JP2003220762A - Thin film-shaped object and its use - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin film-shaped object which is excellent in water resistance and transparency and is useful for a coloring layer and a protective layer of a thermal recording medium and an ink receiving layer, protective layer, etc. of an ink-jet recording medium. <P>SOLUTION: The thin film-shaped object is obtained from an aqueous solution which contains acetoacetic ester group-containing polyvinyl alcohol (A) and carbonic zirconyl ammonium (B) and is adjusted below pH 4.0 (20°C). <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin-film material containing acetoacetic acid ester group-containing polyvinyl alcohol (hereinafter abbreviated as AA-PVA) as a main component, and more particularly, it has excellent water resistance and transparency and is heat-sensitive. The present invention relates to a thin film material useful as a recording medium or an inkjet recording medium.

[0002]

2. Description of the Related Art Conventionally, polyvinyl alcohol resins have been used as dispersants, adhesives, sizing agents, films, paper processing agents, etc. PVA is also widely used in applications such as adhesives and paper processing agents. The present situation is that such AA-PVA is usually used in combination with a cross-linking agent and exhibits properties such as water resistance due to the cross-linking reaction.

In particular, it is also used for coating a paper base material such as thermal recording paper to impart water resistance. For example, JP-A-59-106995 discloses AA-PV.
A heat-sensitive recording material having A as a protective layer is described, zirconyl ammonium carbonate is described as a curing agent, and
The applicant of the present invention also disclosed AA PV in JP-A-62-31484.
A heat-sensitive recording processing agent comprising A and a zirconium salt was proposed.

[0004]

However, as disclosed in the above-mentioned publication, the water resistance is not sufficient only by adding zirconyl ammonium carbonate as a curing agent to AA-PVA, and a zirconium salt is used. The resulting film may be colored yellow when dried, and a thin film excellent in water resistance and transparency is desired.

[0005]

The present inventor has made diligent studies in view of such circumstances, and as a result, AA-PVA
The present invention was found to find that a thin film obtained from an aqueous solution containing (A) and zirconyl ammonium carbonate (B) and having a pH adjusted to less than 4.0 (20 ° C.) meets the above object. Has been completed.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The AA-modified PVA (A) used in the present invention is obtained by reacting polyvinyl alcohol with diketene, or by reacting polyvinyl alcohol with acetoacetic ester to transesterify the polyvinyl alcohol to form an acetoacetic acid ester group. Introduced, as such polyvinyl alcohol, generally, a saponified product or a derivative thereof obtained by saponifying a lower alcohol solution of polyvinyl acetate with a saponification catalyst such as an alkali or an acid is used. It is also possible to use a saponified product of a copolymer of a copolymerizable monomer and vinyl acetate.

Examples of such a monomer include ethylene,
Olefin such as propylene, isobutylene, α-octene, α-dodecene, α-octadecene, vinylene carbonates, acrylic acid, methacrylic acid, crotonic acid,
Maleic acid, maleic anhydride, unsaturated acids such as itaconic acid or salts or mono- or dialkyl esters thereof, acrylonitrile, nitriles such as methacrylonitrile, amides such as acrylamide and methacrylamide, ethylene sulfonic acid, allyl sulfonic acid, Olefin sulfonic acids such as methallyl sulfonic acid or salts thereof, alkyl vinyl ethers, N-acrylamidomethyl trimethyl ammonium chloride, allyl trimethyl ammonium chloride, dimethyl diallyl ammonium chloride, dimethyl allyl vinyl ketone, N-vinyl pyrrolidone, vinyl chloride, vinylidene chloride , Polyoxyethylene (meth) allyl ether, polyoxypropylene (meth) allyl ether, etc. Ether, polyoxyethylene (meth) acrylate, polyoxypropylene (meth) acrylate and other polyoxyalkylene (meth) acrylates, polyoxyethylene (meth) acrylamide, polyoxypropylene (meth) acrylamide and other polyoxyalkylene (meth) Acrylamide, polyoxyethylene (1- (meth) acrylamide-1,1-dimethylpropyl) ester, polyoxyethylene vinyl ether, polyoxypropylene vinyl ether, polyoxyethylene allylamine, polyoxypropylene allylamine, polyoxyethylene vinylamine, polyoxy Examples include propylene vinylamine.

The polyvinyl alcohol used as the raw material for the AA-modified PVA (A) is not particularly limited, but the saponification degree is 70 mol% or more (further 75 mol% or more, particularly 8 mol%).
(0 mol% or more) is preferable, and when the saponification degree is less than 70 mol%, the water solubility is poor and a good aqueous solution may not be obtained during film formation, which is not preferable. The average degree of polymerization of the polyvinyl alcohol (JIS K672
6) is also not particularly limited, but is 100 to 5000
(Further 200 to 4500, especially 300 to 400
0) is preferable, and when the average degree of polymerization is less than 100,
In some cases, sufficient water resistance cannot be obtained, and conversely, when it exceeds 5,000, the viscosity of the aqueous solution becomes too high, and it is difficult to obtain a uniform film-like product, which is not preferable.

To obtain AA-PVA (A), a method of reacting polyvinyl alcohol with diketene as described above,
Examples include a method of transesterifying polyvinyl alcohol and acetoacetate ester, a method of copolymerizing vinyl acetate and vinyl acetoacetate, and the like. However, since the production process is simple and high-quality AA-PVA can be obtained. Preferably, it is produced by a method of reacting polyvinyl alcohol (powder) with diketene. As a method of reacting polyvinyl alcohol and diketene, polyvinyl alcohol and gaseous or liquid diketene may be directly reacted, or after organic acid is adsorbed and absorbed in polyvinyl alcohol in advance, it is liquid or under an inert gas atmosphere. A method of spraying and reacting gaseous diketene, or spraying and reacting polyvinyl alcohol with a mixture of an organic acid and liquid diketene is used.

As a reaction apparatus for carrying out the above reaction, an apparatus capable of heating and equipped with a stirrer is sufficient. For example, a kneader, a Henschel mixer, a ribbon blender, other various blenders, and a stirring and drying device can be used.

The content of the acetoacetic acid ester group in the thus obtained AA-PVA (A) is not particularly limited, but it is 0.1-40 mol% (further 0.3-30 mol%, especially 0). 0.5 to 20 mol%) is preferable, and if the content is less than 0.1 mol%, sufficient water resistance may not be obtained, and conversely, if it exceeds 40 mol%, the water solubility may be poor or the aqueous solution may be insufficient. The stability during storage is decreased, which is not preferable.

The thin film material of the present invention comprises the above AA-ized P
It is obtained from an aqueous solution containing VA (A) and zirconyl ammonium carbonate (B) and having a pH adjusted to less than 4.0 (20 ° C.), and its manufacturing method will be specifically described.

AA-PVA (A) contained in an aqueous solution
And the content ratio (A / B) of zirconyl ammonium carbonate (B) is not particularly limited, but AA-modified PV
Content ratio of A (A) and titanium compound (B) (A / B)
However, 100 / 0.1-100 / 30 (further 100 /
0.3-100 / 25, specially 100 / 0.5-100 /
20) (weight ratio) is preferable, and when the content ratio is out of the range, the water resistance of the obtained film tends to decrease, which is not preferable.

AA-modified PV contained in the aqueous solution
The amount of A (A) cannot be generally determined depending on the intended use of the thin film material, the substrate to which it is applied, etc. 5-20% by weight,
In particular, 1 to 15% by weight) is preferable, and if the content is less than 0.1% by weight, a large amount of energy is required to remove water at the time of film formation, and conversely 30% by weight.
If it exceeds, the viscosity of the aqueous solution becomes too high and the handling becomes difficult, which is not preferable.

In the present invention, the AA-modified PV as described above is used.
The pH of the aqueous solution containing A (A) and zirconyl ammonium carbonate (B) is less than 4.0 (20 ° C.) (further 3.8 or less, particularly 3.6 or less, and particularly 3.4 or less) (2
It is important to adjust the temperature to 0 ° C.), and it becomes difficult to achieve the object of the present invention outside this pH range.

Usually, if zirconyl ammonium carbonate (B) is added to an aqueous solution of AA-modified PVA (A), p
When H is about 6 to 9 (20 ° C.), it is necessary to add an acid to lower the pH in order to adjust it to a desired pH. Examples of such an acid include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid and phosphoric acid. And organic acids such as acetic acid, propionic acid, oxalic acid, citric acid, and malonic acid, and hydrochloric acid and acetic acid are preferably used.

The pH-adjusted aqueous solution contains other water-soluble polymers (sodium polyacrylate, polyethylene oxide, polyvinylpyrrolidone, dextrin, chitosan, chitin, methylcellulose, hydroxyethylcellulose) as long as the object of the present invention is not impaired. , (Polyvinyl alcohol other than (A)), plasticizer (glycerin, diglycerin, dipropylene glycol, glycols such as polyethylene glycol, etc.), rust inhibitor, colorant, filler (synthetic silica, colloidal silica, alumina, etc.) It is also possible to add known additives such as surfactants (silicon-based, fluorine-based, polyethylene glycol-based, etc.), preservatives, insect repellents and thickeners.

There is no particular limitation in obtaining (forming a film) a thin film from the pH-adjusted aqueous solution, and a casting method, an extrusion method, a casting method or the like can be adopted, but the casting method is preferable. Method is used. In such casting method,
The thin film material of the present invention can be obtained by a method in which the aqueous solution is cast into a sheet or film on a drum or a belt and dried at 100 to 180 ° C.

The thickness of the thin film finally obtained is from 1 to
100 μm (further 2-50 μm, especially 4-30 μm
m) is preferable, and when the thickness is less than 1 μm, it is difficult to form a film having a uniform thickness, and when it exceeds 100 μm, it is difficult to sufficiently remove water during film formation, which is not preferable.

Thus, the thin film of the present invention having excellent water resistance and transparency can be obtained, and such a thin film can of course be used alone as a film or sheet for various packaging materials. It is also possible to form such a thin film-like material on the material to exert its properties such as water resistance and transparency.

That is, it can be applied to a heat-sensitive recording medium or an ink jet recording medium, and such use will be specifically described. In the thermosensitive recording medium, the thin film material (layer) of the present invention can be applied as a thermosensitive coloring layer, a protective layer, or the like, and can be applied to two or more layers at the same time.

Each of these layers will be described in detail below. In the case of the thermosensitive coloring layer, a color-developing substance and a color developer are further added to the above-mentioned AA-PVA (A) and zirconyl ammonium carbonate (B) to obtain a pH-adjusted aqueous solution,
The aqueous solution may be applied to the base material. AA P at this time
The amount of VA (A) to be added is appropriately 10 to 200% by weight based on the total amount of the color-forming substance and the color developer. The solid content concentration of the aqueous solution is selected from the range of 10 to 40% by weight in consideration of workability.

Examples of the above-mentioned color forming substance include 3,3-
Bis (P-dimethylaminophenyl) -phthalide, 3,
3-bis (P-dimethylaminophenyl) -6-dimethylaminophthalide [crystal violet lactone], 3,3-bis (P-dimethylaminophenyl)-
6-diethylaminophthalide, 3,3-bis (P-dimethylaminophenyl) -6-chlorophthalide, 3-dimethylamino-6-methoxyfluorane, 7-acetamino-3-diethylaminofluorane, 3-diethylamino-5. 7-dimethylfluorane, 3-diethylamino-5,7-dimethylfluorane, 3,6-bis-β
Examples thereof include leuco forms of triphenylmethane dyes such as -methoxyethoxyfluorane and 3,6-bis-β-cyanoethoxyfluorane.

Further, as the color developer, those which react with the above-mentioned color-forming substance to develop color when heated and liquefy or vaporize at room temperature or higher, preferably at 70 ° C. or higher, for example, phenol, P-methylphenol, P-tersia Libutylphenol, P-phenylphenol, α-naphthol, β-naphthol, 4,4′-isopropylidenediphenol [bisphenol A], 4,4′-secondary butylidene diphenol, 4,4′-cyclohexylidenediphenol, 4,4'-isopropylidene bis (2-tert-butylphenol), 4,4'-
(1-methyl-n-hexylidene) diphenol, 4,
4'-isopropylidene dicatechol, 4,4'-pentylidene diphenol, 4,4-isopropylidene bis (2-chlorophenol), phenyl-4-hydroxybenzoate, salicylic acid, 3-phenylsalicylic acid,
5-Methylsalicylic acid, 3,5-di-tert-butylsalicylic acid, 1-oxy-2-naphthoic acid, m-oxybenzoic acid, 4-oxyphthalic acid, gallic acid, etc. are mentioned, but they are color-forming substances and color-developing substances. The agents are not limited to these.

In coating the base material with the aqueous solution, any known method such as a roll coater method, an eardactor method, a blade coater method, a bar coater method, a size press method, and a gate roll method is adopted. The coating amount of the aqueous solution is 0.1 to 20 g / m ² (further 0.5
To 15 g / m ^2, particularly preferably used so that 1 to 10 g / m ²⁾ degree.

Next, the protective layer will be described. The protective layer is a layer formed (coated) on a thermosensitive coloring layer composed of a color-forming substance, a color-developing agent, and a binder (for example, polyvinyl alcohol, methyl cellulose, carboxymethyl cellulose, starches, latexes, etc.). Thus, the thin film layer of the present invention may be formed.

In the coating, the AA-modified PVA (A) and zirconyl ammonium carbonate (B) described above are used.
It is sufficient to use an aqueous solution containing
The coating amount at this time is preferably about 0.5 to 5 g / m ^{2 as} the dry weight of the AA-PVA (A). After coating, the target coating layer is formed by air-drying or mild heat treatment. The coating can be carried out by any means such as a roll coater method, an eardactor method, a blade coater method, a bar coater method, a size press method and a gate roll method.

Further, any auxiliary operation such as mixing various known auxiliaries into the coating layer, or applying the auxiliaries before and after the coating of the coating solution is possible. As such an auxiliary agent, it is optional to use a known additive such as a thermoplastic material such as higher fatty acid amide, a filler such as calcium carbonate or titanium dioxide, a dispersant.

There are no particular restrictions on the base material used in the above-mentioned heat-sensitive recording medium, and paper (manila balls, white balls, paperboard such as liners, printing paper such as general high-quality paper, medium-quality paper, gravure paper, etc.) is used. , Upper / middle / lower grade paper, newsprint paper, release paper, carbon paper, non-carbon paper, glassine paper, etc.) and plastic films (polyester film, nylon film, polyolefin film, polyvinyl chloride film and laminates of these), etc. Can be used.

The heat-sensitive recording medium obtained is as follows.
Substrate / Undercoat layer / Thermal coloring layer / Protective layer, Substrate /
It is possible to have a layer structure such as undercoat layer / thermosensitive coloring layer, substrate / thermosensitive coloring layer / protective layer or substrate / thermosensitive coloring layer.

Next, the ink jet recording medium will be described. When the thin film material (layer) of the present invention is applied to an inkjet recording medium, the thin film layer of the present invention may be formed in or on the surface of the inkjet recording medium. explain.

First, as the base material, for example, polyester, polyamide, polystyrene, polyvinyl chloride, polymethylmethacrylate, cellulose acetate, polycarbonate, polyimide, cellophane, celluloid, and other resin films, sheets, high-quality paper, medium-quality paper, Examples include papers such as (semi) glassine paper, glossy paper, (resin) coated paper, and synthetic paper, and further, films, sheets, etc. of cloth, metal, wood, etc. It is not limited.

In forming the thin film layer of the present invention, an aqueous solution is applied to the surface of the base material in the same manner as in the protective layer of the above-mentioned thermal recording medium to permeate the surface of the base material or the base material. Then, a thin film layer can be formed in the substrate. The coating amount at this time is 0.1 to 20 g / m ² (further 0.5 to 5) in terms of dry weight of the AA-modified PVA (A).
It is preferable that the amount is about 15 g / m ² , particularly about 1 to 10 g / m ² ).

The application to the heat-sensitive recording medium and the ink-jet recording medium has been described above. However, the thin film material of the present invention is not limited to these, but foods, beverages, medicines, pharmaceuticals,
It is also useful for packaging or containers of electrical parts, machine parts, etc., for heating pipes, interior materials for construction such as wallpaper, etc. Furthermore, it is laminated (coated) on PVC leather etc. for furniture and automobiles. It can also be used as an interior material.

[0035]

EXAMPLES The present invention will be described in more detail with reference to examples. In the examples, “%” and “part” are based on weight unless otherwise specified.

Example 1 AA-PVA (A) 100 containing 99.2 mol% of saponification, 1200 in average polymerization degree and 5 mol% of acetoacetic acid ester group.
Parts and 5 parts of zirconyl ammonium carbonate (“Zircosol AC-7” manufactured by Daiichi Rare Element Chemical Co., Ltd.) (B) were dissolved in 1000 parts of water, and hydrochloric acid was added to adjust the pH to 3.0 (20
C.) to obtain an aqueous solution, and the aqueous solution is poured onto a PET film, left standing at 23.degree. C. and 50% RH for 48 hours, and then heat-treated at 70.degree. C. for 5 minutes to give a thickness of 100.
A thin film (film) of the present invention having a thickness of μm was obtained.

In order to examine the water resistance of the obtained film, the film was immersed in hot water at 80 ° C. for 1 hour to measure the elution rate (%) of the film. In calculating the dissolution rate (%), the weight of the film before and after immersion in hot water (g in each case) was calculated, and {(film weight before immersion-film weight after immersion) / film weight before immersion}.
It was calculated by × 100.

Further, the following evaluation was carried out in order to examine the transparency. The film obtained by the above method was left in an atmosphere of 105 ° C. for 1 hour, and the degree of discoloration (yellow) of the film at that time was visually observed and evaluated as follows. ○ ・ ・ ・ Colorless and transparent △ ・ ・ ・ Slightly yellowed × ・ ・ ・ Clearly yellowed

Further, a thermal recording medium was prepared in the following manner and evaluated. First, the following aqueous solution (AC
Liquid) was prepared. [Liquid A] Crystal violet lactone 10 parts 5% aqueous solution of polyvinyl alcohol (saponification degree 98 mol%, average degree of polymerization 1100) 10 parts water 15 parts

[0040] [B liquid]   Bisphenol A 50 parts   5% water of polyvinyl alcohol (saponification degree 98 mol%, average degree of polymerization 1100)   50 parts of solution   75 parts of water

[0041] [C liquid]   AA-PVA (saponification degree 99.2 mol%, average degree of polymerization 1200, acetoacetic acid   100 parts of 10% aqueous solution containing 5 mol% stele group)   Isopropyl tris (N-aminoethyl-aminoethyl) titanate [Ajinomoto   "Plenact KR-44" manufactured by the company] 0.5 part   Kaolin clay part 5

The above liquids A and B were separately pulverized with a sand grinder until the average particle size became about 2μ, and then A
Solution, B solution, 50 parts of calcium carbonate and 15% aqueous solution of polyvinyl alcohol resin same as that used in A solution 2
50 parts were mixed to obtain a color developing solution. Then, the color-developing liquid was applied onto a high-quality paper (base material) having a basis weight of 50 g / m ² so that the coating amount after drying would be 8 g / m ² , and dried to form a color-developing layer. After that, the liquid C was coated on the layer using a Dickson coater so that the coating amount after drying would be 5 g / m ² .
A thermal recording paper was obtained by drying at 60 ° C. The print color density, plasticizer resistance and water resistance of the resulting thermal recording paper were evaluated in the following manner.

(Printing color density) The color was printed by a thermal gradient tester (manufactured by Toyo Seiki Co., Ltd.) under the conditions of 120 ° C., 2 kg / cm ² , and 5 seconds, and the printing color density was measured by a Macbeth densitometer (“RD” manufactured by Macbeth Co. -100R type ", using an amber filter).

(Plasticizer resistance) A thermosensitive recording paper on which a bar code was recorded was sandwiched between soft PVC sheets, a load of 300 g / cm ² was applied, and the mixture was allowed to stand at 40 ° C. for 24 hours, after which it was recorded using a bar code scanner. The reading rate (%) was measured.

(Water resistance) A thermosensitive recording paper on which a bar code was recorded was immersed in tap water at 20 ° C. for 24 hours, and then the attached water was wiped off, and the reading rate (%) was measured using a bar code scanner. did.

Further, an ink jet recording medium was prepared and evaluated according to the following procedure. First, the following aqueous solution (solution D) was prepared. [Liquid D] 10% aqueous solution of AA-PVA (saponification degree 99.2 mol%, average degree of polymerization 1200, acetoacetic acid ester group-containing 5 mol%) 400 parts isopropyl tris (N-aminoethyl-aminoethyl) titanate [Ajinomoto's "Planeact KR-44"] 2 parts Amorphous silica [Tokuyama's "FINESEAL"] 40 parts Polyamine dye fixing agent [Sumitomo Chemical's "Smiraze Resin 1001"] 10 parts

The above-mentioned liquid D was 5,000 with a homogenizer.
The coating liquid was prepared by stirring at rpm for 5 minutes. Then, the coating liquid is applied onto a high-quality paper (base material) having a basis weight of 75 g / m ² so that the coating amount after drying becomes 10 g / m ² , and dried to form an inkjet recording sheet. Got The water resistance of the obtained ink jet recording sheet was evaluated in the following manner.

(Water resistance) After printing on the obtained ink jet recording sheet with an ink jet printer ("PM-770C" manufactured by Seiko Epson Corporation), the recording sheet was left for 5 minutes at 20 ° C and 65% RH, Water droplets were dropped on the printed surface, and the state of the printed portion when the surface was rubbed with a finger was visually observed and evaluated as follows. ○: No breakage or peeling of the printed surface was observed. △: Some peeling was observed, but the image was retained. ×: The printed surface was broken and peeled from the substrate.

Example 2 The same as in Example 1 except that as the AA-PVA (A), an AA-PVA containing 95.0 mol% of saponification, an average degree of polymerization of 1700, and 3 mol% of acetoacetic ester group was used. An aqueous solution was obtained and evaluated in the same manner.

Example 3 In Example 1, zirconyl ammonium carbonate (B)
An aqueous solution was similarly obtained except that the content of was changed to 3 parts, and the same evaluation was performed.

Example 4 An aqueous solution was obtained in the same manner as in Example 1 except that the pH of the aqueous solution was adjusted to 2.5 (20 ° C.) and evaluated in the same manner.

Comparative Example 1 In Example 1, the pH of the aqueous solution was adjusted to 8 without adding hydrochloric acid.
The same evaluation was performed while keeping (20 ° C.).

Comparative Example 2 In Example 1, zirconyl ammonium carbonate (B)
In the same manner as above, except that zirconyl nitrate (“Zircozol ZN” manufactured by Daiichi Rare Element Chemical Co., Ltd.) was used.
An aqueous solution (0 ° C.) was obtained and evaluated in the same manner.

Table 1 shows the evaluation results of Examples and Comparative Examples.

[Table 1] Transparency of film Film for heat-sensitive recording Ink jet recording medium Elution rate (%) Water resistance Example 1 9 ○ 1.37 94 93 ○ 〃 2 7 ○ 1.36 92 94 ○ 〃 3 12 ○ 1.40 93 95 ○ 〃 4 8 ○ 1.35 95 95 ○ Comparative Example 1 82 ○ 1.20 85 67 × 〃 2 8 × 1.38 92 80 △ Note) ~ in the table indicates print color density (), plasticizer resistance (), water resistance ( ) Represents the evaluation item.

[0056]

EFFECT OF THE INVENTION Since the thin film material of the present invention is excellent in water resistance and transparency, it is used for packaging foods, beverages, medicines, pharmaceuticals, electrical parts, machine parts, etc. or containers, and for heating. It is also useful as an interior pipe material for buildings, as an interior material for buildings such as wallpaper, and can be laminated (coated) on PVC leather or the like to be used as an interior material for furniture or automobiles. It is useful as a color forming layer or a protective layer, an ink receiving layer or a protective layer of an inkjet recording medium.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2C056 EA13 FC06                 2H026 AA07 CC05 DD14 DD32 DD48                       DD53 DD55                 2H086 BA01 BA13 BA15 BA35 BA37                       BA41

Claims (5)

[Claims] 1. An aqueous solution containing a polyvinyl alcohol (A) containing an acetoacetic acid ester group and zirconyl ammonium carbonate (B) and having a pH adjusted to less than 4.0 (20 ° C.). Thin film material. 2. A heat-sensitive recording medium comprising the thin film-like material according to claim 1. 3. The heat-sensitive recording medium according to claim 2, wherein the thin film material is either a heat-sensitive coloring layer or a protective layer. 4. An inkjet recording medium comprising the thin film-like material according to claim 1. 5. The ink jet recording medium according to claim 4, wherein the thin film material is either an ink receiving layer or a protective layer.