Acoustic enhancement material block, preparation method and electronic device

Abstract

The present disclosure relates to the technical field of acoustic materials, and in particular, provides an acoustic enhancement material block, a preparation method, and an electronic device. The preparation method of the acoustic enhancement material block comprises: mixing a porous sound-absorbing material, a resin adhesive, a structural reinforcing agent, an inorganic adhesive, a pore-forming agent, and water to obtain a uniformly dispersed acoustic enhancement slurry, placing the acoustic enhancement slurry into a mold for drying and hot pressing to obtain an acoustic enhancement material core block precursor, sintering the acoustic enhancement material core block precursor to obtain an acoustic enhancement material core block, and coating the acoustic enhancement material core block with a mesh material to obtain an acoustic enhancement material block. The acoustic enhancement material block, the preparation method, and the electronic device provided in the embodiments of the present disclosure are used to improve the pore uniformity of the acoustic enhancement material block and enhance the acoustic performance.

Description

Technical Field

[0001] The present disclosure relates to the technical field of acoustic materials, and in particular to an acoustic enhancement material block, a preparation method thereof, and an electronic device. Background Art

[0002] In consumer electronic micro speakers represented by mobile phones, laptops, augmented reality (AR), virtual reality (VR) and other devices, due to space limitations, the resonance cavity of the speaker is getting smaller and smaller, resulting in higher resonance frequency and lower low-frequency sound pressure sensitivity, making it difficult to improve its performance in the low-frequency range. Currently, the low-frequency performance of micro speakers is mainly improved by filling the speaker cavity with sound-absorbing materials.

[0003] However, when the sound absorbing material block is prepared in the related art, the pore uniformity of the sound absorbing material block is poor, which reduces the acoustic performance. Summary of the invention

[0004] The present disclosure is proposed in view of the above problems. The present disclosure provides an acoustic enhancement material block, a preparation method thereof, and an electronic device, which can improve the pore uniformity of the acoustic enhancement material block and enhance the acoustic performance.

[0005] According to a first aspect of the present disclosure, there is provided a method for preparing an acoustic enhancement material block, comprising:

[0006] Mixing a porous sound-absorbing material, a resin adhesive, a structural reinforcing agent, an inorganic binder, a pore-forming agent and water to obtain a uniformly dispersed acoustic enhancement slurry;

[0007] Placing the acoustic enhancement slurry into a mold for drying and hot pressing to obtain an acoustic enhancement material core block precursor;

[0008] Sintering the acoustic enhancement material core block precursor to obtain an acoustic enhancement material core block;

[0009] The acoustic enhancement material core block is coated with a mesh material to obtain an acoustic enhancement material block.

[0010] According to a second aspect of the present disclosure, there is provided an acoustic enhancement material block, comprising: the acoustic enhancement material core block as described in the first aspect and a mesh sealing layer coated on the outer surface of the acoustic enhancement material core block.

[0011] According to a third aspect of the present disclosure, an electronic device is provided, comprising the acoustic enhancement material block according to the second aspect of the present disclosure.

[0012] In one or more technical solutions provided in the embodiments of the present disclosure, a porous material, a resin adhesive, a structural reinforcement agent, an inorganic binder, a pore-forming agent and water are mixed to obtain a uniformly dispersed acoustic enhancement slurry, and then the acoustic enhancement slurry is placed in a mold for drying and hot pressing to obtain an acoustic enhancement material core block precursor, and the acoustic enhancement material core block precursor is sintered to obtain an acoustic enhancement material core block. Since the porous sound-absorbing material is a porous structure, its own strength is relatively limited and it is easy to be damaged when subjected to external forces. The structural reinforcement can interact with other components after sintering. For example, it can cooperate with the inorganic binder to fill the pores of the porous sound-absorbing material and the gaps between the components, playing a supporting role similar to a "skeleton", thereby improving the strength and compressive resistance of the acoustic enhancement material block, and effectively reducing the risk of porous substances falling off and contaminating the speaker during vibration. At the same time, adding pore formers to the slurry can help improve the porosity and specific surface area of ​​the porous sound-absorbing material. When the acoustic enhancement material core block precursor is sintered, the pore former will decompose and produce gases such as carbon dioxide. These gases are released from other materials, thereby forming more pores and improving the acoustic performance.

[0013] On this basis, an acoustic enhancement material block is obtained by first sintering to prepare an acoustic enhancement material core block and then sealing the acoustic enhancement material core block with a mesh material. When the acoustic enhancement material core block is first sintered, the core block undergoes a high-temperature sintering process under relatively stable conditions without external constraints, and its internal porous structure and the combination of various components can be formed in an ideal state, thereby improving the pore uniformity of the acoustic enhancement material block and enhancing the acoustic performance. Moreover, if the acoustic enhancement material core block produces powder loss after long-term use, the mesh material can also provide a protective layer for the acoustic enhancement material core block, reducing the possibility of falling powder entering other areas of the electronic device, and protecting other areas of the electronic device from damage as much as possible.

[0014] In addition, when preparing the acoustic enhancement slurry, no fiber material is used, which can prevent the residual carbon produced after the subsequent sintering of the fiber material from adhering to other materials, changing the physical and chemical properties of the material surface, and affecting the reflection and absorption process of sound waves. Moreover, it can prevent the residual carbon from falling off and blocking the pores of the porous material, reducing the channels for sound waves to enter the pores, and causing the problem of reduced acoustic performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and other purposes, features and advantages of the present disclosure will become more apparent by describing the embodiments of the present disclosure in more detail in conjunction with the accompanying drawings. The accompanying drawings are used to provide a further understanding of the embodiments of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure and do not constitute a limitation of the present disclosure. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0016] Figure 1 A flowchart of the preparation of the acoustic enhancement material block according to an embodiment of the present disclosure;

[0017] Figure 2 A diagram of a sealing state of the acoustic enhancement material block according to an embodiment of the present disclosure;

[0018] Figure 3 A schematic diagram of the cross-sectional structure of an acoustic enhancement material block provided in an embodiment of the present disclosure.

[0019] 310 - core block of acoustic enhancement material, 320 - mesh material layer, 330 - edge retention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present disclosure more obvious, the exemplary embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure, and it should be understood that the present disclosure is not limited to the exemplary embodiments described here.

[0021] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present disclosure, "multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0023] In the description of the present disclosure, it is necessary to understand that the directions or positional relationships indicated by the terms "upper", "lower", "front", "back", "left", "right", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present disclosure.

[0024] In the description of the present disclosure, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0025] It should be noted that, in the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the present disclosure should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

[0026] In the present invention, "at least one" means one or more, and "plurality" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, the combination of a and b, the combination of a and c, the combination of b and c, or the combination of a, b and c, where a, b, c can be single or multiple.

[0027] In traditional audio, porous sound-absorbing materials such as activated carbon, sound-absorbing cotton or fiber products are widely used to improve sound absorption performance. However, in consumer electronic micro speakers represented by mobile phones, laptops, AR and VR devices, the contradiction between acoustic performance and space in the low-frequency part has long existed due to volume limitations. Through practice, scientists have creatively proposed the "Virtual Back Volume" (VBV) technology, which successfully solved the problem of sound-absorbing products in smartphones, namely: using granular porous materials of special materials or different packaging forms of these materials, when the speaker diaphragm vibrates at high frequency, the high-frequency adsorption and desorption of air are achieved through a fine three-dimensional pore structure, thereby reducing the resistance of the diaphragm, forming an acoustic effect similar to increasing the actual physical back cavity, reducing the resonant frequency, and greatly increasing the acoustic performance, especially the low-frequency performance.

[0028] There is technology that usually fills the sound-absorbing particles into the speaker cavity by canning, but the canning process is relatively difficult. In particular, the resonance cavity space of some miniature speakers is very small, and its spatial height is in the range of hundreds of microns. It is very difficult to quantitatively fill sound-absorbing particles in such a narrow resonance cavity. However, the narrow resonance cavity often has the greatest impact on low frequencies, and it is also the structure that most needs to be filled with sound-absorbing materials. Secondly, during the operation of the speaker, traditional sound-absorbing particles vibrate at high frequencies in the cavity and collide with the inner wall of the cavity, causing the sound-absorbing particles to break and break into powder, damaging the speaker unit. In addition, in the current filling process, sound-absorbing particles can only fill about 80% of the volume of the back cavity of the speaker module, and cannot fully utilize the back cavity space.

[0029] When preparing the coated sound-absorbing material block in the related art, since the sintering process is a post-sintering process, during sintering, due to the presence of the coating layer and its own thermal expansion and contraction characteristics and other factors, uneven external force will be exerted on the acoustic enhancement material filled inside, causing the originally uniform pore structure inside the core block to be destroyed, resulting in local pore deformation, blockage or loose bonding of the components, affecting the acoustic performance and mechanical properties of the material.

[0030] Therefore, the related art solves this technical problem by preparing a sound-absorbing block. For example, the sound-absorbing material particles are bonded together with bonding fibers, a binder or other components to obtain a sound-absorbing block, which is then cut into the required size and filled into the cavity of the speaker. However, when the material block is cut, the particles of the sound-absorbing material are easily chopped into small powders, and there is still the problem of powdering and falling off of the sound-absorbing material, which affects the acoustic performance.

[0031] In view of the above problems, the embodiments of the present disclosure provide an acoustic enhancement material block, a preparation method and an electronic device, which can prepare the acoustic enhancement material block into a required size without cutting the acoustic enhancement material block, thus avoiding the possibility of powder falling during cutting and ensuring the stability of the acoustic material during use. The electronic device may include at least one of a smart phone, a tablet computer, a laptop computer and a smart watch.

[0032] The embodiment of the present disclosure provides a method for preparing an acoustic enhancement material block, which can be used to prepare the acoustic enhancement material block of the embodiment of the present disclosure. Figure 1 The preparation flow chart of the acoustic enhancement material block according to the embodiment of the present disclosure is shown as follows: Figure 1 As shown, the method for preparing the acoustic enhancement material block of the embodiment of the present disclosure includes:

[0033] Step 101: Mix the porous sound-absorbing material, the resin adhesive, the structural reinforcing agent, the inorganic binder, the pore-forming agent and water to obtain a uniformly dispersed acoustic enhancement slurry. It should be understood that the acoustic enhancement slurry is a paste slurry.

[0034] In the embodiment of the present disclosure, since the porous sound-absorbing material is a porous structure, its own strength is relatively limited and it is easy to be damaged when subjected to external forces. The structural reinforcement agent can interact with other components after sintering, for example, it can cooperate with the inorganic binder to fill the pores of the porous sound-absorbing material and the gaps between the components, playing a supporting role similar to a "skeleton", improving the strength and compressive performance of the acoustic enhancement material block, and effectively reducing the risk of porous materials falling off and contaminating the speaker during vibration. At the same time, adding a pore-forming agent to the slurry helps to improve the porosity and specific surface area of ​​the porous sound-absorbing material. When the precursor of the acoustic enhancement material core block is sintered, the pore-forming agent will decompose and produce gases such as carbon dioxide, which are released from other materials, thereby forming more pores and improving the acoustic performance.

[0035] On this basis, resin adhesives can better bond the various components together, and inorganic adhesives can enhance the bonding effect under some special conditions (such as high temperature environment, etc.). The combination of the two makes the various components inside the material tightly combined, ensuring that the material can still maintain the integrity of the overall structure under long-term use, external impact or vibration, etc., and is not prone to cracking, breakage or component shedding, thereby extending the service life of the material.

[0036] Exemplarily, in the preparation method of the acoustic enhancement material block of the embodiment of the present disclosure, the porous material, the resin binder, the structural reinforcement agent, the inorganic binder, the pore former and water are mixed to obtain a uniformly dispersed acoustic enhancement slurry, specifically comprising: first, the porous sound-absorbing material, the structural reinforcement agent, the inorganic binder and the pore former are mixed to obtain a mixed dry material. Then, the mixed dry material is dispersed in the resin binder and water for blending to obtain an acoustic enhancement slurry. For example: the porous sound-absorbing material, the structural reinforcement agent, the inorganic binder and the pore former are mixed, and then mixed with the resin binder and water to form a uniformly dispersed acoustic enhancement slurry.

[0037] The porous sound-absorbing material, structural reinforcement agent, inorganic binder and pore-forming agent are first mixed to obtain a dry blend, and then the dry blend is dispersed into a resin binder and water. Since the resin binder and water are liquids, the dry blend can be evenly dispersed, thereby making the components in the acoustic enhancement slurry more evenly mixed.

[0038] The porous sound-absorbing material may include at least one of a porous molecular sieve, a porous silica aerogel and activated carbon. The activated carbon may be high-porosity activated carbon. The average particle size of the porous sound-absorbing material is 200 nm to 250 nm, and the porous molecular sieve includes an MFI zeolite molecular sieve or a Bea type molecular sieve.

[0039] The resin binder may include a water-dispersible polymer, for example, at least one of waterborne polyurethane, waterborne polyurethane acrylate, epoxy-modified resin and silicone resin.

[0040] The structural reinforcing agent may include at least one of porous quartz powder, white carbon black, glass powder particles, clay, talc and porous calcium carbonate.

[0041] For the above-mentioned inorganic binder, it can include at least one of silica sol, phosphate and silicate. Among them, the phosphate inorganic binder can include tripolyphosphate adhesive or polyacrylic acid phosphate adhesive. The silicate inorganic binder can include calcium carbonate or glass powder.

[0042] The pore former may include at least one of polymethyl methacrylate, polyvinyl alcohol, polyacrylic acid, polyimide, polyethylene and polypropylene.

[0043] In one achievable manner, in the acoustic enhancement slurry of the embodiment of the present disclosure, the mass ratio of water to the total mass of other components is (40-70):(30-60).

[0044] The mesh material may be a thin felt with a certain air permeability and porosity, and the material of the mesh material may include at least one of polyester, polypropylene and nylon.

[0045] Step 102: placing the acoustic enhancement slurry into a mold for drying and hot pressing to obtain an acoustic enhancement material core block precursor.

[0046] For example, the acoustic enhancement slurry may be first filled into a mold provided with grooves of a certain depth, and then dried and hot-pressed to obtain an acoustic enhancement material core block precursor.

[0047] In practical applications, the embodiment of the present disclosure fills the acoustic enhancement slurry into a mold with a groove of a certain depth, and then forms the acoustic enhancement slurry into an acoustic enhancement material core block precursor by drying it first and then hot pressing it. During the drying process, the moisture or some volatile solvent components in the slurry can be removed first, reducing the bubbles and uneven pores that may be generated in the subsequent hot pressing process due to the presence of volatile components such as moisture, which helps to make the internal structure of the material more dense and uniform, and prepare for the hot pressing process. Hot pressing can further compact and shape the dried material, and the high temperature of hot pressing helps to cause some physical and chemical changes between the internal components of the material, such as promoting the resin adhesive and inorganic adhesive to better play a bonding role, improving the performance of the material, and finally obtaining the acoustic enhancement material core block precursor.

[0048] In one example, the drying temperature is 90°C to 150°C, and the drying time is 0.5h to 5h. The hot pressing conditions include: the hot pressing pressure is 1.5Mpa to 5Mpa, the hot pressing temperature is 160°C to 250°C, and the hot pressing time is 5min to 15min.

[0049] Exemplarily, before placing the acoustic enhancement slurry into the mold, the mold can be demolded first, and the demolding method can include spraying a demolding agent, laying a high temperature resistant release paper or release film. The depth and size of the mold groove can be selected according to the assembly requirements of the acoustic enhancement material. Therefore, after the subsequent molding and curing are completed, the acoustic enhancement material block can be removed from the mold more smoothly. If the inner surface of the mold is relatively sticky and has not undergone appropriate demolding treatment, it may cause the product to adhere to the mold, and even breakage and deformation may occur during the demolding process, affecting the quality and appearance of the final product. Moreover, the inner surface of the mold after demolding is smoother and cleaner, which helps to make the surface of the acoustic enhancement slurry precursor after molding flat and smooth, and reduce surface defects caused by problems such as mold adhesion.

[0050] For example, the release agent may include at least one of talc, mica powder, clay, white clay, fatty acid, vaseline, silicone oil, polyethylene glycol, and low molecular weight polyethylene. The release paper or release film has a thickness of 0.03 mm to 0.05 mm and a temperature resistance of more than 220°C.

[0051] For example, in the acoustic enhancement material core block precursor, the mass ratio of the porous sound absorbing material, the resin adhesive, the structural reinforcing agent, the inorganic binder, and the pore forming agent is (46-76): (15-28): (1-10): (5-9): (3-7). By rationally configuring the mass ratio of each component, the best sound absorption effect of the material can be achieved, the structural and performance stability can be ensured, and the requirements of different application scenarios can be met.

[0052] Step 103: Sintering the acoustic enhancement material core block precursor to obtain an acoustic enhancement material core block.

[0053] Exemplarily, the acoustic enhancement material core block precursor can be sintered at a sintering temperature of 450°C to 600°C and a sintering time of 2min to 30min to obtain an acoustic enhancement material core block. By processing within the sintering temperature and time range, the particles inside the material will be more tightly bound. The relatively loose structure in the acoustic enhancement material core block precursor stage will diffuse and fuse with each other after sintering to form a more stable connection, making the overall structure of the acoustic enhancement material core block more compact, which can effectively resist external mechanical stress, extend the service life of the material, and ensure its long-term and stable acoustic function. The sintering process further optimizes the internal pore structure of the material. Some pores that were originally irregular, poorly connected or unreasonable in size are adjusted under the action of sintering, making the pore distribution more uniform and reasonable.

[0054] On this basis, during the sintering process, the porogen will decompose and produce gases such as carbon dioxide. The gases can fully diffuse inside the material and expand the corresponding space, forming a large number of pores inside the material, so that the core block of the acoustic enhancement material has a rich pore structure, which significantly improves the porosity of the acoustic enhancement material block, greatly increasing the space available for sound propagation, scattering, and friction inside the material. After the sound enters the material, it has more opportunities to interact with the pore wall, thereby more effectively converting sound energy into other forms of energy such as heat energy, thereby enhancing the sound absorption effect. At the same time, higher porosity also increases the specific surface area of ​​the material. The increase in specific surface area makes the interface between the material and the sound more extensive, further improving the efficiency of sound absorption, especially for sounds of different frequencies. It can have better capture and consumption capabilities, broadening the coverage of the material in the sound absorption band.

[0055] Step 104: The acoustic enhancement material core block is coated with a mesh material to obtain an acoustic enhancement material block.

[0056] For example, the acoustic enhancement material core block can be sealed using a heat-sealed tea bag packaging method. In the sealed acoustic enhancement material block, the mesh material has a margin of 5 μm to 20 μm, so that when assembling it in certain speakers, the acoustic enhancement material block can be adhered to the speaker assembly, thereby fixing the acoustic enhancement material block, reducing the chance of powder falling off due to vibration of the acoustic enhancement material block, and ensuring the stability of the acoustic enhancement material block during use.

[0057] In one example, Figure 2 FIG. 2 shows a sealing state diagram of an acoustic enhancement material block according to an embodiment of the present disclosure. Figure 2 As shown, if there are multiple acoustic enhancement material core blocks, the multiple acoustic enhancement material core blocks can be arranged and sealed at the same time, and adjacent sealed block-shaped sound-absorbing materials can be cut with 5μm to 20μm edge seals reserved.

[0058] The disclosed embodiment prepares an acoustic enhancement material core block by first sintering and then uses a mesh material to seal the acoustic enhancement material core block to obtain an acoustic enhancement material block. When the acoustic enhancement material core block is first sintered, the core block undergoes a high-temperature sintering process under relatively stable conditions without external constraints, and its internal porous structure and the combination of various components can be formed in an ideal state, thereby improving the pore uniformity of the acoustic enhancement material block and enhancing the acoustic performance. Moreover, if the acoustic enhancement material core block produces powder loss after long-term use, the mesh material can also provide a protective layer for the acoustic enhancement material core block, reducing the possibility of falling powder entering other areas of the electronic device, and protecting other areas of the electronic device from damage as much as possible.

[0059] In addition, when preparing the acoustic enhancement slurry, no fiber material is used, which can prevent the residual carbon produced after the subsequent sintering of the fiber material from adhering to other materials, changing the physical and chemical properties of the material surface, and affecting the reflection and absorption process of sound waves. Moreover, it can prevent the residual carbon from falling off and blocking the pores of the porous material, reducing the channels for sound waves to enter the pores, and causing the problem of reduced acoustic performance.

[0060] In one achievable manner, the thermal decomposition temperature of the resin binder of the embodiment of the present disclosure is lower than the melting temperature of the inorganic binder, and the thermal decomposition temperature of the pore former is lower than the melting temperature of the inorganic binder.

[0061] In actual applications, at the beginning of the hot pressing process or just after sintering, when the temperature has not reached the thermal decomposition temperature of the resin adhesive, the resin adhesive can effectively bond the porous sound-absorbing material, structural reinforcement and other components together, so that the material has a preliminary shape and a certain structural stability, which is convenient for subsequent processing. However, as the preparation process enters the high-temperature sintering stage, the temperature rises and causes the resin adhesive to thermally decompose, and the bonding system originally constructed by it faces the risk of failure. But at this time, the inorganic adhesive begins to melt, and with its own characteristics, it intervenes and fills the bonding gap left after the failure of the resin adhesive, and re-bonds the porous sound-absorbing material, structural reinforcement, etc., to form a new and more stable bonding structure, ensuring that the material can still maintain its overall integrity and strength after undergoing the critical process of high-temperature sintering.

[0062] On this basis, the thermal decomposition temperature of the pore former is lower than the melting temperature of the inorganic binder, so that during the material preparation process, the pore former can change before the inorganic binder. When the temperature rises to the thermal decomposition temperature of the pore former, the pore former begins to decompose and produce gas, thereby forming pores inside the material. Since the inorganic binder has not yet melted at this time, it will not hinder the pore forming process. The gas can escape smoothly from the material to form a uniformly distributed pore structure, which is conducive to improving the porosity of the material. Since the melting of the inorganic binder occurs after the decomposition of the pore former, during the pore forming process, the material mainly relies on components such as resin adhesives to maintain a certain shape and structural stability. When the inorganic binder is melted, the material can be bonded and reinforced on the basis of the already formed pore structure. This not only ensures the effective formation of pores, but also prevents the material from becoming too loose due to the pore forming process, thereby maintaining the bonding integrity of the material. For example, during the sintering process, the inorganic binder can be filled around the pores after melting to enhance the overall strength of the material, so that the sound-absorbing material block has good sound absorption performance while also having sufficient mechanical strength to withstand external forces.

[0063] In an achievable manner, the air permeability of the mesh material of the embodiment of the present disclosure is ≥ 200 gsm, and the grammage of the mesh material is 5 g / m 2 ~10g / m 2 Air permeability ≥ 200gsm indicates that the mesh material has excellent air permeability, and air can pass through the mesh material relatively smoothly. In practical applications, the mesh material can enable the air driven by sound propagation to better interact with the pore structure inside the material. The air vibration caused by the sound can be smoothly transmitted to the internal sound-absorbing main part through the mesh material, and then the sound can be more effectively scattered and rubbed in the pores of the acoustic enhancement material block, thereby converting sound energy, which helps to improve the overall sound absorption effect to a certain extent.

[0064] The present disclosure also provides an acoustic enhancement material block. Figure 3 FIG. 2 shows a schematic cross-sectional structure diagram of an acoustic enhancement material block provided by an embodiment of the present disclosure. Figure 3 As shown, the acoustic enhancement material block of the embodiment of the present disclosure includes an acoustic enhancement material core block 310 and a mesh material layer 320 coated on the acoustic enhancement material core block 310, and the mesh material layer has a margin 330 of 5 microns to 20 microns. Therefore, if the acoustic enhancement material core block produces powder falling after long-term use, the mesh material can also provide a protective layer for the acoustic enhancement material core block, reducing the possibility of falling powder entering other areas of the electronic device, and protecting other areas of the electronic device from damage as much as possible.

[0065] The present disclosure also provides an electronic device, which includes a speaker cavity filled with an acoustic enhancement material block according to the present disclosure. The electronic device may include at least one of a smartphone, a tablet computer, a laptop computer, a smart watch, VR, and AR.

[0066] In order to verify the effect of the acoustic enhancement material block provided by the embodiment of the present disclosure, the embodiment of the present disclosure is demonstrated by comparing the embodiment with a comparative example.

[0067] Embodiment 1

[0068] The first embodiment of the present disclosure provides an acoustic enhancement material block, and the preparation method thereof comprises the following steps:

[0069] The ratio of the mass of water to the total mass of other components in the acoustic enhancement slurry is 70:30. Taking the total weight of the other components except water, i.e. the precursor of the acoustic enhancement material core block, as 100%, the porous sound absorbing material (porous MFI zeolite molecular sieve) accounts for 64%, the resin binder (waterborne polyurethane) accounts for 17%, the structural reinforcing agent (porous quartz powder) accounts for 6%, the inorganic binder (tripolyphosphate adhesive) accounts for 8%, and the pore-forming agent (polymethyl methacrylate) accounts for 5%.

[0070] The first step is to prepare an acoustic enhancement slurry: porous MFI zeolite molecular sieve with an average particle size of 200 nm, porous quartz powder, tripolyphosphate adhesive, and polymethyl methacrylate dry powder are evenly blended, and then mixed with water-based polyurethane and water to form a uniformly dispersed paste slurry, namely, the acoustic enhancement slurry.

[0071] The second step is to prepare the acoustic enhancement material core block precursor: first, the acoustic enhancement slurry of the first step is filled into a mold with a groove depth of 1 mm and dried at 90°C for 5 hours. Then, hot pressing is performed at a hot pressing temperature of 160°C, a hot pressing time of 15 minutes, and a pressure of 3 MPa to obtain the acoustic enhancement material core block precursor.

[0072] The third step is to prepare the acoustic enhancement material core block: the acoustic enhancement material core block precursor is sintered at a sintering temperature of 450° C. and a sintering time of 6 hours to obtain the acoustic enhancement material core block.

[0073] Step 4: Prepare acoustic enhancement material blocks: 2 The acoustic enhancement core block of the third step is sealed and cut with a polyester non-woven mesh material with an air permeability of 200 gsm to obtain an acoustic enhancement material block.

[0074] Embodiment 2

[0075] Embodiment 2 of the present disclosure provides an acoustic enhancement material block, and a preparation method thereof comprises the following steps:

[0076] The ratio of the mass of water to the total mass of other components in the acoustic enhancement slurry is 60:40. Taking the total weight of the other components except water, i.e. the precursor of the acoustic enhancement material core block, as 100%, the porous sound absorbing material (porous Bea type molecular sieve) accounts for 76%, the resin binder (waterborne polyurethane acrylate) accounts for 15%, the structural reinforcing agent (white carbon black) accounts for 4%, the inorganic binder (polyacrylic acid phosphate adhesive) accounts for 5%, and the pore-forming agent (polyvinyl alcohol) accounts for 3%.

[0077] The first step is to prepare an acoustic enhancement slurry: a porous Bea-type molecular sieve with an average particle size of 220 nm, white carbon black, polyacrylic acid phosphate adhesive, and polyvinyl alcohol dry powder are evenly blended, and then mixed with water-based polyurethane acrylate and water to form a uniformly dispersed paste slurry, namely, the acoustic enhancement slurry.

[0078] The second step is to prepare the acoustic enhancement material core block precursor: first, the acoustic enhancement slurry of the first step is filled into a mold with a groove depth of 1.2 mm and dried at 110°C for 3 hours. Then, hot pressing is performed at a hot pressing temperature of 200°C, a hot pressing time of 9 minutes, and a pressure of 2.5 MPa to obtain the acoustic enhancement material core block precursor.

[0079] The third step is to prepare the acoustic enhancement material core block: the acoustic enhancement material core block precursor is sintered at a sintering temperature of 500° C. and a sintering time of 4.5 h to obtain the acoustic enhancement material core block.

[0080] Step 4: Prepare acoustic enhancement material blocks: 2 The acoustic enhancement core block of the third step is sealed and cut with a polyester non-woven mesh material with an air permeability of 450gsm to obtain an acoustic enhancement material block.

[0081] Embodiment 3

[0082] Embodiment 3 of the present disclosure provides an acoustic enhancement material block, and a preparation method thereof comprises the following steps:

[0083] The ratio of the mass of water to the total mass of other components in the acoustic enhancement slurry is 50:50. Taking the total weight of the other components except water, i.e. the precursor of the acoustic enhancement material core block, as 100%, the porous sound absorbing material (porous silica aerogel) accounts for 63%, the resin binder (epoxy modified resin) accounts for 20%, the structural reinforcing agent (clay) accounts for 2%, the inorganic binder (calcium carbonate) accounts for 8%, and the pore forming agent (polyacrylic acid) accounts for 7%.

[0084] The first step is to prepare acoustic enhancement slurry: porous silica aerogel with a porosity of more than 98%, clay, calcium carbonate, and polyacrylic acid are evenly blended, and then mixed with epoxy modified resin and water to form a uniformly dispersed paste slurry, namely acoustic enhancement slurry.

[0085] The second step is to prepare the acoustic enhancement material core block precursor: first, the acoustic enhancement slurry of the first step is filled into a mold with a groove depth of 1.5 mm, and dried at 140°C for 1.5 hours. Then, hot pressing is performed at a hot pressing temperature of 230°C, a hot pressing time of 7 minutes, and a pressure of 1.8 MPa to obtain the acoustic enhancement material core block precursor.

[0086] The third step is to prepare the acoustic enhancement material core block: the acoustic enhancement material core block precursor is sintered at a sintering temperature of 550° C. and a sintering time of 4 hours to obtain the acoustic enhancement material core block.

[0087] Step 4: Prepare acoustic enhancement material blocks: 2 The acoustic enhancement core block of the third step is sealed and cut with a polyester non-woven mesh material with an air permeability of 550 gsm to obtain an acoustic enhancement material block.

[0088] Embodiment 4

[0089] Embodiment 4 of the present disclosure provides an acoustic enhancement material block, and a preparation method thereof comprises the following steps:

[0090] The ratio of the mass of water to the total mass of other components in the acoustic enhancement slurry is 40:60. Taking the total weight of the other components except water, i.e. the acoustic enhancement material core block precursor, as 100%, the porous sound absorbing material (activated carbon) accounts for 46%, the resin binder (silicone resin) accounts for 28%, the structural reinforcing agent (porous calcium carbonate) accounts for 10%, the inorganic binder (glass powder) accounts for 9%, and the pore forming agent (polyethylene) accounts for 7%.

[0091] The first step is to prepare acoustic enhancement slurry: activated carbon with a porosity of more than 95%, porous calcium carbonate, glass powder, and polyethylene are evenly blended, and then mixed with silicone resin and water to form a uniformly dispersed paste slurry, namely, acoustic enhancement slurry.

[0092] The second step is to prepare the acoustic enhancement material core block precursor: first, the acoustic enhancement slurry of the first step is filled into a mold with a groove depth of 1.6 mm, and dried at 150°C for 0.5 h. Then, hot pressing is performed at a hot pressing temperature of 250°C, a hot pressing time of 5 min, and a pressure of 1.5 MPa to obtain the acoustic enhancement material core block precursor.

[0093] The third step is to prepare the acoustic enhancement material core block: the acoustic enhancement material core block precursor is sintered at a sintering temperature of 600° C. and a sintering time of 3 h to obtain the acoustic enhancement material core block.

[0094] Step 4: Prepare acoustic enhancement material blocks: 2The acoustic enhancement core block of the third step is sealed and cut with a polyester non-woven mesh material with an air permeability of 700 gsm to obtain an acoustic enhancement material block.

[0095] Comparative Example 1

[0096] Comparative Example 1 of the present disclosure provides an acoustic enhancement material block, and the preparation method thereof comprises the following steps:

[0097] The ratio of the mass of water to the total mass of other components in the acoustic enhancement slurry is 40:60. Taking the total weight of the other components except water, i.e. the acoustic enhancement material core block precursor, as 100%, the porous sound absorbing material (porous MFI zeolite molecular sieve) accounts for 64%, the resin binder (waterborne polyurethane) accounts for 17%, the structural reinforcing agent (porous quartz powder) accounts for 6%, the inorganic binder (tripolyphosphate adhesive) accounts for 8%, and the pore-forming agent (polymethyl methacrylate) accounts for 5%.

[0098] The first step is to prepare the acoustic enhancement material: porous MFI zeolite molecular sieve with an average particle size of 200 nm, porous quartz powder, tripolyphosphate adhesive, polymethyl methacrylate and water-based polyurethane are blended to obtain the acoustic enhancement material.

[0099] The second step is to prepare the acoustic enhancement material block: first, the acoustic enhancement material of the first step is dried at 90°C for 5 hours, and then filled with a 5g / m 2 , a polyester non-woven mesh material with an air permeability of 200gsm. Then, it was dried at 90℃ for 5h, hot pressed at a temperature of 160℃, a time of 15min, and a pressure of 3MPa. Finally, it was sintered at a temperature of 450℃ and a time of 6h to obtain an acoustic enhancement material block.

[0100] Comparative Example 2

[0101] Comparative Example 2 of the present disclosure provides an acoustic enhancement material block, and the preparation method thereof comprises the following steps:

[0102] Taking the total weight of the acoustic reinforcement material core block as 100%, the porous sound-absorbing material (porous MFI zeolite molecular sieve) accounts for 69%, the resin adhesive (aqueous polyurethane) accounts for 17%, the structural reinforcement agent (porous quartz powder) accounts for 6%, and the inorganic binder (tripolyphosphate adhesive) accounts for 8%.

[0103] The first step is to prepare an acoustic enhancement slurry: porous MFI zeolite molecular sieve with an average particle size of 200 nm, porous quartz powder, and tripolyphosphate adhesive dry powder are evenly blended, and then mixed with water-based polyurethane and water to form a uniformly dispersed paste slurry, namely, the acoustic enhancement slurry.

[0104] The second step is to prepare the acoustic enhancement material core block precursor: first, the acoustic enhancement slurry of the first step is filled into a mold with a groove depth of 1 mm and dried at 90°C for 5 hours. Then, hot pressing is performed at a hot pressing temperature of 160°C, a hot pressing time of 15 minutes, and a pressure of 3 MPa to obtain the acoustic enhancement material core block precursor.

[0105] The third step is to prepare the acoustic enhancement material core block: the acoustic enhancement material core block precursor is sintered at a sintering temperature of 450° C. and a sintering time of 6 hours to obtain the acoustic enhancement material core block.

[0106] Step 4: Prepare acoustic enhancement material blocks: 2 The acoustic enhancement core block of the third step is sealed and cut with a polyester non-woven mesh material with an air permeability of 200 gsm to obtain an acoustic enhancement material block.

[0107] For the acoustic enhancement material blocks prepared in Examples 1 to 4 and Comparative Examples 1 to 2 of the present invention, the resonance frequency offset value Δf0 of the sheet acoustic enhancement material was tested respectively in accordance with Section 7.4 of the group standard "Porous Sound-Absorbing Particles for Micro Speakers" (Standard No.: T / CECA 78-2022).

[0108] The acoustic efficiency of the sheet acoustic enhancement material per unit mass is calculated according to the following formula:

[0109] Acoustic efficiency = Δf0 / (absolute dry mass of molecular sieve), unit: Hz / mg;

[0110] The results are shown in Table 1:

[0111] Table 1: Acoustic Enhanced Composite Material Performance Test Data

[0112] Sample name Sample acoustic efficiency 1m high 100 times drop test Acoustic efficiency durability Example 1 1.286 No shedding or powdering good Example 2 1.290 No shedding or powdering good Example 3 1.308 No shedding or powdering good Example 4 1.323 No shedding or powdering good Comparative Example 1 1.293 A small amount of powder good Comparative Example 2 1.265 No shedding or powdering deviation

[0113] It can be seen from the above table that the acoustic enhancement material blocks prepared by the embodiment of the present disclosure are compared with the acoustic enhancement material blocks prepared by comparative examples 1 to 3. Comparative example 1 adopts a post-sintering process, and comparative example 2 does not add the pore-forming agent of the embodiment of the present disclosure. Finally, the acoustic efficiency of the sample of the acoustic enhancement material block prepared by the embodiment of the present disclosure is higher, and there is no shedding or powdering in the 100-time drop test at a height of 1m, and the acoustic efficiency is more durable. It can be seen that the acoustic enhancement material block of the embodiment of the present disclosure adopts the method of first sintering the acoustic material and then coating it with a mesh material. When the acoustic enhancement material core block is first sintered to prepare the acoustic enhancement material core block, the core block undergoes a high-temperature sintering process under relatively stable conditions without external constraints. The porous structure inside it and the combination of the components can be formed in an ideal state, which improves the pore uniformity of the acoustic enhancement material block and improves the acoustic performance.

[0114] Additionally, as used herein, "or" used in a list of items beginning with "at least one" indicates a separate list, so that, for example, a list of "at least one of A, B, or C" means A or B or C, or AB or AC or BC, or ABC (i.e., A and B and C). Furthermore, the word "exemplary" does not mean that the example described is preferred or better than other examples.

[0115] It should also be noted that in the system and method of the present disclosure, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present disclosure.

[0116] Various changes, substitutions, and modifications of the techniques described herein may be made without departing from the teachings defined by the appended claims. Furthermore, the scope of the claims of the present disclosure is not limited to the specific aspects of the processes, machines, manufactures, compositions of events, means, methods, and actions described above. Currently existing or later to be developed processes, machines, manufactures, compositions of events, means, methods, or actions that perform substantially the same functions or achieve substantially the same results as the corresponding aspects described herein may be utilized. Thus, the appended claims include such processes, machines, manufactures, compositions of events, means, methods, or actions within their scope.

[0117] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present disclosure. Therefore, the present disclosure is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0118] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present disclosure to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A method for preparing an acoustic enhancement material block, characterized in that: include: Mixing a porous sound-absorbing material, a resin adhesive, a structural reinforcing agent, an inorganic binder, a pore-forming agent and water to obtain a uniformly dispersed acoustic enhancement slurry; Placing the acoustic enhancement slurry into a mold for drying and hot pressing to obtain an acoustic enhancement material core block precursor; Sintering the acoustic enhancement material core block precursor to obtain an acoustic enhancement material core block; The acoustic enhancement material core block is coated with a mesh material to obtain an acoustic enhancement material block.

2. The method for preparing an acoustic enhancement material block according to claim 1, characterized in that: The drying conditions include: the drying temperature is 90°C to 150°C, and the drying time is 0.5h to 5h; the hot pressing conditions include: the hot pressing pressure is 1.5Mpa to 5Mpa, the hot pressing temperature is 160°C to 250°C, and the hot pressing time is 5min to 15min; the sintering conditions include: the sintering temperature is 450°C to 600°C, and the sintering time is 2min to 30min.

3. The method for preparing an acoustic enhancement material block according to claim 1, characterized in that: The porous sound-absorbing material, the resin adhesive, the structural reinforcing agent, the inorganic binder, the pore-forming agent and water are mixed to obtain a uniformly dispersed acoustic enhancement slurry, comprising: Mixing a porous sound-absorbing material, a structural reinforcing agent, an inorganic binder and a pore-forming agent to obtain a mixed dry material; The blended dry materials are dispersed into a resin binder and water for blending to obtain an acoustic enhancement slurry.

4. The method for preparing an acoustic enhancement material block according to claim 1, characterized in that: The thermal decomposition temperature of the resin binder is lower than the melting temperature of the inorganic binder, and the thermal decomposition temperature of the pore former is lower than the melting temperature of the inorganic binder.

5. The method for preparing an acoustic enhancement material block according to claim 1, characterized in that: In the acoustic enhancement slurry, the ratio of the mass of water to the total mass of other components is (40-70): (30-60); In the acoustic enhancement material core block precursor, the mass ratio of the porous sound absorbing material, the resin adhesive, the structural reinforcing agent, the inorganic binder, and the pore-forming agent is (46-76):(15-28):(1-10):(5-9):(3-7).

6. The method for preparing an acoustic enhancement material block according to any one of claims 1 to 5, characterized in that: The porous sound-absorbing material comprises at least one of a porous molecular sieve, a porous silica aerogel and activated carbon; The resin adhesive includes at least one of waterborne polyurethane, waterborne polyurethane acrylate, epoxy modified resin and silicone resin; The structural reinforcing agent includes at least one of porous quartz powder, white carbon black, glass powder, clay, talcum powder and porous calcium carbonate; The inorganic binder includes at least one of silica sol, phosphate and silicate; The pore former includes at least one of polymethyl methacrylate, polyvinyl alcohol, polyacrylic acid, polyimide, polyethylene and polypropylene.

7. The method for preparing an acoustic enhancement material block according to any one of claims 1 to 5, characterized in that: The mesh material is made of at least one of polyester, polypropylene and nylon.

8. The method for preparing an acoustic enhancement material block according to any one of claims 1 to 5, characterized in that: The air permeability of the mesh material is ≥200gsm, and the grammage of the mesh material is 5g / m 2 ~10g / m 2 .

9. An acoustic enhancement material block, prepared according to the method for preparing an acoustic enhancement material block according to any one of claims 1 to 8, characterized in that: The acoustic enhancement material block comprises an acoustic enhancement material core block and a mesh material layer covering the outer surface of the acoustic enhancement material core block.

10. An electronic device, characterized in that: The electronic device comprises a speaker cavity, and the speaker cavity is filled with the acoustic enhancement material block according to claim 9.

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