Anti-cracking hot melt pavement marking paint and preparation method thereof

Abstract

This invention relates to the field of road marking paint technology, and proposes a crack-resistant hot-melt pavement marking paint and its preparation method. The crack-resistant hot-melt pavement marking paint comprises the following raw materials in parts by weight: 10-30 parts petroleum resin, 45-60 parts filler, 5-8 parts EVA hot-melt adhesive, 2-4 parts plasticizer, 18-22 parts glass microspheres, 2-3 parts pigment, and 1.5-3 parts additives. The softening point of the petroleum resin is 91-95℃, the VA content of the EVA hot-melt adhesive is 32wt%-34wt%, and the melt index of the EVA hot-melt adhesive is 350-450g / 10min. This technical solution solves the problem of insufficient crack resistance in related technologies for hot-melt pavement marking paints.

Description

Technical Field

[0001] This invention relates to the field of road marking paint technology, specifically to a crack-resistant hot-melt road marking paint and its preparation method. Background Technology

[0002] As an indispensable component of the road traffic system, road markings play a crucial role in dividing lanes, guiding traffic, and warning of dangers, directly affecting road traffic efficiency and driving safety.

[0003] Hot-melt road marking paint has a wide range of applications, covering various types of roads such as highways, national and provincial trunk roads, urban main and secondary roads, airports, docks, residential areas and underground garages. It can be used to draw various traffic markings such as lane dividing lines, edge lines, zebra crossings, and parking space lines, and is one of the core materials to ensure the orderly operation of road traffic.

[0004] However, traditional hot-melt pavement marking paints currently on the market still suffer from insufficient crack resistance. Hot-melt pavement marking paints with insufficient crack resistance are prone to cracking under external forces and temperature changes, which can damage the integrity and continuity of the markings, rendering them unable to provide clear guidance and increasing driving safety hazards.

[0005] Therefore, it is very necessary to develop a crack-resistant hot-melt pavement marking paint. Summary of the Invention

[0006] This invention proposes a crack-resistant hot-melt pavement marking paint and its preparation method, which solves the problem of insufficient crack resistance of hot-melt pavement marking paints in related technologies.

[0007] This invention proposes a crack-resistant hot-melt pavement marking paint, comprising the following raw materials in parts by weight: 10-30 parts petroleum resin, 45-60 parts filler, 5-8 parts EVA hot melt adhesive, 2-4 parts plasticizer, 18-22 parts glass microspheres, 2-3 parts pigment, and 1.5-3 parts additives. The petroleum resin has a softening point of 91-95℃, the EVA hot melt adhesive has a VA content of 32wt%-34wt%, and the EVA hot melt adhesive has a melt index of 350-450g / 10min.

[0008] Preferably, the filler is composed of first heavy calcium carbonate, second heavy calcium carbonate, flaky talc, and barium sulfate in a mass ratio of 40:10:5 to 8:4, wherein the first heavy calcium carbonate and the second heavy calcium carbonate have different particle sizes.

[0009] Preferably, the particle size of the first heavy calcium carbonate is 400-425 mesh, the particle size of the second heavy calcium carbonate is 250-300 mesh, the particle size of the flaky talc is 800-1000 mesh, and the particle size of the barium sulfate is 1250-1500 mesh.

[0010] Preferably, the glass microspheres have a particle size of 80-100 mesh.

[0011] Preferably, the plasticizer includes one or more of dioctyl terephthalate, trioctyl trimellitate, and diisononyl phthalate.

[0012] Preferably, the pigment is rutile titanium dioxide.

[0013] Preferably, the additive consists of an antioxidant and an antifoaming agent in a mass ratio of 1:1.5~2.

[0014] Preferably, the antioxidant includes one or more of antioxidant 1010, antioxidant 1076, and antioxidant 168.

[0015] Preferably, the defoamer includes one or two of silicone defoamers and mineral oil defoamers.

[0016] The present invention also proposes a method for preparing crack-resistant hot-melt pavement marking paint, comprising the following steps: mixing the raw materials evenly to obtain the crack-resistant hot-melt pavement marking paint.

[0017] The working principle and beneficial effects of this invention are as follows: In this invention, the crack resistance of the hot-melt pavement marking paint is improved by selecting petroleum resin with a softening point of 91-95℃ and combining it with EVA hot-melt adhesive with a VA content of 32wt%-34wt% and a melt index of 350-450g / 10min. Specifically, the selected petroleum resin has a moderate softening point, maintaining good fluidity and adhesion at the construction temperature, while forming a well-compatible system with the EVA hot-melt adhesive. The high VA content in the EVA hot-melt adhesive imparts excellent flexibility and low-temperature toughness to the system, while the high melt index ensures excellent flow and penetration in the hot-melt state, fully wetting the filler and substrate surface and reducing internal stress concentration. The synergistic effect of the two enhances the deformation adaptability of the coating film under external stresses such as temperature cycling and load impact, thereby effectively inhibiting the generation and propagation of microcracks caused by substrate shrinkage, thermal stress, or vibration, and achieving improved crack resistance. Detailed Implementation

[0018] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will be described through embodiments.

[0020] A specific embodiment of the first aspect of the present invention provides a crack-resistant hot-melt pavement marking paint, comprising the following raw materials in parts by weight: 10-30 parts petroleum resin, 45-60 parts filler, 5-8 parts EVA hot melt adhesive, 2-4 parts plasticizer, 18-22 parts glass microspheres, 2-3 parts pigment, and 1.5-3 parts additives. The softening point of the petroleum resin is 91-95℃, the VA content of the EVA hot melt adhesive is 32wt%-34wt%, and the melt index of the EVA hot melt adhesive is 350-450g / 10min.

[0021] In this invention, the softening point of the petroleum resin is 91~95℃. This softening point range ensures that the coating can fully melt at the construction temperature and has good fluidity, making it easy to apply and form a tight bond with the road surface. It also ensures that the coating has suitable hardness and rigidity after cooling and curing, which can resist the shear force generated by vehicle rolling. This avoids the problems of the coating being easily deformed at high temperatures and producing plastic cracks due to the resin softening point being too low, or the coating being too brittle and easily cracking at low temperatures due to the softening point being too high. This lays the foundation for the crack resistance of the coating.

[0022] In this invention, the VA content of the EVA hot melt adhesive is 32wt%~34wt%, and the melt index is 350~450g / 10min. EVA hot melt adhesives within this parameter range have excellent flexibility, compatibility, and flowability. When the VA content is within this range, the polar groups of the EVA hot melt adhesive can form a good interaction with the molecular structure of petroleum resin, improving their compatibility and avoiding uneven internal structure of the coating due to component separation, which in turn causes internal stress and cracks. The limited melt index ensures that the EVA hot melt adhesive can quickly and uniformly mix with petroleum resin, fillers, and other components at the construction temperature, forming a continuous flexible network structure inside the coating. This effectively buffers the stress impact caused by temperature changes, road shrinkage, or vehicle rolling, and provides good crack resistance.

[0023] In one embodiment of the present invention, the filler is composed of first heavy calcium carbonate, second heavy calcium carbonate, flake talc and barium sulfate in a mass ratio of 40:10:5 to 8:4, wherein the first heavy calcium carbonate and the second heavy calcium carbonate have different particle sizes.

[0024] In this invention, heavy calcium carbonate constitutes the largest proportion of the filler. Combined with flaky talc, it can be uniformly dispersed within the coating, interpenetrating and tightly adhering to the heavy calcium carbonate particles. This enhances the overall integrity of the filler system, reduces relative sliding between particles, improves the coating's shear resistance, and thus helps improve compressive strength. Furthermore, the layered structure of the flaky talc forms a barrier within the coating, dispersing pressure transmission paths when the coating is subjected to pressure such as from vehicle traffic, preventing excessive local pressure that could lead to coating damage and cracking, further optimizing compressive strength. Simultaneously, the addition of flaky talc improves the coating's flowability, ensuring uniform dispersion of the filler in the molten coating and preventing localized structural loosening due to filler agglomeration, thus guaranteeing the uniformity of the overall compressive strength of the coating. Barium sulfate, with its high hardness and good chemical stability, synergistically enhances the effects of heavy calcium carbonate and flaky talc. Barium sulfate particles can fill the tiny gaps between the components, further reducing the coating's internal porosity and improving its density; simultaneously, its high hardness enhances the coating's compressive strength.

[0025] In one embodiment of the present invention, the particle size of the first heavy calcium carbonate is 400-425 mesh, the particle size of the second heavy calcium carbonate is 250-300 mesh, the particle size of the flake talc is 800-1000 mesh, and the particle size of the barium sulfate is 1250-1500 mesh.

[0026] In this invention, 400-425 mesh first heavy calcium carbonate is used as the main filler. The particle size is uniform and fine, which can be evenly dispersed in the bonding system to build a dense and rigid support skeleton. Compared with coarse-particle heavy calcium carbonate, it has a larger contact area with petroleum resin and EVA hot melt adhesive, and the bonding is tighter. It can effectively improve the overall load-bearing capacity of the coating and resist the deformation caused by external extrusion. The 250-300 mesh second heavy calcium carbonate can fill the gaps between the first heavy calcium carbonate particles, filling the tiny voids formed by the initial packing, initially reducing the internal porosity of the coating, reducing stress concentration points, and laying the foundation for subsequent finer filling. At the same time, it further enhances the rigidity of the filler system and helps improve the compressive strength of the coating. The 800-1000 mesh flake talc particles are extremely fine and can easily fill the tiny gaps between the first and second heavy calcium carbonate particles, further compressing the internal voids of the coating and improving the density of the structure. Its particle size is set at 1250-1500 mesh. As the finest component in the filler system, it plays a core role in fine filling and strengthening rigidity. Together with the first three components, it forms a complete multi-level particle size distribution system, minimizing the internal porosity of the coating, so that the filler system and the bonding system form a dense overall structure, fundamentally reducing stress concentration caused by internal voids, and significantly improving the compressive strength of the coating.

[0027] In one embodiment of the present invention, the glass microspheres have a particle size of 80-100 mesh.

[0028] In this invention, glass microspheres are the core material for ensuring the reflective performance of road markings. With a particle size of 80-100 mesh, they can form a reasonable raised structure on the coating surface. After cooling and solidification, they are firmly embedded in the coating, ensuring that the markings have a good reflective effect and guaranteeing driving safety. At the same time, they work synergistically with the multi-level particle size distribution of the filler system to help improve the compressive strength of the coating. The 80-100 mesh particle size is suitable for the coating application process and can be evenly dispersed during melt application, avoiding uneven coating surface and poor bonding with the adhesive system due to excessively large particle size, or loss of rigid support due to excessively small particle size.

[0029] In one embodiment of the present invention, the plasticizer includes one or more of dioctyl terephthalate, trioctyl trimellitate, and diisononyl phthalate, preferably dioctyl terephthalate.

[0030] In this invention, the plasticizer can penetrate between the molecular chains of petroleum resin and EVA hot melt adhesive, weaken the intermolecular forces, reduce the viscosity of the coating in the molten state, and make the coating have better fluidity and coating properties, making it easier to apply evenly to the road surface and avoiding problems such as uneven application and uneven coating surface caused by excessively high coating viscosity.

[0031] In one embodiment of the present invention, the pigment is rutile titanium dioxide.

[0032] In this invention, pigments impart a specific color to the coating and ensure clear visibility, meeting the warning and guidance needs of road traffic markings, and enhancing the contrast between the markings and the road surface. Whether under strong sunlight during the day or in low light conditions at night, drivers can quickly identify traffic markings such as lanes, zebra crossings, and parking spaces, clearly understand the traffic guidance, and reduce traffic accidents. This is the basic premise for road markings to function effectively.

[0033] In one embodiment of the present invention, the additive consists of an antioxidant and an antifoaming agent in a mass ratio of 1:1.5~2.

[0034] In one embodiment of the present invention, the antioxidant includes one or more of antioxidant 1010, antioxidant 1076, and antioxidant 168, preferably antioxidant 1010.

[0035] In this invention, antioxidants can inhibit thermal oxidative aging during the coating melting process, ensure coating processing quality, delay oxidative aging during coating service, and extend coating service life.

[0036] In one embodiment of the present invention, the defoamer includes one or two of silicone defoamers and mineral oil defoamers, preferably silicone defoamers.

[0037] In this invention, the defoamer can quickly penetrate to the surface of the bubbles, destroy the surface tension of the bubbles, cause the bubbles to burst and escape, and at the same time inhibit the generation of new bubbles, ensuring that the coating remains bubble-free throughout the melting, stirring and coating process, and ensuring that the coating has a smooth surface and dense interior after forming.

[0038] A specific embodiment of the second aspect of the present invention provides a method for preparing crack-resistant hot-melt pavement marking paint, comprising the following steps: mixing raw materials evenly to obtain crack-resistant hot-melt pavement marking paint.

[0039] The present invention will now be described in detail with reference to preferred embodiments and comparative examples. The preferred embodiments of the invention described below can be modified in various ways, and therefore the scope of the invention should not be construed as limited to the preferred embodiments described in detail below. Preferred embodiments are provided to help those skilled in the art to more readily understand the invention.

[0040] Unless otherwise specified, the following embodiments and comparative examples are as follows: Petroleum resin: C5 hydrocarbon resin, softening point 91℃, type 7590; EVA hot melt adhesive: VA content is 32wt%~34wt%, melt index is 350~450g / 10min, model is EVA 33-400; First-grade calcium carbonate: average particle size is 425 mesh; Secondary calcium carbonate: average particle size is 300 mesh; Flaky talc: average particle size is 800 mesh; Barium sulfate: average particle size is 1250 mesh; Glass microspheres: average particle size is 80 mesh; Organosilicon defoamer: Model number BYK-066N.

[0041] Example 1 A crack-resistant hot-melt pavement marking paint comprises the following raw materials in parts by weight: 15 parts petroleum resin, 45 parts filler, 5 parts EVA hot melt adhesive, 2 parts dioctyl terephthalate, 18 parts glass microspheres, 2 parts rutile titanium dioxide, and 1.5 parts additives. The additives consist of antioxidant 1010 and silicone defoamer in a mass ratio of 1:1.5; The filler is composed of first-weight calcium carbonate and talc in a mass ratio of 40:5; A method for preparing a crack-resistant hot-melt pavement marking paint includes the following steps: mixing raw materials evenly to obtain a crack-resistant hot-melt pavement marking paint.

[0042] Example 2 A crack-resistant hot-melt pavement marking paint comprises the following raw materials in parts by weight: 20 parts petroleum resin, 50 parts filler, 6 parts EVA hot melt adhesive, 3 parts dioctyl terephthalate, 20 parts glass microspheres, 2.5 parts rutile titanium dioxide, and 2 parts additives. The additives consist of antioxidant 1010 and silicone defoamer in a mass ratio of 1:1.5; The filler is composed of first-weight calcium carbonate and talc in a mass ratio of 40:5; A method for preparing a crack-resistant hot-melt pavement marking paint includes the following steps: mixing raw materials evenly to obtain a crack-resistant hot-melt pavement marking paint.

[0043] Example 3 A crack-resistant hot-melt pavement marking paint comprises the following raw materials in parts by weight: 30 parts petroleum resin, 60 parts filler, 8 parts EVA hot melt adhesive, 4 parts dioctyl terephthalate, 22 parts glass microspheres, 3 parts rutile titanium dioxide, and 3 parts additives. The additives consist of antioxidant 1010 and silicone defoamer in a mass ratio of 1:2; The filler is composed of first-weight calcium carbonate and talc in a mass ratio of 40:5; A method for preparing a crack-resistant hot-melt pavement marking paint includes the following steps: mixing raw materials evenly to obtain a crack-resistant hot-melt pavement marking paint.

[0044] Example 4 Compared with Example 2, Example 4 differs in that the petroleum resin (C5 hydrocarbon resin, softening point 91°C, type 7590) is replaced with an equal amount of petroleum resin, C5 hydrocarbon resin, softening point 95°C, type 8595.

[0045] Example 5 The difference between Example 5 and Example 2 is that the filler is composed of first heavy calcium carbonate and second heavy calcium carbonate in a mass ratio of 40:10.

[0046] Example 6 The difference between Example 6 and Example 2 is that the filler is composed of first heavy calcium carbonate, second heavy calcium carbonate and flaky talc powder in a mass ratio of 40:10:5.

[0047] Example 7 The difference between Example 7 and Example 2 is that the filler is composed of first heavy calcium carbonate, second heavy calcium carbonate, flake talc and barium sulfate in a mass ratio of 40:10:5:4.

[0048] Example 8 The difference between Example 8 and Example 7 is that the filler is composed of first heavy calcium carbonate, second heavy calcium carbonate, flake talc and barium sulfate in a mass ratio of 40:10:8:4.

[0049] Example 9 The difference between Example 9 and Example 8 is that the first heavy calcium carbonate is replaced with an equal amount of heavy calcium carbonate with an average particle size of 800 mesh.

[0050] Example 10 The difference between Example 10 and Example 8 is that the flake talc powder is replaced with an equal amount of flake talc powder with a particle size of 6000 mesh.

[0051] Comparative Example 1 Compared with Example 2, Comparative Example 1 differs in that the petroleum resin (C5 hydrocarbon resin, softening point 91°C, type 7590) is replaced with an equal amount of petroleum resin, C5 hydrocarbon resin, softening point 50°C, type 7050.

[0052] Comparative Example 2 Compared with Example 2, Comparative Example 2 differs in that the petroleum resin (C5 hydrocarbon resin, softening point 91°C, type 7590) is replaced with an equal amount of petroleum resin, C5 hydrocarbon resin, softening point 112°C, type 1115.

[0053] Comparative Example 3 Compared with Example 2, Comparative Example 3 differs in that the EVA hot melt adhesive (VA content of 32wt%~34wt%, melt index of 350~450g / 10min, model EVA 33-400) was replaced with an equal amount of EVA hot melt adhesive with VA content of 17wt%~19wt%, melt index of 135~175g / 10min, model EVA 18-150.

[0054] Comparative Example 4 Compared with Example 2, Comparative Example 4 differs in that the EVA hot melt adhesive (VA content of 32wt%~34wt%, melt index of 350~450g / 10min, model EVA 33-400) was replaced with an equal amount of EVA hot melt adhesive with VA content of 30wt%~32wt%, melt index of 700~900g / 10min, model EVA 28-800.

[0055] Experimental Example 1 The hot-melt road marking paints prepared in Examples 1-4 and Comparative Examples 1-4 were melt-sprayed onto cement asbestos boards (spray thickness 2 mm), according to JT / T 280. The 2022 standard for road marking paints specifies the low-temperature crack resistance test, with the following evaluation criteria: Keep at 10℃ for 4 hours, then leave at room temperature for 4 hours as one cycle. After performing 4 cycles, determine whether there are cracks.

[0056] The results of the low-temperature crack resistance test are shown in Table 1: Table 1 Performance test results of Examples 1-4 and Comparative Examples 1-4

[0057] As shown in Table 1, when the softening point of petroleum resin in the raw materials of hot melt pavement marking paint is 91~95℃, and the VA content of EVA hot melt adhesive is 32wt%~34wt%, and the melt index is 350~450g / 10min, the crack resistance of hot melt pavement marking paint can be improved.

[0058] Experimental Example 2 The hot-melt road marking paints prepared in Examples 2 and 5-10 were melt-sprayed onto cement asbestos boards (spray thickness 2 mm), according to JT / T 280. The compressive strength of the 2022 "Road Marking Paint" was determined at a temperature of 23℃.

[0059] The test results are shown in Table 2: Table 2 Performance test results of Examples 2 and 5-10

[0060] As shown in Table 2, when the filler is composed of primary heavy calcium carbonate, secondary heavy calcium carbonate, flake talc, and barium sulfate, the compressive strength of the hot-melt pavement marking paint can be improved. When the particle size of the primary heavy calcium carbonate is 400-425 mesh, the particle size of the secondary heavy calcium carbonate is 250-300 mesh, the particle size of the flake talc is 800-1000 mesh, and the particle size of the barium sulfate is 1250-1500 mesh, the gradation relationship formed by the components can further improve the compressive strength of the hot-melt pavement marking paint.

[0061] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An anti-cracking hot melt pavement marking coating, characterized by, The raw materials include the following components by weight: 10-30 parts petroleum resin, 45-60 parts filler, 5-8 parts EVA hot melt adhesive, 2-4 parts plasticizer, 18-22 parts glass microspheres, 2-3 parts pigment, and 1.5-3 parts additives. The softening point of the petroleum resin is 91-95℃, the VA content of the EVA hot melt adhesive is 32wt%-34wt%, and the melt index of the EVA hot melt adhesive is 350-450g / 10min.

2. The anti-cracking hot melt pavement marking coating according to claim 1, characterized in that, The filler is composed of first heavy calcium carbonate, second heavy calcium carbonate, flaky talc, and barium sulfate in a mass ratio of 40:10:5 to 8:4, wherein the first heavy calcium carbonate and the second heavy calcium carbonate have different particle sizes.

3. The anti-cracking hot melt pavement marking coating according to claim 2, characterized in that, The first heavy calcium carbonate has a particle size of 400-425 mesh, the second heavy calcium carbonate has a particle size of 250-300 mesh, the flaky talc has a particle size of 800-1000 mesh, and the barium sulfate has a particle size of 1250-1500 mesh.

4. The anti-cracking hot melt pavement marking coating according to claim 1, characterized in that, The glass microspheres have a particle size of 80-100 mesh.

5. The anti-cracking hot melt pavement marking coating according to claim 1, characterized in that, The plasticizer includes one or more of dioctyl terephthalate, trioctyl trimellitate, and diisononyl phthalate.

6. The anti-cracking hot melt pavement marking coating according to claim 1, characterized in that, The pigment is rutile titanium dioxide.

7. The anti-cracking hot melt pavement marking coating according to claim 1, characterized in that, The additive consists of an antioxidant and an antifoaming agent in a mass ratio of 1:1.5~2.

8. The anti-cracking hot melt pavement marking coating according to claim 7, characterized in that, The antioxidant includes one or more of antioxidant 1010, antioxidant 1076, and antioxidant 168.

9. The anti-cracking hot melt pavement marking coating according to claim 7, characterized in that, The defoamer includes one or both of the following: silicone defoamer and mineral oil defoamer.

10. A method for preparing a hot melt pavement marking coating resistant to cracking, for preparing a hot melt pavement marking coating resistant to cracking according to any one of claims 1 to 9, characterized in that, Includes the following steps: The raw materials are mixed evenly to obtain the crack-resistant hot-melt pavement marking paint.

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