Multi-layer surface moisture-proof protection method for salt-based building decoration material and multi-layer composite protection coating
By using a multi-layered composite protective coating, alternating inorganic densification layers and organic-inorganic hybrid hydrophobic layers are constructed to solve the moisture-proof problem of salt-based materials in high-humidity environments, extend their lifespan and maintain their appearance, and make them suitable for a variety of salt-based building and decorative materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YAOSHAN LABORATORY
- Filing Date
- 2026-02-11
- Publication Date
- 2026-05-12
AI Technical Summary
Existing salt-based building decoration materials are prone to moisture absorption in high humidity environments, leading to structural deterioration. Current moisture-proof technologies cannot simultaneously achieve internal ion migration blocking and efficient surface hydrophobic protection, affecting the material's lifespan and appearance.
A multi-layer composite protective coating is adopted, which alternately constructs an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer to form structures such as AB and ABAB. The phosphorus-silicon cross-linking network and long-chain alkylsilanes are used to form a continuous and dense barrier to enhance the moisture-proof performance.
It significantly improves the corrosion resistance of salt-based materials in high humidity environments, extends their service life, maintains the appearance and texture of the materials, and is suitable for a variety of salt-based building and decorative materials, thus broadening the application scenarios.
Smart Images
Figure CN122006989A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of building and decorative material protection, and particularly relates to a salt-based protective coating for building and decorative materials. Background Technology
[0002] Salt-based building materials, with their unique crystalline structure and natural texture, possess irreplaceable application value in fields such as salt sculpture art creation, salt brick wall construction, and mineral salt decorative panel decoration, becoming one of the distinctive materials in the fields of architectural decoration and art design. However, the presence of a large number of hydrophilic ions in their crystalline structure makes them extremely sensitive to environmental humidity. In high humidity environments, the material easily absorbs moisture rapidly, triggering a dissolution reaction, which in turn leads to structural deterioration. This easily causes surface weathering and peeling, a loose internal structure leading to a significant reduction in strength, and damage to the appearance, color, and shape. This not only greatly shortens the service life of salt-based products but also seriously damages their core decorative and artistic value, becoming a core bottleneck restricting the large-scale promotion of this type of material in the field of architectural decoration.
[0003] To address the moisture-proofing requirements of salt-based materials, existing research has primarily yielded two solutions: The first is surface coating-based moisture-proofing, which creates a physical barrier by constructing a hydrophobic coating on the material surface, preventing contact between external moisture and the hydrophilic ions within the material. However, this technology has significant limitations. To achieve stable moisture-proofing, a relatively thick coating structure is required, which is prone to peeling and cracking due to the difference in thermal expansion coefficients between the coating and the substrate. Furthermore, it completely obscures the unique natural texture and feel of salt-based materials, negating their core application advantages. The second is internal doping-based moisture-proofing, which adds hydrophobic fillers to the raw materials of salt-based materials, utilizing the filler's hydrophobic properties to slow down the diffusion rate of moisture within the material. However, this technology is limited by the uniform dispersion of the filler in the matrix, making it difficult to form a continuous and dense hydrophobic barrier network. This results in limited improvement in moisture-proofing performance, especially under harsh environments such as high temperature and high humidity, where the moisture-proofing effect deteriorates rapidly as the interfacial bonding between the filler and the substrate weakens. In summary, existing moisture-proof technologies have significant shortcomings in the three core indicators of durability, appearance retention, and process stability, and cannot meet the requirements of long-term moisture-proof performance of salt-based materials in practical application scenarios.
[0004] Therefore, the key area for breakthrough in the current field of moisture-proof technology for salt-based materials lies in developing an integrated moisture-proof solution that can simultaneously achieve "internal ion migration barrier" and "efficient surface hydrophobic protection." This requires constructing a stable and long-lasting moisture-proof structure without compromising the natural texture and smooth appearance of the salt-based materials. This will ensure the reliability of the materials during long-term service in high-humidity environments and provide technical support for the widespread application of salt-based materials in architectural decoration and art. Summary of the Invention
[0005] To address the technical problem of poor long-term moisture resistance of salt-based materials, this invention proposes a multi-layer surface moisture-proof protection method and a multi-layer composite protective coating for salt-based building decoration materials. By alternately constructing an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer, a multi-layer structure such as AB and ABAB is formed, significantly improving the service life of the material in environments such as humidity, salt spray, and thermal cycling. To achieve the above objectives, this invention provides the following technical solution:
[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:
[0007] A multi-layer surface moisture-proof protection method for salt-based building decoration materials, comprising alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer on the surface of a salt-based substrate, including the following steps:
[0008] (1) Inorganic densification layer: Phosphosilicate sol coated on the surface of a base matrix is cured to form a continuous inorganic network structure;
[0009] (2) Organic-inorganic hybrid hydrophobic layer: A silica sol containing long-chain alkyl silane end-capping agents is coated on the surface of the inorganic densification layer and cured to obtain an organic-inorganic hybrid hydrophobic layer.
[0010] The preparation method of the phosphorus silica sol in step (1) is as follows: mix tetraalkoxysilane, phosphorus ester and solvent I to obtain phosphorus silica mixture; then add acid solution I to adjust the pH to 4-6 and perform hydrolysis and aging to obtain phosphorus silica sol containing PO-Si network structure.
[0011] The tetraalkoxysilane is any one or more of tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane; the phosphorus ester is a phosphate ester or a phosphite ester, and the phosphate ester is any one or more of trimethyl phosphate, triethyl phosphate, and tributyl phosphate.
[0012] Solvent I is any one or more of water, methanol, ethanol, isopropanol, and n-butanol; acid I is any one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, and citric acid.
[0013] The mass ratio of the tetraalkoxysilane to the phosphorus ester is 1-20:1, and the concentration of the tetraalkoxysilane in the phosphorus-silicon mixture is 0.05-0.5 g / mL.
[0014] The method for preparing the silica sol containing long-chain alkylsilane end-capping agent is as follows: silane is dissolved in solvent II to obtain a silane solution, then acid II is added to adjust the pH to 4-6 and hydrolysis aging is performed, and finally long-chain alkylsilane end-capping agent is added and mixed evenly to obtain silica sol containing long-chain alkylsilane end-capping agent.
[0015] The silane is tetraalkoxysilane, or any one or more of tetraalkoxysilane, methyltriethoxysilane, and phenyltriethoxysilane; the long-chain alkylsilane end-capping agent is any one or more of octyltrimethoxysilane, octyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethoxysilane, octyltrichlorosilane, octadecyltrichlorosilane, and octadecyldimethylchlorosilane.
[0016] The solvent II is any one or more of water, methanol, ethanol, isopropanol and n-butanol; the acid II is any one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid and citric acid.
[0017] The concentration of the silane solution is 0.05-0.5 g / mL; the mass ratio of the silane to the long-chain alkylsilane end-capping agent is 1:0.01-0.1.
[0018] Preferably, acid solution I and acid solution II are added dropwise, and the mixture is stirred for 30-60 minutes after the addition is completed.
[0019] Preferably, in the preparation of the phosphosilicate sol and the silica sol containing long-chain alkylsilane end-capping agents, hydrolysis aging is carried out at room temperature for 1-3 hours.
[0020] Preferably, in the preparation of the inorganic densification layer and the organic-inorganic hybrid hydrophobic layer, the curing temperature is 70-90℃ and the time is 1-3 hours. The coating is applied by spraying or dipping, and can be repeated multiple times. After each coating, curing and drying are performed before applying the next layer.
[0021] A multi-layer composite protective coating for the surface of a salt-based building decoration material includes an inorganic densifying layer and an organic-inorganic hybrid hydrophobic layer alternately constructed on the surface of a salt-based substrate. The inorganic densifying layer is located in the innermost layer, and the organic-inorganic hybrid hydrophobic layer is located in the outermost layer. The thickness of the inorganic densifying layer is 1-10 μm, and the thickness of the organic-inorganic hybrid hydrophobic layer is 1-10 μm.
[0022] The beneficial effects of this invention are:
[0023] (1) This invention can flexibly construct composite protective structures such as AB and ABAB by alternating deposition of inorganic densification layers and organic-inorganic hybrid hydrophobic layers. This multi-layer synergistic design can effectively alleviate the interface stress difference between the coating and the base substrate, avoid cracking and peeling caused by the mismatch of thermal expansion coefficients, and form "multiple physical barriers", which significantly enhances the barrier continuity and the overall service stability of the coating, and solves the defects of the prior art in process stability.
[0024] (2) Relying on the unique phosphorus-silicon cross-linked network structure of the inorganic densification layer, its densification can significantly reduce the outward migration rate of hydrophilic ions inside the salt-based material, thereby reducing the contact reaction between water and ions from the source and enhancing the moisture-proof performance from the perspective of "anti-ion migration". Compared with the limitation of existing internal doping technology, which can only delay the diffusion of moisture, this solution achieves the dual function of "ion barrier + moisture protection", significantly improving the corrosion resistance of salt-based materials in high humidity environments and effectively extending the service life of products.
[0025] (3) The organic-inorganic hybrid hydrophobic layer not only provides superhydrophobic properties with a contact angle of over 125°, which can quickly repel external moisture and prevent the material surface from absorbing moisture; it also has excellent anti-ultraviolet aging properties and can resist the degradation effect of outdoor ultraviolet rays on the protective layer. This design not only solves the problem of existing thick coatings covering the natural texture of salt-based materials (high-efficiency protection can be achieved without thick coating, and the original texture of the material can be preserved), but also breaks through the bottleneck of traditional moisture-proof technology being prone to failure in harsh outdoor environments, achieving dual protection of "appearance retention" and "weather resistance", meeting the long-term protection needs of different indoor and outdoor scenarios.
[0026] (4) The moisture-proof treatment method of the present invention does not require adjustment of the core process for specific salt-based products. It can be widely applied to various salt-based building and decorative materials such as salt boards, salt bricks, salt sculptures, and salt curtain walls. Moreover, it can optimize the protective effect by adjusting the composite layer structure (such as AB, ABAB, etc.) according to the different environmental requirements such as humidity and ultraviolet intensity in indoor (e.g., home salt decorative walls) and outdoor (e.g., salt-material landscape sculptures, salt curtain walls). Compared with the problem of limited adaptability of existing technologies, this solution greatly expands the application scenarios of salt-based materials and provides key technical support for their large-scale promotion in the fields of architectural decoration and art. Attached Figure Description
[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0028] Figure 1 The water contact angle of each embodiment and comparative sample was measured;
[0029] Figure 2 Infrared spectra of the inorganic densification layer;
[0030] Figure 3 Infrared spectra of organic-inorganic hybrid hydrophobic layers;
[0031] Figure 4A planar image of a double-coated layer under a scanning electron microscope;
[0032] Figure 5 The surface changes of the salt plate treated in Example 1 after being placed under 80% RH conditions for 30 days. Detailed Implementation
[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0034] Example 1
[0035] A multi-layer surface moisture-proof protection method for salt-based building decoration materials, comprising alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer on the surface of a salt-based substrate, including the following steps:
[0036] (1) Take a 200 mm * 100 mm * 10 mm salt plate as the substrate;
[0037] (2) Preparation of inorganic densification layer: Mix 70 mL ethanol, 8 g TEOS and 1 g TEP; slowly add acetic acid, adjust the pH of the solution to 4-5, stir for 1 h, age for 1 h, spray 3 times, dry at 50 ℃ for 30 min each time, and finally cure at 80 ℃ for 2 h.
[0038] (3) Preparation of organic-inorganic hybrid hydrophobic layer: Mix 70 mL of ethanol, 6 g of TEOS and 6 g of MTES, add acetic acid solution to adjust the pH of the solution to 4-5, stir for 45 min, and add 0.5 g of C 12 -TEOS, after stirring for 15 min, spray 3 times, each time drying at 60 ℃ for 30 min, and finally curing at 80 ℃ for 2 h.
[0039] Figure 2 and 3 The infrared spectra of the inorganic densified layer and the organic-inorganic hybrid hydrophobic layer in steps (2) and (3) above are respectively, provided by... Figure 2 After aging for 1 hour, the inorganic densification layer solution exhibited a significant P–O–Si absorption peak in the infrared spectrum, indicating that the phosphorus source and TEOS had undergone a co-hydrolysis-condensation reaction, forming a stable phosphorus-silicon-oxygen bridging structure (P–O–Si). This signifies the evolution of the sol system from simple molecular mixing to an inorganic cross-linked network, forming a highly dense inorganic barrier layer with low ion mobility. Figure 3It can be seen that after aging the organic-inorganic hybrid hydrophobic layer solution for 1 h, a significant Si–O–Si absorption peak appears, indicating that the silane precursor has undergone effective hydrolysis and condensation reaction and has begun to form a continuous silicon-oxygen framework network.
[0040] Figure 4 The surface morphology after coating with an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer is shown. After spraying, the microstructure of the salt board surface did not change significantly, indicating that the moisture-proof coating is an ultra-thin and dense layer, which can improve the moisture-proof performance without changing the surface morphology and texture of the substrate.
[0041] Depend on Figure 1 and Figure 5 It can be seen that after treatment in Example 1, the contact angle of the salt plate surface reached 121°, and after being placed at 30 ℃ and 80%RH for 30 days, there was no obvious powdering on the surface.
[0042] Example 2
[0043] A multi-layer surface moisture-proof protection method for salt-based building decoration materials, comprising alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer on the surface of a salt-based substrate, including the following steps:
[0044] (1) Take a 200 mm × 100 mm × 10 mm salt board as the substrate;
[0045] (2) Preparation of inorganic densification layer: 70 mL methanol, 10 g TMOS (tetramethoxysilane) and 0.5 g TMP (trimethyl phosphate) were mixed (TMOS:TMP mass ratio 20:1); hydrochloric acid was slowly added dropwise to adjust the pH of the solution to 4-5, stirred for 1.5 h, aged for 2 h, dip-coated twice, dried at 40 ℃ for 45 min each time, and finally cured at 70 ℃ for 3 h;
[0046] (3) Preparation of organic-inorganic hybrid hydrophobic layer: 70 mL isopropanol, 5 g TMOS and 7 g PTES (phenyltriethoxysilane) were mixed, 10 mL water and 0.4 mL nitric acid solution (0.05 mol / L) were added dropwise, and the mixture was stirred for 60 min. Then 0.3 g C8-TMOS (octyltrimethoxysilane) was added, and the mixture was stirred for 20 min. After stirring, the mixture was sprayed 4 times, and each time it was dried at 55 ℃ for 25 min. Finally, it was cured at 85 ℃ for 1.5 h.
[0047] Depend on Figure 1 It can be seen that after treatment in Example 2, the contact angle of the salt plate surface reached 123°, and after being placed at 30 ℃ and 80%RH for 30 days, there was no obvious powdering on the surface.
[0048] Example 3
[0049] A multi-layer surface moisture-proof protection method for salt-based building decoration materials, comprising alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer on the surface of a salt-based substrate, including the following steps:
[0050] (1) Take a 200 mm × 100 mm × 10 mm salt board as the substrate;
[0051] (2) Preparation of inorganic densification layer: 80 mL of ethanol, 6 g of TEOS and 1.5 g of TBP (tributyl phosphate) were mixed (TEOS:TBP mass ratio 4:1); sulfuric acid (0.01 mol / L) was slowly added dropwise to adjust the pH of the solution to 4-5, stirred for 0.5 h, aged for 1.5 h, sprayed 4 times, dried at 60 ℃ for 20 min each time, and finally cured at 90 ℃ for 1 h;
[0052] (3) Preparation of organic-inorganic hybrid hydrophobic layer: 60 mL n-butanol, 7 g TEOS and 5 g MTES were mixed, citric acid solution was added dropwise to adjust the pH of the solution to 4-5, and the mixture was stirred for 30 min. Then 0.7 g C18-TMOS (octadecyltrimethoxysilane) was added and stirred for 10 min. The mixture was then dip-coated 3 times, and each time it was dried at 65 ℃ for 40 min. Finally, it was cured at 75 ℃ for 2.5 h.
[0053] Depend on Figure 1 It can be seen that after treatment in Example 3, the contact angle of the salt plate surface reached 122°, and after being placed at 30 ℃ and 80%RH for 30 days, there was no obvious powdering on the surface.
[0054] Example 4
[0055] A multi-layer surface moisture-proof protection method for salt-based building decoration materials, comprising alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer (ABAB dual-layer structure) on the surface of a salt-based substrate, including the following steps:
[0056] (1) Take a 200 mm × 100 mm × 10 mm salt board as the substrate;
[0057] (2) Preparation of the first inorganic densification layer: 75 mL of ethanol, 9 g of TPOS (tetrapropoxysilane) and 1.2 g of phosphite were mixed (TPOS:phosphite mass ratio 7.5:1); acetic acid aqueous solution was slowly added dropwise to adjust the pH of the solution to 4-5, stirred for 1.2 h, aged for 1.2 h, sprayed twice, dried at 45 ℃ for 35 min each time, and finally cured at 80 ℃ for 2 h;
[0058] (3) Preparation of the first organic-inorganic hybrid hydrophobic layer: 70 mL of methanol, 4 g of TPOS and 8 g of MTES were mixed, hydrochloric acid solution was added dropwise to adjust the pH of the solution to 4-5, and the mixture was stirred for 50 min. Then, 0.4 g of C16-TES (hexadecyltriethoxysilane) was added and stirred for 18 min. The mixture was then sprayed three times, and each time it was dried at 58 °C for 28 min. Finally, it was cured at 82 °C for 1.8 h.
[0059] (4) Preparation of the second inorganic densification layer: 75 mL of ethanol, 6 g of TPOS (tetrapropoxysilane) and 1.2 g of phosphite were mixed; acetic acid aqueous solution was slowly added dropwise to adjust the pH of the solution to 4-5, stirred for 1.2 h, aged for 1.2 h, sprayed twice, dried at 45 ℃ for 35 min each time, and finally cured at 80 ℃ for 2 h.
[0060] (5) Preparation of the second organic-inorganic hybrid hydrophobic layer: Repeat step (3) to obtain the second organic-inorganic hybrid hydrophobic layer.
[0061] Depend on Figure 1 It can be seen that after treatment in Example 4, the contact angle of the salt plate surface reached 130°, and after being placed at 30 ℃ and 80%RH for 30 days, there was no obvious powdering on the surface.
[0062] Example 5
[0063] A multi-layer surface moisture-proof protection method for salt-based building decoration materials, comprising alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer on the surface of a salt-based substrate, including the following steps:
[0064] (1) Take a 200 mm × 100 mm × 10 mm salt board as the substrate;
[0065] (2) Preparation of inorganic densification layer: 65 mL of water / ethanol mixed solvent (volume ratio 1:1), 7 g of TBOS (tetrabutoxysilane) and 2 g of TEP were mixed (TBOS:TEP mass ratio 3.5:1); nitric acid (0.02 mol / L) aqueous solution was slowly added dropwise to adjust the pH of the solution to 4-5, stirred for 2 h, aged for 0.8 h, dip-coated 5 times, dried at 50 ℃ for 30 min each time, and finally cured at 85 ℃ for 2.5 h;
[0066] (3) Preparation of organic-inorganic hybrid hydrophobic layer: 75 mL isopropanol, 8 g TBOS and 4 g PTES were mixed, the pH of the solution was adjusted to 4-5 with sulfuric acid aqueous solution, stirred for 40 min, 0.6 g C12-TES was added, stirred for 25 min and then sprayed twice, each time dried at 70 ℃ for 20 min, and finally cured at 80 ℃ for 1 h.
[0067] Depend on Figure 1 It can be seen that after treatment in Example 5, the contact angle of the salt plate surface reached 124°, and after being placed at 30 ℃ and 80%RH for 30 days, there was no obvious powdering on the surface.
[0068] Example 6
[0069] A multi-layer surface moisture-proof protection method for salt-based building decoration materials, comprising alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer on the surface of a salt-based substrate, including the following steps:
[0070] (1) Take a 200 mm × 100 mm × 10 mm salt board as the substrate;
[0071] (2) Preparation of inorganic densification layer: Mix 70 mL of ethanol, 5 g of TEOS and 0.8 g of TMP (TEOS:TMP mass ratio 6.25:1); slowly add citric acid aqueous solution, adjust the pH of the solution to 4-5, stir for 1 h, age for 3 h, spray 3 times, dry at 55 ℃ for 40 min each time, and finally cure at 75 ℃ for 3 h;
[0072] (3) Preparation of organic-inorganic hybrid hydrophobic layer: 70 mL n-butanol, 6 g TEOS and 6 g MTES were mixed, and the pH of the solution was adjusted to 4-5 using acetic acid solution. After stirring for 55 min, 0.4 g C18-TClS (octadecyltrichlorosilane) was added and stirred for 12 min. The mixture was then dip-coated 4 times, and each time it was dried at 50 ℃ for 35 min. Finally, it was cured at 90 ℃ for 1.5 h.
[0073] Depend on Figure 1 It can be seen that after treatment in Example 5, the contact angle of the salt plate surface reached 127°, and after being placed at 30 ℃ and 80%RH for 30 days, there was no obvious powdering on the surface.
[0074] Example 7
[0075] A multi-layer surface moisture-proof protection method for salt-based building decoration materials, comprising alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer on the surface of a salt-based substrate, including the following steps:
[0076] (1) Take a 200 mm × 100 mm × 10 mm salt board as the substrate;
[0077] (2) Preparation of inorganic densification layer: 80 mL methanol, 12 g TMOS and 1.8 g TBP were mixed (TMOS:TBP mass ratio 6.67:1); sulfuric acid (0.05 mol / L) was slowly added dropwise to adjust the pH of the solution to 4-5, stirred for 1.5 h, aged for 1 h, sprayed once, dried at 60 ℃ for 25 min each time, and finally cured at 70 ℃ for 2 h.
[0078] (3) Preparation of organic-inorganic hybrid hydrophobic layer: 65 mL of ethanol, 5 g of TMOS and 9 g of PTES were mixed, 12 mL of water and 0.4 mL of nitric acid solution were added dropwise, and the mixture was stirred for 35 min. Then, 0.8 g of C8-TClS (octyltrichlorosilane) was added, and the mixture was stirred for 30 min. After that, the mixture was sprayed 5 times, and each time it was dried at 65 °C for 15 min. Finally, it was cured at 85 °C for 2 h.
[0079] Depend on Figure 1 It can be seen that after treatment in Example 7, the contact angle of the salt plate surface reached 124°, and after being placed at 30 ℃ and 80%RH for 30 days, there was no obvious powdering on the surface.
[0080] Comparative Example 1 (uncoated)
[0081] A 200 mm × 100 mm × 10 mm salt plate was used as the substrate. Without any treatment, the surface contact angle was directly measured to be 30°. Figure 1 After being placed at 30 ℃ and 80%RH for 30 days, the surface of the sample showed severe powdering.
[0082] Comparative Example 2 (only inorganic densification layer coated)
[0083] A 200 mm × 100 mm × 10 mm salt plate was used as the substrate. Only an inorganic densification layer was prepared: 70 mL of ethanol, 8 g of TEOS, and 1 g of TEP were mixed; 10 mL of deionized water and 0.3 mL of acetic acid were mixed and slowly added dropwise, stirred for 1 h, aged for 1 h, sprayed three times, and dried at 50 ℃ for 30 min each time, and finally cured at 80 ℃ for 2 h. No organic-inorganic hybrid hydrophobic layer was coated.
[0084] Depend on Figure 1 It can be seen that after treatment with Comparative Example 2, the contact angle of the salt plate surface reached 60°, and after being placed at 30 ℃ and 80%RH for 30 days, the surface showed powdering.
[0085] Comparative Example 3 (only coated with organic-inorganic hybrid hydrophobic layer)
[0086] A 200 mm × 100 mm × 10 mm salt plate was used as the substrate. Only an organic-inorganic hybrid hydrophobic layer was prepared: 70 mL of ethanol, 6 g of TEOS, and 6 g of MTES were mixed, and acetic acid solution was added dropwise to adjust the pH of the solution to 4-5. The mixture was stirred for 45 min, and then 0.5 g of C12-TEOS was added. After stirring for 15 min, the mixture was sprayed three times, each time drying at 60 ℃ for 30 min, and finally cured at 80 ℃ for 2 h. No inorganic densification layer was applied.
[0087] Depend on Figure 1 It can be seen that after treatment with Comparative Example 3, the contact angle of the salt plate surface reached 62°. After being placed at 30 ℃ and 80%RH for 30 days, obvious traces of ion migration and powdering appeared on the surface.
[0088] The above description is only a preferred embodiment of the present invention and is 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. A method for multi-layer surface moisture protection of salt-based building decoration materials, characterized in that, Alternating coating of an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer on the surface of a basic substrate includes the following steps: (1) Inorganic densification layer: Phosphosilicate sol coated on the surface of a base matrix is cured to form a continuous inorganic network structure; (2) Organic-inorganic hybrid hydrophobic layer: A silica sol containing long-chain alkyl silane end-capping agents is coated on the surface of the inorganic densification layer and cured to obtain an organic-inorganic hybrid hydrophobic layer.
2. The method for multi-layer surface moisture protection of salt-based building decoration materials according to claim 1, characterized in that, The preparation method of the phosphorosilicate sol in step (1) is as follows: a phosphorosilicate mixture is obtained by mixing tetraalkoxysilane, phosphorus ester and solvent I; then acid solution I is added to adjust the pH and hydrolysis and aging are carried out to obtain phosphorosilicate sol containing PO-Si network structure.
3. The method for multi-layer surface moisture protection of salt-based building decoration materials according to claim 2, characterized in that, The tetraalkoxysilane is any one or more of tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, and tetrabutoxysilane; the phosphorus ester is a phosphate ester or a phosphite ester, and the phosphate ester is any one or more of trimethyl phosphate, triethyl phosphate, and tributyl phosphate.
4. The method for multi-layer surface moisture protection of salt-based building decoration materials according to claim 3, characterized in that, Solvent I is any one or more of water, methanol, ethanol, isopropanol, and n-butanol; acid I is any one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, and citric acid.
5. The method for multi-layer surface moisture protection of salt-based building decoration materials according to claim 4, characterized in that, The mass ratio of the tetraalkoxysilane to the phosphorus ester is 1-20:1, and the concentration of the tetraalkoxysilane in the phosphorus-silicon mixture is 0.05-0.5 g / mL; in step (1), acid solution I is added to adjust the pH to 4-6.
6. The method for multi-layer surface moisture protection of salt-based building decoration materials according to any one of claims 1-5, characterized in that, The preparation method of the silica sol containing long-chain alkylsilane end-capping agent in step (2) is as follows: silane is dissolved in solvent II to obtain a silane solution, then acid solution II is added to adjust the pH and hydrolyze and age it, and finally long-chain alkylsilane end-capping agent is added and mixed evenly to obtain silica sol containing long-chain alkylsilane end-capping agent.
7. The method for multi-layer surface moisture protection of salt-based building decoration materials according to claim 6, characterized in that, The silane is tetraalkoxysilane, or any one or more of tetraalkoxysilane, methyltriethoxysilane, and phenyltriethoxysilane; the long-chain alkylsilane end-capping agent is any one or more of octyltrimethoxysilane, octyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethoxysilane, octyltrichlorosilane, octadecyltrichlorosilane, and octadecyldimethylchlorosilane.
8. The method for multi-layer surface moisture protection of salt-based building decoration materials according to claim 7, characterized in that, The solvent II is any one or more of water, methanol, ethanol, isopropanol and n-butanol; the acid II is any one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid and citric acid.
9. The method for multi-layer surface moisture protection of salt-based building decoration materials according to claim 8, characterized in that, The concentration of the silane solution is 0.05-0.5 g / mL; the mass ratio of the silane to the long-chain alkylsilane end-capping agent is 1:0.01-0.1; acid solution II is added in step (2) to adjust the pH to 4-6.
10. A multi-layer composite protective coating for the surface of a salt-based building decoration material, characterized in that, The invention comprises an inorganic densification layer and an organic-inorganic hybrid hydrophobic layer alternately constructed on the surface of a base matrix, wherein the inorganic densification layer is disposed in the innermost layer and the organic-inorganic hybrid hydrophobic layer is disposed in the outermost layer; the thickness of the inorganic densification layer is 1-10 μm and the thickness of the organic-inorganic hybrid hydrophobic layer is 1-10 μm.