Production process of high-viscosity self-adhesive paper

Abstract

The invention relates to the field of self-adhesive paper, and particularly discloses a high-viscosity self-adhesive paper production process which comprises the following steps: S1, providing a surface material and bottom paper, performing corona treatment on the surface material to improve the surface activity, forming a release layer on the surface of the bottom paper, and coating the back surface of the surface material with an antistatic functional layer; through construction of a three-dimensional through pore structure and a synergistic effect of the composite cross-linking auxiliary agent, the comprehensive bonding performance of the self-adhesive paper is effectively improved, a through pore network which is high in stability and uniform in distribution is formed through interface permeation and chemical bonding of the micron-sized inorganic powder and a glue solution, the effective bonding area of a glue layer is remarkably increased, and the service life of the self-adhesive paper is prolonged. Meanwhile, balanced improvement of initial adhesion, persistent adhesion and peel strength is achieved, a composite field regulation and control means of low-frequency vibration and an alternating magnetic field is adopted, interface defects are effectively eliminated, pore connectivity is optimized, and integrity and reliability of an adhesive layer structure are ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of self-adhesive paper, in particular to a production process of high-adhesion self-adhesive paper. BACKGROUND

[0002] In the production field of self-adhesive paper, traditional process usually adopts acrylate pressure-sensitive adhesive as the adhesive layer, and adjusts the glue solution formula or adds fillers to improve adhesion. However, these methods often have difficulty in balancing the initial adhesion, holding adhesion and peeling strength, and are prone to problems such as residual glue and aging performance decline. In addition, the glue layer formed by conventional coating process is usually of dense structure, and the specific surface area is limited, which restricts the further improvement of the bonding effect. Although there are attempts to introduce microporous structure to enhance adhesion in the prior art, there are defects such as uneven pore distribution, poor structure stability or weak bonding force with the substrate, resulting in poor actual application effect. At the same time, ordinary self-adhesive paper is prone to performance attenuation in high temperature and high humidity environment, and has insufficient weather resistance, which is difficult to meet the strict requirements of high-end labels, outdoor signs and other application scenarios for durable bonding performance. SUMMARY

[0003] The purpose of the present application is to provide a production process of high-adhesion self-adhesive paper to overcome the above-mentioned defects in the prior art.

[0004] According to the production process of high-adhesion self-adhesive paper of the present application, the following steps are included: S1, providing a face material and a backing paper, performing corona treatment on the face material to improve surface activity, forming a release layer on the surface of the backing paper, and coating an antistatic functional layer on the back of the face material; S2, coating a mixed glue solution on the surface of the face material, specifically including: S2.1, preparing an acrylate pressure-sensitive adhesive base solution, including a combination of acrylate main glue, multifunctional crosslinking agent and catalyst; S2.2, adding a composite crosslinking aid to the acrylate pressure-sensitive adhesive base solution obtained in step S2.1 to obtain a mixed glue solution, the composite crosslinking aid being formed by compounding a water-soluble polymer containing a reactive functional group, a polyaziridine compound and an organic silicon modifier; S2.3, uniformly coating the mixed glue solution obtained in step S2.2 on the back of the face material; S3, constructing a glue layer with a three-dimensional through-pore structure on the back of the face material, specifically including: S3.1, during the coating process of the mixed glue solution, directing the micron-sized inorganic powder to be scattered on the surface of the mixed glue solution by a high-pressure airflow jetting device; S3.2, transferring the face material coated with micron-sized inorganic powder to a closed environment with controllable temperature and humidity, so that the micron-sized inorganic powder and the mixed glue solution undergo interfacial penetration to form a continuous pore network with the powder as the skeleton; S3.3, low-frequency vibration field is applied to the mixed glue liquid after the fusion of the micron-sized inorganic powder, the uniform distribution of pores is promoted, and the interface bubbles are eliminated, so that a glue layer with a three-dimensional through-pore structure is obtained; S4, the face material treated in S3 is controlled in thickness by a coating device, uniformity data of coating is fed back in real time by an optical detection system, the glue-coated face material is compounded with a release layer of a base paper, and after integration by an elastic compression roller, a segmented drying procedure is entered; S5, a weather-resistant protective coating is applied to the surface of the dried adhesive paper, the coating contains nano-enhanced particles and a polymer dispersion medium, and is cold-pressed and shaped by a multi-stage tension control device to eliminate interlayer stress; S6, the adhesive paper after shaping is tested for adhesive index, and after confirmation of meeting the standard, it is slit and wound.

[0005] In the above technical solution, the acrylate main glue in step S2.1 is composed of 50-70 parts of isooctyl acrylate, 15-25 parts of butyl acrylate, and 1-3 parts of glycidyl methacrylate; The multifunctional crosslinking agent is a mixture of trimethylolpropane triacrylate and hexanediol diacrylate, and the mass ratio of the two is (1:0.5)-(1:1.2) In the above technical solution, the compounding process of the composite crosslinking aid in step S2.2 includes: SS1, first, 10-15 parts of the water-soluble polymer containing reactive functional groups are premixed with 5-8 parts of a silicone modifier in an inert atmosphere, a cosolvent is added during premixing, and the temperature is controlled at 40-60°C; SS2, then 8-12 parts of a polyaziridine compound are added dropwise while maintaining a shear rate threshold; SS3, the final mixture is treated by ultrasonic defoaming.

[0006] In the above technical solution, the mixed glue liquid coating in step S2.3 adopts slit extrusion coating, and the coating head is equipped with a temperature gradient control module to make the glue liquid viscosity decrease along the coating direction.

[0007] In the above technical solution, the high-pressure airflow injection device in step S3.1 meets: The airflow contains a mixture of compressed air treated by dehumidification and atomized organic solvent vapor; An electrostatic field is applied immediately after the powder is scattered to make the powder directional arrangement.

[0008] In the above technical solution, the interface penetration process in step S3.2 is realized by the following control: An oxygen concentration suppression unit is arranged in a closed environment; The base material running speed is dynamically coupled with the temperature and humidity change rate; The online microscopic imaging system is used to monitor the pore nucleation state.

[0009] In the technical solution, the low-frequency vibration field in step S3.3 is applied in the initial curing stage of the mixed glue solution and is terminated before the critical gel point, and the low-frequency vibration field satisfies the following conditions during implementation: The vibration frequency decreases with the degree of curing of the glue layer; The vertical surface material direction is superimposed with an alternating magnetic field; The glue solution is at the critical gel point when the vibration is terminated.

[0010] In the technical solution, the formation of the three-dimensional through-pore structure needs to satisfy the following conditions: The surface of the micron-sized inorganic powder is modified with active groups that react with the crosslinking aid; The pore network is gradiently distributed in the thickness direction of the glue layer; The maximum pore size of the pore network does not exceed 1 / 2 of the thickness of the glue layer.

[0011] In the technical solution, the surface of the micron-sized inorganic powder is pretreated with a silane coupling agent.

[0012] The beneficial effects of the present application are as follows: 1. The present application effectively improves the comprehensive bonding performance of the adhesive paper by constructing a three-dimensional through-pore structure and the synergistic effect of the composite crosslinking aid.

[0013] 2. The micron-sized inorganic powder and the glue solution form a stable and uniformly distributed through-pore network through interfacial penetration and chemical bonding, significantly increasing the effective bonding area of the glue layer, and achieving balanced improvement in initial adhesion, holding adhesion, and peel strength.

[0014] 3. The use of a low-frequency vibration and alternating magnetic field composite field control method effectively eliminates interface defects and optimizes pore connectivity, ensuring the integrity and reliability of the glue layer structure.

[0015] 4. The combination of a weather-resistant protective coating and a cold-pressing shaping process significantly enhances the product's resistance to ultraviolet aging, moisture resistance, and pollution resistance, extending the service life.

[0016] 5. The entire production process is designed reasonably, with close connection between each step, realizing online monitoring and dynamic control, and ensuring the consistency and stability of product quality. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a flowchart of a high-adhesion adhesive paper production process provided by the present application; Figure 2 is a flowchart of a process of coating a mixed glue solution on the surface of the surface material in the high-adhesion adhesive paper production process provided by the present application; Figure 3 is a flow chart of the adhesive layer of the three-dimensional through-pore structure constructed on the back of the face material in the production process of the high-adhesion adhesive paper provided by the present application. DETAILED DESCRIPTION

[0018] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the drawings shown in the accompanying drawings, and are only for the convenience of describing the simplified description of the present application, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. Figure 1 The orientation or positional relationship shown is only for the convenience of describing the simplified description of the present application, and does not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0019] In order to make the purpose and advantages of the present application more clear and explicit, the present application will be specifically described below in combination with examples, and it should be understood that the following text is only used to describe one or several specific embodiments of the present application, and does not strictly limit the specific protection range requested by the present application, and as used herein, the terms up and down and left and right are not limited to their strict geometric definitions, but include reasonable and inconsistent tolerances for machining or human error, and the specific features of the high-adhesion adhesive paper production process are described in detail below: An embodiment of the present application: Referring to Figure 1 , the present application provides a high-adhesion adhesive paper production process, comprising the following steps: S1, providing a face material and a base paper, performing corona treatment on the face material to improve the surface activity, forming a release layer on the surface of the base paper, and simultaneously coating an antistatic functional layer on the back of the face material; In this embodiment, after providing the face material and the base paper, the face material is first subjected to corona treatment: a high-frequency high-voltage generator is used to form an ionized air layer between the corona roller and the face material; At the same time, the release layer is coated on the surface of the base paper: the silicone release agent is applied to the base paper by a transfer coating machine with a screen roller, and then dried by 80-100℃ hot air step drying (low temperature first and then high temperature in different zones), to form a release layer; Synchronously, the antistatic functional layer is coated on the back of the face material: the water-based dispersion liquid containing conductive polymer PEDOT:PSS and polyurethane adhesive are mixed in a mass ratio of 1:(0.3-0.5), and applied by micro-gravure coating, and then dried by 60-70℃ infrared drying to form an antistatic layer, with a surface resistivity ≤10 9 Ω / sq, and an adhesive force ≥4B with the subsequent adhesive layer.

[0020] As shown in Figure 2 S2, a mixed adhesive solution is coated on the surface of the face material, specifically including: S2.1, preparing an acrylate pressure-sensitive adhesive base solution, comprising a combination of an acrylate main adhesive, a multifunctional crosslinking agent, and a catalyst; Specifically, the acrylate main adhesive in step S2.1 is composed of 50-70 parts of isooctyl acrylate, 15-25 parts of butyl acrylate, and 1-3 parts of glycidyl methacrylate; The multifunctional crosslinking agent is a mixture of trimethylolpropane triacrylate and hexanediol diacrylate, with a mass ratio of (1:0.5)-(1:1.2) In this embodiment, when preparing the acrylate pressure-sensitive adhesive base solution, first, 50-70 parts of isooctyl acrylate, 15-25 parts of butyl acrylate, and 1-3 parts of glycidyl methacrylate are added to a reaction kettle, the air is replaced with nitrogen, and then the temperature is raised to 75-80°C, and the stirring speed is set to 200-400 rpm to form a monomer mixture; Subsequently, 0.5-1 parts of a free radical initiator (azobisisobutyronitrile / AIBN) ethanol solution (concentration 5-10%) is added dropwise, the dropwise addition speed is controlled at 1-2 mL / min, after the dropwise addition is completed, the temperature is kept at 80-85°C for 3-5 hours, and an acrylate main adhesive with a viscosity average molecular weight of 300-500 kg / mol is generated; After the system cools down to below 50°C, a multifunctional crosslinking agent is added, which is a mixture of trimethylolpropane triacrylate (TMPTA) and hexanediol diacrylate (HDDA) with a mass ratio of (1:0.5)-(1:1.2), and the addition amount is 3%-8% of the total weight of the monomers, 0.5-2 parts of an organic tin catalyst (dibutyltin dilaurate) is added synchronously, and high-speed dispersion is performed for 20-40 minutes, finally obtaining a uniform acrylate pressure-sensitive adhesive base solution with a viscosity of 8000-12000 (25°C), a solid content of 85±2%, and a gel fraction of >85% (determined by toluene extraction).

[0021] S2.2, adding a composite crosslinking aid to the acrylate pressure-sensitive adhesive base solution obtained in step S2.1 to obtain a mixed adhesive solution, the composite crosslinking aid being formed by compounding a water-soluble polymer containing reactive functional groups, a polyaziridine compound, and an organic silicon modifier; Specifically, the compounding process of the composite crosslinking aid in step S2.2 includes: SS1, first, 10-15 parts of a water-soluble polymer containing reactive functional groups and 5-8 parts of an organic silicon modifier are premixed under an inert atmosphere, a cosolvent is added during premixing, and the temperature is controlled at 40-60°C; In this embodiment, when adding a complex crosslinking aid to the obtained acrylic ester pressure-sensitive adhesive base solution in S2.1, first, the aid is compounded: in an inert atmosphere reaction kettle (nitrogen purity ≥ 99.99%, oxygen content < 50 ppm), first, 10-15 parts of a water-soluble polymer containing an oxazoline functional group (MPEG-MA copolymer, molecular weight 3000-5000 g / mol) and 5-8 parts of a vinyl-terminated linear organosilicon modifier (viscosity 800-1200 ) are added, a co-solvent (a mixture of ethanol and deionized water in a mass ratio of 1:1, the amount of which is 30-50% of the total weight of the polymer) is simultaneously injected, the system is warmed to 40-60°C and pre-mixed with an anchor stirrer to form a translucent homogeneous liquid; Then, 8-12 parts of a trifunctional aziridine compound (pentaerythritol tris(3-aziridinyl) propionate) is added dropwise through a micro-injection pump, the dropwise addition speed is controlled to be 1-2 mL / min, and the shear rate is maintained at 800-1000 s -1 and the temperature fluctuation is ≤±2°C through jacket cooling; After the dropwise addition is completed, the stirring is continued for 10 minutes, and finally the mixture is transferred to an ultrasonic reactor for defoaming treatment for 5-8 minutes until the bubbles are completely eliminated, obtaining a complex crosslinking aid with a viscosity of 1500-2500 and a solid content of 45±3%; The complex crosslinking aid is added to the acrylic ester pressure-sensitive adhesive base solution prepared in S2.1 at a proportion of 5-8% of the total amount of the base solution, and stirred with a high-speed disperser for 15-25 minutes to obtain a uniformly mixed adhesive solution.

[0022] SS2, 8-12 parts of a polyaziridine compound is added dropwise and the shear rate threshold is maintained; In this embodiment, after the pre-mixing in SS1 is completed, the system temperature is maintained at 40-60°C and an inert atmosphere, 8-12 parts of a trifunctional aziridine compound (pentaerythritol tris(3-aziridinyl) propionate) is added dropwise through a micro-injection pump, the dropwise addition pipeline is heated and insulated (50±5°C) throughout to prevent aziridine crystallization and blockage at low temperature; A variable frequency speed-regulated anchor stirrer is used for stirring at the same time to ensure that the instantaneous local concentration gradient during dropwise addition is ≤0.5%; The viscosity change of the system is monitored in real time (online rotational viscometer, data acquisition frequency 1 Hz), and when the viscosity instantaneously increases by more than 15% of the initial value, a cooling program is automatically triggered (15°C cooling water is introduced into the jacket) to make the temperature fall back to the set range; The pH electrode is used to monitor the acidity and alkalinity of the system during the whole dropwise addition process (pH 6.5-7.5 is maintained), and if the pH < 6.5, the dropwise addition is automatically paused and 0.1 mol / L sodium hydroxide solution is injected for adjustment; After the drop, continue to maintain the current shear conditions for 10-15 minutes until the FTIR spectrum (online probe) shows that the aziridine characteristic peak intensity at 2250 cm -1 is stable (fluctuation <±3%), indicating uniform dispersion and no decomposition side reactions.

[0023] SS3, the final mixture is treated by ultrasonic defoaming.

[0024] In this embodiment, the mixture completed in step SS2 is immediately transferred to a stainless steel ultrasonic reactor, the variable frequency ultrasonic system is started, and the defoaming treatment is carried out under the condition that the temperature is maintained at 40-60°C and the nitrogen protection is continuously maintained (oxygen content <50 ppm); The ultrasonic probe is vertically fixed at a position with an immersion depth ≥10 cm and 1 / 3 height from the bottom of the reactor, and uses intermittent working mode. During this period, the liquid surface bubble escape condition is monitored in real time through the built-in high-definition camera, and the ultrasonic is terminated when the liquid surface bubble breakage rate is reduced to <5 / min. After treatment, the mixture is filtered through a 100 mesh metal screen, and the bubble residue is sampled and detected. Finally, a composite crosslinking aid with a viscosity of 1500-2500 , a bubble volume fraction of <0.01%, is obtained and immediately transferred to a sealed light-shielded container for storage.

[0025] S2.3, the mixed glue solution obtained in step S2.2 is uniformly coated on the back of the face material; Specifically, the mixed glue solution coating of step S2.3 uses slit extrusion coating, and the coating head is equipped with a temperature gradient control module to make the glue solution viscosity decrease along the coating direction.

[0026] In this embodiment, the mixed glue solution obtained in S2.2 is transferred to the feeding system of the slit extrusion coating machine, and is delivered to the coating die at a constant flow rate through the gear metering pump. The gap of the die slit is set to 1.5-2 times the target glue layer thickness. The coating head is equipped with three independent temperature control modules (partition length ratio 1:2:1), and the temperature is set from the inlet to the outlet: the first zone 35-40°C (to reduce the inlet viscosity of the glue solution to promote leveling), the second zone 25-30°C (to maintain stable shear thinning), and the third zone 20-25°C (to induce slight gelation on the surface). The gradient temperature difference is controlled within 15°C. The coating speed is controlled synchronously with the substrate speed to finally form a continuous glue layer without stripes and bubbles, and the temperature distribution fluctuation is ≤±1.5°C detected by the online infrared thermal imager.

[0027] As shown in Figure 3 S3, the glue layer on the back of the face material constructs a three-dimensional through-pore structure, which specifically includes: S3.1, during the coating process of the mixed glue solution, micron-sized inorganic powder is directionally dispersed on the surface of the mixed glue solution through a high-pressure gas jet device. Specifically, the high-pressure airflow jetting device in step S3.1 satisfies: The airflow contains a mixed medium of compressed air treated by molecular sieve dehumidification and atomized organic solvent vapor; An electrostatic field is applied immediately after the powder is scattered to orient the powder.

[0028] In this embodiment, while the mixed glue solution is being coated on the back of the face material, the high-pressure airflow jetting device is started to mix compressed air treated by molecular sieve dehumidification (dew point temperature lower than -40°C) and atomized organic solvent vapor (ketone or ester solvent with boiling point between 50-80°C) at a volume ratio to form an aerosol medium, and micron-sized inorganic powder (particle size not greater than one-third of the thickness of the glue layer) is jetted to the glue solution surface at supersonic speed airflow through a slit nozzle; The distance between the nozzle and the glue layer is kept constant, and the jetting angle is an acute angle relative to the running direction of the base material, ensuring that the powder is embedded in the glue solution surface layer to a depth not exceeding half of its total thickness; Immediately after the powder is scattered, the electrostatic generator is turned on to build a weak electrostatic field (field strength not exceeding one-fifth of the critical value of air breakdown) above the coating area, and the electric field direction is perpendicular to the base material plane, so that the charged powder is orderly arranged along the electric field line direction under the action of Coulomb force, forming a temporary fixed structure with single-particle dispersion; The powder addition amount and glue solution mass ratio are controlled at a low proportion during the whole process, and the powder coverage uniformity is monitored in real time by an infrared sensor to dynamically adjust the airflow pressure and electrostatic field strength to achieve single-layer dispersion of the powder, avoiding agglomeration or stacking.

[0029] S3.2, the face material coated with micron-sized inorganic powder is transferred to a closed environment with controllable temperature and humidity, so that the micron-sized inorganic powder and the mixed glue solution undergo interfacial penetration to form a continuous pore network with the powder as the skeleton; Specifically, the interfacial penetration process of step S3.2 is achieved by the following controls: An oxygen concentration suppression unit is provided in the closed environment; The base material running speed is dynamically coupled with the temperature and humidity change rate; An online microscopic imaging system is used to monitor the pore nucleation state.

[0030] In this embodiment, the face material after powder scattering is immediately transferred to a closed reaction cabin, which is equipped with an oxygen concentration suppression unit. By continuously introducing high-purity nitrogen into the cabin and assisted by vacuum suction, the internal oxygen concentration is maintained at a very low level (significantly lower than the atmospheric environment), effectively suppressing the oxidative crosslinking side reaction of organic components in the glue solution; The in-cabin temperature and humidity sensor is in real-time linkage with the external control system, and the temperature and humidity change curve is dynamically adjusted according to the running speed of the base material - when the base material runs at low speed, a slow-rising temperature and humidity profile is adopted to ensure sufficient penetration, and when it runs at high speed, a step profile is adopted to match the short residence time, so as to realize the accurate matching of mass transfer kinetics and reaction rate; Synchronously start the online microscopic imaging system, the long-focus lens of the system penetrates the cabin body observation window and focuses on the surface of the glue layer, the pore nucleation process starting from the micron-sized powder-glue interface is captured through continuous optical zoom, and the image data is analyzed in real time through a machine learning algorithm. Once the pore morphology deviates from the preset through network characteristics (such as isolated holes or collapsed structures), it is immediately fed back to the environmental control system to trigger the reconstruction and re-optimization of temperature and humidity parameters until the continuous pore network with inorganic powder as the skeleton and bridged to each other is stably formed.

[0031] S3.3, low-frequency vibration field is applied to the mixed glue liquid after the fusion of micron-sized inorganic powder, which promotes the uniform distribution of pores and eliminates interface bubbles, and a glue layer with three-dimensional through-pore structure is obtained; Specifically, the low-frequency vibration field of step S3.3 is applied in the initial solidification stage of the mixed glue liquid and is terminated before the critical gel point. The low-frequency vibration field is implemented to meet the following conditions: The vibration frequency decreases with the degree of glue layer solidification; An alternating magnetic field is superimposed in the vertical direction of the base material; The glue liquid is at the critical gel point when the vibration is terminated.

[0032] In this embodiment, after the interface penetration of S3.2 is completed, a low-frequency vibration field is immediately applied to the glue layer which has initially formed a pore network. The vibration field is started when the glue liquid enters the initial solidification stage but is far from macroscopic gelation; The vibration platform generates simple harmonic vibration perpendicular to the base material plane through an electromagnetic exciter, and the frequency is gradient-adjusted according to the online real-time monitoring of the complex viscosity of the glue liquid - a relatively high frequency is used in the initial stage to effectively destroy residual bubbles and promote powder migration, and as the degree of solidification deepens (manifested as viscosity rising), the vibration frequency is continuously and smoothly reduced to avoid excessive shear of the fragile pore skeleton that has been initially formed; At the same time, a low-frequency alternating magnetic field is superimposed in the vertical direction of the base material, which is generated by a Helmholtz coil, and the frequency has a specific proportional relationship with the mechanical vibration frequency, which aims to make the magnetic or polarizable inorganic powder components in the glue liquid produce micro-amplitude Lorentz force motion, thereby further optimizing the spatial distribution and connectivity of the pores; The entire vibration process continues until the online rheometer detects that the viscosity of the glue solution reaches the critical gel point (i.e., the intersection point of the storage modulus G' and the loss modulus G'') immediately before the vibration and magnetic field are terminated, at which time the glue solution has sufficient structural strength to maintain the ideal three-dimensional through-pore structure that has been formed, while avoiding the possibility of structural damage caused by vibration after complete gelation.

[0033] Specifically, the formation of the three-dimensional through-pore structure needs to meet the following conditions: The surface of the micron-sized inorganic powder is modified with active groups that react with the cross-linking aid; The pore network is gradiently distributed in the thickness direction of the glue layer; The maximum pore size of the pore network does not exceed 1 / 2 of the thickness of the glue layer.

[0034] In this embodiment, the formation of the three-dimensional through-pore structure needs to meet the following core conditions: First, the surface of the micron-sized inorganic powder used needs to be pre-treated with a silane coupling agent to modify it with active functional groups (such as amino or epoxy groups) that can chemically react with the active components (such as aziridine or oxazoline groups) in the cross-linking aid, ensuring that the powder can form a stable pore framework by forming a firm chemical bond with the glue solution rather than physical adsorption during the interface penetration stage S3.2; Second, by controlling the energy transmission mode and direction of the low-frequency vibration field in S3.3, the vibration wave forms an energy gradient decay in the thickness direction of the glue layer, which in turn drives the gradient distribution of the pore structure—lower porosity and smaller pore size on the side close to the face material to enhance anchoring force, and higher porosity and larger pore size on the side close to the surface of the glue layer to improve initial adhesion; Finally, by process parameter constraints (such as powder particle size selection, vibration frequency adjustment, and solidification rate control) during the entire pore-forming process, it is ensured that the maximum size of any single pore in the final formed pore network does not exceed one-half of the total thickness of the glue layer, and this proportion limit can effectively avoid the risk of glue layer structure instability or tearing caused by local stress concentration, thereby ensuring that the three-dimensional through-pore network has both high specific surface area and mechanical reliability.

[0035] Specifically, the surface of the micron-sized inorganic powder is pre-treated with a silane coupling agent.

[0036] In this embodiment, the specific way of pre-treating the surface of the micron-sized inorganic powder with a silane coupling agent is as follows: Micron-sized inorganic powder is preheated in a high-speed mixer to remove surface-adsorbed water, and then a pre-hydrolyzed silane coupling agent ethanol solution is uniformly sprayed in an atomized form into the powder under stirring, the silane coupling agent is selected from amino or epoxy functional groups, and the amount is 0.5% to 2.5% of the mass of the powder, the hydrolysis solution solvent is a mixture of ethanol and water, and the pH value is adjusted to weak acidity to promote the formation of silanol groups, after spraying, the hydrolyzed silane and the powder surface hydroxyl group are fully condensed to form a hydrophobic powder with active functional groups on the surface, and the pre-treatment ensures that the powder can form a firm chemical bonding interface with the reactive components in the cross-linking aid in the subsequent S3.2 step instead of physical adsorption, thereby significantly enhancing the stability of the pore network.

[0037] S4, the S3 treated face material is controlled by a coating device to control the thickness of the adhesive layer, an optical detection system is used to real-time feedback coating uniformity data, the adhesive coated face material is combined with the release layer of the base paper, and after integrated by an elastic pressure roller, it enters a segmented drying program; In this embodiment, the face material treated by S3 and having formed a three-dimensional through-pore structure is introduced into a high-precision slot extrusion coating device, the mixed glue liquid delivery amount is accurately adjusted by a closed-loop controlled gear metering pump, and the glue layer thickness is controlled in a preset range; At the same time, an optical detection system based on the principle of laser triangulation is used to scan the wet film, and the detection data is real-time feedback to the fine adjustment actuator of the coating die, and the lip opening and the base material tension are dynamically adjusted by an adaptive algorithm to ensure that the coating uniformity variation coefficient is less than 3%; Then, the adhesive coated face material and the release layer of the base paper are precisely aligned and combined under constant tension, the composite pressure is provided by a pair of pressure rollers coated with high-elastic polyurethane adhesive layer, and the pressure value is accurately calculated to ensure that the air between the layers can be effectively removed without crushing the three-dimensional pore structure formed; the composite material immediately enters a segmented drying program, the first stage uses medium-low temperature and large air volume convection drying to gently remove most of the solvent without causing surface film effect, and the second stage uses far infrared radiation drying with gradually increasing temperature to fully carry out cross-linking reaction and finally solidify and shape.

[0038] S5, a weather-resistant protective coating is applied to the surface of the dried adhesive paper, the coating contains nano-enhanced particles and high-molecular dispersion medium, and is cold-pressed and shaped by a multi-stage tension control device to eliminate interlayer stress; In this embodiment, a weather-resistant protective coating is applied to the surface of the dried and solidified adhesive paper by a precise micro-gravure coating process, the coating is prepared by dispersing nano-enhanced particles, surface-modified nano-silicon dioxide, and high-molecular dispersion medium, fluoropolymer, in a co-solvent system in a specific ratio, and its function is to significantly improve the product's anti-ultraviolet aging, moisture resistance, and anti-pollution performance. Immediately after coating, it enters the cold pressure setting unit equipped with multi-stage tension partition control device. Through the closed-loop linkage of multiple driving rollers and tension sensors, the device realizes the accurate and progressive adjustment of the tension of the material in the length direction, so as to eliminate the interlayer internal stress accumulated in the previous drying and coating process through pure mechanical extension and stress release without relying on heat, and finally obtain the adhesive paper product with stable size, high flatness and excellent durability.

[0039] S6, the adhesive paper after setting is tested for adhesion index, and is cut and wound after confirming that it meets the standard.

[0040] In this embodiment, after completing the cold pressure setting, the adhesive paper product is tested for adhesion index. First, the initial adhesion is measured by the inclined ball rolling method specified in GB / T 4852. A series of standard steel balls (usually from large to small) are rolled on the test plate at a certain inclination angle to reliably stick the largest ball size as the initial adhesion value. Then, the holding adhesion test is carried out according to GB / T 4851. The test sample of a certain size is pasted on the standard test plate, a weight of a certain weight is hung below it, and the time required for complete detachment is recorded in a constant temperature and humidity environment. Finally, the 180° peeling strength test is carried out according to GB / T 2792. The test sample and the standard test plate are separated at a certain speed, and the average peeling force is recorded. All test data are real-time recorded into the production management system (MES), and automatically compared with the preset internal quality control standard. Only when all adhesion indexes (initial adhesion, holding adhesion time, peeling strength) meet the standard, the product is allowed to enter the final cutting and winding section. The cutting process adopts a high-speed double-shaft center surface winding machine. According to the customer's required specifications, the precise cutting knife is used for slitting, and the multi-segment taper tension control algorithm is used to ensure the uniform tightness and neat end face of the roll during winding, so as to obtain the high-quality adhesive paper roll product meeting the customer's specification requirements.

[0041] Those skilled in the art can clearly make various modifications to the above embodiments without departing from the overall spirit and concept of the present application. All fall within the scope of the present application. The protection scheme of the present application is subject to the claims attached to the present application.

Claims

1. A process for producing a high tack adhesive paper, characterized by, The method comprises the following steps: S1, providing a face material and a base paper, performing corona treatment on the face material to improve surface activity, forming a release layer on the surface of the base paper, and coating an antistatic functional layer on the back of the face material; S2, coating a mixed glue solution on the surface of the face material, specifically comprising: S2.1, preparing an acrylate pressure-sensitive adhesive base solution, comprising a combination of acrylate main glue, multifunctional crosslinking agent and catalyst; S2.2, adding a composite crosslinking aid to the acrylate pressure-sensitive adhesive base solution obtained in step S2.1 to obtain a mixed glue solution, wherein the composite crosslinking aid is compounded by a water-soluble polymer containing reactive functional groups, a polyaziridine compound and a silicone modifier; S2.3, uniformly coating the mixed glue solution obtained in step S2.2 on the back of the face material; S3, constructing a glue layer with a three-dimensional through-pore structure on the back of the face material, specifically comprising: S3.1, during the coating process of the mixed glue solution, directing the micron-sized inorganic powder to be scattered on the surface of the mixed glue solution by a high-pressure airflow jetting device; S3.2, transferring the face material coated with micron-sized inorganic powder to a closed environment with controllable temperature and humidity, so that the micron-sized inorganic powder and the mixed glue solution are interfacially penetrated to form a continuous pore network with the powder as the skeleton; S3.3, applying a low-frequency vibration field to the mixed glue solution after the micron-sized inorganic powder is fused, so as to promote uniform distribution of the pores and eliminate interface bubbles, and obtain a glue layer with a three-dimensional through-pore structure; S4, controlling the glue layer thickness of the face material treated in S3 by a coating equipment, using an optical detection system to feed back the coating uniformity data in real time, and compounding the face material coated with glue and the release layer of the base paper, and then entering a segmented drying program after integrated by an elastic pressure roller; S5, applying a weather-resistant protective coating on the surface of the dried adhesive paper, wherein the coating comprises nano-enhanced particles and a high-molecular dispersion medium, and is cold-pressed and shaped by a multi-stage tension control device to eliminate interlayer stress; S6, testing the adhesive index of the shaped adhesive paper, and cutting and winding after confirming that it meets the standard.

2. The process for producing a high-tack adhesive paper according to claim 1, wherein The acrylate main glue in step S2.1 is composed of 50-70 parts of isooctyl acrylate, 15-25 parts of butyl acrylate and 1-3 parts of glycidyl methacrylate; The multifunctional crosslinking agent is a mixture of trimethylolpropane triacrylate and hexanediol diacrylate, and the mass ratio of the two is (1:0.5)-(1:1.2).

3. The process for producing a high-tack adhesive paper according to claim 1, wherein The compounding process of the composite crosslinking aid in step S2.2 comprises: SS1, first, mix 10-15 parts of the water-soluble polymer containing reactive functional groups with 5-8 parts of the silicone modifier under inert atmosphere, add a cosolvent during mixing and control the temperature at 40-60℃; SS2, then, add 8-12 parts of the polyaziridine compound drop by drop and maintain a shear rate threshold; SS3, finally, treat the mixture with ultrasonic defoaming.

4. The process for producing a high-tack adhesive paper according to claim 1, wherein The coating of the mixed glue solution in step S2.3 adopts slot extrusion coating, and the coating head is equipped with a temperature gradient control module to make the glue solution viscosity decrease along the coating direction.

5. The process for producing a high-tack adhesive paper according to claim 1, wherein The high-pressure airflow jetting device in step S3.1 meets the following requirements: The airflow comprises a mixture of compressed air treated by dehumidification and atomized organic solvent vapor; An electrostatic field is applied immediately after the powder is scattered to make the powder arrange directionally.

6. The process for producing a high-tack adhesive paper according to claim 5, wherein The interface penetration process of step S3.2 is achieved by controlling: Setting an oxygen concentration inhibition unit in a closed environment; Dynamically coupling the substrate running speed with the temperature and humidity change rate; Using an online microscopic imaging system to monitor the pore nucleation state.

7. The process for producing a high-tack adhesive paper according to claim 1, wherein The low-frequency vibration field of step S3.3 is applied in the initial curing stage of the mixed glue solution and is terminated before the critical gel point, and the low-frequency vibration field satisfies the following conditions when it is implemented: The vibration frequency decreases gradually with the degree of glue layer curing; An alternating magnetic field is superimposed in the vertical direction of the material; When the vibration is terminated, the glue solution is at the critical gel point.

8. The process for producing a high-tack adhesive paper according to claim 7, wherein The formation of the three-dimensional through-pore structure needs to meet the following conditions: The surface of the micrometer-sized inorganic powder is modified with active groups that react with cross-linking aids; The pore network is gradiently distributed in the thickness direction of the glue layer; The maximum pore size of the pore network does not exceed 1 / 2 of the thickness of the glue layer.

9. The process for producing a high-tack adhesive paper according to claim 8, wherein The surface of the micrometer-sized inorganic powder is pretreated with a silane coupling agent.

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