Light pressure double-sensitive leuco coating composition and compression-resistant anti-counterfeiting paper

Abstract

The invention discloses a light pressure dual-sensitive leuco coating composition and compression-resistant anti-counterfeiting paper.The coating composition comprises a first component and a second component which are used for coating different areas of paper to form films, and the first component comprises composite dye microcapsule emulsion, an adhesive and a silane coupling agent; the second component comprises the following raw materials: a film-forming agent, a color developing agent, an auxiliary agent, a filler and an adhesive. The invention has the advantages that the leuco film layer formed by the first component has both the organic fluorescent dye and the leuco dye, not only can display fluorescence during ultraviolet irradiation, but also can develop color when the friction film layer formed by the second component applies pressure to the leuco film layer and rubs, and the two developing effects and the anti-counterfeiting effect are better; the leuco film layer and the friction film layer are arranged in different areas of the paper, under the condition that the leuco film layer and the friction film layer are not folded to make contact with each other, when one of the film layers is independently pressed, color development is avoided, and therefore in the coating process and the transportation process, the problem of accidental color development does not exist even if the film layers are pressed.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of special coating and anti-fake paper, and particularly relates to a light-pressure dual-sensitive leuco coating composition and pressure-resistant anti-fake paper. BACKGROUND

[0002] Special coating refers to a new functional coating different from traditional coating, which is endowed with special properties such as anti-sticking, self-cleaning, high-temperature resistance, corrosion resistance, heat insulation and anti-fake through special formula and process. The special anti-fake coating is used for coating on the surface of paper or plastic film to form anti-fake paper or film, which shows specific color that cannot be observed under normal circumstances when the conditions are met (ultraviolet irradiation or pressure).

[0003] Anti-fake paper is a special paper formed by combining modern anti-fake technology with paper, which is mainly applied to the anti-fake of bills, product packaging and certificates. According to different preparation methods, anti-fake paper can be divided into two categories: one is to use anti-fake technology in the paper pulp making process, such as adding photochromic, thermochromic fiber or other special sensitive components to the paper pulp; the other is to make anti-fake treatment on the surface of the paper after the paper is formed, such as making watermarks, coating leuco coating and the like.

[0004] CN2014105055316 discloses a leuco anti-fake paper, which applies coating containing leuco dye microcapsules and color developing agent to the surface of paper and dries to obtain a finished product. The deficiency is that: the leuco dye microcapsules and color developing agent are mixed to obtain leuco coating, on the one hand, the microcapsules may be broken in the preparation process due to slight carelessness, resulting in coating color development and waste, on the other hand, the microcapsules may also be broken due to uneven equipment or excessive application pressure during application on the paper surface, and in addition, accidental collision and pressure during transportation, packaging or use of the finished anti-fake paper will cause the paper to color prematurely. SUMMARY

[0005] The present application provides a light-pressure dual-sensitive leuco coating composition and pressure-resistant anti-fake paper, which aims to at least partially overcome the above-mentioned deficiencies of the existing leuco anti-fake paper.

[0006] The technical solution of the present application to solve the above technical problems is as follows: a light-pressure dual-sensitive leuco coating composition, which comprises a first component and a second component for applying and forming films on different areas of paper, the first component comprises the following raw materials in parts by weight: composite dye microcapsule emulsion 20-30 parts, adhesive 6-12 parts, silane coupling agent 0.5-1.5 parts; the second component comprises the following raw materials in parts by weight: film forming agent 8-16 parts, color developing agent 4-10 parts, auxiliary agent 3-8 parts; filler 30-50 parts, adhesive 20-30 parts.

[0007] On the basis of the above technical solutions, the application can further have the following specific or more optimal choices.

[0008] Specifically, the composite dye microcapsule emulsion is prepared by the following method:

[0009] S1. Take 1-3 parts of organic fluorescent dye and dissolve them in 6-10 parts of a mixed solvent of ethyl acetate and turpentine, then add 1-3 parts of leuco dye, stir and dissolve to obtain an oil phase, which is ready for use;

[0010] S2. Take 4-8 parts of PVA and dissolve them in 100 parts of water, heat and stir to dissolve, then add 0.5-1.2 parts of water-soluble carboxymethyl chitosan and stir to dissolve, then continue to add 1-3 parts of polyol under stirring to obtain an aqueous phase;

[0011] S3. Slowly add the oil phase of S1 to the aqueous phase of S2, and after sufficient stirring, the composite dye microcapsule emulsion is obtained.

[0012] It should be noted that during the preparation of the composite dye microcapsule emulsion, the long chains of the larger amount of PVA will be adsorbed on the surface of the oil droplets to form a hydrophilic protective layer, and the smaller amount of water-soluble carboxymethyl chitosan will have a certain gelation effect with the PVA in the hydrophilic protective layer, enhancing the stability and toughness of the hydrophilic protective layer. In particular, during the preparation and coating of the paint, the microcapsules containing dyes will not easily break, and have good stability; when coated on paper and dried, the microcapsules can withstand a certain pressure without breaking, but will only crack and release the leuco dye under the action of a larger pressure and frictional tearing.

[0013] Specifically, the organic fluorescent dye in S1 is an organic invisible fluorescent powder or invisible fluorescent ink, and the leuco dye is a fluoran black ODB-1, a fluoran black ODB-2, a crystal violet lactone, or a methyl ethyl crystal violet lactone (a mixture of methyl crystal violet lactone and ethyl crystal violet lactone).

[0014] It should be noted that the leuco dye is preferably one of the above-mentioned dyes, but can also be other commonly available commercial leuco dyes that exhibit blue, red, orange, green, yellow, and black colors after activation, including phthalides, fluorans, and phenothiazines.

[0015] Preferably, the organic invisible fluorescent powder is a solid powder that appears white, light yellow, or light pink under natural light and bright red, blue, yellow, or orange under ultraviolet light.

[0016] Specifically, the volume ratio of ethyl acetate to turpentine in S1 is 5-10:1.

[0017] Preferably, the PVA in S2 is PVA217 or PVA224.

[0018] Preferably, the adhesive in the first component is carboxyl styrene butadiene emulsion, and the silane coupling agent is KH560 or JH-M902.

[0019] Specifically, the film forming agent in the first component is PVA217 or PVA224, the color developing agent is bisphenol A or salicylic acid, the auxiliary agent is one or more of fatty alcohol polyoxyethylene ether, cationic polyacrylamide and vinyl emulsion, the filler is one or more of silica powder, silica gel powder or zirconia powder, and the adhesive is carboxyl styrene butadiene emulsion. The above-mentioned fillers can significantly enhance the hardness and roughness of the film forming area of the second component, so as to ensure that when the film forming area of the second component is pressed and rubbed against the film forming area of the first component, the composite dye microcapsules can be broken better, so that the leuco dye contacts with the acidic color developing agent to develop color.

[0020] The application also provides an anti-pressure anti-counterfeiting paper, which comprises a base paper and a leuco film layer and a rubbing film layer formed on different areas of the surface of the base paper. The leuco film layer is formed by applying and drying the first component of the above-mentioned light-pressure dual-sensitive leuco coating composition, and the rubbing film layer is formed by applying and drying the second component of the light-pressure dual-sensitive leuco coating composition.

[0021] Specifically, the base paper is in the shape of a rectangle, the leuco film layer is located at one end of the front surface of the base paper close to the wide side, the rubbing film layer is located at the other end of the front surface of the base paper, the area between the leuco film layer and the rubbing film layer of the base paper is a blank area, and the blank area is provided with a tear line or a fold line. The paper piece with the rubbing film layer of the base paper can be easily torn along the tear line, and then the paper piece can be conveniently inverted and covered on the leuco film layer for pressure and reciprocating rubbing to develop color. The fold line facilitates folding the area with the rubbing film layer of the base paper to the area with the rubbing film layer, so that the rubbing film layer contacts with the leuco film layer for pressure and reciprocating rubbing to develop color.

[0022] Compared with the prior art, the application has the following beneficial effects:

[0023] The light pressure double-sensitive hidden color coating composition provided by the present application comprises a first component and a second component for film forming on different areas of paper, wherein the first component forms a hidden color film layer containing composite dye microcapsules, and has organic fluorescent dye and hidden color dye, which can develop color (fluorescence) under ultraviolet light irradiation, and can also develop color when the second component forms a rubbing film layer and presses and rubs the hidden color film layer, and the two color developing effects can play a double anti-counterfeiting effect, and the anti-counterfeiting effect is better. At the same time, since the hidden color film layer and the rubbing film layer are in different areas of the paper, under the condition that the two film layers are not folded to contact each other, when pressure is applied to one of the film layers alone, since the hidden color dye and the color developing agent cannot contact each other, the hidden color dye and the color developing agent cannot develop color, so during the application process and the transportation process, even if pressure is applied, there will be no problem of accidental color development, that is, the anti-counterfeiting paper obtained has the pressure resistance effect that similar anti-counterfeiting papers do not have. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A schematic diagram of the pressure-resistant anti-counterfeiting paper prepared by the present application is shown, and the anti-counterfeiting paper is provided with a folding line;

[0025] Figure 2 A schematic diagram of another pressure-resistant anti-counterfeiting paper prepared by the present application is shown, and the anti-counterfeiting paper is provided with a tearing line;

[0026] Figure 3 A Figure 2 A sectional view along A-A of the pressure-resistant anti-counterfeiting paper shown in the figure.

[0027] In the drawings, the components represented by each reference numeral are listed as follows:

[0028] 1, hidden color film layer; 2, rubbing film layer; 3, folding line; 4, tearing line. DETAILED DESCRIPTION

[0029] The technical solutions provided by the present application will be described clearly and completely below in combination with the drawings and specific embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the scope of protection of the present application.

[0030] For brevity, the drug raw materials used in the following examples are all commercially available products if not otherwise specified, and the methods used are all conventional methods in the art if not otherwise specified.

[0031] The organic fluorescent dye is an organic invisible fluorescent powder or invisible fluorescent ink, which appears white, light yellow or light pink under natural light and presents bright red, blue, yellow or orange under ultraviolet light, such as invisible ultraviolet fluorescent red UVA-RT98, invisible fluorescent green UVA-Z09, fluorescent blue UVA-A1 or ultraviolet fluorescent blue ink UF1307-B available on the market; the fineness of the silica powder, silica gel powder and zirconium dioxide powder in the filler is controlled in the micron level, and preferably, the ultra-fine powder with a particle size ranging from 1 to 10 microns is used.

[0032] Example 1

[0033] A light pressure dual-sensitive invisible color coating composition, which comprises a first component and a second component for applying a film to different areas of paper, the first component comprises the following weight parts of each raw material: composite dye microcapsule emulsion 25 parts, carboxyl styrene emulsion 8 parts, KH560 1.2 parts; the second component comprises the following weight parts of each raw material: film forming agent PVA224 10 parts, bisphenol A 8 parts, fatty alcohol polyoxyethylene ether 5 parts; silica powder 42 parts, carboxyl styrene emulsion 27 parts. When the first component corresponding coating is prepared, 25 parts by weight of the composite dye microcapsule emulsion is taken, and under stirring conditions, the above-mentioned weight parts of carboxyl styrene emulsion and KH560 are sequentially added, and an appropriate amount of water is supplemented, and after mixing, a uniform suspension with a solid content of (13±0.5)% is obtained, which is ready for use; when the second component corresponding coating two is prepared, a certain amount of water is taken and the second component corresponding formula weight parts of film forming agent PVA224, fatty alcohol polyoxyethylene ether and carboxyl styrene emulsion are added to the water and mixed uniformly, and then the corresponding weight parts of bisphenol A and silica powder are sequentially added, and an appropriate amount of water is supplemented, and after mixing, a uniform suspension with a solid content of (12±0.5)% is obtained, which is ready for use.

[0034] The above-mentioned composite dye microcapsule emulsion is prepared by the following method:

[0035] S1. Take invisible ultraviolet fluorescent red UVA-RT98 2 parts (weight parts, the same below) and dissolve it in 9 parts of a mixed solvent of ethyl acetate and turpentine (volume ratio 5:1), then add fluoran black ODB-2 2 parts, stir and dissolve to obtain an oil phase, ready for use;

[0036] S2. Take 7 parts of PVA224 and dissolve it in 100 parts of water, heat and stir to dissolve, then add 0.9 parts of water-soluble carboxymethyl chitosan and stir to dissolve, then continue to add 2 parts of polyol under stirring to obtain an aqueous phase;

[0037] S3. Slowly add the oil phase of S1 to the aqueous phase of S2, and after stirring thoroughly, the composite dye microcapsule emulsion is obtained.

[0038] Preparation of the anti-press security paper using the above light-press double-sensitive hidden color coating composition is as follows:

[0039] In the pulping and papermaking process, the coating 1 is first used to surface size a specific area of one end of the paper (base paper), and then the coating 2 is used to surface size a specific area of the other end, and then dried, forming a hidden color film layer 1 and a rubbing film layer 2 at the two ends of the paper, respectively. The blank area between the two film layers forms a folding line 3 by indentation method. The surface structure of the obtained anti-press security paper is shown in Figure 1 The hidden color film layer 1 has no obvious difference in color with the blank area when not activated (no ultraviolet light irradiation or no action with the rubbing film layer), and the rubbing film layer 2 is obviously rougher than other areas.

[0040] Security detection: The anti-press security paper obtained by ultraviolet light irradiation detection shows orange-red fluorescence at one end of the hidden color film layer 1, and the orange-red fluorescence disappears when the ultraviolet lamp is turned off. When the rubbing film layer 2 is folded towards the hidden color film layer 1 and pressed and rubbed (the rubbing action can both break the microcapsules and heat the contact surface), black marks can be seen on the hidden color film layer and the rubbing film layer after continuous action, and the marks on the hidden color film layer are thicker. When the two ends of the anti-press security paper do not overlap, they do not show color when pressed separately.

[0041] Example 2

[0042] A light-press double-sensitive hidden color coating composition includes a first component and a second component for applying film to different areas of the paper. The first component includes the following raw materials in parts by weight: composite dye microcapsule emulsion 20 parts, carboxyl styrene emulsion 6 parts, KH560 1.5 parts; the second component includes the following raw materials in parts by weight: film former PVA224 12 parts, bisphenol A 9 parts, fatty alcohol polyoxyethylene ether 8 parts; silica powder 50 parts, carboxyl styrene emulsion 30 parts. When preparing the corresponding coating 1 of the first component, 20 parts by weight of the composite dye microcapsule emulsion is taken, and under stirring conditions, the carboxyl styrene emulsion and KH560 of the above formulation are added in sequence, and the appropriate amount of water is supplemented, and after mixing, a uniform suspension with a solid content of (14±0.5)% is obtained, which is ready for use; when preparing the corresponding coating 2 of the second component, a certain amount of water is first taken and the film former PVA224, fatty alcohol polyoxyethylene ether and carboxyl styrene emulsion of the corresponding formulation of the second component are added to the water and mixed uniformly, and then the corresponding amount of bisphenol A and silica powder is added in sequence, and the appropriate amount of water is supplemented, and after mixing, a uniform suspension with a solid content of (14±0.5)% is obtained, which is ready for use.

[0043] The above composite dye microcapsule emulsion is prepared by the following method:

[0044] S1. Take the invisible fluorescent green UVA-Z09 1 part in 6 parts of ethyl acetate and turpentine mixed solvent (volume ratio 7:1), then add fluoran black ODB-2 3 parts, stir to dissolve, get oil phase, ready for use;

[0045] S2. Take 8 parts of PVA224 dissolved in 100 parts of water, heated and stirred to dissolve, then add 1.2 parts of water-soluble carboxymethyl chitosan and stir to dissolve, then continue to add 1 part of polyol under stirring, get water phase;

[0046] S3. Slowly add the oil phase of S1 to the water phase of S2, stir well, and get the composite dye microcapsule emulsion.

[0047] The above light pressure dual-sensitive invisible coating composition is used to prepare pressure-resistant anti-fake paper, as follows:

[0048] In the pulping and papermaking process, first use coating 1 to surface size a specific area of one end of the paper, then use coating 2 to surface size a specific area of the other end, and then dry, the two ends of the paper form invisible film layer 1 and friction film layer 2 respectively, the blank area between the two film layers forms a tear line 4 in the form of a stamp hole, the structure of the obtained pressure-resistant anti-fake paper is shown in Figure 2 and 3 The invisible film layer 1 has no obvious difference in color with the blank area paper surface when not activated (no ultraviolet light irradiation or no action with the friction film layer), and the friction film layer 2 is obviously rougher than other areas.

[0049] Anti-fake detection: the obtained pressure-resistant anti-fake paper is detected by ultraviolet light irradiation, the invisible film layer at one end will appear green fluorescence, and the green fluorescence will disappear when the ultraviolet lamp is turned off; tear off the friction film layer along the tear line, then use it to press and quickly rub the invisible film layer, black marks can be seen on the invisible film layer and the friction film layer, and the marks on the invisible film layer are thicker. When the two ends of the pressure-resistant anti-fake paper do not overlap, they are not colored separately when pressure is applied.

[0050] Example 3

[0051] A light pressure double-sensitive leuco coating composition, which comprises a first component and a second component for applying film to different areas of paper, the first component comprises the following raw materials in parts by weight: composite dye microcapsule emulsion 28 parts, carboxyl styrene emulsion 12 parts, JH-M902 0.5 parts; the second component comprises the following raw materials in parts by weight: film former PVA224 48 parts, salicylic acid 6 parts, vinyl emulsion 6 parts; silica powder 35 parts, carboxyl styrene emulsion 25 parts. The first component corresponds to the preparation of coating 1, take 28 parts by weight of composite dye microcapsule emulsion, under stirring conditions, add the above formula weight parts of carboxyl styrene emulsion and JH-M902 in turn, supplement with appropriate amount of water, mix uniformly, then get a uniform suspension with solid content of (13±0.5)%, ready for use; the second component corresponds to the preparation of coating 2, first take a certain amount of water and mix the second component corresponding formula weight parts of film former PVA224, vinyl emulsion and carboxyl styrene emulsion in water, then add the corresponding weight parts of salicylic acid and silica powder in turn, supplement with appropriate amount of water, mix uniformly, then get a uniform suspension with solid content of (13±0.5)%, ready for use.

[0052] The above-mentioned composite dye microcapsule emulsion is prepared by the following method:

[0053] S1. Take fluorescent blue UVA-A1 3 parts dissolved in 10 parts of mixed solvent of ethyl acetate and turpentine (volume ratio 10:1), then add 1 part of methyl ethyl crystal violet lactone, stir and dissolve, get oil phase, ready for use;

[0054] S2. Take 6 parts of PVA224 dissolved in 100 parts of water, heat and stir to dissolve, then add 0.5 parts of water-soluble carboxymethyl chitosan and stir to dissolve, then continue to add 3 parts of polyol under stirring, get water phase;

[0055] S3. Slowly add the oil phase of S1 to the water phase of S2, stir thoroughly, then get the composite dye microcapsule emulsion.

[0056] The above-mentioned light pressure double-sensitive leuco coating composition is used to prepare pressure-resistant anti-fake paper, as follows:

[0057] In the pulp and papermaking process, first use coating 1 to surface size the paper at one end of the specified area, then use coating 2 to surface size the other end of the specified area, then dry, the two ends of the paper form leuco film layer and friction film layer respectively, and the blank area between the two film layers forms a crease line by indentation method. The leuco film layer has no obvious difference with the blank area when not activated (no ultraviolet light irradiation or no action with friction film layer), and the friction film layer is obviously rougher than other areas.

[0058] Anti-forgery detection: the anti-pressing anti-forgery paper obtained by detection under ultraviolet light irradiation shows blue fluorescence at one end of the leuco film layer, and the blue fluorescence disappears when the ultraviolet lamp is turned off; when the rubbing film layer is folded towards the leuco film layer and pressed and rubbed, blue-purple marks can be seen on the leuco film layer and the rubbing film layer, and the marks on the leuco film layer are darker. The anti-pressing anti-forgery paper does not show color when the two ends are not overlapped and are separately subjected to pressure.

[0059] Example 4

[0060] A light-pressure dual-sensitive leuco coating composition includes a first component and a second component for film application to different areas of paper, the first component includes the following weight parts of each raw material: composite dye microcapsule emulsion 30 parts, carboxyl styrene emulsion 10 parts, JH-M902 1 part; the second component includes the following weight parts of each raw material: film former PVA217 16 parts, salicylic acid 4 parts, vinyl emulsion 3 parts; silicon dioxide powder 30 parts, carboxyl styrene emulsion 20 parts. When preparing the first component corresponding coating, 30 parts by weight of composite dye microcapsule emulsion is taken, and under stirring conditions, the above-mentioned weight parts of carboxyl styrene emulsion and JH-M902 are sequentially added, and an appropriate amount of water is supplemented, and after mixing, a uniform suspension with a solid content of (12±0.5)% is obtained, which is ready for use; when preparing the second component corresponding coating two, a certain amount of water is first taken and the second component corresponding formula weight parts of film former PVA217, vinyl emulsion and carboxyl styrene emulsion are added to the water and mixed uniformly, then the corresponding weight parts of salicylic acid and silicon dioxide powder are sequentially added, and an appropriate amount of water is supplemented, and after mixing, a uniform suspension with a solid content of (13±0.5)% is obtained, which is ready for use.

[0061] The above-mentioned composite dye microcapsule emulsion is prepared by the following method:

[0062] S1. Take 1 part of ultraviolet fluorescent blue ink UF1307-B and dissolve it in 6 parts of a mixed solvent of ethyl acetate and turpentine (volume ratio 6:1), then add 1 part of crystal violet lactone, stir and dissolve to obtain an oil phase, ready for use;

[0063] S2. Take 4 parts of PVA217 and dissolve it in 100 parts of water, heat and stir to dissolve, then add 1 part of water-soluble carboxymethyl chitosan and stir to dissolve, then continue to add 1 part of polymeric polyol under stirring to obtain an aqueous phase;

[0064] S3. Slowly add the oil phase of S1 to the aqueous phase of S2, and after stirring thoroughly, the composite dye microcapsule emulsion is obtained.

[0065] The above-mentioned light-pressure dual-sensitive leuco coating composition is used to prepare anti-pressing anti-forgery paper, which is prepared as follows:

[0066] In the process of pulping and papermaking, a coating is first used to surface size a specific area of one end of a paper sheet, then a second coating is used to surface size a specific area of the other end of the paper sheet, and then drying treatment is performed, so that a colorless film layer and a rubbing film layer are formed at the two ends of the paper sheet respectively, and an easy folding line is formed in the blank area between the two film layers. The colorless film layer has no obvious color difference with the paper surface in the blank area when it is not activated (no ultraviolet light irradiation or no action with the rubbing film layer), and the rubbing film layer is obviously rougher than other areas.

[0067] Anti-fake detection: the anti-press anti-fake paper obtained by ultraviolet light irradiation detection shows blue fluorescence at one end of the colorless film layer, and the blue fluorescence disappears when the ultraviolet lamp is turned off; when the rubbing film layer is folded towards the colorless film layer and pressed and rubbed, blue marks can be seen on the colorless film layer and the rubbing film layer, and the marks on the colorless film layer are thicker. When the two ends of the anti-press anti-fake paper do not overlap, they do not show color when they are individually subjected to pressure.

[0068] The above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An optical pressure dual-sensitive leuco coating composition characterized in that, The first component for film forming on different areas of paper comprises the following raw materials in parts by weight: composite dye microcapsule emulsion 20-30 parts, adhesive 6-12 parts, silane coupling agent 0.5-1.5 parts; the second component comprises the following raw materials in parts by weight: film forming agent 8-16 parts, color developing agent 4-10 parts, auxiliary agent 3-8 parts; filler 30-50 parts, adhesive 20-30 parts.

2. An optical pressure dual-sensitive leuco coating composition according to claim 1, characterized in that, The composite dye microcapsule emulsion is prepared by the following method: S1. Dissolve 1-3 parts of organic fluorescent dye in 6-10 parts of mixed solvent of ethyl acetate and turpentine, then add 1-3 parts of leuco dye, stir and dissolve to obtain an oil phase, ready for use; S2. Dissolve 4-8 parts of PVA in 100 parts of water, heat and stir to dissolve, then add 0.5-1.2 parts of water-soluble carboxymethyl chitosan and stir to dissolve, then continue to add 1-3 parts of polyol under stirring to obtain an aqueous phase; S3. Slowly add the oil phase of S1 to the aqueous phase of S2, and fully stir to obtain a composite dye microcapsule emulsion.

3. A photochromic dual-responsive leuco coating composition according to claim 2, wherein, The organic fluorescent dye in S1 is an organic invisible fluorescent powder or invisible fluorescent ink, and the leuco dye is fluoran black ODB-1, fluoran black ODB-2, crystal violet lactone or methyl ethyl crystal violet lactone.

4. A photochromic dual-responsive leuco coating composition according to claim 3, wherein, The organic invisible fluorescent powder is a solid powder that appears white, light yellow or light pink under natural light and bright red, blue, yellow or orange under ultraviolet light.

5. An optical pressure-sensitive dual-responsive leuco coating composition according to claim 2, wherein The volume ratio of ethyl acetate to turpentine in S1 is 5-10:

1.

6. The opto-pressentive dual-responsive leuco coating composition according to claim 1, wherein The PVA in S2 is PVA217 or PVA224.

7. The opto-pressentive dual-responsive leuco coating composition according to claim 1, wherein The adhesive in the first component is a carboxyl styrene emulsion, and the silane coupling agent is KH560 or JH-M902.

8. A photochromic dual-responsive leuco coating composition according to any one of claims 1 to 7, characterised in that, The film forming agent in the first component is PVA217 or PVA224, the color developing agent is bisphenol A or salicylic acid, the auxiliary agent is one or more of fatty alcohol polyoxyethylene ether, cationic polyacrylamide and vinyl emulsion, the filler is one or more of silica powder, silica gel powder or zirconium oxide powder, and the adhesive is a carboxyl styrene emulsion.

9. A security paper resistant to compression, characterized in that, The pressure-resistant anti-fake paper comprises a base paper and leuco film layers and friction film layers formed on different areas of the surface of the base paper, the leuco film layers are formed by applying and drying the first component of the light pressure dual-sensitive leuco coating composition according to any one of claims 1 to 8, and the friction film layers are formed by applying and drying the second component of the light pressure dual-sensitive leuco coating composition.

10. The security paper according to claim 9, characterized in that, The base paper is in the shape of a rectangle, the leuco film layers are located at one end of the front surface of the base paper near the wide side, the friction film layers are located at the other end of the front surface of the base paper, the area between the leuco film layers and the friction film layers of the base paper is a blank area, and the blank area is provided with a tear line or a fold line.

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