Anti-fingerprint melamine decorative panel and preparation process thereof

Abstract

The invention relates to the field of melamine decorative panels, in particular to an anti-fingerprint melamine decorative panel and a preparation process thereof. Glucose is used to replace formaldehyde to synthesize melamine resin with melamine and urea, and then the melamine resin is compounded with composite cellulose nanocrystals and modified silicon dioxide to prepare melamine dipping solution; dodecyltriethoxysilane is used to modify the nano silicon dioxide; the fiber nanocrystals are firstly sulfonated and carboxylated in sequence, and then phytic acid is used as an intermediate to graft a flame retardant ionic liquid; poplar wood is used as a substrate raw material, is firstly treated with a sodium hydroxide solution, and gelatin, melamine dipping solution, wood and silicon dioxide are combined with reference to bionic mineralization.

Description

Technical Field

[0001] The invention relates to the field of melamine decorative panels, in particular to an anti-fingerprint melamine decorative panel and a preparation process thereof. Background Art

[0002] In the current home decoration market, melamine veneer panels are popular among consumers due to their high weather resistance and varied graphic styles. Melamine veneer panels are made by laminating wood boards and melamine impregnated paper at high temperatures, but traditional melamine veneer panels mostly use melamine and formaldehyde to prepare the impregnation solution, which is not conducive to environmental friendliness and human health.

[0003] In addition, traditional melamine decorative panels also have poor stain resistance and weak scratch resistance. For example, although the existing melamine skin-feel matte decorative panels feel good, they easily leave fingerprints or stains after touching, are difficult to clean, and minor scratches are not easy to eliminate, thus affecting the aesthetics. Summary of the invention

[0004] The object of the present invention is to provide an anti-fingerprint melamine decorative panel and a preparation process thereof, so as to solve the problems in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A preparation process of an anti-fingerprint melamine decorative panel comprises the following steps:

[0007] S1: preparing melamine dipping solution using composite fiber nanocrystals, modified silica and melamine resin;

[0008] S2: After cutting, the base paper is immersed in melamine dipping solution to make the impregnation amount of the paper 185-190g / m 2 , drying to obtain impregnated film paper;

[0009] S3: The log is sequentially subjected to sodium hydroxide impregnation treatment, gelatin-citric acid vacuum impregnation treatment, and pressure impregnation treatment with melamine impregnation liquid containing ethyl orthosilicate, and dried to obtain a substrate;

[0010] S4: spraying water mist on the impregnated adhesive film paper, and hot pressing with the substrate to obtain an anti-fingerprint melamine decorative panel.

[0011] Furthermore, after the water mist treatment, the moisture content of the impregnated film paper is 17-20%.

[0012] Furthermore, the working conditions of hot pressing are: pressure of 2 MPa, time of 5 min, and temperature of 160-170°C.

[0013] Furthermore, the composition of the melamine impregnation solution is, by weight, 1-3 parts of composite fiber nanocrystals, 3-7 parts of modified silicon dioxide, and 15-20 parts of melamine resin.

[0014] Furthermore, the preparation of the substrate includes the following steps:

[0015] (1) soaking the poplar wood in a sodium hydroxide aqueous solution for 5-6 hours to obtain pretreated poplar wood;

[0016] (2) mixing gelatin and deionized water, adding a mixture of citric acid and deionized water, placing the pretreated poplar wood in the mixture, and performing vacuum impregnation treatment to obtain the poplar wood to be treated;

[0017] (3) Mix melamine impregnation solution, tetraethyl orthosilicate and deionized water, adjust the pH value of the solution to 3, and perform pressure impregnation treatment on the poplar wood to obtain a substrate.

[0018] Furthermore, the working conditions of the vacuum impregnation treatment are: time is 2 hours, negative pressure is 0.1 MPa; the working conditions of the pressurized impregnation treatment are: pressure is 0.8 MPa, temperature is 30° C., and time is 8-10 hours.

[0019] Further, the preparation of composite fiber nanocrystals includes the following steps:

[0020] 1) Soaking cotton pulp in a NaOH solution, washing until the pH value is neutral, drying, mixing the alkali-treated cotton pulp with a sulfuric acid solution, stirring at 50°C for 1 hour, adding deionized water to terminate the reaction, centrifuging, washing, and dialyzing until the pH value is neutral to obtain sulfonated fiber nanocrystals; mixing the sulfonated fiber nanocrystals and deionized water, adding citric acid monohydrate, ultrasonically treating for 30 minutes, keeping warm at 120°C for 12 hours, centrifuging with ethanol, and dialyzing with deionized water for 5 days to obtain carboxylated fiber nanocrystals;

[0021] 2) tetrabutylphosphonium bromide, sodium fluoroborate and deionized water were mixed, stirred at 30° C. for 24 h, dichloromethane was added, the mixture was separated, rotary evaporated and dried to obtain a flame retardant ionic liquid;

[0022] 3) Mix the carboxylated fiber nanocrystals and deionized water, add phytic acid and copper acetate, keep warm at 170° C. for 5 min, add 20 mL of deionized water, and rinse with deionized water for 3-5 times to obtain pretreated fiber nanocrystals;

[0023] 4) In a nitrogen atmosphere, the pretreated fiber nanocrystals and deionized water were mixed, flame retardant ionic liquid, azobisisobutyronitrile and methanol were added, the mixture was kept at 25°C for 10 min, kept at 70°C for 24 h, extracted with methanol by Soxhlet for 2 d, and dried to obtain composite fiber nanocrystals.

[0024] Further, the preparation of melamine resin comprises the following steps:

[0025] Mix glucose and deionized water, heat to 60°C, add melamine, add copper sulfate to adjust the pH of the solution to 3, add urea, heat to 100°C and keep warm until the color of the solution changes to reddish brown, adjust the pH of the solution to 7-8, cool to 40°C, add boric acid and itaconic acid, stir for 1 hour, and obtain melamine resin.

[0026] Furthermore, the preparation of modified silica includes the following steps: mixing nano-silica and ethanol, stirring at 70°C for 3 minutes, adding sodium hydroxide and dodecyltriethoxysilane, keeping warm at 70°C for 5 hours, adjusting the pH value of the solution to 6-7, centrifuging, washing, and drying to obtain modified silica.

[0027] Beneficial effects of the present invention:

[0028] The invention provides an anti-fingerprint melamine decorative panel and a preparation process thereof. A processed substrate is hot-pressed and laminated with melamine impregnated paper to prepare a formaldehyde-free melamine decorative panel with good flame retardancy, strong compression resistance, super hydrophobicity, scratch resistance and anti-fingerprint properties.

[0029] Glucose is used instead of formaldehyde to synthesize melamine resin with melamine and urea, and then compounded with composite cellulose nanocrystals and modified silica to prepare melamine impregnation solution, which significantly improves the flame retardancy and tensile strength of the base paper without releasing formaldehyde.

[0030] Dodecyltriethoxysilane is selected to modify nano-silica, so that the melamine dipping solution has a super-hydrophobic and scratch-resistant surface after forming a film on the base paper; fiber nanocrystals are introduced to synergistically improve the super-hydrophobicity, but the fiber nanocrystals have the problem of easy agglomeration, etc. The present invention first sulfonates and carboxylates the fiber nanocrystals in sequence, and then uses phytic acid as an intermediate to graft a flame retardant ionic liquid. While improving the dispersion uniformity of the fiber nanocrystals in the melamine dipping solution, the introduction of phytic acid and the flame retardant ionic liquid gives the panel high flame retardancy and anti-fingerprint properties, and phytic acid and melamine can generate ammonium phytate, thereby further improving its flame retardancy.

[0031] Poplar wood is selected as the raw material of the substrate. It is first treated with sodium hydroxide solution to release the free hydroxyl groups in the poplar wood and improve the reactivity of the wood. Then, gelatin, which is widely available, low-priced, non-toxic and harmless, and green and environmentally friendly, is selected as an inducer. With reference to bionic mineralization, gelatin, melamine impregnation solution, wood, and silica are combined to form a film of gelatin and melamine resin on the cell wall or cell gap of the wood. The side chain active groups provide nucleation sites for silica and composite fiber nanocrystals, inducing silica and composite fiber nanocrystals to be deposited in an orderly manner on the wood cell wall and wood pores, thereby greatly improving the mildew resistance, flame retardancy and compression resistance of the substrate. DETAILED DESCRIPTION

[0032] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that if the embodiments of the present invention involve directional indications such as up, down, left, right, front, back, etc., the directional indication is only used to explain a specific posture such as the relative position relationship between the components, the movement status, etc. If the specific posture changes, the directional indication will also change accordingly. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0034] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention, and are not used to limit the present invention.

[0035] Embodiment 1: A process for preparing an anti-fingerprint melamine decorative panel, comprising the following steps:

[0036] S1: preparing melamine dipping solution using composite fiber nanocrystals, modified silica and melamine resin;

[0037] The composition of the melamine dipping solution is as follows: 1 part of composite fiber nanocrystals, 3 parts of modified silicon dioxide, and 15 parts of melamine resin, in parts by mass;

[0038] The preparation of composite fiber nanocrystals includes the following steps:

[0039] 1) Soak 2g of cotton pulp in a 4wt% NaOH solution, wash until the pH value is neutral, dry, mix 2g of alkali-treated cotton pulp with 40mL of 64wt% sulfuric acid solution, stir at 50°C for 1h, add deionized water to terminate the reaction, centrifuge, wash, and dialyze until the pH value is neutral to obtain sulfonated fiber nanocrystals; mix 2g of sulfonated fiber nanocrystals and 198mL of deionized water, add 50g of citric acid monohydrate, ultrasonically treat for 30min, keep warm at 120°C for 12h, centrifuge with ethanol, and dialyze with deionized water for 5d to obtain carboxylated fiber nanocrystals;

[0040] 2) 8.8 g of tetrabutylphosphonium bromide, 2.5 g of sodium fluoroborate, and 200 mL of deionized water were mixed, stirred at 30° C. for 24 h, 25 mL of dichloromethane was added, the mixture was separated, rotary evaporated, and dried to obtain a flame retardant ionic liquid;

[0041] 3) 0.4 g of carboxylated fiber nanocrystals and 20 mL of deionized water were mixed, 5 g of phytic acid and 5 mg of copper acetate were added, the mixture was heated at 170° C. for 5 min, 20 mL of deionized water was added, and the mixture was rinsed with deionized water for 3 times to obtain pretreated fiber nanocrystals;

[0042] 4) Under a nitrogen atmosphere, 0.4 g of pretreated fiber nanocrystals and 10 mL of deionized water were mixed, 2 g of flame retardant ionic liquid, 30 mg of azobisisobutyronitrile, and 2 mL of methanol were added, and the mixture was kept at 25° C. for 10 min, kept at 70° C. for 24 h, extracted with methanol for 2 d, and dried to obtain composite fiber nanocrystals;

[0043] The preparation of melamine resin comprises the following steps:

[0044] 2mmol glucose and 50mL deionized water were mixed, the temperature was raised to 60°C, 0.5mmol melamine was added, copper sulfate was added to adjust the solution pH to 3, 2mmol urea was added, the temperature was raised to 100°C and kept until the solution color changed to reddish brown, the solution pH was adjusted to 7, the temperature was lowered to 40°C, 0.1g boric acid and 0.12g itaconic acid were added, and the mixture was stirred for 1h to obtain melamine resin;

[0045] The preparation of modified silica includes the following steps: mixing 2 g of nano-silica and 100 mL of ethanol, stirring at 70° C. for 3 min, adding 500 mg of sodium hydroxide and 0.6 mL of dodecyltriethoxysilane, keeping at 70° C. for 5 h, adjusting the pH value of the solution to 6, centrifuging, washing, and drying to obtain modified silica;

[0046] S2: After cutting, the base paper is immersed in melamine dipping solution to make the impregnation amount of the paper 185g / m 2 , drying to obtain impregnated film paper;

[0047] S3: The log is sequentially subjected to sodium hydroxide impregnation treatment, gelatin-citric acid vacuum impregnation treatment, and pressure impregnation treatment with melamine impregnation liquid containing ethyl orthosilicate, and dried to obtain a substrate;

[0048] The preparation of the substrate includes the following steps:

[0049] (1) soaking the poplar wood in a 2% sodium hydroxide aqueous solution for 5 hours to obtain pretreated poplar wood;

[0050] (2) 0.1 g of gelatin and 100 mL of deionized water were mixed, 0.5 g of citric acid and 100 mL of deionized water were added, 4 g of pretreated poplar wood was placed in the mixture, and vacuum impregnation treatment was performed to obtain the poplar wood to be treated;

[0051] (3) 10 g of melamine impregnation solution, 4 g of tetraethyl orthosilicate, and 1 g of deionized water were mixed, the pH of the solution was adjusted to 3, and 4 g of the to-be-treated poplar wood was subjected to pressure impregnation treatment to obtain a substrate;

[0052] The working conditions of vacuum impregnation treatment are: time is 2 hours, negative pressure is 0.1MPa; the working conditions of pressurized impregnation treatment are pressure 0.8MPa, temperature 30℃, time 8 hours;

[0053] S4: spraying water mist on the impregnated film paper to make its moisture content 17%, and hot pressing with the substrate to obtain an anti-fingerprint melamine veneer panel;

[0054] The working conditions of hot pressing are: pressure of 2 MPa, time of 5 min, and temperature of 160 °C.

[0055] Embodiment 2: A process for preparing an anti-fingerprint melamine decorative panel, comprising the following steps:

[0056] S1: preparing melamine dipping solution using composite fiber nanocrystals, modified silica and melamine resin;

[0057] The composition of the melamine dipping solution is as follows: 2 parts of composite fiber nanocrystals, 5 parts of modified silicon dioxide, and 17 parts of melamine resin, in terms of mass parts;

[0058] The preparation of composite fiber nanocrystals includes the following steps:

[0059] 1) Soak 2g of cotton pulp in a 4wt% NaOH solution, wash until the pH value is neutral, dry, mix 2g of alkali-treated cotton pulp with 40mL of 64wt% sulfuric acid solution, stir at 50°C for 1h, add deionized water to terminate the reaction, centrifuge, wash, and dialyze until the pH value is neutral to obtain sulfonated fiber nanocrystals; mix 2g of sulfonated fiber nanocrystals and 198mL of deionized water, add 50g of citric acid monohydrate, ultrasonically treat for 30min, keep warm at 120°C for 12h, centrifuge with ethanol, and dialyze with deionized water for 5d to obtain carboxylated fiber nanocrystals;

[0060] 2) 8.8 g of tetrabutylphosphonium bromide, 2.5 g of sodium fluoroborate, and 200 mL of deionized water were mixed, stirred at 30° C. for 24 h, 25 mL of dichloromethane was added, the liquids were separated, rotary evaporated, and dried to obtain a flame retardant ionic liquid;

[0061] 3) 0.4 g of carboxylated fiber nanocrystals and 20 mL of deionized water were mixed, 5 g of phytic acid and 5 mg of copper acetate were added, the mixture was heated at 170° C. for 5 min, 20 mL of deionized water was added, and the mixture was rinsed with deionized water for 4 times to obtain pretreated fiber nanocrystals;

[0062] 4) Under a nitrogen atmosphere, 0.4 g of pretreated fiber nanocrystals and 10 mL of deionized water were mixed, 2 g of flame retardant ionic liquid, 30 mg of azobisisobutyronitrile, and 2 mL of methanol were added, and the mixture was kept at 25° C. for 10 min, kept at 70° C. for 24 h, extracted with methanol for 2 d, and dried to obtain composite fiber nanocrystals;

[0063] The preparation of melamine resin comprises the following steps:

[0064] 2mmol glucose and 50mL deionized water were mixed, the temperature was raised to 60°C, 0.5mmol melamine was added, copper sulfate was added to adjust the pH of the solution to 3, 2mmol urea was added, the temperature was raised to 100°C and kept until the solution color changed to reddish brown, the pH of the solution was adjusted to 7.5, the temperature was lowered to 40°C, 0.1g boric acid and 0.12g itaconic acid were added, and the mixture was stirred for 1h to obtain melamine resin;

[0065] The preparation of modified silica includes the following steps: mixing 2 g of nano-silica and 100 mL of ethanol, stirring at 70° C. for 3 min, adding 500 mg of sodium hydroxide and 0.6 mL of dodecyltriethoxysilane, keeping at 70° C. for 5 h, adjusting the pH value of the solution to 6.5, centrifuging, washing, and drying to obtain modified silica;

[0066] S2: After cutting, the base paper is immersed in melamine dipping solution to make the impregnation amount of the paper 188g / m 2 , drying to obtain impregnated film paper;

[0067] S3: The log is sequentially subjected to sodium hydroxide impregnation treatment, gelatin-citric acid vacuum impregnation treatment, and pressure impregnation treatment with melamine impregnation liquid containing ethyl orthosilicate, and dried to obtain a substrate;

[0068] The preparation of the substrate includes the following steps:

[0069] (1) soaking the poplar wood in a 2% sodium hydroxide aqueous solution for 5.5 hours to obtain pretreated poplar wood;

[0070] (2) 0.1 g of gelatin and 100 mL of deionized water were mixed, 0.5 g of citric acid and 100 mL of deionized water were added, 2 g of pretreated poplar wood was placed in the mixture, and vacuum impregnation treatment was performed to obtain the poplar wood to be treated;

[0071] (3) 10 g of melamine impregnation solution, 4 g of tetraethyl orthosilicate, and 1 g of deionized water were mixed, the pH of the solution was adjusted to 3, and 4 g of the to-be-treated poplar wood was subjected to pressure impregnation treatment to obtain a substrate;

[0072] The working conditions of vacuum impregnation treatment are: time is 2 hours, negative pressure is 0.1MPa; the working conditions of pressurized impregnation treatment are pressure 0.8MPa, temperature 30℃, time 9 hours;

[0073] S4: spraying water mist on the impregnated film paper to make its moisture content 18%, and hot pressing with the substrate to obtain an anti-fingerprint melamine veneer panel;

[0074] The working conditions of hot pressing are: pressure of 2 MPa, time of 5 min, and temperature of 165 °C.

[0075] Embodiment 3: A process for preparing an anti-fingerprint melamine decorative panel, comprising the following steps:

[0076] S1: preparing melamine dipping solution using composite fiber nanocrystals, modified silica and melamine resin;

[0077] The composition of the melamine dipping solution is as follows: 3 parts of composite fiber nanocrystals, 7 parts of modified silicon dioxide, and 20 parts of melamine resin, in terms of mass parts;

[0078] The preparation of composite fiber nanocrystals includes the following steps:

[0079] 1) Soak 2g of cotton pulp in a 4wt% NaOH solution, wash until the pH value is neutral, dry, mix 2g of alkali-treated cotton pulp with 40mL of 64wt% sulfuric acid solution, stir at 50°C for 1h, add deionized water to terminate the reaction, centrifuge, wash, and dialyze until the pH value is neutral to obtain sulfonated fiber nanocrystals; mix 2g of sulfonated fiber nanocrystals and 198mL of deionized water, add 50g of citric acid monohydrate, ultrasonically treat for 30min, keep warm at 120°C for 12h, centrifuge with ethanol, and dialyze with deionized water for 5d to obtain carboxylated fiber nanocrystals;

[0080] 2) 8.8 g of tetrabutylphosphonium bromide, 2.5 g of sodium fluoroborate, and 200 mL of deionized water were mixed, stirred at 30° C. for 24 h, 25 mL of dichloromethane was added, the liquids were separated, rotary evaporated, and dried to obtain a flame retardant ionic liquid;

[0081] 3) 0.4 g of carboxylated fiber nanocrystals and 20 mL of deionized water were mixed, 5 g of phytic acid and 5 mg of copper acetate were added, the mixture was heated at 170° C. for 5 min, 20 mL of deionized water was added, and the mixture was rinsed with deionized water for 5 times to obtain pretreated fiber nanocrystals;

[0082] 4) Under a nitrogen atmosphere, 0.4 g of pretreated fiber nanocrystals and 10 mL of deionized water were mixed, 2 g of flame retardant ionic liquid, 30 mg of azobisisobutyronitrile, and 2 mL of methanol were added, and the mixture was kept at 25° C. for 10 min, kept at 70° C. for 24 h, extracted with methanol for 2 d, and dried to obtain composite fiber nanocrystals;

[0083] The preparation of melamine resin comprises the following steps:

[0084] 2mmol glucose and 50mL deionized water were mixed, the temperature was raised to 60°C, 0.5mmol melamine was added, copper sulfate was added to adjust the pH value of the solution to 3, 2mmol urea was added, the temperature was raised to 100°C and kept until the solution color changed to reddish brown, the pH value of the solution was adjusted to 8, the temperature was lowered to 40°C, 0.1g boric acid and 0.12g itaconic acid were added, and the mixture was stirred for 1h to obtain melamine resin;

[0085] The preparation of modified silica includes the following steps: mixing 2 g of nano-silica and 100 mL of ethanol, stirring at 70° C. for 3 min, adding 500 mg of sodium hydroxide and 0.6 mL of dodecyltriethoxysilane, keeping at 70° C. for 5 h, adjusting the pH value of the solution to 6-7, centrifuging, washing, and drying to obtain modified silica;

[0086] S2: After cutting, the base paper is immersed in melamine dipping solution to make the impregnation amount of the paper 190g / m 2 , drying to obtain impregnated film paper;

[0087] S3: The log is sequentially subjected to sodium hydroxide impregnation treatment, gelatin-citric acid vacuum impregnation treatment, and pressure impregnation treatment with melamine impregnation liquid containing ethyl orthosilicate, and dried to obtain a substrate;

[0088] The preparation of the substrate includes the following steps:

[0089] (1) soaking the poplar wood in a 2% sodium hydroxide aqueous solution for 6 hours to obtain pretreated poplar wood;

[0090] (2) 0.1 g of gelatin and 100 mL of deionized water were mixed, 0.5 g of citric acid and 100 mL of deionized water were added, 2 g of pretreated poplar wood was placed in the mixture, and vacuum impregnation treatment was performed to obtain the poplar wood to be treated;

[0091] (3) 10 g of melamine impregnation solution, 4 g of tetraethyl orthosilicate, and 1 g of deionized water were mixed, the pH of the solution was adjusted to 3, and 4 g of the to-be-treated poplar wood was subjected to pressure impregnation treatment to obtain a substrate;

[0092] The working conditions of vacuum impregnation treatment are: time is 2 hours, negative pressure is 0.1MPa; the working conditions of pressurized impregnation treatment are pressure 0.8MPa, temperature 30℃, time 10 hours;

[0093] S4: spraying water mist on the impregnated film paper to make its moisture content 20%, and hot pressing with the substrate to obtain an anti-fingerprint melamine veneer panel;

[0094] The working conditions of hot pressing are: pressure of 2 MPa, time of 5 min, and temperature of 170 °C.

[0095] Comparative Example 1: Taking Example 3 as the control group, the carboxylated fiber nanocrystals replaced the composite fiber nanocrystals, and the other processes were normal.

[0096] Comparative Example 2: Taking Example 3 as the control group, nano-silicon dioxide replaced the modified silicon dioxide, and the other processes were normal.

[0097] Comparative Example 3: Taking Example 3 as the control group, the melamine dipping solution was replaced by melamine resin, and the other processes were normal.

[0098] Comparative Example 4: Example 3 was used as the control group, in which no melamine impregnation solution was added during the preparation of the substrate, and other processes were normal.

[0099] Comparative Example 5: Example 3 was used as the control group, gelatin was not added in the preparation of the substrate, and other processes were normal.

[0100] Comparative Example 6: Example 3 was used as the control group, in which no ethyl orthosilicate was added during the preparation of the substrate, and other processes were normal.

[0101] Comparative Example 7: Taking Example 3 as the control group, the base plate was replaced with poplar wood, and the other processes were normal.

[0102] Source of raw materials:

[0103] Cotton pulp (short cotton linter): Shandong Yinying Chemical Fiber Co., Ltd.; Glucose 123: Wuhan Chujiang Haoyu Chemical Technology Development Co., Ltd.; Poplar (fast-growing plantation poplar, thickness 19mm): collected from Changzhou City, Jiangsu Province; Base paper (85g / m 2 ): Changzhou Oubai Decoration Materials Co., Ltd.; Tetrabutyl phosphonium bromide T107471, sodium fluoroborate S104899, phytic acid P350767, azobisisobutyronitrile A104255, melamine M108433, boric acid B111592, itaconic acid I106140, nano-silica S104597, dodecyltriethoxysilane D155295, gelatin G108394, ethyl orthosilicate T110596: Aladdin reagent; NaOH, citric acid monohydrate, ethanol, dichloromethane, copper acetate, methanol, copper sulfate, urea, analytical grade: Sinopharm Group reagent.

[0104] Performance Test:

[0105] Hydrophobicity: tested with a 2μL water droplet;

[0106] Impact performance: refer to ASTMD143-14 test, pendulum energy 100J, prepared into 30mm×20mm×20mm, span to thickness ratio 12:1, repeat the test 8 times and take the average value;

[0107] Immersion peeling strength: refer to the immersion peeling experiment in GB / T17657 for testing, cut into 75mm×75mm×20mm, immerse and keep warm at 65℃ for 3h, dry, observe and measure the peeling length L of the four sides, and the immersion peeling strength grade classification standard; L=0, no peeling; L=0-25mm, slight peeling; L greater than 25mm, severe peeling, unqualified;

[0108] Refer to UL-94 for testing the combustion level; refer to GB18580-2017 for determining the formaldehyde emission; the specific data are shown in Table 1;

[0109] Table 1

[0110]

[0111]

[0112] Examples 1-3 are melamine decorative panels prepared according to the present invention. The formaldehyde emission limit of the melamine decorative panels prepared according to the present invention is less than 0.009 mg / m 3 , which meets health requirements; the present invention provides an anti-fingerprint melamine decorative panel and a preparation process thereof, wherein the treated substrate is hot-pressed and laminated with melamine impregnated paper to prepare a formaldehyde-free, flame-retardant, compressive-resistant, super-hydrophobic, scratch-resistant and anti-fingerprint melamine decorative panel.

[0113] By comparing Example 3 with Comparative Example 1, it can be seen that the fiber nanocrystals are introduced to synergistically improve the superhydrophobicity, but the fiber nanocrystals have the problem of easy agglomeration. The present invention first sulfonates and carboxylates the fiber nanocrystals in sequence, and then uses phytic acid as an intermediate to graft the flame retardant ionic liquid. While improving the dispersion uniformity of the fiber nanocrystals in the melamine dipping solution, the introduction of phytic acid and flame retardant ionic liquid gives the panel high flame retardancy, super hydrophobicity and anti-fingerprint properties.

[0114] By comparing Example 3 with Comparative Example 2, it can be seen that dodecyltriethoxysilane is used to modify the nano-silicon dioxide, so that the melamine dipping solution has a super-hydrophobic and scratch-resistant surface after forming a film on the base paper.

[0115] By comparing Example 3 with Comparative Example 3, it can be seen that by using glucose instead of formaldehyde to synthesize melamine resin with melamine and urea, and then compounding it with composite cellulose nanocrystals and modified silica to prepare melamine impregnation solution, the flame retardancy and tensile strength of base paper are significantly improved without releasing formaldehyde.

[0116] By comparing Example 3 with Comparative Examples 4, 5, 6 and 7, it can be seen that poplar wood is selected as the raw material for the substrate, and is first treated with a sodium hydroxide solution to release the free hydroxyl groups in the poplar wood and improve the reactivity of the wood. Then, gelatin, which is widely available, inexpensive, non-toxic, harmless and green, is selected as an inducer. With reference to bionic mineralization, gelatin, melamine impregnation solution, wood and silica are combined to form a film of gelatin and melamine resin on the cell wall or cell gap of the wood. The side chain active groups provide nucleation sites for silica and composite fiber nanocrystals, inducing the orderly deposition of silica and composite fiber nanocrystals on the cell wall and pores of the wood, thereby greatly improving the mildew resistance, flame retardancy and compression resistance of the substrate.

[0117] The above description is only an embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural changes made by using the present invention specification under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A preparation process of anti-fingerprint melamine decorative panel, It is characterized in that The following steps are involved: S1: preparing melamine dipping solution using composite fiber nanocrystals, modified silica and melamine resin; S2: After cutting, the base paper is immersed in melamine dipping solution to make the impregnation amount of the paper 185-190g / m 2 , drying to obtain impregnated film paper; S3: The log is sequentially subjected to sodium hydroxide impregnation treatment, gelatin-citric acid vacuum impregnation treatment, and pressure impregnation treatment with melamine impregnation liquid containing ethyl orthosilicate, and dried to obtain a substrate; S4: spraying water mist on the impregnated adhesive film paper, and hot pressing with the substrate to obtain an anti-fingerprint melamine veneer panel; The preparation of composite fiber nanocrystals includes the following steps: 1) Soaking cotton pulp in a NaOH solution, washing until the pH value is neutral, drying, mixing the alkali-treated cotton pulp with a sulfuric acid solution, stirring at 50°C for 1 hour, adding deionized water to terminate the reaction, centrifuging, washing, and dialyzing until the pH value is neutral to obtain sulfonated fiber nanocrystals; mixing the sulfonated fiber nanocrystals and deionized water, adding citric acid monohydrate, ultrasonically treating for 30 minutes, keeping warm at 120°C for 12 hours, centrifuging with ethanol, and dialyzing with deionized water for 5 days to obtain carboxylated fiber nanocrystals; 2) tetrabutylphosphonium bromide, sodium fluoroborate and deionized water were mixed, stirred at 30° C. for 24 h, dichloromethane was added, the mixture was separated, rotary evaporated and dried to obtain a flame retardant ionic liquid; 3) Mix the carboxylated fiber nanocrystals and deionized water, add phytic acid and copper acetate, keep warm at 170° C. for 5 min, add 20 mL of deionized water, and rinse with deionized water for 3-5 times to obtain pretreated fiber nanocrystals; 4) In a nitrogen atmosphere, the pretreated fiber nanocrystals and deionized water were mixed, flame retardant ionic liquid, azobisisobutyronitrile and methanol were added, the mixture was kept at 25° C. for 10 min, kept at 70° C. for 24 h, extracted with methanol for 2 d, and dried to obtain composite fiber nanocrystals; The preparation of melamine resin comprises the following steps: Mix glucose and deionized water, heat to 60°C, add melamine, add copper sulfate to adjust the pH of the solution to 3, add urea, heat to 100°C and keep warm until the solution color changes to reddish brown, adjust the pH of the solution to 7-8, cool to 40°C, add boric acid and itaconic acid, stir for 1 hour, and obtain melamine resin; The preparation of modified silica includes the following steps: mixing nano-silica and ethanol, stirring at 70°C for 3 minutes, adding sodium hydroxide and dodecyltriethoxysilane, keeping at 70°C for 5 hours, adjusting the pH value of the solution to 6-7, centrifuging, washing, and drying to obtain modified silica.

2. A process for preparing an anti-fingerprint melamine decorative panel according to claim 1, It is characterized in that After the water mist treatment, the moisture content of the impregnated film paper is 17-20%.

3. The preparation process of the anti-fingerprint melamine decorative panel according to claim 1, It is characterized in that The working conditions of hot pressing are: pressure of 2MPa, time of 5min, temperature of 160-170℃.

4. The preparation process of the anti-fingerprint melamine decorative panel according to claim 1, It is characterized in that Calculated by weight, the composition of the melamine dipping solution is: 1-3 parts of composite fiber nanocrystals, 3-7 parts of modified silicon dioxide, and 15-20 parts of melamine resin.

5. The preparation process of the anti-fingerprint melamine decorative panel according to claim 1, It is characterized in that The preparation of the substrate includes the following steps: (1) soaking the poplar wood in a sodium hydroxide aqueous solution for 5-6 hours to obtain pretreated poplar wood; (2) mixing gelatin and deionized water, adding a mixture of citric acid and deionized water, placing the pretreated poplar wood in the mixture, and performing vacuum impregnation treatment to obtain the poplar wood to be treated; (3) Mix melamine impregnation solution, tetraethyl orthosilicate and deionized water, adjust the pH value of the solution to 3, and perform pressure impregnation treatment on the poplar wood to obtain a substrate.

6. A process for preparing an anti-fingerprint melamine decorative panel according to claim 5, It is characterized in that The working conditions of the vacuum impregnation treatment are: time is 2 hours, negative pressure is 0.1MPa; the working conditions of the pressurized impregnation treatment are: pressure is 0.8MPa, temperature is 30°C, and time is 8-10 hours. 7.An anti-fingerprint melamine veneer panel, It is characterized in that The invention is prepared by the preparation process according to any one of claims 1 to 6.

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