Low-resistance moisture-proof respirator filter cotton, filter material for dustproof mask and dustproof mask

Abstract

The utility model relates to the technical field of air filter materials, in particular to low-resistance moisture-proof respirator filter cotton, a filter material for a dust mask and the dust mask. The filter cotton sequentially comprises three layers from outside to inside: an outer layer which is formed by acupuncture cotton or hot air cotton; the middle layer is made of tourmaline melt-blown non-woven fabric; the inner layer is formed by a net-shaped or framework-shaped non-woven fabric with high gram weight; the filter material for the dustproof mask is prepared by performing hot press molding on the low-resistance moisture-proof respirator filter cotton. The filter material for the dustproof mask is arranged on the body part of the dustproof mask. The gradient filtering structure improves the dust holding capacity, and is high in dust holding capacity and long in service life.

Description

TECHNICAL FIELD

[0001] The utility model relates to air filter material technical field especially a low resistance moistureproof respirator filter cotton, filter material for dust mask and dust mask. BACKGROUND

[0002] The self-suction filter type anti-particle respirator is the key protection equipment for guaranteeing the respiratory safety of the personnel working in the coal mine, and the core performance thereof is determined by the filter cotton inside. At present, the filter cotton technology commonly used in the industry mainly depends on the polypropylene (PP) melt-blown non-woven fabric. This kind of material carries static electricity on the surface of the fiber through the electrostatic standing pole process, so as to capture the fine coal dust particles by means of the electrostatic adsorption effect. Since the humidity in the coal mine environment is extremely large, the humidity in some deep wells or high water mines is even higher than 90% RH all the year round. The water molecules in the air are extremely easy to combine with the static electricity on the surface of the melt-blown fiber, which leads to the rapid neutralization and loss of the electricity. This makes the electrostatic adsorption capacity of the filter cotton greatly attenuate, and the filtration efficiency significantly decrease, especially for the respiratory dust with small particle size and great harm, the protection capacity will be deteriorated sharply, which directly threatens the life and health of the personnel working.

[0003] Therefore, the filter cotton in the prior art lacks the design for the coal mine environment, and there is the risk of poor user experience and safety hidden danger. CONTENT OF THE UTILITY MODEL

[0004] The utility model aims at solving the problems of the existing filter cotton that the static electricity dissipates fast in the high humidity environment of the mine, the filter cotton is easy to collapse and block the air flow channel after absorbing moisture, and the service life is short, adopts the technical means of combining the multi-layer gradient material composite with the concentric annular wave three-dimensional forming, and provides a low resistance moistureproof respirator filter cotton, filter material for dust mask and dust mask.

[0005] The utility model adopts the technical scheme that solves the technical problems:

[0006] A low resistance moistureproof respirator filter cotton, the filter cotton comprises three layers from outside to inside:

[0007] An outer layer, the outer layer is composed of needle-punched cotton or hot air cotton;

[0008] A middle layer, the middle layer is composed of tourmaline melt-blown non-woven fabric;

[0009] An inner layer, the inner layer is composed of high-grammage mesh or skeleton non-woven fabric.

[0010] In the low resistance moistureproof respirator filter cotton, the outer surface of the outer layer is provided with a flame-retardant finishing agent film;

[0011] In the low resistance moistureproof respirator filter cotton, the pore size range of the outer layer is 60-300 microns.

[0012] The outer surface of the tourmaline melt-blown non-woven fabric is provided with a hydrophobic and oleophobic finishing agent film.

[0013] The material of the hydrophobic and oleophobic finishing agent film is a fluorine-containing acrylic ester copolymer.

[0014] The pore size of the tourmaline melt-blown non-woven fabric is 1-20 microns.

[0015] The grammage of the high-grammage reticular or skeleton-shaped non-woven fabric is 50-80 g / m².

[0016] The material of the reticular or skeleton-shaped non-woven fabric is polyester fiber and / or polypropylene fiber.

[0017] The pore size of the reticular or skeleton-shaped non-woven fabric is 20-50 microns.

[0018] The material of the high-grammage reticular or skeleton-shaped non-woven fabric is selected from flame-retardant polyester fiber, flame-retardant polyamide fiber, aramid fiber, or a mixture of one or more of the above fibers and polypropylene fiber.

[0019] A filter material for a dust mask is made by hot-pressing the low-resistance moisture-proof respirator filter cotton into a shape, wherein the edges of the outer layer, the middle layer, and the inner layer are fixed together by ultrasonic welding or environmentally friendly hot melt glue, and the filter material for the dust mask is hot-pressed into a outwardly convex dome-shaped buffer.

[0020] The filter material for the dust mask is hot-pressed with several concentric ring-shaped corrugations, the cross section of the concentric ring-shaped corrugations is trapezoidal or sinusoidal, and the height difference between the peaks and valleys of the concentric ring-shaped corrugations is 2-8 mm.

[0021] The center of the concentric ring-shaped corrugations is the center of the filter material for the dust mask.

[0022] The filter material for the dust mask is provided with at least four hot-pressing support ribs distributed radially, and the three layers of material at the hot-pressing support ribs are fused into a hardened skeleton by high-density hot pressing.

[0023] A dust mask is provided with an air inlet valve on the body of the dust mask, and the filter material for the dust mask is provided on the body of the dust mask, the dome-shaped buffer is arranged opposite to the air inlet valve, and the distance between the dome-shaped buffer and the air inlet valve is at least 5 mm.

[0024] By employing the above technical solution, this utility model has at least the following advantages:

[0025] 1) The low-resistance moisture-proof respirator filter cotton provided by this utility model provides a high initial charge through the water electret in the middle layer, and the tourmaline dynamically replenishes the charge by the airflow vibration (piezoelectric effect) during inhalation, thereby avoiding the failure of the electrostatic adsorption mechanism of the low-resistance moisture-proof respirator filter cotton due to the neutralization of the charge on the surface of the middle layer by water molecules in the air.

[0026] 2) The middle layer of this utility model is also provided with a hydrophobic and oleophobic film, thereby reducing the static electricity attenuation under high humidity and solving the problem of static electricity neutralization in high humidity environment.

[0027] 3) The filter material of the dust mask of this utility model forms a stable "dome" structure through concentric ring corrugations and radial rigid support ribs. Even if the filter cotton absorbs a large amount of coal slurry water underground, it can resist the negative pressure of air intake and will not collapse and stick to the air inlet, ensuring that the airflow channel is unobstructed.

[0028] 4) The three-dimensional corrugated structure of the filter material for the dust mask of this utility model significantly increases the surface area (by about 30%-50% compared to a flat plate), and the gradient filtration structure improves the dust holding capacity, resulting in high dust holding capacity and long service life.

[0029] The above description is only an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the low-resistance moisture-proof respirator filter cotton proposed in this utility model;

[0031] Figure 2 This is a schematic diagram of the structure of the filter material for the dustproof face mask proposed in this utility model;

[0032] Figure 3 This is a schematic diagram of the structure of the dustproof face shield of this utility model. Detailed Implementation

[0033] To further illustrate the technical means and effects adopted by this utility model to achieve its intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of this utility model application is provided in conjunction with the accompanying drawings and preferred embodiments.

[0034] Low-resistance moisture-proof respirator filter cotton example

[0035] like Figure 1As shown, this embodiment provides a low-resistance, moisture-proof respirator filter cotton, which comprises three layers from the outside in: an outer layer 1, a middle layer 2, and an inner layer 3. The outer layer 1 is composed of needle-punched cotton or hot-air cotton; the middle layer 2 is composed of tourmaline melt-blown nonwoven fabric; and the inner layer 3 is composed of high-basis-weight mesh or skeleton-like nonwoven fabric. This forms a composite filter cotton with a self-supporting three-dimensional structure, anti-collapse properties, and moisture resistance and flame retardancy.

[0036] When used underground in coal mines, when the wearer inhales, the external air containing coal dust particles first passes through the outer layer 1, where large particles are intercepted. Then, the airflow enters the middle layer, where the tourmaline meltblown nonwoven fabric carrying an electrostatic field efficiently captures the remaining fine respirable dust through both electrostatic adsorption and physical interception. Finally, the purified clean air passes through the inner layer 3 and enters the respiratory system. The entire process is efficient, low-resistance, and safe.

[0037] The edges of the outer layer 1, middle layer 2, and inner layer 3 can be fixed together by ultrasonic welding or environmentally friendly hot melt adhesive. The specific shape of the low-resistance moisture-proof respirator filter cotton can be determined according to the specifications of the materials used in the outer layer 1, middle layer 2, and inner layer 3. The outer layer 1, located on the windward side, is made of a loosely structured fibrous material. Its function is to intercept large coal dust particles and prevent premature internal clogging. With its coarse fiber and high porosity structure, the outer layer 1 is specifically designed to capture larger coal dust particles, providing efficient pre-filtration and thus slowing down the clogging rate of the core filter layer. The water electret in the middle layer 2 provides a high initial charge, and the tourmaline dynamically replenishes the charge using the airflow vibration (piezoelectric effect) during inhalation. The piezoelectric and thermoelectric effects of the tourmaline enable the middle layer 2 to maintain the charge on the fiber surface even in high humidity environments, solving the problem of high humidity failure. The inner layer 3, located on the face-facing side, uses a high-basis-weight stiffened spunbond nonwoven fabric or skeleton material as a shaping base for the three-dimensional structure. This prevents the inner layer 3 from deforming or breaking under the impact of breathing airflow and also prevents the loose fibers of the middle layer 2 from falling off and being inhaled by the user.

[0038] The low-resistance, moisture-proof respirator filter cotton provided in this embodiment has a gradient filtration structure. The large-pore structure of the outer layer 1 acts like a "sieve," preferentially intercepting most large coal dust particles and preventing them from directly impacting and clogging the densely woven middle layer 2. The middle layer 2 further filters the air through electrostatic adsorption and physical interception via ultrafine fibers carrying an electrostatic field. In this way, the middle layer 2 can focus on capturing the finest particulate matter that is most harmful to the human body. This "division of labor" design makes the total dust holding capacity far exceed that of a single-layer structure, the breathing resistance rises more gradually, and the service life of the filter cotton is extended.

[0039] In this embodiment, the low-resistance moisture-proof respirator filter cotton is in a planar shape after the outer layer 1, middle layer 2 and inner layer 3 are stacked.

[0040] In specific implementation, in order to reduce the risk of combustion of the low-resistance moisture-proof respirator filter cotton, a flame retardant finishing agent film 11 is provided on the outer surface of the outer layer 1. The flame retardant finishing agent film 11 has flame retardant properties, which provide basic safety protection for the entire filter cotton.

[0041] The flame-retardant finishing agent film is made of phosphorus-nitrogen-based flame retardants (such as ammonium polyphosphate APP) or water-based acrylic flame-retardant emulsions. Both the phosphorus-nitrogen-based flame retardants and the water-based acrylic flame-retardant emulsions are halogen-free and have low toxicity, making them suitable for respiratory protective equipment. The flame-retardant finishing agent film can be prepared using a foam coating or low-liquid-rate padding process, and then dried to obtain the final flame-retardant finishing agent film. The flame-retardant finishing agent mainly coats the fiber surface and does not clog the pores between fibers, thus having minimal impact on pore size and air permeability.

[0042] The outer layer (needle-punched cotton / hot-air cotton) has a pore size range of 60~300 micrometers (mainly intercepting large coal dust particles >50μm, serving as a coarse pre-filter). The needle-punched cotton / hot-air cotton is 60g / m² flame-retardant polyester needle-punched cotton.

[0043] The tourmaline meltblown nonwoven fabric is made by thoroughly mixing ultrafine tourmaline powder with PP meltblown special material in a high-speed mixer before meltblowing, and then adding them together to a meltblown extruder. During melt spinning, the tourmaline powder is evenly embedded inside the PP fibers and partially exposed on the fiber surface, thus forming functional meltblown fibers containing tourmaline particles. The tourmaline meltblown nonwoven fabric uses a hydroentangling electret process for charge loading. The high-efficiency hydroentanglement process ensures the ultra-high capture efficiency of respirable dust in the middle layer 2. Tourmaline is a natural polar crystal with piezoelectric and thermoelectric effects. That is, when subjected to small changes in breathing air pressure and body temperature, a potential difference is generated inside its crystal, forming a "miniature power station" that continuously replenishes and maintains the electrostatic charge of the surrounding PP fibers. Therefore, even in a humid environment with a large number of water molecules, its electrostatic field remains stable, thus ensuring constant filtration efficiency. The tourmaline meltblown nonwoven fabric is a 50g / m² hydroentangled meltblown fabric containing 3% tourmaline powder and treated with an oleophobic coating.

[0044] To prevent water molecules in the air from neutralizing the charge on the surface of the intermediate layer 2 in the high-humidity downhole environment, thus causing the "electrostatic adsorption" mechanism to fail, in this embodiment, a hydrophobic and oleophobic finishing agent film 21 is provided on the outer surface of the tourmaline meltblown nonwoven fabric to isolate external moisture. The hydrophobic and oleophobic finishing agent film 21 can resist oil mist and moisture that may exist downhole. Specifically, the hydrophobic and oleophobic finishing agent film 21 is made of fluorinated acrylate copolymer. Further, the hydrophobic and oleophobic finishing agent is a C6 fluorocarbon resin type finishing agent, whose chemical nature is a fluorinated acrylate copolymer emulsion.

[0045] In this embodiment, the hydrophobic and oleophobic finishing agent film 21 constructs a charge isolation barrier to prevent electrostatic leakage caused by environmental moisture. Simultaneously, the piezoelectric charge generated by the tourmaline under stimulation is effectively accumulated in the hydrophobic and dry microenvironment. The two work synergistically to achieve long-term electrostatic adsorption in high-humidity environments. This is a dual mechanism of "shielding + energy replenishment." Specifically: 1) Water shielding: Downhole humidity reaches 90% RH, and ordinary meltblown fabric surfaces adsorb water molecules to form a microscopic conductive water film, causing static charge escape. The C6 fluorocarbon finishing agent reduces the fiber surface energy, preventing water vapor from spreading and forming a film on the fiber surface (similar to the lotus leaf effect), thus cutting off the charge escape pathway; 2) Piezoelectric energy replenishment: During air intake, the airflow generates micro-vibrations through the filter cotton, causing the tourmaline crystals to deform under pressure (piezoelectric effect), generating a weak potential difference and releasing negative ions or charges; 3) Synergistic effect: The hydrophobic film not only protects the original static charge but also protects the tourmaline particles from being encapsulated and rendered ineffective by coal slurry, allowing them to continuously generate new charges to replenish losses.

[0046] The tourmaline meltblown nonwoven fabric has a pore size of 1~20 micrometers (intercepting respirable dust and oil mist larger than 0.3μm, core filter layer).

[0047] Furthermore, to achieve the stiffening and shaping effect of the inner layer 3, the weight of the high-grammage mesh or skeleton nonwoven fabric is 50-80 g / m²; the material of the mesh or skeleton nonwoven fabric is polyester fiber and / or polypropylene fiber. The pore size range of the inner mesh or skeleton nonwoven fabric (spunbond nonwoven fabric) is 20-50 micrometers (mainly serving as support and preventing shedding, with good air permeability). The inner layer 3 is a 70 g / m² stiffened PET / PP bicomponent spunbond nonwoven fabric (providing rigidity).

[0048] The high-grammage mesh or skeleton nonwoven fabric is made of flame-retardant polyester fiber, flame-retardant nylon fiber, aramid fiber, or a mixture of one or more of the above fibers with polypropylene fiber.

[0049] Example of filter material for dust masks

[0050] like Figure 2 The dust mask filter material shown is made by hot pressing the low-resistance moisture-proof respirator filter cotton in the above embodiment. The edges of the outer layer 1, the middle layer 2 and the inner layer 3 are fixed together by ultrasonic welding or environmentally friendly hot melt adhesive. The dust mask filter material is hot-pressed into an outwardly protruding dome-shaped buffer part.

[0051] The low-resistance moisture-proof respirator filter cotton in the above embodiment is planar. After the low-resistance moisture-proof respirator filter cotton is placed in a mold and integrally hot-pressed, it forms the dust mask filter material of this embodiment. The dust mask filter material is dome-shaped and slightly protruding, with the edges still flat, which facilitates edge pressing and sealing.

[0052] Specifically, several concentric annular corrugations 4 are hot-pressed onto the filter material of the dust mask. The cross-section of the concentric annular corrugations 4 is trapezoidal or sinusoidal, and the height difference between the crests and troughs of the concentric annular corrugations 4 is 2mm to 8mm. In this embodiment, 3-5 concentric annular corrugations are pressed into the mold, with a crest height of 5mm, a corrugation pitch of 8mm, and 6 radial indentations (support ribs) evenly distributed along the circumference, each 2mm wide, and pressed deeply until the material is completely fused and hardened.

[0053] The center of the concentric annular corrugations 4 is the center of the filter material for the dust mask. At least four hot-pressed support ribs 5 are radially distributed on the filter material. The three layers of material at the hot-pressed support ribs 5 are fused together by high-density hot pressing to form a hardened skeleton. The four hot-pressed support ribs 5 extend and intersect at the center of the concentric annular corrugations 4. In this embodiment, the annular corrugations utilize the principle of arch mechanics, resulting in stronger radial compressive strength and resistance to deformation under high humidity and heavy absorption conditions; simultaneously, it increases the effective filtration area. The three layers of material at the support ribs are fused together by high-density hot pressing to form a hardened skeleton. The dust mask filter material with concentric annular corrugations 4 prevents the corrugations from flattening under negative pressure, ensuring the stability of the corrugation shape.

[0054] Example of filter material for dust masks

[0055] like Figure 3 The dust mask shown has an air inlet valve 101 on its main body 100. The main body 100 is provided with the dust mask filter material described in the above embodiment. The dome-shaped buffer portion is positioned opposite the air inlet valve 101, and the distance between the dome-shaped buffer portion and the air inlet valve 101 is at least 5 mm. Utilizing this three-dimensional structure, when the filter cotton is installed in the respirator, a buffer cavity with a constant volume is naturally formed between the inner surface of the filter cotton and the air inlet valve 101, thereby reducing the airflow velocity after passing through the filter cotton, allowing the airflow to be evenly distributed into the breathing valve, and reducing turbulent resistance.

[0056] When using the dust mask provided in this embodiment, the inhaled dusty, humid airflow impacts the filter cotton under negative pressure. The concentric corrugated structure disperses the airflow, increasing the contact area. As the airflow passes through the layers, it causes micro-vibrations in the tourmaline, releasing charges and adsorbing fine dust. Although the filter material becomes heavier due to moisture absorption, the radial support ribs lock the corrugated shape, and the inner layer 3 of the filter cotton maintains a raised dome shape, ensuring that a 5-8mm buffer cavity is always maintained between the inner side of the filter cotton and the air inlet valve 101. This not only prevents the filter cotton from becoming clogged but also creates a stable airflow zone, allowing the user to breathe more smoothly.

[0057] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the scope of the technical solution of the present utility model.

Claims

1. A low resistance moisture resistant respirator filter media, characterized in that, The filter cotton comprises three layers from outside to inside: The outer layer is composed of needle-punched cotton or hot air cotton; The middle layer is composed of tourmaline melt-blown non-woven fabric; The inner layer is composed of high gram weight reticulate or skeleton non-woven fabric.

2. The low-resistance moisture-proof respirator filter cotton according to claim 1, wherein The outer surface of the outer layer is provided with a flame-retardant finishing agent film; The pore size of the outer layer ranges from 60 to 300 microns.

3. The low-resistance moisture-proof respirator filter cotton according to claim 1, wherein The outer surface of the tourmaline melt-blown non-woven fabric is provided with a hydrophobic and oleophobic finishing agent film.

4. The low-resistance moisture-proof respirator filter cotton according to claim 3, wherein The material of the hydrophobic and oleophobic finishing agent film is fluorine-containing propylene-acrylate copolymer; The pore size of the tourmaline melt-blown non-woven fabric ranges from 1 to 20 microns.

5. The low-resistance moisture-proof respirator filter cotton according to claim 1, wherein The gram weight of the high gram weight reticulate or skeleton non-woven fabric ranges from 50 to 80 g / m2; The material of the reticulate or skeleton non-woven fabric is polyester fiber and / or polypropylene fiber; The pore size of the reticulate or skeleton non-woven fabric ranges from 20 to 50 microns.

6. The low-resistance moisture-proof respirator filter cotton according to claim 1, wherein The material of the high gram weight reticulate or skeleton non-woven fabric is flame-retardant polyester fiber, flame-retardant nylon fiber, aramid fiber or a mixture of one or more of the above fibers and polypropylene fiber.

7. A filter material for dust mask, wherein the filter material is made by hot-pressing the low-resistance moisture-proof respirator filter cotton according to any one of claims 1-5, and the edges of the outer layer, the middle layer and the inner layer are fixed together by ultrasonic welding or environmentally friendly hot melt glue, and the filter material is hot-pressed into a outwardly convex dome-shaped buffer part.

8. The filter material for dust mask according to claim 7, wherein a plurality of concentric ring-shaped corrugations are hot-pressed on the filter material, the cross section of the concentric ring-shaped corrugations is trapezoidal or sinusoidal, and the height difference between the peaks and valleys of the concentric ring-shaped corrugations is 2-8 mm.

9. The filter material for dust mask according to claim 8, wherein the center of the concentric ring-shaped corrugations is the center of the filter material, and at least four hot-pressed support ribs are radially distributed on the filter material, and the three layers of material at the hot-pressed support ribs are fused into a hardened skeleton by high-density hot pressing.

10. A dust mask, wherein an air inlet valve is provided on the body of the dust mask, and the filter material for dust mask according to claim 7 is provided on the body of the dust mask, the dome-shaped buffer part is arranged opposite to the air inlet valve, and the distance between the dome-shaped buffer part and the air inlet valve is at least 5 mm. ​ ​ ​ ​ ​

Images