阅读说明：本技术 用于热敏印刷的防篡改介质 (Tamper-resistant media for thermal printing ) 是由 罗格·博尔斯特伦 吉尔伯特·博蒂 菲利普·亨齐克 于 2018-06-12 设计创作，主要内容包括：本发明涉及制造用于热敏印刷的防篡改介质的方法,其中将包含至少一种酸的液体处理组合物5沉积在包括包含至少一种酸碱显色的隐色染料的热致变色涂覆层的基材上。(The present invention relates to a method of manufacturing a tamper-resistant medium for thermal printing, wherein a liquid treatment composition 5 comprising at least one acid is deposited on a substrate comprising a thermochromic coating layer comprising at least one acid-base-developing leuco dye.)

1. A method of manufacturing a tamper-resistant media for thermal printing, the method comprising the steps of:

a) providing a substrate, wherein the substrate comprises on at least one side a thermochromic coating layer comprising at least one acid-base-developing leuco dye,

b) providing a liquid treatment composition comprising at least one acid, and

c) applying the liquid treatment composition in the form of a pre-selected pattern on at least one area of the thermochromic coating layer.

2. The method of claim 1, wherein the substrate is selected from the group comprising: paper, cardboard for containers, plastic, cellophane, fabric, wood, metal, glass, mica or nitrocellulose, preferably paper, cardboard for containers or plastic.

3. The method of any one of the preceding claims, wherein the at least one acid-base chromogenic leuco dye is colorless.

4. The method of any one of the preceding claims, wherein the at least one acid-base chromogenic leuco dye is selected from the group consisting of arylmethanephthalide dyes, quinone dyes, triarylmethane dyes, triphenylmethane dyes, fluoran dyes, phenothiazine dyes, rhodamine lactam dyes, spiropyran dyes, and mixtures thereof.

5. The method according to any of the preceding claims, wherein the thermochromic coating layer comprises the at least one acid-base-developing leuco dye in an amount of from 1 to 60 wt. -%, preferably from 5 to 55 wt. -%, more preferably from 10 to 50 wt. -%, even more preferably from 15 to 45 wt. -%, and most preferably from 20 to 40 wt. -%, based on the total weight of the thermochromic coating layer.

6. The method according to any of the preceding claims, wherein the thermochromic coating layer further comprises a colour developer in an amount of from 1 to 80 wt. -%, preferably from 10 to 75 wt. -%, more preferably from 20 to 70 wt. -%, even more preferably from 30 to 65 wt. -%, and most preferably from 40 to 60 wt. -%, based on the total weight of the thermochromic coating layer.

7. The process according to any one of the preceding claims, wherein the at least one acid is selected from hydrochloric acid, sulfuric acid, sulfurous acid, phosphoric acid, citric acid, oxalic acid, acetic acid, formic acid, sulfamic acid, tartaric acid, phytic acid, boric acid, succinic acid, suberic acid, benzoic acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, isocitric acid, aconitic acid, propane-1, 2, 3-tricarboxylic acid, trimesic acid, glycolic acid, lactic acid, mandelic acid, acidic organosulfur compounds, acidic organophosphorus compounds, at least partially selected from Li⁺、Na⁺、K⁺、Mg²⁺Or Ca²⁺Corresponding cation-neutralized HSO of₄ ^-、H₂PO₄ ^-Or HPO₄ ^2-And mixtures thereof, preferably the at least one acid is selected from the group consisting of hydrochloric acid, sulfuric acid, sulfurous acid, phosphoric acid, oxalic acid, boric acid, suberic acid, succinic acid, sulfamic acid, tartaric acid, and mixtures thereof, more preferably the at least one acid is selected from the group consisting of sulfuric acid, phosphoric acid, boric acid, suberic acid, sulfamic acid, tartaric acid, and mixtures thereof, and most preferably the at least one acid is phosphoric acid.

8. The method of any preceding claim, wherein the liquid treatment composition further comprises a dye, a pigment, a fluorescent dye, a phosphorescent dye, an ultraviolet absorbing dye, a near infrared absorbing dye, a thermochromic dye, an acid-base chromogenic dye, a metal ion, a transition metal ion, a lanthanide, an actinide, a magnetic particle, a quantum dot, or mixtures thereof, preferably the liquid treatment composition comprises a dye, and most preferably a solvent soluble dye.

9. The method according to any preceding claims, wherein the liquid treatment composition comprises the at least one acid in an amount of from 0.1 wt% to 100 wt%, preferably in an amount of from 1 wt% to 80 wt%, more preferably in an amount of from 3 wt% to 60 wt%, and most preferably in an amount of from 10 wt% to 50 wt%, based on the total weight of the liquid treatment composition.

10. The method according to any of the preceding claims, wherein the preselected pattern is a pattern of successive layers, patterns of repeating elements and/or repeating combinations of elements, preferably the preselected pattern is a guilloche, one-dimensional barcode, two-dimensional barcode, three-dimensional barcode, QR code, dot matrix code, security mark, number, letter, alphanumeric symbol, logo, image, shape, signature, design or a combination thereof.

11. The method according to any one of the preceding claims, wherein the liquid treatment composition is applied by spraying, ink jet printing, offset printing, flexographic printing, screen printing, plotting, contact embossing, rotogravure printing, spin coating, slot coating, curtain coating, slide bed coating, film pressing, metered film pressing, doctor blade coating, brushing, embossing and/or a writing head, and preferably by ink jet printing.

12. A tamper-resistant medium for thermal printing obtainable by the method according to any one of claims 1 to 11.

13. The tamper-resistant medium according to claim 12, wherein the tamper-resistant medium is a branded product, a security document, a non-security document or a decorative product, preferably the product is a package, a container, a Compact Disc (CD), a Digital Video Disc (DVD), a blu-ray disc, a sticker, a mark, a seal, a label, a poster, a passport, a driver's license, a bank card, a credit card, a bond, a ticket, a stamp, a tax stamp, a banknote, a certificate, a brand authentication label, a business card, a greeting card, a voucher, a tax banderole, a point of sale receipt, a chart, a facsimile, a continuous recording slip or roll paper or wallpaper.

14. Use of the tamper-resistant medium for thermal printing according to claim 12 or 13 in: security applications, overt security elements, covert security elements, brand protection, deviation prevention, miniature characters, micro-imaging, decorative applications, artistic applications, visual applications, packaging applications, printing applications, surveillance applications, or tracking and tracing applications.

Description of the drawings:

figure 1 shows an enlarged view of a substrate made according to example 1.

Fig. 2 shows a tamper-resistant medium for thermal printing made according to example 2, with a portion of the original print removed by an erasing liquid.

Figure 3 shows an enlarged view of the portion highlighted in figure 2 before application of the liquid treatment composition.

Figure 4 shows an enlarged view of the portion highlighted in figure 2 after application of the liquid treatment composition.

Figure 5 shows an enlarged view of the portion highlighted in figure 2 after application of the wiping liquid.

Fig. 6 shows an enlarged infrared image of the portion highlighted in fig. 2 after application of the erasing liquid.

Fig. 7 shows an enlarged infrared image of a tamper-resistant media for thermal printing made according to example 3, with the original print removed by an erase fluid.

Fig. 8 shows two tamper-resistant media for thermal printing made according to example 4, wherein the left-side logo was printed with a liquid treatment composition containing a red dye.

Fig. 9 shows two tamper-resistant media for thermal printing made according to example 4, wherein the left-hand logo is printed with a liquid treatment composition containing a red dye, and wherein the logo is partially removed by a wiping liquid.

Examples

Hereinafter, the measurement method carried out in the examples is described.

1. Method and material

Photograph

Images of the prepared samples were recorded with a file detector PF-3000(Ribao Technology, china).

Base material

S1 Ticket M ü nchner Verkehrs-und Tariffverband (MVV) commercially available from a ticket vending machine in Munich, Germany.

S2: a ticket from the german federal railway company, Deutsche Bahn AG (DB), commercially available from ticket machines in stuttgart, germany.

S3: tickets commercially available from the ticket vending machine of Oftringen, switzerland federal railway company (schweizerischebundesbahnen (sbb)). The thermochromic coating layer of the ticket paper comprises calcium carbonate as filler.

Liquid treatment composition

L1: 41 wt% phosphoric acid, 24 wt% ethanol and 35 wt% water (wt% based on the total weight of the liquid treatment composition).

L2: 41 wt% phosphoric acid, 24 wt% ethanol, 34 wt% water, and 1 wt% amaranth (wt% is based on the total weight of the liquid treatment composition).

Erasing liquid

Potassium hydroxide solution (1.0M)