JPH07188599A - Ink composition and printed material produced by using the same ink composition - Google Patents

Abstract

PURPOSE:To obtain an ink composition containing a dispersant such as an alkylamine, an infrared-emitting fluorescent substance and a binder resin, excel lent in dispersion of the infrared-emitting fluorescent substance, having a high emitting intensity and excellent in emission properties. CONSTITUTION:This ink contains a dispersant composed of an alkylamine (preferably having a 12 to 18C alkyl group) and/or a phosphate (pref erably methacryloyl-based phosphate), an infrared-emitting fluoresceAt substance fpreferably a compound of the formula [A is Al, Bi, B, In, Ga, So, Gd, Ce, Y, Lu or La; (x) is 0 to 0.9 and (y) is 0 to 0.9; 0<x+y<=1)]} and a binder resin in combination.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink composition containing an infrared-emitting phosphor that is excited by infrared light and emits light in the infrared wavelength region, and a printed matter printed or printed with the ink composition. More specifically, the present invention relates to an ink composition having a good dispersibility of an infrared-emitting phosphor and an excellent emission property, and a printed material provided with an infrared emission layer having an excellent emission property, which is printed or printed using this ink composition.

[0002]

2. Description of the Related Art Conventionally, in order to prevent counterfeiting and keep confidential information, an ink composition using an infrared light emitting phosphor that emits light in the infrared wavelength region has been used to be visible to printed materials such as catalogs with the naked eye. It is possible to print an infrared light emitting layer such as a stealth bar code and read the code information with an optical reading device to obtain information such as the characteristics and price of the product or various personal information. It is held (Japanese Patent Publication Sho 61-18)
No. 231, JP-A-53-9600), prepaid card
It has been attempted to print this kind of infrared light emitting layer on a plastic substrate such as a card, an ID card, a magnetic card, or a magnetic layer.

[0005] As the infrared light emitting phosphors for use in the ink composition for printing an infrared light-emitting layer of this type, for example, the general formula _{QD 1-xy Nd x Yb y} P 4 O 12 ( where, Q is At least one element selected from the group consisting of Li, Na, K, Rb, and Cs, and D is S
at least one element selected from the group consisting of c, Y, La, Ce, Gd, Lu, Ga, In,
0.05 ≦ x ≦ 0.999, 0.001 ≦ y ≦ 0.95, and x + y ≦ 1.0. The phosphoric acid-based infrared light emitting phosphor represented by (4) is often used. (Japanese Examined Patent Publication No. 53-40594)

[0004]

However, generally used infrared-emitting phosphors have poor dispersibility and it is difficult to obtain an ink composition having a sufficient emission intensity. In particular, the above-mentioned general formula is used. The phosphoric acid-based infrared-emitting phosphor has a particle size of 7
Since it is as large as μm or more, it is necessary to pulverize when using a UV curable resin as a binder resin, offset printing, printing on an inkjet printer, etc. When pulverized, the crystallinity and composition of the infrared-emitting phosphor can be improved. Is impaired, the dispersibility is remarkably deteriorated, the emission intensity is significantly reduced, and the afterglow is also short.

Further, in order to improve the dispersibility of these infrared-emitting phosphors, surfactants such as alpha-olefin sulfonate, alkylbenzene sulfonate and alkylphenol are generally used as a dispersant. However, there is a problem that sufficient dispersibility cannot be secured even if these are used.

The present invention improves the dispersibility of such a conventional infrared-emitting phosphor and has an ink composition having high emission intensity and excellent emission characteristics, and printing or printing using this ink composition. The object of the present invention is to obtain a printed matter provided with an infrared light emitting layer having excellent light emitting characteristics.

[0007]

The present invention provides at least any one selected from alkylamines and phosphates.
By containing the dispersant of one species together with the infrared-emitting phosphor and the binder resin, the dispersibility of the infrared-emitting phosphor is improved, and an ink composition having high emission intensity and excellent in emission characteristics is obtained. A printed matter having an infrared light emitting layer having excellent light emitting characteristics was obtained using the ink composition.

[0008] In general formula _{A 1-xy Nd x Yb y} PO 4 ( where, A is Al, Bi, B, In, Ga, Sc, G
at least one element selected from d, Ce, Y, Lu, and La, and 0 ≦ x ≦ 0.9, 0 ≦ y ≦ 0.9, 0 <
x + y ≦ 1. By using a fine particle phosphoric acid-based infrared-emitting phosphor having a high emission intensity and a long afterglow, which is represented by the formula (1), and by using it in combination with at least one dispersant selected from alkylamines and phosphates. In addition, when an ultraviolet curable resin is used as a binder resin, offset printing, and an ink composition having excellent luminescent properties, which can be suitably used for printing by an inkjet printer, etc., are obtained, and the luminescent properties are excellent using the ink composition. A printed matter having an infrared emitting layer was obtained.

Further, the general formula A _2-pq Nd _p Yb _q Ca ₅ (MoO ₄ ) ₈ (where A is Al, Bi, B, In, Ga, Sc, G
At least one element selected from d, Ce, Y, Lu, and La, and 0 ≦ p ≦ 2, 0 ≦ q ≦ 2, 0 <p +
q ≦ 2. ) The molybdic acid-based infrared emitting phosphor represented by the formula (1) is used in combination with at least one dispersant selected from alkylamines and phosphates to use an ultraviolet curable resin as a binder resin. In some cases, offset printing, an ink composition having excellent light emitting properties, which can be suitably used for printing with an inkjet printer, etc. is obtained, and a printed matter having an infrared light emitting layer having excellent light emitting properties is obtained using this ink composition. Is.

In the present invention, the alkylamine and the phosphate contained in the ink composition both adhere well to the surface of the infrared-emitting phosphor to improve the affinity with the binder resin, and thus the infrared emission. Disperses the phosphor well in the binder resin.

As the alkylamine, those having 12 to 18 carbon atoms in the alkyl group are preferably used. The alkyl group of the alkylamine may be linear or branched alkyl, and may contain an unsaturated group or an aromatic group. . Specific examples include dodecylamine, stearylamine, myristylamine, and the like, and dodecylamine is more preferably used from the viewpoint of dispersibility.

Further, examples of the phosphate include mono (2-acryloyloxyethyl) acid phosphate.
, Mono (2-methacryloyloxyethyl) acid phosphate, diphenyl-2-methacryloyloxyethyl phosphate and the like are preferably used, and methacryloyl phosphate is more preferably used from the viewpoint of dispersibility.

Either one of these alkylamines and phosphates may be used, but both may be used at the same time. The amount used is less than 0.1% by weight based on the infrared-emitting phosphor. However, the dispersibility of the infrared-emitting phosphor cannot be sufficiently improved, and if it exceeds 5% by weight, it may re-aggregate, or powder may fall off when it is made into a printed matter. It is preferably used within the range of 0.1 to 5% by weight.

Further, as the infrared emitting phosphor and the binder resin used, those conventionally used in general are used, and when a water-soluble resin is used as the binder resin,
A conventionally used phosphoric acid-based infrared emitting phosphor having a particle diameter of 7 μm or more is also suitably used.

However, when an ultraviolet curable resin is used as the binder resin, when printing is performed by an ink jet printer using a water-soluble resin, and when offset printing or the like is performed using a binder resin other than the water-soluble resin. is higher infrared emitting phosphor emission intensity is used a small particle size, for example, the general formula _{A 1-xy Nd x Yb y} PO 4 ( where, A is Al, Bi, B, in, Ga, Sc , G
at least one element selected from d, Ce, Y, Lu, and La, and 0 ≦ x ≦ 0.9, 0 ≦ y ≦ 0.9, 0 <
x + y ≦ 1. ) And phosphate infrared light emitting phosphor represented by the general formula _{A 2-pq Nd p Yb q} Ca 5 (MoO 4) 8 ( where, A is Al, Bi, B, In, Ga, Sc, G
At least one element selected from d, Ce, Y, Lu, and La, and 0 ≦ p ≦ 2, 0 ≦ q ≦ 2, 0 <p +
q ≦ 2. ) The molybdic acid-based infrared light-emitting phosphor represented by (4) is used.

Among the phosphoric acid infrared emitting phosphors of this type, the tetraphosphoric acid infrared emitting phosphor is at least one elemental compound selected from Nd and Yb, and if necessary,
At least 1 selected from Li, Na, K, Rb and Cs
Elemental compounds of at least one species, Sc, Y, La, Ce, Gd,
Tetraphosphate represented by ammonium hydrogen phosphate is added to the raw material powder in which at least one elemental compound selected from Lu, Ga and In is used in combination, and the mixture is fired. Then 50 ° C
It is obtained by treating with the above hydrothermal treatment to remove excess phosphate and other impurities, and the particle size can be variously adjusted to 7 μm or less, and the emission intensity of fine particles with a particle size of 1 μm or less is extremely high. It is possible to obtain an extremely high infrared-emitting phosphor, which can be used as it is in an ink composition without fine pulverization.

Further, the orthophosphoric acid-based infrared light emitting phosphor contains at least one elemental compound selected from Nd and Yb and, if necessary, Al, Bi, B, In, Ga,
The raw material powder in which at least one elemental compound selected from Sc, Gd, Ce, Y, Lu, and La is used in combination with orthophosphoric acid or the general formula M _3-Z H _Z PO ₄ (where M is an alkali or alkaline earth At least one selected from the group of metals, and 0 ≦ z <3) is added, followed by firing, followed by air cooling, and then hydrothermal treatment at 50 ° C. or higher to obtain an excess. It is obtained by removing impurities such as phosphate, and the particle diameter can be variously adjusted to 7 μm or less, and an infrared light-emitting phosphor having a very high emission intensity of fine particles having a particle diameter of 1 μm or less is obtained. As a result, the ink composition can be used as it is without fine pulverization.

The molybdic acid-based infrared emitting phosphor contains at least one elemental compound selected from Nd and Yb,
If necessary, Al, Bi, B, In, Ga, Sc, G
Molybdenum oxide and calcium carbonate are added to a raw material powder in which at least one elemental compound selected from d, Ce, Y, Lu, and La is used in combination, and the mixture is calcined, then air-cooled, and then treated with hydrothermal heat of 50 ° C. or higher. However, it is obtained by removing excess impurities such as molybdenum oxide, and like the phosphoric acid infrared light emitting phosphor, the infrared light emitting phosphor which is granular and has very high emission intensity of fine particles having a particle size of less than 1 μm. Can be obtained and can be used as it is in an ink composition without fine pulverization.

However, this type of phosphoric acid-based infrared light emitting phosphor and molybdic acid-based infrared light emitting phosphor are produced by an ink jet printer when an ultraviolet curable resin is used as a binder resin or when a water-soluble resin is used. When printing,
Further, it is preferably used when performing offset printing or the like using a binder resin other than a water-soluble resin, and when used together with the above-mentioned dispersant, the dispersibility of this type of phosphoric acid infrared-emitting phosphor is improved. An ink composition having high emission intensity can be obtained.

The phosphoric acid-based infrared light emitting phosphor and the molybdic acid-based infrared light emitting phosphor of this kind emit light by the forbidden transition of 4f electrons of Nd and Yb. The reason for this is probably that the base tetraphosphate, orthophosphate, and molybdate have high crystallinity and can contain a large amount of Nd and Yb. Furthermore, a small amount of alkali or alkaline earth metal is included. It is considered that the addition of these compounds further improves the crystallinity and improves the emission intensity.

Here, the tetraphosphate, orthophosphoric acid or the phosphate represented by the above general formula, which is used as a raw material for the phosphoric acid-based infrared emitting phosphor, is used alone or
They may be mixed, and in order to obtain a high emission intensity, among the phosphates represented by the above general formula, those having a large z value are preferably used. Molybdenum oxide is used as a raw material for the molybdic acid-based infrared light emitting phosphor.

The compounds of Nd and Yb elements include oxides, chlorides, carbonates, nitrates of these elements,
Acetate and the like are preferably used, and Al, Bi, B, I
As elemental compounds such as n, Ga, Sc, Gd, Ce, Y, Lu and La, oxides, chlorides, carbonates, nitrates, acetates and the like of these elements are preferably used. Then, the firing puts the raw materials in a crucible, and 400 to 1 in the atmosphere.
The heating is performed at a temperature of 500 ° C., preferably 500 to 1000 ° C. for 0.5 to 6 hours.

When the binder resin used in the ink composition is a water-soluble resin, for example, polyvinyl alcohol
, Polyvinylpyrrolidone, carboxymethylcellulose
Sodium, starch, soda polyacrylate, soda polymethacrylate, etc. are used, and water is used as the solvent. At this time, the infrared-emitting phosphor has a particle size of 0.1
The amount used is preferably in the range of 30 to 90% by weight, and more preferably in the range of 60 to 80% by weight, based on the water-soluble resin.

In the case of a water-soluble resin, particularly when it is used for printing with an ink jet printer, for example, acrylic acid polymer, polyvinyl alcohol, polyvinylpyrrolidone, fatty acid acrylate, glycerin,
Polyethylene glycol and the like are used. Examples of commercially available products of polyethylene glycol include polyethylene glycol # 400, polyethylene glycol # 300, and polyethylene glycol manufactured by Nacalai Tesque, Inc.
Examples include # 600. Commercial products of polyvinyl alcohol include, for example, PVA manufactured by Kuraray Co., Ltd.
203, PVA205, PVA207, PVA105,
PVA110, PA-0510, M manufactured by Shin-Etsu Chemical Co., Ltd.
A-05 etc. are mentioned.

In this case, as the solvent, in addition to water, ethanol, methyl ethyl ketone, or the like is used alone or in a mixture, and in addition, an electric conductivity modifier such as LiNO ₃ or LiCl is also used in combination. .

The infrared light emitting phosphor used at this time has a particle size of 0.1 to 2 μm,
Those having 0.3 to 1 μm are more preferably used. The amount used is a combination ratio of binder resin / infrared emitting phosphor.
Used in the range 0.3 to 2.0, preferably 0.5 to 1.0
Used within the range of. Further, the content ratio of the infrared emitting phosphor is preferably in the range of 3 to 20% by weight, and 5 to 1
More preferably, it is within the range of 0% by weight.

Further, examples of the UV-curable resin include epoxy acrylate, polyester acrylate, polyether acrylate and urethane acrylate.
For example, a polyvalent acryloyl group pendant type UV curable resin such as acrylic acid, acrylic acrylate, and alkyd acrylate is used.

This UV curable resin is used by adding a photoinitiator or an UV absorber, and the viscosity is adjusted by the curing agent for adjusting printing or coating conditions. When using this UV curable resin, the particle size of the infrared emitting phosphor is
0.1 to 1 μm is used, and the amount used is preferably in the range of 10 to 45% by weight, more preferably 25 to 35% by weight, based on the ultraviolet curable resin. .

Particularly when an infrared emitting phosphor having a particle diameter of 0.1 to 1 μm is used, when the ink composition is printed on paper or the like, the fine particle infrared emitting phosphor penetrates into a substrate such as paper. If the UV curable resin is used, the UV curable resin is rapidly cured, and such fine particles of the infrared light emitting phosphor may be removed from the paper. And the like can be effectively suppressed from penetrating into the substrate. Therefore, it is preferable to use the fine particle infrared light emitting phosphor together with the ultraviolet curable resin.

As the binder resin other than the water-soluble resin and the ultraviolet curable resin, polyurethane resin, polyester resin, acrylic resin, polycarbonate resin, polyvinyl butyral resin, polystyrene resin, acrylic silicone are used. Resin, alkyd resin, ethylene-vinyl acetate copolymer, ethyl acrylate resin, epoxy resin,
A phenoxy resin or a modified product thereof is used, and these are used alone or in a mixture.

When these binder resins are used, the infrared emitting phosphor having a particle diameter of 0.1 to 10 μm is used, and the amount of the infrared emitting phosphor to be used is 30 to the binder resin.
It is preferably in the range of 90% by weight, more preferably in the range of 60 to 85% by weight.

As the solvent for dissolving these binder resins, medium- and high-boiling point solvents are preferably used. For example, high-boiling point solvents such as ethylene glycol monobutyl ether and cyclohexanone, and xylene, butyl acetate and acetic acid. A mixture of a medium boiling point solvent such as cellosolve is preferably used.

The ink composition of the present invention is prepared according to a conventional method. For example, at least one kind of dispersant selected from alkylamines and phosphates is mixed with an infrared emitting phosphor, a binder resin and a solvent. It is prepared by mixing and dispersing with the above.

The ink composition thus prepared is then subjected to conventional printing methods such as screen printing, offset printing, gravure printing, letterpress printing and tampon printing.
It is printed directly on paper or a plastic base film such as polyethylene terephthalate film, and also on the magnetic layer, etc., and an infrared light emitting layer such as a stealth bar code which is invisible to the naked eye is printed. Printed materials such as catalogs, prepaid cards, ID cards, magnetic cards, etc. can be obtained.

The thickness of the infrared emitting layer thus printed varies depending on the printing method and is preferably 1 to 20 μm when screen printing is used, and 2 to 8 μm.
More preferably, the thickness is μm.

In any case of offset printing, gravure printing and relief printing, the thickness is preferably 0.2 to 4 μm, more preferably 0.5 to 2 μm. Furthermore, when using tampon printing, 0.2-
The thickness is preferably 10 μm, more preferably 0.5 to 5 μm.

In addition, this ink composition is also suitably used for printing with an ink jet printer and the like, and infrared emission excellent in light emission characteristics is carried out on paper or a plastic base film such as polyethylene terephthalate film. The layers are printed.

In the ink composition, various pigments and dyes other than carbon which absorb infrared rays, such as dyes, are used.
Kid C (red organic pigment), phthalocyanine blue (blue organic pigment) and the like may be added.

[0039]

EXAMPLES Next, examples of the present invention will be described. Example 1 Lithium dihydrogen phosphate (LiH ₂ PO ₄ ) 260.0 parts by weight Neodymium oxide (Nd ₂ O ₃ ) 9.4 〃 Ytterbium oxide (Yb ₂ O ₃ ) 10.9 〃 Yttrium oxide (Y ₂ O ₃ ) 50.2 〃 The above composition Was thoroughly mixed and filled in a crucible with a lid made of alumina, then placed in an electric furnace, heated from room temperature to 750 ° C. at a constant heating rate over 2 hours, and then fired at 750 ° C. for 2 hours.

Immediately after firing, take out from the electric furnace,
It was left to cool in the air. Then, boiling water was put into the crucible at 100 ° C., the infrared light emitting phosphor was taken out from the crucible, washed with 1N nitric acid, washed with water and dried to obtain an infrared light emitting phosphor. The particle size of the obtained infrared-emitting phosphor is
At 0.5 μm, the composition was Nd _0.1 Yb _0.1 Y _0.8 PO ₄ .

Then, using the obtained infrared-emitting phosphor, an infrared-emitting phosphor (Nd _0.1 Yb _0.1 Y _0.8 PO ₄ , particle size 48.4 parts by weight 0.5 μm) VAGH (manufactured by UCC, USA; vinyl chloride- Vinyl acetate-bi 11.0 〃 Nyl alcohol copolymer) Cyclohexanone 38.5 〃 Butyl cellosolve 4.4 〃 Dodecylamine 1.0 〃 Composition was mixed and dispersed in sand mill for 1 hour, and further, Coronet L (Nippon Polyurethane Industry Co., Ltd .; trifunctional) Low molecular weight isocyanate compound) of 1.1 parts by weight,
An ink composition was prepared by mixing and dispersing for a period of time. Then, this ink composition was printed on paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 2 Using the infrared emitting phosphor obtained in Example 1, infrared emitting phosphor (Nd _0.1 Yb _0.1 Y _0.8 PO ₄ , particle size 37.5 parts by weight 0.5 μm) Nopcoma-4510 (San Nopco Company: Aliphatic 5-functional acrylic 18.0 〃 Relate, UV curable resin Photoma-4149SN (Henkel company; Aliphatic trifunctional acrylic 10.6 〃 Cleat, UV curable resin) Photoma-6008 (Henkel company) Polyurethane type 3 44.4 〃 Acrylate, UV curable resin) Irgacure 907 (Ciba-Geigy Co .; photoinitiator) 2.1 〃 Darocur 1173 (EM Chemical Co .; photoinitiator) 3.1 〃 Dodecylamine 0.5 〃 An ink composition was prepared by kneading a composition of diphenyl-2-methacryloyloxyethyl phosphate 0.5 〃 with 3 rolls for 1 hour. Then, this ink composition was printed on paper by offset printing. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Example 3 An infrared light emitting phosphor was obtained in the same manner as in Example 1 except that neodymium oxide was omitted in the production of the infrared light emitting phosphor in Example 1. The particle size of the obtained infrared-emitting phosphor is
At 0.6 μm, the composition was Yb _0.11 Y _0.89 PO ₄ .

Then, in the preparation of the ink composition in Example 1, the infrared-emitting phosphor (N
An ink composition was prepared in the same manner as in Example 1 except that the same amount of the obtained infrared light-emitting phosphor (Yb _0.11 Y _0.89 PO ₄ ) was used instead of d _0.1 Yb _0.1 Y _0.8 PO ₄ ). , Printed by screen printing on paper. At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 4 An infrared light emitting phosphor was obtained in the same manner as in Example 1 except that yttrium oxide was omitted from the production of the infrared light emitting phosphor in Example 1. The obtained infrared light emitting phosphor had a particle size of 0.6 μm and a composition of Nd _0.5 Yb _0.5 PO ₄ .

Then, in the preparation of the ink composition in Example 1, the infrared-emitting phosphor (N
An ink composition was prepared in the same manner as in Example 1 except that the obtained infrared light emitting phosphor (Nd _0.5 Yb _0.5 PO ₄ ) was used in the same amount instead of d _0.1 Yb _0.1 Y _0.8 PO _4. ,
It was printed on the paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 5 In the preparation of the ink composition in Example 2, the infrared-emitting phosphor (Nd _0.1 Yb _0.1 Y _0.8 ) used in Example 2 was prepared.
An ink composition was prepared in the same manner as in Example 2 except that the same amount of the infrared light emitting phosphor (Yb _0.11 Y _0.89 PO ₄ ) obtained in Example 3 was used instead of PO ₄ ). Printed by offset printing. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Example 6 In the preparation of the ink composition in Example 2, the infrared emitting phosphor (Nd _0.1 Yb _0.1 Y _0.8 ) used in Example 2 was prepared.
An ink composition was prepared in the same manner as in Example 2 except that the same amount of the infrared light emitting phosphor (Nd _0.5 Yb _0.5 PO ₄ ) obtained in Example 4 was used instead of PO ₄ ). And printed on the paper by offset printing. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Example 7 Ammonium dihydrogen phosphate [(NH ₄ ) H ₂ PO ₄ ] 162.0 parts by weight Lithium carbonate (LiCO ₃ ) 39.6 〃 Neodymium oxide (Nd ₂ O ₃ ) 13.0 〃 The above composition was thoroughly mixed. After filling a crucible with a lid made of alumina, it was placed in an electric furnace and heated from room temperature to 650 ° C. at a constant heating rate for 2 hours, and then at 650 ° C.
It was baked for 0.5 hours.

Immediately after the firing, take out from the electric furnace,
It was left to cool in the air. Then, boiling water was put into the crucible at 100 ° C., the infrared light emitting phosphor was taken out from the crucible, washed with 1N nitric acid, washed with water and dried to obtain an infrared light emitting phosphor. The particle size of the obtained infrared-emitting phosphor is
At 2.0 μm, the composition was LiNdP ₄ O ₁₂ .

Then, using the obtained infrared light emitting phosphor, infrared light emitting phosphor (LiNdP ₄ O ₁₂ , particle size 2.0 μm) 42.1 parts by weight Kuraray PVA 205 (Kuraray Co .; vinyl alcohol resin) 10.5 〃 An ink composition was prepared by mixing and dispersing a composition of water 52.7〃dodecylamine 0.5〃 in a ball mill for 96 hours. Then, this ink composition was printed on paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 8 Using the infrared-emitting phosphor obtained in Example 1, infrared-emitting phosphor (Nd _0.1 Yb _0.1 Y _0.8 PO ₄ , particle size 10.0 parts by weight 0.5 μm) polyethylene glycol ( An ink composition was prepared by mixing and dispersing a composition of polyethyl 12.0 〃 ren glycol) water 65.0 〃 dodecylamine 0.5 〃 LiNO ₃ 0.5 〃 ethanol 20.0 〃 by a sand mill manufactured by Nacalai Tesque. Then, this ink composition was used to print on paper with an inkjet printer.

Example 9 In the same manner as in Example 8, except that the same amount of polyvinyl alcohol (Kuraray Co .; PVA203) was used in place of polyethylene glycol in the preparation of the ink composition in Example 8. An ink composition was prepared and printed on paper with an inkjet printer.

Example 10 Ammonium dihydrogen phosphate [(NH ₄ ) H ₂ PO ₄ ] 75.7 parts by weight Neodymium oxide (Nd ₂ O ₃ ) 16.2 〃 Ytterbium oxide (Yb ₂ O ₃ ) 2.2 〃 Lithium carbonate (Li ₂ CO) ₃ ) 5.9 〃 The above composition was thoroughly mixed and filled in a crucible with a lid made of alumina, then placed in an electric furnace and heated from room temperature to 650 ° C at a constant heating rate over 2 hours, and then 650 Calcination was performed for 1 hour.

Immediately after firing, take out from the electric furnace,
It was left to cool in the air. Then, boiling water was put into the crucible at 100 ° C., the infrared light emitting phosphor was taken out from the crucible, washed with 1N nitric acid, washed with water and dried to obtain an infrared light emitting phosphor. The particle size of the obtained infrared-emitting phosphor is
At 2.0 μm, the composition was LiNd _0.9 Yb _0.1 P ₄ O ₁₂ .

Then, in the preparation of the ink composition in Example 7, the infrared-emitting phosphor (L
Same as Example 7 except that the same amount of the obtained infrared light emitting phosphor (LiNd _0.9 Yb _0.1 P ₄ O ₁₂ , particle size 2.0 μm) was used instead of iNdP ₄ O ₁₂ , particle size 2.0 μm). The ink composition was prepared and printed on a paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 11 An ink composition was prepared in the same manner as in Example 1 except that the amount of dodecylamine used was changed from 1.0 part by weight to 0.05 part by weight in the preparation of the ink composition in Example 1. It was printed on the paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 12 An ink composition was prepared in the same manner as in Example 1 except that the amount of dodecylamine used in Example 1 was changed from 1.0 part by weight to 2.4 parts by weight. It was printed on the paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 13 An ink composition was prepared in the same manner as in Example 2 except that dodecylamine was omitted from the preparation of the ink composition in Example 2, and printing was performed on paper by offset printing. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Example 14 An ink composition was prepared in the same manner as in Example 1 except that the same amount of stearylamine was used instead of dodecylamine in the preparation of the ink composition in Example 1, and the ink composition was screened on paper. It was printed by printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 15 In the preparation of the ink composition in Example 2, the same amount of mono (2-acryloyloxyethyl) acid phosphate was used instead of diphenyl-2-methacryloyloxyethyl phosphate. Was prepared in the same manner as in Example 2 and printed on paper by offset printing. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Example 16 Molybdenum oxide (MoO ₃ ) 384.0 parts by weight Neodymium oxide (Nd ₂ O ₃ ) 101.0 〃 Ytterbium oxide (Yb ₂ O ₃ ) 13.1 〃 Calcium carbonate (CaCO ₃ ) 166.7 〃 The above composition was thoroughly mixed. Then, the crucible with a lid made of alumina was filled, then placed in an electric furnace, heated from room temperature to 750 ° C. at a constant heating rate over 2 hours, and then fired at 750 ° C. for 2 hours.

Immediately after firing, the product was taken out of the electric furnace and
It was left to cool in the air. Then, hot water of 100 ° C. was put into the crucible and boiled, the infrared light emitting phosphor was taken out from the crucible, washed with water, and dried to obtain an infrared light emitting phosphor. The obtained infrared light emitting phosphor has a particle size of 0.6 μm and a composition of Nd.
_{It was 1.8} Yb _0.2 Ca ₅ (MoO ₄ ) ₈ .

Next, in the preparation of the ink composition in Example 1, the infrared-emitting phosphor (N
d _0.1 Yb _0.1 Y _0.8 PO ₄ ) instead of the obtained infrared-emitting phosphor (Nd _1.8 Yb _0.2 Ca ₅ (MoO ₄ ) ₈ ).
An ink composition was prepared in the same manner as in Example 1 except that the same amount was used, and the composition was printed on a paper by screen printing.
At this time, the thickness of the infrared light emitting layer was 5 μm.

Example 17 In the preparation of the ink composition in Example 2, the infrared light emitting phosphor (Nd _0.1 Yb _0.1 Y _0.8 ) used in Example 2 was prepared.
The ink composition was prepared in the same manner as in Example 2 except that the same amount of the infrared light emitting phosphor (Nd _1.8 Yb _0.2 Ca ₅ (MoO ₄ ) ₈ ) obtained in Example 16 was used instead of PO ₄ ). Was prepared and printed by offset printing on paper. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Example 18 In the preparation of the ink composition of Example 8, the infrared-emitting phosphor (Nd _0.1 Yb _0.1 Y _0.8 ) used in Example 8 was used.
Ink composition in the same manner as in Example 8 except that the same amount of the infrared light emitting phosphor (Nd _1.8 Yb _0.2 Ca ₅ (MoO ₄ ) ₈ ) obtained in Example 16 was used instead of PO ₄ ). Was prepared and printed on a paper by an inkjet printer.

Comparative Example 1 An ink composition was prepared in the same manner as in Example 1 except that dodecylamine was omitted from the preparation of the ink composition in Example 1, and printed on paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Comparative Example 2 An ink composition was prepared in the same manner as in Example 2 except that dodecylamine and diphenyl-2-methacryloyloxyethyl phosphate were omitted from the preparation of the ink composition in Example 2. , Printed by offset printing on paper. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Comparative Example 3 An ink composition was prepared in the same manner as in Example 3 except that the dodecylamine was omitted from the preparation of the ink composition in Example 3, and printed on paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Comparative Example 4 An ink composition was prepared in the same manner as in Example 4 except that the dodecylamine was omitted from the preparation of the ink composition in Example 4, and printed on paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Comparative Example 5 An ink composition was prepared in the same manner as in Example 5 except that dodecylamine and diphenyl-2-methacryloyloxyethyl phosphate were omitted from the preparation of the ink composition in Example 5. , Printed by offset printing on paper. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Comparative Example 6 An ink composition was prepared in the same manner as in Example 6 except that dodecylamine and diphenyl-2-methacryloyloxyethyl phosphate were omitted from the preparation of the ink composition in Example 6. , Printed by offset printing on paper. At this time, the thickness of the infrared light emitting layer was 1.0 μm.

Comparative Example 7 An ink composition was prepared in the same manner as in Example 7 except that the dodecylamine was omitted from the preparation of the ink composition in Example 7, and printed on paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Comparative Example 8 An ink composition was prepared in the same manner as in Example 8 except that dodecylamine was omitted from the preparation of the ink composition in Example 8, and the ink composition was used. Printed on paper.

Comparative Example 9 An ink composition was prepared in the same manner as in Example 10 except that dodecylamine was omitted from the preparation of the ink composition in Example 10, and the composition was printed on a paper by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Comparative Example 10 An ink composition was prepared in the same manner as in Example 16 except that dodecylamine was omitted from the preparation of the ink composition in Example 16, and the composition was printed on a screen by screen printing. At this time, the thickness of the infrared light emitting layer was 5 μm.

Comparative Example 11 An ink composition was prepared in the same manner as in Example 17, except that dodecylamine and diphenyl-2-methacryloyloxyethyl phosphate were omitted from the preparation of the ink composition in Example 17. , Printed by offset printing on paper. The thickness of the infrared emitting layer at this time is 1.0μ
It was m.

Comparative Example 12 An ink composition was prepared in the same manner as in Example 18 except that dodecylamine was omitted from the preparation of the ink composition in Example 18, and an ink jet printer
Printed by.

Comparative Example 13 An ink composition was prepared in the same manner as in Example 1 except that the same amount of sodium dodecylbenzenesulfonate was used instead of dodecylamine in the preparation of the ink composition of Example 1. , Printed by screen printing on paper. At this time, the thickness of the infrared light emitting layer was 5 μm.

The emission intensity of the infrared emitting layer on the paper printed or printed with the ink composition obtained in each of the examples and comparative examples was examined. When the infrared emission phosphor containing Nb and Yb is used, this emission intensity is measured by exciting with a light source with a wavelength of 810 nm and receiving the emitted light with a silicon photodetector with a peak sensitivity of 980 nm. did. An optical filter (Imp) was used on the front surface of the light receiving element to prevent the influence of the reflected light of the excitation light.

When an infrared-emitting phosphor containing Yb is used, it is excited by a light source with a wavelength of 950 nm and turned off.
After μs, the emission intensity was measured by receiving the afterglow with a silicon photodetector having a peak sensitivity of 980 nm.

When the infrared emitting phosphor containing Nd is used, the emission intensity is shown by setting the value of Example 1 and Example 16 as 100, and the infrared emitting phosphor containing Yb and Y is used. In this case, the value in Example 3 was displayed as 100.
Furthermore, when printing with an inkjet printer,
The value of Example 8 was expressed as 100. Table 1 below shows the results.

[0083]

[0084]

As is apparent from Table 1 above, Example 1
The infrared emission layers printed or printed with the ink compositions obtained in Nos. 18 to 18 are all higher in emission intensity than the infrared emission layers printed or printed with the ink compositions obtained in Comparative Examples 1 to 13. From this, the ink composition obtained by the present invention, and the printed matter printed or printed using this ink composition, have good dispersibility of the infrared-emitting phosphor, high emission intensity and excellent emission characteristics. It turns out to be excellent.

Claims (26)

[Claims] 1. An ink composition comprising at least one dispersant selected from alkylamines and phosphates together with an infrared-emitting phosphor and a binder resin. 2. The alkylamine has 12 to 1 carbon atoms.
An alkylamine having 8 alkyl groups.
Ink composition described 3. The ink composition according to claim 1, wherein the phosphate is methacryloyl phosphate. Wherein infrared light emitting phosphor has the general formula _{A 1-xy Nd x Yb y} PO 4 ( where, A is Al, Bi, B, In, Ga, Sc, G
at least one element selected from d, Ce, Y, Lu, and La, and 0 ≦ x ≦ 0.9, 0 ≦ y ≦ 0.9, 0 <
x + y ≦ 1. The ink composition according to claim 1, which is an infrared-emitting phosphor represented by 5. The infrared-emitting phosphor comprises at least one elemental compound selected from Nd and Yb and orthophosphoric acid or the general formula M _3-Z H _Z PO ₄ (where M is an alkali or alkaline earth metal). At least one selected from the formulas, and 0 ≦ z <3) is added, and the mixture is baked, air-cooled, and then treated by hydrothermal treatment at 50 ° C. or higher. The ink composition according to claim 1, which is the infrared-emitting phosphor according to claim 4. 6. The infrared-emitting phosphor comprises at least one elemental compound selected from Nd and Yb, Al, Bi,
A raw material powder in which at least one elemental compound selected from B, In, Ga, Sc, Gd, Ce, Y, Lu, and La is used in combination with orthophosphoric acid or the general formula M _3-Z H _Z
After adding a phosphate represented by PO ₄ (wherein M is at least one selected from alkali or alkaline earth metals and 0 ≦ z <3), followed by firing and then air cooling, 5. Obtained by treating with hydrothermal heat of 50 ° C. or higher.
The ink composition according to claim 1, which is the infrared-emitting phosphor according to claim 1. 7. The infrared-emitting phosphor has a general formula of A _2-pq Nd _p Yb _q Ca ₅ (MoO ₄ ) ₈ (where A is Al, Bi, B, In, Ga, Sc, G).
At least one element selected from d, Ce, Y, Lu, and La, and 0 ≦ p ≦ 2, 0 ≦ q ≦ 2, 0 <p +
q ≦ 2. The ink composition according to claim 1, which is an infrared-emitting phosphor represented by 8. An infrared-emitting phosphor is obtained by adding molybdenum oxide and calcium carbonate to at least one elemental compound selected from Nd and Yb, followed by firing, then air cooling, and then treating with hydrothermal heat of 50 ° C. or higher. The ink composition according to claim 1, which is the infrared-emitting phosphor according to claim 7, obtained by 9. The infrared-emitting phosphor comprises at least one elemental compound selected from Nd and Yb, Al, Bi,
After molybdenum oxide and calcium carbonate are added to the raw material powder that is used in combination with at least one elemental compound selected from B, In, Ga, Sc, Gd, Ce, Y, Lu, and La, and the mixture is air-cooled The ink composition according to claim 1, which is the infrared-emitting phosphor according to claim 7, which is obtained by treating with water heat of 50 ° C or higher. 10. The infrared light-emitting phosphor is an infrared light-emitting phosphor having a particle diameter of 0.1 μm or more and 2 μm or less, claim 1, claim 4, claim 5, claim 6, claim 7, claim 8. Alternatively, the ink composition according to claim 9. 11. The ink composition according to claim 1, wherein the binder resin is an ultraviolet curable resin. 12. The ink composition according to claim 1, wherein the binder resin is a water-soluble resin. 13. The ink composition according to claim 1, further comprising a conduction aid in the ink composition. 14. An ink composition containing at least one dispersant selected from alkylamines and phosphates together with an infrared-emitting phosphor and a binder resin is printed or printed on a base film. Printed matter characterized by forming an infrared light emitting layer 15. The printed matter according to claim 14, wherein the alkylamine is an alkylamine having an alkyl group having 12 to 18 carbon atoms. 16. The printed matter according to claim 14, wherein the phosphate is methacryloyl-based phosphate. 17. The infrared-emitting phosphor has the general formula _{A 1-xy Nd x Yb y} PO 4 ( where, A is Al, Bi, B, In, Ga, Sc, G
at least one element selected from d, Ce, Y, Lu, and La, and 0 ≦ x ≦ 0.9, 0 ≦ y ≦ 0.9, 0 <
x + y ≦ 1. 15. The printed matter according to claim 14, which is an infrared-emitting phosphor represented by 18. The infrared-emitting phosphor is characterized in that at least one elemental compound selected from Nd and Yb is added with orthophosphoric acid or the general formula M _3-Z H _Z PO ₄ (where M is an alkali or alkaline earth metal). At least one selected from the formulas, and 0 ≦ z <3) is added, and the mixture is baked, air-cooled, and then treated by hydrothermal treatment at 50 ° C. or higher. The printed matter according to claim 14, which is the infrared-emitting phosphor according to claim 17. 19. The infrared-emitting phosphor comprises at least one elemental compound selected from Nd and Yb, and Al and B.
i, B, In, Ga, Sc, Gd, Ce, Y, Lu, L
orthophosphoric acid or general formula M _3-Z
H _Z PO ₄ (where M is at least one selected from alkali or alkaline earth metals, and 0 ≦ z <3
Is. The printed product according to claim 14, which is the infrared-emitting phosphor obtained by adding a phosphate represented by the formula (4), firing the mixture, cooling it with air, and then treating it with hydrothermal heat of 50 ° C or higher. 20. The infrared-emitting phosphor has the general formula A _2-pq Nd _p Yb _q Ca ₅ (MoO ₄ ) ₈ (where A is Al, Bi, B, In, Ga, Sc, G).
At least one element selected from d, Ce, Y, Lu, and La, and 0 ≦ p ≦ 2, 0 ≦ q ≦ 2, 0 <p +
q ≦ 2. 15. The printed matter according to claim 14, which is an infrared-emitting phosphor represented by 21. An infrared-emitting phosphor is prepared by adding molybdenum oxide and calcium carbonate to at least one elemental compound selected from Nd and Yb, followed by firing, then air cooling, and then treating with hydrothermal heat of 50 ° C. or higher. Claim 2 obtained by
The printed matter according to claim 14, which is the infrared-emitting phosphor according to 0. 22. The infrared-emitting phosphor comprises at least one elemental compound selected from Nd and Yb, and Al and B.
i, B, In, Ga, Sc, Gd, Ce, Y, Lu, L
21. Obtained by adding molybdenum oxide and calcium carbonate to a raw material powder that is used in combination with at least one or more elemental compounds selected from a, calcined, air-cooled, and then treated with hydrothermal heat of 50 ° C. or higher. The printed matter according to claim 14, which is the infrared-emitting phosphor according to claim 15. 23. The infrared light-emitting phosphor is an infrared light-emitting phosphor having a particle diameter of 0.1 μm or more and 2 μm or less, claim 14, claim 17, claim 18, claim 19, claim 20, claim 21. Alternatively, the printed matter according to claim 22. 24. The printed matter according to claim 14, wherein the binder resin is an ultraviolet curable resin. 25. The printed matter according to claim 14, wherein the binder resin is a water-soluble resin. 26. The printed matter according to claim 14, wherein the ink composition further contains a conduction aid.