An anti-UV masking tape and its manufacturing method

Abstract

The present invention relates to the technical field of masking tape, and solves the technical deficiencies that the functional layer structure and its component ratio of existing products are unreasonable, the tape has poor UV resistance, and there is residual glue after long-term adhesion and removal. The technical solution includes a release layer, a masking paper substrate layer and an adhesive layer. An ultraviolet absorption coating is applied on the masking paper substrate layer to form an ultraviolet absorption layer, and an ultraviolet reflection coating is applied on the ultraviolet absorption layer to form an ultraviolet reflection layer; the ultraviolet absorption coating contains benzophenone and / or octyl dimethylaminobenzoate and / or resorcinol monobenzoate; the ultraviolet reflection coating contains nano-titanium dioxide and / or zinc oxide. The beneficial effects of the present invention are as follows: The hierarchical design and component ratio of the anti-UV functional layer structure are optimized. After most of the ultraviolet rays are reflected by the ultraviolet reflection layer, the remaining ultraviolet rays are completely absorbed by the ultraviolet absorption layer, blocking the damage of ultraviolet rays to the adhesive layer, reducing the coating dosage, having a better anti-UV effect, and there will be no residual glue after the tape is removed.

Description

Technical Field

[0001] The present invention relates to the technical field of masking tape, and more specifically to a high-efficiency anti-UV masking tape that shields ultraviolet rays by means of step-by-step and layer-by-layer filtering of UV rays and does not leave residual glue, as well as a method for manufacturing such a masking tape. Background Art

[0002] Masking tape is generally used for masking and protecting in operations such as decoration (spraying). For example, during the construction of the exterior wall of a building, the part to be blocked needs to be covered with masking tape, and after the coating dries, the masking tape is removed. In the outdoor construction state, masking tape will inevitably be irradiated by ultraviolet rays under sunlight. During this process, ultraviolet rays will penetrate the masking tape substrate and damage the molecular chain structure of the adhesive, making the intermolecular cohesion of the adhesive poor, resulting in glue remaining on the adhered object when the tape is removed, which is difficult to clean and brings unnecessary trouble to subsequent processing work.

[0003] In order to solve the problem of residual glue on the masking tape after being irradiated by ultraviolet rays, some masking tapes with anti-ultraviolet functions have emerged on the market. For example, in a patent for invention with the Chinese patent authorization publication number "CN208762790U", an anti-ultraviolet masking paper and masking tape are disclosed. An anti-ultraviolet coating is added between the styrene-butadiene latex surface layer and the styrene-butadiene latex bottom layer or hydroxylated styrene-butadiene latex bottom layer. This anti-ultraviolet coating is a structural layer formed by acrylate type, nano-titanium dioxide or benzophenone coating. The principle of anti-ultraviolet is to utilize the characteristics of the styrene-butadiene latex bottom layer or hydroxylated styrene-butadiene latex bottom layer to enhance the bonding strength between the masking paper and the pigment and the wet friction resistance, and at the same time combine with anti-ultraviolet reagents to achieve the anti-UV effect.

[0004] However, the anti-ultraviolet coating of the masking tape disclosed in the above patent is a functional structural layer of a composite material. The anti-ultraviolet principles of acrylate, nano-titanium dioxide and benzophenone in the structural layer are different. For example, acrylate and titanium dioxide mainly reflect ultraviolet rays, while benzophenone mainly absorbs ultraviolet rays. The anti-UV effect of the single-layer anti-ultraviolet coating formed by mixing them into a coating is not the coupling and superposition of the two anti-ultraviolet forms. On the contrary, after the two functional raw materials are mixed into the same functional structural layer, the upper part of the structural layer cannot fully reflect the incident ultraviolet rays (due to the interference of the absorption component), and the lower part of the structural layer cannot fully absorb the remaining ultraviolet rays transmitted in (due to the interference of the reflection component), thereby reducing the anti-UV effect of the anti-ultraviolet coating and not achieving the purpose of completely filtering ultraviolet rays by 100%. Therefore, a small amount of ultraviolet rays will still penetrate to the glue surface. After long-term use, ultraviolet rays will still damage the molecular chain structure of the glue at the bottom layer of the masking tape, resulting in the problem of residual glue when the tape is removed.

[0005] In addition, a pressure-sensitive adhesive layer is coated on the other side of the masking paper base paper of the above-mentioned masking tape, and the masking paper base paper itself has poor anti-penetration, water resistance and oil resistance. After long-term use, the glue component of the pressure-sensitive adhesive layer will penetrate into the bottom layer of styrene-butadiene latex and the upper structural layer of the anti-ultraviolet coating, further affecting the anti-UV effect of the masking tape and aggravating the residual glue problem. Summary of the invention

[0006] To sum up, the purpose of the present invention is to solve the technical problems that the functional structural layer design of the existing masking tape is unreasonable, ultraviolet rays cannot be completely filtered out, there is still residual glue after the tape is removed, and the anti-UV effect is not ideal, and to provide an improved masking tape with high efficiency and no residual glue, in which the anti-UV layer is divided into an upper ultraviolet reflection layer and a lower ultraviolet absorption layer, which has the function of reflecting and absorbing ultraviolet rays layer by layer and has the function of reflecting and absorbing ultraviolet rays layer by layer.

[0007] In order to solve the technical deficiencies proposed by the present invention, the technical scheme adopted is: an anti-UV masking tape, comprising a release layer, a masking paper base layer and an adhesive layer from top to bottom, characterized in that it also comprises an ultraviolet absorption layer formed by coating an ultraviolet absorption coating on the upper surface of the masking paper base layer and curing, and an ultraviolet reflection layer formed by coating an ultraviolet reflection coating on the upper surface of the ultraviolet absorption layer and curing, wherein the release layer is arranged on the ultraviolet reflection layer, and any two adjacent layers are self-adhesively fixed; wherein the ultraviolet absorption coating comprises the following components in parts by weight: 20 to 26 parts of benzophenone and / or 6 to 10 parts of octyl paradimethylaminoformate and / or 3 to 5 parts of monobenzoic acid resorcinol ester; and the ultraviolet reflection coating comprises the following components in parts by weight: 8 to 16 parts of nano titanium dioxide and / or 3 to 9 parts of zinc oxide.

[0008] Furthermore, an isolation and anti-seepage layer is provided between the adhesive layer and the masking paper substrate layer. The isolation and anti-seepage layer is formed by impregnating a water-soluble styrene-acrylic emulsion on the bottom surface of the masking paper substrate layer and curing. The masking paper substrate layer absorbs 50-60 g / ㎡ of the water-soluble styrene-acrylic emulsion.

[0009] Furthermore, the adhesive layer is formed by coating rubber-type glue on the lower bottom surface of the isolation and anti-seepage layer and then curing it. The rubber-type glue contains the following components in parts by weight: 28 to 33 parts of mixed rubber, 4 to 6 parts of petroleum resin, 0.7 to 1.3 parts of cyclohexane oil, 1.0 to 1.5 parts of antioxidant, and 0.4 to 0.7 parts of curing agent.

[0010] Furthermore, the coating amount of the rubber type glue is 30 to 40 g / ㎡.

[0011] Furthermore, the coating amount of the ultraviolet reflective coating is 14 to 20 g / ㎡, and the coating amount of the ultraviolet absorbing coating is 10 to 16 g / ㎡.

[0012] Further, the release layer is formed by coating an aqueous silicone release agent on the upper surface of the ultraviolet reflection layer and curing it, and the coating amount of the aqueous silicone release agent is 2.8 - 3.8 g / ㎡.

[0013] Further, the pH value of the ultraviolet reflection coating is 8.0 - 9.5, and it contains the following components by weight: 10 - 12 parts of nano-titanium dioxide, 12 - 14 parts of dispersant, 3 - 6 parts of modifier, and 4 - 6 parts of zinc oxide.

[0014] Further, the dispersant is selected from one or more of phosphates, sulfonates, and sulfate esters; the modifier is selected from one or more of magnesium oxide, silicon oxide, aluminum oxide, barium sulfate, and aluminate.

[0015] The present invention also simultaneously discloses a method for manufacturing the above anti-UV masking paper tape, and the method includes the following steps:

[0016] Step 1 Substrate anti-permeation treatment: Take the required pre-prepared water-soluble styrene-acrylic emulsion, and impregnate it on the bottom surface of the masking paper substrate by an impregnation method, and form an isolation and anti-seepage layer after drying and curing.

[0017] Step 2 Coating ultraviolet absorption coating: Take the required pre-prepared ultraviolet absorption coating containing benzophenone and / or octyl dimethyl PABA and / or resorcinol monobenzoate, and coat it on the upper surface of the anti-permeation treated masking paper substrate by a scraping method, and form an ultraviolet absorption layer after drying and curing.

[0018] Step 3 Coating ultraviolet reflection coating: Take the required pre-prepared ultraviolet reflection coating containing nano-titanium dioxide and / or zinc oxide, and coat it on the upper surface of the ultraviolet absorption layer formed by curing by a scraping method, and form an ultraviolet reflection layer after drying and curing.

[0019] Step 4 Coating release agent: Take the required pre-prepared release agent, and coat it on the upper surface of the ultraviolet reflection layer formed by curing by a scraping method, and form a release layer after drying and curing.

[0020] Step 5 Gluing: Take the required pre-prepared rubber-based glue containing kneaded rubber, petroleum resin, naphthenic oil, antioxidant, and curing agent, and coat it on the bottom surface of the formed isolation and anti-seepage layer by a scraping method, and form an adhesive layer after drying and curing.

[0021] Further, the drying processes in steps 1 to 5 are respectively gradient-dried by a segmented dryer.

[0022] Compared with the prior art, the present invention has the following beneficial effects.

[0023] 1. The anti-UV functional layer of the masking tape of the present invention is divided into an upper UV reflection layer and a lower UV absorption layer. During the UV irradiation process, the upper UV reflection layer contains components of nano-titanium dioxide and / or zinc oxide that can reflect UV rays. Therefore, it can evenly reflect up to 80% of the UV rays, thus blocking the vast majority of UV rays. At the same time, the lower UV absorption layer contains components of benzophenone and / or octyl dimethyl aminobenzoate and / or resorcinol monobenzoate that can absorb UV rays. Therefore, it can evenly, fully, and thoroughly absorb the remaining UV rays that penetrate the reflection layer and convert them into heat for consumption, thereby achieving the purpose of gradually and layer-by-layer filtering out UV rays in the present invention, playing an excellent UV shielding role, blocking the penetration of UV rays through the masking paper substrate layer and damaging the molecular chain structure of the adhesive layer, and effectively solving the problem of residual glue after the masking tape is removed after long-term use.

[0024] 2. The present invention optimizes the composition ratio of the anti-UV components in the UV reflection layer and the UV absorption layer of the masking tape, enabling the UV reflection layer to reflect the vast majority of the incident UV rays to the greatest extent, reducing the difficulty for the UV absorption layer to thoroughly filter out the penetrated UV rays, ensuring the high anti-UV performance of the masking tape of the present invention, and avoiding the occurrence of the residual glue problem. At the same time, the optimization of the above composition ratio can also minimize the coating amounts of the UV reflection coating and the UV absorption coating, reduce the production cost of the masking tape, and improve the market competitiveness of the products of the present invention.

[0025] 3. An isolation and anti-seepage layer is provided on the bottom surface of the masking paper substrate layer of the present invention. This isolation and anti-seepage layer is a functional structural layer formed by curing water-soluble styrene-acrylic emulsion on the bottom surface of the masking paper substrate layer, and has excellent properties of water resistance, oil resistance, heat resistance, and aging resistance, enabling the masking paper of the present invention to have excellent anti-permeability and play a good two-way blocking role. During long-term use, the glue in the adhesive layer will not penetrate upward to the upper surface of the masking paper substrate layer, and at the same time, it can also block the downward penetration of the UV absorption coating, UV reflection coating, and release agent on the upper surface of the masking paper substrate layer into the adhesive layer and damage the molecular chain structure of the glue.

[0026] 4. The present invention optimizes the composition ratio of the adhesive layer. By adding honey-refined rubber, petroleum resin, and naphthenic oil, the glue has better viscosity. At the same time, the added antioxidant improves the aging resistance of the glue, enabling it to withstand high temperatures of about 80°C and low temperatures of about -20°C. In addition, the curing agent added to the glue can significantly improve the cohesion of the glue, further improving the UV resistance of the glue, and cooperating with the above isolation and anti-seepage layer, UV absorption layer, and UV reflection layer to play a synergistic effect, solving the problem of residual glue after the masking tape is removed after long-term outdoor irradiation. Description of the Drawings

[0027] Figure 1 This is a schematic diagram of the partial cross-sectional structure of the masking tape of the present invention.

[0028] In the figure: 1. Release layer, 2. UV reflection layer, 3. UV absorption layer, 4. Masking paper base layer, 5. Isolation and anti-seepage layer, 6. Adhesive layer. Specific embodiments

[0029] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described below through specific examples and comparative examples. Moreover, the specific implementation manners adopted in the following examples are only some preferred implementation manners of the technical solution of the present invention, and do not limit the present invention.

[0030] Refer to Figure 1 As shown, the overall thickness of the masking tape of the present invention is between 135 and 155 μm, and from top to bottom includes a release layer 1, a UV reflection layer 2, a UV absorption layer 3, a masking paper base layer 4, an isolation and anti-seepage layer 5, and an adhesive layer 6. The isolation and anti-seepage layer 5 is formed by impregnating the lower bottom surface of the masking paper base layer 4 with a water-soluble styrene-acrylic emulsion and then curing. The adhesive layer 6 is formed by coating the lower bottom surface of the isolation and anti-seepage layer 5 with a rubber-based glue and then curing. The UV absorption layer 3 is formed by coating the upper surface of the masking paper base layer 4 with a UV absorption coating and then curing. The UV reflection layer 2 is formed by coating the upper surface of the UV absorption layer 3 with a UV reflection coating and then curing. The release layer 1 is formed by coating the upper surface of the UV reflection layer 2 with a water-based silicone release agent and then curing.

[0031] By weight, the UV reflection coating contains 8-16 parts of nano-titanium dioxide and / or 3-9 parts of zinc oxide, the UV absorption coating contains 20-26 parts of benzophenone and / or 6-10 parts of octyl dimethylaminobenzoate and / or 3-5 parts of resorcinol monobenzoate, and the rubber-based glue contains 28-33 parts of milled rubber, 4-6 parts of petroleum resin, 0.7-1.3 parts of naphthenic oil, 1.0-1.5 parts of antioxidant, and 0.4-0.7 parts of curing agent.

[0032] Specifically, the absorption amount of the water-soluble styrene-acrylic emulsion absorbed by the lower bottom surface of the masking paper base layer 4 is 50-60 g / ㎡ (wet weight), the coating amount of the UV absorption coating on the upper surface of the masking paper is 10-16 g / ㎡, the coating amount of the UV reflection coating on the UV absorption layer 3 is 14-20 g / ㎡, the coating amount of the water-based silicone release agent on the UV reflection layer 2 is 2.8-3.8 g / ㎡, and the coating amount of the rubber-based glue on the isolation and anti-seepage layer 5 is 30-40 g / ㎡.

[0033] Further, the pH value of the ultraviolet reflection coating is 8.0 - 9.5, and it contains the following components by weight: 10 - 12 parts of nano-titanium dioxide, 12 - 14 parts of dispersant, 3 - 6 parts of modifier, and 4 - 6 parts of zinc oxide.

[0034] Preferably, the dispersant includes one or more of phosphate, sulfonate, and sulfate ester salt; the modifier includes one or more of magnesium oxide, silicon oxide, aluminum oxide, barium sulfate, and aluminate.

[0035] After preparing the required water-soluble styrene-acrylic emulsion, rubber-based glue, ultraviolet absorption coating, ultraviolet reflection coating, and water-based silicone release agent according to the above component ratios in advance, the following method is used to prepare the above-mentioned UV-resistant masking tape, and the method includes the following steps:

[0036] Step 1 Substrate anti-permeation treatment: Take the pre-prepared required water-soluble styrene-acrylic emulsion, and impregnate it on the bottom surface of the masking paper substrate by an impregnation method, and form an isolation and anti-seepage layer 5 after drying and curing;

[0037] Step 2 Coating the ultraviolet absorption coating: Take the pre-prepared required ultraviolet absorption coating containing nano-titanium dioxide and / or zinc oxide, and coat it on the upper surface of the masking paper substrate after anti-permeation treatment by a doctor blade coating method, and form an ultraviolet absorption layer 3 after drying and curing;

[0038] Step 3 Coating the ultraviolet reflection coating: Take the pre-prepared required ultraviolet reflection coating containing benzophenone and / or octyl dimethyl PABA and / or resorcinol monobenzoate, and coat it on the upper surface of the ultraviolet absorption layer 3 formed by curing by a doctor blade coating method, and form an ultraviolet reflection layer 2 after drying and curing;

[0039] Step 4 Coating the release agent: Take the pre-prepared required water-based silicone release agent, and coat it on the upper surface of the ultraviolet reflection layer 2 formed by curing by a doctor blade coating method, and form a release layer 1 after drying and curing;

[0040] Step 5 Gluing: Take the pre-prepared required rubber-based glue containing milled rubber, petroleum resin, naphthenic oil, antioxidant, and curing agent, and coat it on the bottom surface of the formed isolation and anti-seepage layer 5 by a doctor blade coating method, and form an adhesive layer 6 after drying and curing.

[0041] Preferably, for the water-soluble styrene-acrylic emulsion in Step 1, its preparation method is: by weight, take the styrene-acrylic stock solution with a solid content of 46 - 49% and dilute the styrene-acrylic stock solution with purified water according to a ratio of 1:(0.8 - 1.2), and stir evenly to obtain a water-soluble styrene-acrylic emulsion with a two-way anti-permeation function for standby.

[0042] Further, Step 1 specifically includes the following steps:

[0043] Step 1 (a): First, the water-soluble styrene-acrylic emulsion prepared in advance is placed in the impregnation tank of the coating machine;

[0044] Step 1(b): pulling the base paper of the masking paper substrate into the machine, conveying it to the impregnation tank through the guide roller of the machine, and immersing the bottom surface of the masking paper substrate in the styrene-acrylic emulsion, and using the water absorption of the masking paper substrate itself to absorb the water-soluble styrene-acrylic emulsion to form a thin film on the bottom surface of the masking paper substrate; in this process, the unwinding tension of the masking paper substrate is controlled at 2-3 kgf, the pulling speed is 180-195 m / min, and the absorption amount of the water-soluble styrene-acrylic emulsion absorbed by the masking paper substrate is controlled to be 50-60 g / ㎡ (wet amount);

[0045] Step 1(c): The masking paper with the water-soluble styrene acrylic emulsion film is sent to a ten-stage drying oven for drying and curing treatment, so that the film is cured on the bottom surface of the masking paper substrate to form a bidirectional anti-penetration isolation and anti-seepage layer 5 with water resistance, oil resistance, heat resistance and aging resistance, thereby completing the anti-penetration treatment of the masking paper substrate;

[0046] The drying temperatures of each drying section of the ten-stage drying oven are set to 178±2℃, 175±2℃, 170±2℃, 178±2℃, 181±2℃, 175±2℃, 161±2℃, 172±2℃, 176±2℃, 170±2℃, the paper surface temperature at the oven outlet is between 90 and 95℃, and the air volume is 200-250m 3 / min, wind speed 10-15m / s, the moisture content of the masking paper after drying is controlled between 4% and 6%, and the winding tension of the masking paper substrate is controlled between 20 and 25Kgf during this process.

[0047] Preferably, the preparation method of the ultraviolet absorption coating described in step 2 is as follows: by weight, 25 to 46 parts of acrylic acid, 32 to 55 parts of butyl acrylate, 3 to 5 parts of coupling agent, 2 to 6 parts of epoxy resin, and 150 to 1800 parts of toluene are mixed to form a coating base, and then 20 to 26 parts of benzophenone and / or 6 to 10 parts of octyl p-dimethylaminoformate and / or 3 to 5 parts of resorcinol monobenzoate are added to the prepared coating base and stirred evenly, and a sodium hydroxide solution with a mass fraction of 13 to 15% is added while stirring until the pH value is adjusted to 7.0 to 8.0 to obtain an ultraviolet absorption coating with UV absorption function.

[0048] Furthermore, step 2 specifically includes the following steps:

[0049] Step 2 (a): the prepared ultraviolet absorbing coating is placed in a material tank of a coating machine and coated by a first coating head;

[0050] Step 2(b): The masking paper after the anti-penetration treatment is pulled into the first coating head of the machine, and the ultraviolet absorbing coating is coated on the upper surface of the masking paper substrate by an anilox roller + doctor blade coating method, and the coating amount and uniformity are controlled by adjusting the gap between the doctor blade and the upper surface of the masking paper; during this process, the unwinding tension of the masking paper substrate is controlled at about 0.3-0.8 kgf, the pulling speed is 90-95 m / min, and the coating amount of the ultraviolet absorbing coating is controlled between 10-16 g / ㎡;

[0051] Step 2(c): The masking paper coated with a layer of ultraviolet absorbing coating is sent to a four-stage drying oven A through a machine for drying and curing, so that the coated ultraviolet absorbing coating is cured on the upper surface of the masking paper substrate to form an ultraviolet absorbing layer 3 with UV absorbing function;

[0052] The drying temperatures of each drying section of the four-stage drying oven A are set to 70±5℃, 80±5℃, 90±5℃, 90±5℃, respectively. The paper surface temperature at the oven outlet is between 83 and 87℃, and the air volume is 150 to 200m 3 / min, wind speed 8~12m / s.

[0053] Preferably, the preparation method of the ultraviolet reflective coating described in step 3 is as follows: by weight, 25 to 46 parts of acrylic acid, 32 to 55 parts of butyl acrylate, 3 to 5 parts of coupling agent, 2 to 6 parts of epoxy resin, and 150 to 1800 parts of toluene are mixed to form a coating base, and then 8 to 16 parts of nano titanium dioxide and / or 3 to 9 parts of zinc oxide are added to the prepared coating base and stirred evenly, and a sodium hydroxide solution with a mass fraction of 13 to 15% is added while stirring until the pH value is adjusted to 8.0 to 9.5, so as to obtain an ultraviolet reflective coating with UV reflection function.

[0054] Furthermore, step 3 specifically includes the following steps:

[0055] Step 3 (a): the prepared ultraviolet reflective coating is placed in a material tank of a coating machine and coated by a second coating head;

[0056] Step 3(b): Pull the masking paper with the UV absorption layer into the second coating head of the machine, and apply the UV reflective coating on the upper surface of the UV absorption layer 3 by anilox roller + doctor blade coating, and control the coating amount and uniformity by adjusting the gap between the doctor blade and the upper surface of the masking paper; in this process, the unwinding tension of the masking paper substrate is controlled at about 0.3-0.8 kgf, the pulling speed is 90-95 m / min, and the coating amount of the UV absorption coating is controlled between 14-20 g / ㎡;

[0057] Step 3(c): The masking paper coated with a layer of ultraviolet absorption coating is fed into a four-stage oven B by a machine for drying and curing treatment, so that the coated ultraviolet reflection coating is cured on the upper surface of the ultraviolet absorption layer to form an ultraviolet reflection layer 2 with UV reflection function;

[0058] The drying temperatures of each drying section of the four-stage oven B are set to 70±5°C, 80±5°C, 90±5°C, 90±5°C in sequence. The paper surface temperature at the oven outlet is between 82 and 85°C, the air volume is 150 - 200m 3 / min, the wind speed is 8 - 12m / s, and the dryness is controlled between 4 and 6%;

[0059] Step 3(d): The masking paper that has been coated twice (i.e., coated with ultraviolet absorption coating and ultraviolet reflection coating) and dried in a gradient manner enters the winding rack for winding. During this process, the winding tension of the masking paper substrate is controlled at about 15 - 20Kgf.

[0060] Preferably, in the ultraviolet reflection coating described in step 3, on the basis of the coating base material with the above component ratio, 10 - 12 parts of nano-titanium dioxide, 12 - 14 parts of dispersant, 3 - 6 parts of modifier, and 4 - 6 parts of zinc oxide can be added and stirred evenly. While stirring, a sodium hydroxide solution with a mass fraction of 13 - 15% is added until the pH value is adjusted to 8.0 - 9.5 to obtain a dispersed and modified ultraviolet reflection coating.

[0061] Among them, the dispersant is selected from one or more of phosphates, sulfonates, and sulfate esters, and the modifier is selected from one or more of magnesium oxide, silicon oxide, aluminum oxide, barium sulfate, and aluminate ester.

[0062] Preferably, the preparation method of the aqueous silicone release agent described in step 4 is: by weight, take an aqueous silicone stock solution with a solid content of 35 - 40% and dilute the aqueous silicone stock solution with purified water according to a ratio of 1:(2.2 - 3.2), stir evenly, and prepare the aqueous silicone release agent for use.

[0063] Furthermore, step 4 specifically includes the following steps:

[0064] Step 4(a): The prepared above-mentioned aqueous silicone release agent is pre-placed in the trough of the coater and coated by a silicon coating head;

[0065] Step 4(b): Pull the masking paper with the UV reflective layer into the silicon coating head of the machine, and apply the water-based silicone release agent on the upper surface of the UV reflective layer 2 by anilox roller + doctor blade coating, and control the coating amount and uniformity by adjusting the gap between the doctor blade and the upper surface of the masking paper; in this process, the unwinding tension of the masking paper substrate is controlled at about 2 to 4 kgf, the pulling speed is 180 to 195 m / min, and the coating amount of the water-based silicone release agent is controlled to be between 2.8 and 3.8 g / ㎡;

[0066] Step 4(c): The masking paper coated with a layer of water-based silicone release agent is sent to a four-stage drying oven C for drying and curing, so that the coated water-based silicone release agent is cured on the upper surface of the ultraviolet reflective layer to form a release layer 1 with an anti-sticking function, which is convenient for the masking tape to be unwound smoothly when it is used later;

[0067] The drying temperatures of the four-stage drying oven C are set to 165±3℃, 165±3℃, 170±3℃, 170±3℃, respectively. The paper surface temperature at the oven outlet is between 105 and 115℃, and the air volume is 200 to 250m 3 / min, wind speed 10-15m / s, the moisture content of the paper after drying is controlled between 4% and 6%;

[0068] Step 4 (d): After being coated with release agent and gradient dried, the masking paper enters the winding frame for winding. During this process, the winding tension of the masking paper substrate is controlled at about 10 to 15 kgf.

[0069] Preferably, the rubber type glue described in step 5 is prepared by: taking 28 to 33 parts of 112 series methyl vinyl silicone rubber by weight, refining and melting, adding 4 to 6 parts of C5 petroleum resin and 0.7 to 1.3 parts of cyclohexane oil, stirring and heating, maintaining the colloid temperature at about 50 to 65°C, stirring for 2 to 4 hours to make the colloid have better viscosity, and then adding 65 to 70 parts of toluene and 1.0 to 1.5 parts of phosphite antioxidant, stirring for 3 to 6 hours to make the colloid have better aging resistance, adding 0.4 to 0.7 parts of amino curing agent before coating the colloid, stirring evenly to obtain a rubber type glue with a viscosity between 75,000 and 85,000 and a solid content of about 41% ± 2 for standby use.

[0070] Furthermore, step 5 specifically includes the following steps:

[0071] Step 5 (a): the rubber-type glue prepared is placed in a material tank of a coating machine and coated by a coating head;

[0072] Step 5(b): Feed the masking paper with the release layer 1 formed thereon into the coating head of the machine, and coat the bottom surface of the isolation and anti-seepage layer 5 with the rubber-based glue by means of an anilox roll + knife coating method. Control the coating amount and uniformity by adjusting the gap between the doctor blade and the lower surface of the masking paper; during this process, control the unwinding tension of the masking paper substrate at about 0.8 - 1.5 Kgf, the traction speed at 90 - 110 m / min, and control the coating amount of the rubber-based glue between 30 - 40 g / ㎡;

[0073] Step 5(c): Feed the masking paper coated with a layer of rubber-based glue into a thirteen-section oven through the machine for drying and curing treatment, so that the coated rubber-based glue cures on the lower surface of the isolation and anti-seepage layer to form an adhesive layer 6 with high viscosity, aging resistance, and good cohesion;

[0074] Set the drying temperatures of the respective drying sections of the thirteen-section oven to 80 ± 5°C, 90 ± 5°C, 100 ± 5°C, 110 ± 5°C, 110 ± 5°C, 120 ± 5°C, 125 ± 5°C, 125 ± 5°C, 130 ± 5°C, 120 ± 5°C, 90 ± 5°C, 80 ± 5°C, 60 ± 5°C in sequence. The paper surface temperature at the oven outlet is between 65 - 75°C, the air volume is 200 - 250 m 3 / min, the wind speed is 10 - 15 m / s, and control the moisture content of the dried paper between 3 - 7%;

[0075] Step 5(d): Feed the masking paper that has been coated with glue and dried in a gradient manner into the winding rack for winding. During this process, control the winding tension of the masking paper substrate at about 20 - 25 Kgf.

[0076] After the operations in the above steps 1 - 5 are completed, the master roll of masking paper can be slit as required to obtain the finished masking paper tape.

[0077] Prepare the required water-based silicone release agent, ultraviolet reflection coating, ultraviolet absorption coating, water-soluble styrene-acrylic emulsion, and rubber-based glue respectively according to the component ratios listed in Table 1 and Table 2 below, and then obtain the finished masking paper tape products of Examples 1 - 8 according to the specific operation methods of the above steps 1 - 5.

[0078] Table 1: Component ratio table of Examples 1 - 4

[0079]

[0080]

[0081] Table 2: Component ratio table of Examples 5 - 8

[0082]

[0083]

[0084]

[0085] The required water-based silicone release agent, UV reflective coating, UV absorbing coating, water-soluble styrene acrylic emulsion and rubber-type glue were prepared according to the component ratios listed in Table 3, and then the finished masking tapes of Comparative Examples 1-4 were prepared by referring to the operating methods of steps 1-5 above.

[0086] Among them, compared with the components and manufacturing method of the above-mentioned Example 1, the main difference of the masking tape of Comparative Example 1 is that the ultraviolet absorbing coating and the ultraviolet reflecting coating are first mixed and stirred evenly, and then the mixed coating is coated on the upper surface of the masking paper substrate at one time according to the above-mentioned coating method, and after drying and curing, an anti-UV layer with both ultraviolet reflecting function and ultraviolet absorbing function is formed.

[0087] Compared with the components and manufacturing method of the above-mentioned Example 2, the main difference of the masking tape of Comparative Example 2 is that the ultraviolet reflective coating is first coated on the upper surface of the masking paper substrate, and the ultraviolet reflective layer is formed after drying and curing, and then the ultraviolet absorbing coating is coated on the formed ultraviolet reflective layer, and the ultraviolet absorbing layer is formed after drying and curing, and then the water-based silicone release agent is coated on the formed ultraviolet absorbing layer, and the release layer is formed after drying and curing.

[0088] Compared with the components and manufacturing method of the above-mentioned Example 3, the main difference of the masking tape of Comparative Example 3 is that the masking paper substrate is not subjected to anti-penetration treatment, the isolation anti-seepage layer is eliminated, and the rubber-type glue is directly coated on the lower bottom surface of the masking paper substrate.

[0089] Compared with the components and manufacturing method of the above-mentioned Example 4, the main difference of the masking tape manufacturing method of Comparative Example 4 is that the component ratio of the rubber-type glue is adjusted and the antioxidant and curing agent therein are removed.

[0090] Table 3: Group distribution ratio table of comparative examples 1-4

[0091]

[0092]

[0093] The masking tape products of Examples 1-8 and Comparative Examples 1-4 were subjected to UV resistance application testing. The specific test method was to randomly cut 3 test segments of the same size from each masking tape prepared in the examples and comparative examples, and mark them as test segment a, test segment b, and test segment c respectively. The 3 test segments obtained from each example and comparative example tape product were arranged and pasted on the surface-cleaned stainless steel plate in order from top to bottom, and at the same time, the test segments of the same serial number in each example and comparative example were kept at the same horizontal position, and a 1 kg pressure roller was used to repeatedly roll each test segment to make it completely adhere. The above actions were repeated four times to obtain four stainless steel plates 1-4 with the test segments attached. Then, the four stainless steel plates with the test segments attached were placed flat outdoors without any obstacles, so that each test segment was directly irradiated by sunlight. After 7 / 10 / 20 / 30 days, the masking tape on one of the stainless steel plates was removed respectively and the residual glue situation was checked, and the residual glue area was counted. The test results are shown in Tables 4 to 5.

[0094] Table 4: Statistical table of the residual glue area of the test segments of each masking tape of Examples 1-4 and Comparative Examples 1-4 removed after 7 / 10 / 20 / 30 days

[0095]

[0096]

[0097] Table 5: Statistical table of the residual glue area of the test segments of each masking tape of Examples 5-8 removed after 7 / 10 / 20 / 30 days

[0098]

[0099]

[0100] The following is a comparison of the use effects of the finished masking tape products of each example and comparative example to illustrate the component characteristics and beneficial effects of each functional structure layer of the masking tape of the present invention.

[0101] From the statistical results in Table 4, it can be seen that there is no residual glue phenomenon when the masking tapes of Examples 1-4 are removed after being attached for 7-20 days, and there is only a small amount of residual glue when they are removed after being attached for 30 days. This proves that the masking tape of the present invention has excellent UV resistance compared with the prior art. Its functional layer structure design of reflecting and absorbing ultraviolet rays layer by layer, and the optimized component ratio can prevent ultraviolet rays from projecting onto the adhesive layer to damage the molecular chain structure of the glue to the greatest extent. At the same time, the existence of the isolation and anti-seepage layer can also play a two-way anti-seepage role, preventing the substances in each functional structure layer on the upper and lower sides of the masking tape base material layer from penetrating each other, ensuring the UV resistance of the masking tape of the present invention.

[0102] Meanwhile, from the test results of Example 1 and Comparative Example 1, it can be seen that compared with the prior art method of mixing ultraviolet absorption components and ultraviolet reflection components in an anti-UV coating simultaneously, coating and curing to form a mixed anti-UV layer, the present invention separates the ultraviolet absorption components and ultraviolet reflection components, and separately prepares an ultraviolet absorption coating and an ultraviolet reflection coating. After coating, drying and curing, an ultraviolet reflection layer and an ultraviolet absorption layer with obvious boundaries and distinct functions are formed. By reflecting first and then absorbing, ultraviolet rays are eliminated step by step and layer by layer, and the anti-UV effect is better. There is no residual glue after long-term use.

[0103] From the test results of Example 2 and Comparative Example 2, it can be seen that the ultraviolet reflection layer and the ultraviolet absorption layer of the masking tape of the present invention cannot be hierarchically swapped. Only by reflecting first and then absorbing when ultraviolet rays are incident can the ultraviolet rays be completely blocked.

[0104] From the test results of Example 3 and Comparative Example 3, it can be seen that the isolation and anti-seepage layer on the bottom surface of the masking tape of the present invention and the ultraviolet absorption layer and ultraviolet reflection layer on the upper surface of the masking tape play a synergistic anti-ultraviolet coupling and superposition effect. By using the two-way anti-seepage effect of the isolation and anti-seepage layer, the component penetration between the anti-UV coating and the rubber-based glue is avoided, and the adverse effects of two-way material penetration on the adhesive layer, ultraviolet absorption layer and ultraviolet reflection layer are avoided, ensuring the UV resistance of the masking tape of the present invention.

[0105] From the test results of Example 4 and Comparative Example 4, it can be seen that the adhesive layer of the masking tape of the present invention optimizes the glue components. By introducing petroleum resin and naphthenic oil, the glue has stronger viscosity and uniformity; the added antioxidant can improve the aging resistance of the glue, enabling it to withstand high temperatures of 80°C and low temperatures of -20°C without denaturation and aging, ensuring the reliability of the glue in use; in addition, the specific proportion of curing agent added before coating the glue of the present invention significantly improves the cohesion of the glue, enabling the adhesive layer to cooperate with the above-mentioned isolation and anti-seepage layer, ultraviolet absorption layer and ultraviolet reflection layer, realizing the synergistic superposition effect of multiple anti-ultraviolet functions, and further improving the anti-UV property of the masking tape of the present invention.

[0106] In addition, from the test results of Examples 1-4 and Examples 5-8 in Table 4 and Table 5, it can be seen that by optimizing and improving the components of the ultraviolet reflection layer, the anti-UV property of the tape can be further improved. The added modifier in the ultraviolet reflection layer can significantly improve the photocatalytic activity of nano-titanium dioxide, reduce the degradation degree of organic substances in the coating by nano-titanium dioxide under light, prevent the coating from yellowing, powdering and peeling, ensure the reliability of the masking tape of the present invention in use, and at the same time, the added dispersant can further promote the dispersion degree and stability of nano-titanium dioxide and zinc oxide in the coating, ensuring the effect of the ultraviolet reflection layer in efficiently reflecting ultraviolet rays, and further improving the anti-UV property of the masking tape of the present invention.

[0107] In summary, compared with the prior art, the present invention has the following beneficial effects:

[0108] 1. The anti-UV functional layer of the masking tape of the present invention is divided into an upper UV reflection layer and a lower UV absorption layer. During the ultraviolet irradiation process, the upper UV reflection layer has components of nano-titanium dioxide and / or zinc oxide capable of reflecting ultraviolet rays. Therefore, it can evenly reflect up to 80% of the ultraviolet rays, thus blocking the vast majority of ultraviolet rays. At the same time, the lower UV absorption layer has components of benzophenone and / or octyl dimethylaminobenzoate and / or resorcinol monobenzoate capable of absorbing ultraviolet rays. Therefore, it can evenly, fully and thoroughly absorb the remaining ultraviolet rays that penetrate the reflection layer and convert them into heat for consumption, thereby achieving the purpose of gradually and layer-by-layer filtering out ultraviolet rays in the present invention, playing an excellent ultraviolet shielding role, blocking the ultraviolet rays from penetrating the masking paper substrate layer and damaging the molecular chain structure of the adhesive layer, and effectively solving the problem of residual glue after the masking tape is removed after long-term use.

[0109] 2. The present invention optimizes the composition ratio of the anti-UV components of the UV reflection layer and the UV absorption layer, enabling the UV reflection layer to reflect the vast majority of the incident ultraviolet rays to the greatest extent, reducing the difficulty for the UV absorption layer to thoroughly filter out the penetrated ultraviolet rays, ensuring the high anti-UV performance of the masking tape of the present invention, and avoiding the occurrence of the residual glue problem. At the same time, the optimization of the above composition ratio can also reduce the coating amounts of the UV reflection coating and the UV absorption coating to the greatest extent, reduce the production cost of the masking tape, and improve the market competitiveness of the products of the present invention.

[0110] 3. An isolation and anti-seepage layer is provided on the bottom surface of the masking paper substrate layer of the present invention. This isolation and anti-seepage layer is a functional structure layer formed by curing water-soluble styrene-acrylic emulsion on the bottom surface of the masking paper substrate layer, and has excellent properties of water resistance, oil resistance, heat resistance and aging resistance, enabling the masking paper of the present invention to have excellent anti-permeability and play a good two-way barrier role. During long-term use, the glue in the adhesive layer will not penetrate upward to the upper surface of the masking paper substrate layer, and at the same time, it can also block the UV absorption coating, UV reflection coating and release agent on the upper surface of the masking paper substrate layer from penetrating downward into the adhesive layer and damaging the molecular chain structure of the glue.

[0111] 4. The masking tape of the present invention optimizes the component ratio of the adhesive layer. By adding honey-refined rubber, petroleum resin and naphthenic oil, the glue has better adhesiveness. At the same time, the added antioxidant improves the aging resistance of the glue, enabling it to withstand high temperatures of about 80°C and low temperatures of about -20°C. In addition, the curing agent added to the glue can significantly improve the cohesion of the glue, further enhancing the UV resistance of the glue. Cooperating with the above-mentioned isolation and anti-seepage layer, UV absorption layer and UV reflection layer, it plays a synergistic effect, solving the problem of residual glue when the masking tape is removed after long-term outdoor irradiation.

[0112] In addition, the manufacturing method of the anti-UV masking tape of the present invention has a simple process flow and is easy to implement, reducing the production and manufacturing cost of the masking tape, and ensuring the product quality of the masking tape, which is beneficial to the market promotion of the product.

[0113] The above embodiments are only for clearly expressing the technical solutions of the present invention, and are not limitations on the implementation manners of the present invention. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention, but these corresponding changes and deformations should all fall within the protection scope of the present invention.

Claims

1. An anti-UV masking tape, which includes a release layer, a masking paper substrate layer, and an adhesive layer from top to bottom. It is characterized in that it further includes an ultraviolet absorption layer formed by curing an ultraviolet absorption coating on the upper surface of the masking paper substrate layer, and an ultraviolet reflection layer formed by curing an ultraviolet reflection coating on the upper surface of the ultraviolet absorption layer. The release layer is provided on the ultraviolet reflection layer, and any two adjacent layers are self-adhered and fixed. An isolation and anti-seepage layer formed by impregnating the lower bottom surface of the masking paper substrate layer with a water-soluble styrene-acrylic emulsion and curing is also provided between the adhesive layer and the masking paper substrate layer. The absorption amount of the masking paper substrate layer for the water-soluble styrene-acrylic emulsion is 50-60 g / ㎡. Among them, the ultraviolet absorption coating contains the following components by weight: 20-26 parts of benzophenone and / or 6-10 parts of octyl dimethylaminobenzoate and / or 3-5 parts of resorcinol monobenzoate; the ultraviolet reflection coating contains the following components by weight: 8-16 parts of nano-titanium dioxide and / or 3-9 parts of zinc oxide. The preparation method of the water-soluble styrene-acrylic emulsion is: by weight, take a styrene-acrylic stock solution with a solid content of 46-49% and dilute the styrene-acrylic stock solution with purified water according to a ratio of 1:0.8-1.2, and stir evenly to obtain a water-soluble styrene-acrylic emulsion with a two-way anti-permeation function. The adhesive layer is formed by coating a rubber-based glue on the lower bottom surface of the isolation and anti-seepage layer, and the rubber-based glue contains the following components by weight: 28-33 parts of milled rubber, 4-6 parts of petroleum resin, 0.7-1.3 parts of naphthenic oil, 1.0-1.5 parts of phosphite antioxidant, and 0.4-0.7 parts of curing agent.

2. An anti-UV masking tape according to claim 1, It is characterized in that: The coating amount of the rubber-based glue is 30-40 g / ㎡.

3. An anti-UV masking tape according to claim 1, It is characterized in that: The coating amount of the ultraviolet reflection coating is 14-20 g / ㎡, and the coating amount of the ultraviolet absorption coating is 10-16 g / ㎡.

4. An anti-UV masking tape according to claim 1, It is characterized in that: The release layer is formed by coating an aqueous silicone release agent on the upper surface of the ultraviolet reflection layer, and the coating amount of the aqueous silicone release agent is 2.8-3.8 g / ㎡.

5. An anti-UV masking tape according to claim 1, It is characterized in that: The pH value of the ultraviolet reflection coating is 8.0-9.5, and it contains the following components by weight: 10-12 parts of nano-titanium dioxide, 12-14 parts of dispersant, 3-6 parts of modifier, and 4-6 parts of zinc oxide.

6. An anti-UV masking tape according to claim 5, It is characterized in that: The dispersant is selected from one or more of phosphates, sulfonates, and sulfate esters; the modifier is selected from one or more of magnesium oxide, silicon oxide, aluminum oxide, barium sulfate, and aluminate.

7. A manufacturing method of an anti-UV masking tape according to any one of claims 1-6, It is characterized in that the method comprises the following steps: Step 1, substrate anti-permeation treatment: Take the required pre-prepared water-soluble styrene-acrylic emulsion, and impregnate it on the bottom surface of the masking paper substrate by impregnation method. After drying and curing, an isolation and anti-seepage layer is formed; Step 2, coating UV-absorbing coating: Take the required pre-prepared UV-absorbing coating containing benzophenone and / or octyl dimethyl aminobenzoate and / or resorcinol monobenzoate, and coat it on the upper surface of the masking paper substrate after anti-permeation treatment by scraping method. After drying and curing, a UV-absorbing layer is formed; Step 3, coating UV-reflective coating: Take the required pre-prepared UV-reflective coating containing nano-titanium dioxide and / or zinc oxide, and coat it on the upper surface of the cured UV-absorbing layer by scraping method. After drying and curing, a UV-reflective layer is formed; Step 4, coating release agent: Take the required pre-prepared release agent, and coat it on the upper surface of the cured UV-reflective layer by scraping method. After drying and curing, a release layer is formed; Step 5, gluing: Take the required pre-prepared rubber-based glue containing kneaded rubber, petroleum resin, naphthenic oil, antioxidant and curing agent, and coat it on the bottom surface of the formed isolation and anti-seepage layer by scraping method. After drying and curing, an adhesive layer is formed.

8. The manufacturing method of a UV-resistant masking tape according to claim 7, it is characterized in that the drying processes in the above steps 1 to 5 are respectively carried out by a segmented dryer for gradient drying.

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