration of the layer 3b and the liquid 20 is effectively suppressed, the lubricating functional layer 3b is stably maintained for a long time without disappearance or wear, and the lubricating functional layer 3b serves as a barrier. Similarly to the initial stage, 3a is held stably.
On the other hand, when the fluid 20 flows on the lubricating functional layer 3b, the lubricating functional layer 3b is peeled off at the interface portion with the lubricating supporting layer 3a, or the liquid and the lubricating functional layer are separated by the fluidity of the lubricating supporting layer 3a. It flows together, and excellent slipperiness with respect to the fluid 20 is exhibited.
As described above, the lubricating functional layer 3b not only exhibits excellent lubricity to the liquid 20, but since both the lubricating functional layer 3b and the lubricating support layer 3a are stably held, the lubricity is not impaired. Maintained for a long time.

Also, when the lubricating functional layer 3b is formed from a gelling agent-containing fluid, the gel formed is a crosslinked body, and is a dense solid or semi-solid having a three-dimensional network structure, Since this gel serves as a barrier and mixing and integration of the lubricating functional layer 30b and the liquid 20 is effectively suppressed, the lubricating functional layer 3b as well as the lubricating supporting layer 3a is not lost or consumed as described above. It will be kept stable over a long period of time.
Furthermore, the lubricating functional layer 3b reacts with metal ions such as Ca ions (mostly contained in ordinary foods and detergents) in the fluid 20 as typified by sodium alginate and carrageenan. (I.e., a gelling agent-containing liquid that forms a gel), contact with the fluid 20 flowing on the gelling agent-containing liquid causes a metal ion in the vicinity X of the interface between the liquid 20 and the lubricating functional layer 3b. Is taken in to form a gel, so that a gel that becomes the same barrier as described above is obtained.
Further, when the liquid 20 flows in a state where such a gel is formed, the lubricating functional layer 3b peels off from the lubricating support layer 3a, or the liquid and the lubricating functional layer flow together due to the fluidity of the lubricating support layer 3a. Become. In particular, when the lubricating functional layer 3b and the lubricating support layer 3b are different in solubility (aqueous or oily), the separation of the lubricating functional layer 3b and the lubricating support layer 3a easily proceeds, so that the liquid 20 is quickly lubricated. It flows along with the functional layer 3b.

  Thus, in the present invention, even when the lubricating functional layer 3b is formed from either a non-Newtonian liquid or a gelling agent-containing fluid, regardless of the composition and physical properties of the liquid 20 flowing thereover, The lubricating functional layer 3b and the lubricating support layer 3a are stably maintained over a long period of time due to the barrier action exhibited by the lubricating functional layer 3b, so that excellent lubricity is not impaired and is maintained over a long period of time.

In the present invention, the lubricating functional layer 3b described above can be easily applied by applying it on the lubricating support layer 3a formed as described above by spray application using a non-Newtonian fluid or a gelling agent-containing fluid. Can be formed.
The lubricating functional layer 3b is usually formed with a thickness of about 0.1 to 100 μm.

The structure 10 of the present invention having the above-described two-layered lubricating film 3 on the surface maintains excellent lubricity with respect to the liquid 20 flowing on the lubricating film 3 over a long period of time, and therefore is filled with various contents. For example, mayonnaise, ketchup, aqueous paste, honey, various sauces, mustard, dressing, jam, chocolate syrup, curry, thick paste food, milky lotion, liquid detergent, shampoo It is suitably applied to containers such as bottles and pouches that accommodate conditioners, rinses and the like.
In particular, excellent lubricity is maintained over a long period of time for detergents, shampoos, conditioners, curry, and thick pasty foods that contain a large amount of surfactants. It is suitable as a container, particularly as a pouch, and particularly suitable as a pouch for edible use or refilling, in which the entire amount is discharged at once.

  In addition, when using as a pouch, after forming the base material 1 of a film form and bag-making this by heat sealing, the lubrication support layer 3a and the lubrication functional layer 3b are spray-sprayed through the opening of a bag. They are formed one after the other, after which they are filled with the contents and finally sealed for opening.

  The invention is illustrated in the following examples.

1. Sliding test The adhesiveness of the contents when the contents were tilted by placing about 2 g of the contents on the surface of the film prepared by the method described later was evaluated by visual observation immediately after dropping the contents and one day later. The case where the contents did not adhere was marked with ◎, and the case where the contents adhered was marked with ×.
The contents used are shown below. In addition, the value measured at 25 degreeC using the tuning fork type vibration type viscometer SV-10 (made by A & D Co., Ltd.) as the viscosity of the content was shown.
Contents used;
Curry (curry shop curry (medium hot), made by House Foods Co., Ltd.)
Conditioner (Lux)
Sauce (preferred sauce, manufactured by Otafuku Sauce)

<Example 1>
A sodium alginate 1 wt% aqueous solution and a calcium chloride 1 wt% aqueous solution were prepared, and the sodium alginate aqueous solution was applied to the surface of the slide glass by dip coating (pulling speed of about 1 cm / SEC). While tilting the slide glass coated with the aqueous sodium alginate solution, the aqueous calcium chloride solution was dropped onto the surface of the aqueous sodium alginate solution. When the excess calcium chloride aqueous solution was removed, a thin aqueous gel film was obtained on the slide glass surface.
On the other hand, a PP film composed of PP / Al / Ny / PET is prepared, and a medium chain fatty acid triglyceride (MCT) (surface tension of 28.8 mN / m, viscosity of 33.8 mPa · s) is bar-coated (# It was applied in 3). Next, the above-mentioned aqueous gel film was placed on the MCT surface, and a lubricating film having a lubricating support layer made of MCT and a lubricating functional layer made of an aqueous gel film on the PP film surface was prepared.
A sliding test was performed using the prepared film. The results are shown in Table 1.

<Example 2>
A PP film coated with MCT by the above-mentioned method is prepared, and instead of the aqueous gel film, a 1 wt% sodium alginate aqueous solution is applied dropwise so as to be about 5 g / m ^2, and a lubricating support layer is formed on the PP film surface. A lubricating film was prepared in which the MCT and the lubricating functional layer were made of a sodium alginate aqueous solution.
A place where the sauce was dropped on the surface of the prepared film and allowed to stand for one day was taken as an immediate section, and a sliding test was conducted. The results are shown in Table 1.

<Comparative Example 1>
A film was prepared in the same manner as in Example 1 except that the lubricating support layer (MCT) was not formed, and a film in which only the lubricating functional layer (aqueous gel film) was formed on the PP film surface was obtained. A sliding test was performed using the prepared film. The results are shown in Table 1.

<Comparative example 2>
A film was prepared in the same manner as in Example 1 except that the lubricating functional layer (aqueous gel film) was not formed, and a film in which only the lubricating support layer (MCT) was formed on the PP film surface was obtained. A sliding test was performed using the prepared film. The results are shown in Table 1.

As can be seen from Table 1, in Examples 1 and 2 using the lubricating film, high slipperiness was exhibited for a long time for any of the contents. In Example 2, since a thin aqueous gel film was formed in the vicinity of the interface of the source of the sodium alginate aqueous solution of the lubricating functional layer, it is presumed that the metal ions of the source were taken into the sodium alginate aqueous solution to form a gel. In any of the contents, it was observed that the contents and the aqueous gel film (lubricating function layer) slide down together.
Further, in Comparative Examples 1 and 2, if either the lubricating functional layer or the lubricating support layer is absent, the lubricity is not exhibited. In Comparative Example 2, although the conditioner had lubricity in the immediately following section, the performance disappeared in the first section.
From the above, it was found that the gel film (lubricating function layer) became a barrier and prevented the disappearance of the lubricating support layer that contributed to the lubricity, so that it was possible to maintain high sliding performance over a long period of time. .

1: Molded body 3: Lubrication film 3a: Lubrication support layer 3b: Lubrication functional layer 10: Structure 20: Fluid in contact with the lubrication film

Claims (11)

In a structure composed of a base material and a lubricating film formed on the surface of the base material,
The lubricating film has a two-layer structure of a lubricating support layer located on the substrate surface side and a lubricating functional layer located on the lubricating support layer,
The structure in which the lubricating functional layer is made of a gelling agent-containing film or a non-Newtonian liquid film.   The structure according to claim 1, wherein the gelling agent-containing film or the non-Newtonian liquid film forming the lubricating functional layer is an aqueous layer, and the lubricating support layer is an oily layer.   The structure according to claim 2, wherein the aqueous layer is formed of water thickened with a water-soluble polymer.   The structure according to claim 3, wherein the water-soluble polymer is at least one selected from the group consisting of xanthan gum, guar gum, gellan gum, pectin, carboxymethylcellulose, gelatin, alginic acid, agar and carrageenan.   The structure according to claim 2, wherein the gelling agent contained in the gelling agent-containing film is an agent that gels by taking in ions contained in a fluid in contact with the lubricating functional layer.   The structure according to claim 5, wherein the gelling agent-containing film is formed of a sodium alginate aqueous solution or a carrageenan aqueous solution.   The structure according to claim 1, wherein the gelling agent-containing film or non-Newtonian liquid film forming the lubricating functional layer is an oily layer, and the lubricating support layer is an aqueous layer.   The structure according to claim 7, wherein the oily layer contains a thickener that is compatible with an oily liquid. The structure according to any one of claims 1 to 8, wherein the substrate has a resin surface.   The structure according to any one of claims 1 to 9, wherein the substrate has a form of a packaging container.   The structure according to claim 10, wherein the packaging container is a pouch.