阅读说明：本技术 制备金属纳米颗粒层的方法及其在装饰或安全元件中的用途 (Method for producing a metal nanoparticle layer and use thereof in decorative or security elements ) 是由 N·A·格里戈连科 M·里歇特 于 2018-05-07 设计创作，主要内容包括：本发明涉及一种制备包含银纳米颗粒的薄层的方法，所述纳米颗粒是作为涂覆或印刷方法的一部分直接在基材上产生的。所述层在透射和反射时显示出不同的颜色。所述层不显示出金属层的典型导电性，因为颗粒基本上是未烧结的离散颗粒。本发明进一步涉及装饰和安全元件。当将所述层施加至安全元件(例如全息图)上时，所获得的产品还在反射和透射时显示出不同的颜色，显示出极其明亮的光学可变图像(OVD图像)以及高纯度和对比度。取决于层厚，呈现或高或低强度的金属外观。(The present invention relates to a method for preparing a thin layer comprising silver nanoparticles, which nanoparticles are produced directly on a substrate as part of a coating or printing process. The layers exhibit different colors in transmission and reflection. The layer does not exhibit the typical conductivity of a metal layer because the particles are essentially discrete particles that are not sintered. The invention further relates to a decorative and security element. When the layer is applied to a security element, such as a hologram, the product obtained also shows different colours in reflection and transmission, shows an extremely bright optically variable image (OVD image) and high purity and contrast. Depending on the layer thickness, a metallic appearance of either high or low strength is present.)

1. A method of forming a layer comprising silver nanoparticles on a substrate, comprising the steps of:

A) optionally forming an Optically Variable Device (OVD) on discrete portions of the substrate;

B) applying a composition onto at least a part of the substrate, and/or optionally onto at least a part of the OVD obtained in step a), wherein the composition comprises:

b1) a precursor of a silver metal,

b2) the acid is added to the mixture of the acid,

b3) optionally a solvent, and optionally a solvent, to form a mixture,

b4) optionally substituted polyhydric phenols, and

b5) optionally a polymeric binder, optionally in the form of a binder,

C) exposing the coating obtained in step B) to heating and/or irradiating the coating with electromagnetic radiation, thereby forming a highly reflective layer comprising silver nanoparticles.

2. The method according to claim 1, wherein the silver metal precursor is selected from the formula R¹¹A compound of C (═ O) OAg, wherein R¹¹Is C₁-C₈Alkyl, in which part of the hydrogen atoms may be replaced by F and/or Cl, such as silver trifluoroacetate, silver difluoroacetate, silver chlorodifluoroacetate, silver 3,3, 3-trifluoropropionate, silver pentafluoropropionate, silver heptafluorobutyrate, silver heptafluoroisobutyrate, silver perfluorovalerate, silver perfluorohexanoate, silver perfluoroheptanoate, silver perfluorooctanoate, silver acetate, silver propionate, silver butyrate, silver isobutyrate, silver valerate, silver hexanoate, silver ethylbutyrate, silver monochloroacetate, silver dichloroacetate, silver trichloroacetate, silver pivalate; formula R¹²C(＝O)CH＝C(-OAg)-R¹³Wherein R is¹²And R¹³Independently of one another are C₁-C₈Alkyl in which part of the hydrogen atoms may be replaced by F, or optionally substituted phenyl, such as silver acetylacetonate, silver 1,1, 1-trifluoroacetylacetonate, silver 1,1,1,5,5,5, 5-hexafluoroacetylacetonate, silver 1-phenyl-4, 4, 4-trifluorobutanedione, silver 1- (4-methoxyphenyl) -4,4, 4-trifluorobutanedione; formula R¹⁴OC(＝O)CH＝C(-OAg)-R¹⁵Wherein R is¹⁴Is C₁-C₈Alkyl radical, R¹⁵Is C₁-C₈Alkyl groups in which part of the hydrogen atoms may be replaced by F, for example silver complexes of ethyl acetoacetate, silver complexes of 3-oxo-4, 4, 4-trifluorobutanoic acid and mixtures thereof.

3. The process according to claim 1 or 2, wherein the acid is selected from monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, difluoroacetic acid, trifluoroacetic acid, pentafluoropropionic acid, heptafluorobutyric acid, perfluorovaleric acid, perfluorohexanoic acid, perfluoroheptanoic acid, perfluorooctanoic acid, and 1,1,1,5,5, 5-hexafluoroacetylacetone and mixtures thereof.

4. A process according to any one of claims 1 to 3, wherein the solvent is selected from the group consisting of water, alcohols (e.g. methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, tert-amyl alcohol), cyclic or acyclic ethers (e.g. diethyl ether, tetrahydrofuran and 2-methyltetrahydrofuran), ketones (e.g. acetone, 2-butanone, 3-pentanone), ether-alcohols (e.g. 2-methoxyethanol, 1-methoxy-2-propanol, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether and diethylene glycol monobutyl ether), polar aprotic solvents (e.g. acetonitrile, dimethylformamide and dimethyl sulfoxide) and mixtures thereof.

5. A method according to any one of claims 1 to 4 wherein the polyhydric phenol is tannic acid or a compound of formula (la)

R¹may be the same or different at each occurrence and is a hydrogen atom, a halogen atom, C₁-C₁₈Alkyl radical, C₁-C₁₈Alkoxy or-C (═ O) -R³The group of (a) or (b),

R³is a hydrogen atom, C₁-C₁₈Alkyl, unsubstituted or substituted amino or C₁-C₁₈Alkoxy radical, and

n is a number from 1 to 4.

m is a number from 2 to 4, and

the sum of m and n is 6.

6. The process of claim 5 wherein said polyhydric phenol is of the formula

7. The method according to any one of claims 1-6, wherein the binder comprises nitrocellulose, ethylcellulose, Cellulose Acetate Propionate (CAP), Cellulose Acetate Butyrate (CAB), hydroxyethyl cellulose, hydroxypropyl cellulose, alcohol-soluble propionate (ASP), vinyl chloride, vinyl acetate copolymers, vinyl acetate, vinyl, acrylic, polyurethane, polyamide, rosin ester, hydrocarbon, aldehyde, ketone, urethane, polyethylene terephthalate, terpene phenol, polyolefin, silicone, cellulose, polyamide, polyester, rosin ester resin, shellac, and mixtures thereof.

8. The method according to any one of claims 1 to 7, wherein step A) comprises:

a1) applying a curable composition to at least a portion of a substrate;

a2) contacting at least a portion of the curable composition with an OVD forming apparatus; and

a3) curing the curable composition treated in step a2) by means of an OVD forming apparatus.

9. A security or decorative element comprising a substrate which may comprise indicia or other visible features in or on its surface and comprising a silver layer obtainable by the process according to any one of claims 1 to 8 on at least a portion of its surface.

10. The security or decorative element according to claim 9, wherein the silver layer is coated with a protective layer.

11. Use of an element according to claim 9 or 10 for preventing the counterfeiting or duplication of documents of value, rights, identities, security labels or branded goods.

12. A coating or printing ink composition comprising:

b1) a precursor of a silver metal,

b2) the acid is added to the mixture of the acid,

b3) optionally a solvent, and optionally a solvent, to form a mixture,

b4) a polyhydric phenol, and

b5) optionally a polymeric binder.

13. The coating or printing ink composition of claim 12, wherein:

silver metal precursor b1) is selected from the formula R¹¹A compound of C (═ O) OAg, wherein R¹¹Is C₁-C₈Alkyl, in which part of the hydrogen atoms may be replaced by F and/or Cl, such as silver trifluoroacetate, silver difluoroacetate, silver chlorodifluoroacetate, silver 3,3, 3-trifluoropropionate, silver pentafluoropropionate, silver heptafluorobutyrate, silver heptafluoroisobutyrate, silver perfluorovalerate, silver perfluorohexanoate, silver perfluoroheptanoate, silver perfluorooctanoate, silver acetate, silver propionate, silver butyrate, silver isobutyrate, silver valerate, silver hexanoate, silver ethylbutyrate, silver monochloroacetate, silver dichloroacetate, silver trichloroacetate, silver pivalate; formula R¹²C(＝O)CH＝C(-OAg)-R¹³Wherein R is¹²And R¹³Independently of one another are C₁-C₈Alkyl in which part of the hydrogen atoms may be replaced by F, or optionally substituted phenyl, such as silver acetylacetonate, silver 1,1, 1-trifluoroacetylacetonate, silver 1,1,1,5,5, 5-hexafluoroacetylacetonate, silver 1-phenyl-4, 4, 4-trifluorobutanedione, silver 1- (4-methoxyphenyl) -4,4, 4-trifluorobutanedione; formula R¹⁴OC(＝O)CH＝C(-OAg)-R¹⁵Wherein R is¹⁴Is C₁-C₈Alkyl radical, R¹⁵Is C₁-C₈Alkyl in which a part of hydrogen atoms may be replaced by F, such as a silver complex of ethyl acetoacetate, a silver complex of ethyl 3-oxo-4, 4, 4-trifluorobutyrate; and mixtures thereof,

acid b2) is selected from monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, difluoroacetic acid, trifluoroacetic acid, pentafluoropropionic acid, heptafluorobutyric acid, perfluorovaleric acid, perfluorohexanoic acid, perfluoroheptanoic acid, perfluorooctanoic acid and 1,1,1,5,5, 5-hexafluoroacetylacetone and mixtures thereof,

solvent b3) is selected from the group consisting of water, alcohols (e.g. methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, tert-butanol, tert-amyl alcohol), cyclic or acyclic ethers (e.g. diethyl ether, tetrahydrofuran and 2-methyltetrahydrofuran), ketones (e.g. acetone, 2-butanone, 3-pentanone), ether-alcohols (e.g. 2-methoxyethanol, 1-methoxy-2-propanol, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether and diethylene glycol monobutyl ether), polar aprotic solvents (e.g. acetonitrile, dimethylformamide and dimethyl sulfoxide) and mixtures thereof, and

polyhydric phenol b4) is of formula

14. Use of a coating or printing ink composition according to claim 12 or 13 for the preparation of a highly reflective layer comprising silver nanoparticles.

Examples