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 2018-07-25 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。所述层可在透射和反射时显示出不同的颜色。本发明进一步涉及一种装饰和安全元件。当将所述层施加至安全元件(例如全息图)上时，所获得的产品可在反射和透射时可显示出不同的颜色，极亮的光学可变图像(OVD图像)。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 may exhibit different colors in transmission and reflection. The invention further relates to a decorative and security element. When the layer is applied to a security element, such as a hologram, the resulting product may exhibit different colours in reflection and transmission, an extremely bright optically variable image (OVD image). Depending on the layer thickness, a metallic appearance of either high or low strength is present.)

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

A) optionally forming a surface relief microstructure, in particular 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 surface relief microstructure obtained in step a), wherein the composition comprises:

b1) formula Ag⁺L^-(I) The metal complex of (1), wherein:

L^-is a formula

R¹is perfluoroalkyl or C in which a part of the hydrogen atoms has been replaced by fluorine atoms₁-C₈An alkyl group;

R²is a perfluoroalkyl group; c₁-C₈An alkyl group; c in which a part of the hydrogen atoms is replaced by fluorine atoms₁-C₈An alkyl group; optionally substituted by one or more C₁-C₄Alkyl or C₁-C₄Alkoxy-substituted phenyl; optionally substituted by one or more C₁-C₄Alkyl or C₁-C₄Alkoxy-substituted C₂-C₅A heteroaryl group; or C₁-C₈An alkoxy group,

R³is a hydrogen atom, a fluorine atom, a chlorine atom or C₁-C₈Alkyl, or

R²And R³Together form a monocyclic or bicyclic ring, which may optionally be substituted by one or more C₁-C₄The substitution of the alkyl group is carried out,

b2) a solvent, a water-soluble organic solvent,

b3) a reducing agent, and

b4) optionally a polymeric binder, and

b5) optionally a dispersing agent, and optionally a dispersing agent,

C) heating the coating obtained in step B) to a temperature below 120 ℃ and/or irradiating said coating with electromagnetic radiation, thereby forming a highly reflective layer comprising silver nanoparticles.

2. The process of claim 1 wherein the metal complex of formula (I) is prepared in situ from a silver compound selected from the group consisting of silver oxide, silver hydroxide, silver complexes with non-fluorinated β -diketones and β -ketoesters and mixtures thereof, and a compound of formula H⁺L^-Wherein L is^-As defined in claim 1.

3. The process according to claim 2, wherein formula H⁺L^-The compound of (a) is selected from:

(7, 7-dimethyl-1, 1,1,2,2,3, 3-heptafluoro-4, 6-octanedione),

(1,7, 7-trimethyl-3- (2,2, 2-trifluoroacetyl) norbornan-2-one),

(1,1, 1-trifluoro-2, 4-pentanedione),

(1,1,1,2, 2-pentafluoro-2, 4-hexanedione),

(5,5,6,6,7,7,8,8, 8-nonafluorooctane-2, 4-dione),

(5H, 5H-perfluorononane-4, 6-dione),

(4,4, 4-trifluoro-1-phenyl-1, 3-butanedione),

(4,4, 4-Trifluoroacetoacetic acid propyl ester),

and mixtures thereof.

4. A process according to any one of claims 1 to 3, wherein the solvent is selected from alcohols, cyclic or acyclic ethers, ketones, ether-alcohols, esters, polar aprotic solvents, mixtures thereof and mixtures with water.

5. The process according to any one of claims 1 to 4, wherein the reducing agent is a1, 2-diol, such as glycerol, ethylene glycol, 1, 2-propanediol, 1, 2-butanediol, 1, 2-pentanediol, 2, 3-butanediol, 1, 2-hexanediol, 2, 3-butanediol, cis-or trans-1, 2-cyclopentanediol, cis-or trans-1, 2-cyclohexanediol and erythritol, or an aldehyde, such as glutaraldehyde.

6. The method according to claim 5, wherein the reducing agent is glycerol or glutaraldehyde.

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 1-7, 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 a surface relief microstructure, particularly an OVD forming device; and

a3) curing the curable composition treated in step a 2).

9. The process according to any one of claims 1 to 8, wherein a protective coating is applied on the layer obtained in step C).

10. 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 9 on at least a portion of the surface of said substrate.

11. Use of an element according to claim 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) formula Ag⁺L^-(I) The metal complex of (1), wherein:

L^-is a formula

R¹is perfluoroalkyl or C in which a part of the hydrogen atoms has been replaced by fluorine atoms₁-C₈An alkyl group;

R²is a perfluoroalkyl group; c₁-C₈An alkyl group; c in which a part of the hydrogen atoms is replaced by fluorine atoms₁-C₈An alkyl group; optionally substituted by one or more C₁-C₄Alkyl or C₁-C₄Alkoxy-substituted phenyl; optionally substituted by one or more C₁-C₄Alkyl or C₁-C₄Alkoxy-substituted C₂-C₅A heteroaryl group; or C₁-C₈An alkoxy group,

R³is a hydrogen atom, a fluorine atom, a chlorine atom or C₁-C₈Alkyl, or

R²And R³Together form a monocyclic or bicyclic ring, which may optionally be substituted by one or more C₁-C₄The substitution of the alkyl group is carried out,

b2) a solvent, a water-soluble organic solvent,

b3) a reducing agent, and

b4) optionally a polymeric binder, and

b5) optionally a dispersant, provided that the solvent is different from the reducing agent.

13. A coating or printing ink composition according to claim 12, comprising:

b1) formula Ag⁺L^-(I) Wherein L is^-Is represented by the following formula H⁺L^-Deprotonated forms of the compounds:

(1,1, 1-trifluoro-2, 4-pentanedione),

(1,1,1,5,5,6,6, 6-octafluoro-2, 4-hexanedione),

14. A coating or printing ink composition according to claim 12 or 13, wherein the solvent is selected from alcohols, cyclic or acyclic ethers, ketones, ether-alcohols, esters, polar aprotic solvents, mixtures thereof and mixtures with water.

15. The coating or printing ink composition according to any of claims 12 to 14, wherein the reducing agent is a1, 2-diol, such as glycerol, ethylene glycol, 1, 2-propanediol, 1, 2-butanediol, 1, 2-pentanediol, 2, 3-butanediol, 1, 2-hexanediol, 2, 3-butanediol, cis-or trans-1, 2-cyclopentanediol, cis-or trans-1, 2-cyclohexanediol and erythritol, or an aldehyde, such as glutaraldehyde.

Examples