CN220841768U

CN220841768U - Waterproof breathable film with strong ultraviolet resistance and stain resistance

Info

Publication number: CN220841768U
Application number: CN202322658030.9U
Authority: CN
Inventors: 吴小三
Original assignee: Shenzhen Sanshi New Material Technology Co ltd
Current assignee: Shenzhen Sanshi New Material Technology Co ltd
Priority date: 2023-09-28
Filing date: 2023-09-28
Publication date: 2024-04-26
Anticipated expiration: 2033-09-28

Abstract

The waterproof breathable film with strong ultraviolet resistance and stain resistance comprises a microporous PET film, a microporous waterproof coating layer coated on the upper surface of the microporous PET film, non-woven fabrics attached to the microporous waterproof coating layer, and aluminum metal plating layers arranged on outer surface fibers of the non-woven fabrics, wherein the aluminum metal plating layers exist in a non-faceted mode; the aluminum metal coating is also provided with a polysiloxane coating, straight micropores distributed along the thickness direction are distributed on the microporous PET film, and the micropores on the microporous waterproof coating layer comprise finger-shaped microporous layers. The waterproof and breathable composite material has the advantages of good waterproof and breathable effects, uniform micropore density, easily-controlled pore diameter and easily-obtained raw materials, and can better ensure stable quality. And aluminum metal plating and polysiloxane coating are added in the waterproof breathable film structure, so that the ultraviolet resistance and ageing resistance of the waterproof breathable film are effectively improved, and the anti-fouling property of the waterproof breathable film is enhanced. The utility model can be widely applied to electronic products such as mobile phones, watches, sound equipment, notebook computers, intelligent wearing and the like.

Description

Waterproof breathable film with strong ultraviolet resistance and stain resistance

Technical Field

The utility model relates to the field of electronic products, in particular to a waterproof breathable film with strong ultraviolet resistance and stain resistance.

Background

The waterproof and breathable film is a sealing material widely applied to industrial or agricultural production and is widely applied to electronic products. Because the electronic product can generate heat in the using process, if the waterproof heat dissipation effect is poor, the working stability of the internal electric element is affected and the service life of the internal electric element is shortened.

At present, the waterproof and breathable film adopted in the market is made of non-woven fabrics or polytetrafluoroethylene materials. The former is mainly applied to the use scenes with lower protection requirements, can only be used in scenes such as water splash prevention, and can not meet the high requirements of water resistance, diving and the like. The latter in the consumer electronics or precision parts market; the domestic autonomous production of the polytetrafluoroethylene membrane still has the problems of difficult raw material acquisition, unstable membrane quality and performance and the like due to the influence of factors such as raw materials, equipment, manufacturing process and the like. In addition, the polytetrafluoroethylene waterproof breathable film manufactured by most domestic manufacturers has the problems of poor consistency of ventilation and protection levels, and the process is not provided with intuitive and reliable monitoring indexes and detection methods temporarily, so that the conditions of uncontrollable quality, customer loss and the like are easy to occur. And with more and more outdoor application scenes, new requirements are also put forward on the ultraviolet resistance, ageing resistance and anti-blocking performance of the waterproof breathable film and components thereof. When the existing waterproof breathable film is used outdoors, the waterproof breathable film is easy to age and short in service life under the irradiation of the sun. Although chinese patent No. 201920994596.X discloses a sun-proof waterproof breathable film, it adopts to pack in the second breathable film layer and has had the calcium carbonate filler, has all set up first breathable film layer in both sides again, prevents that the addition of calcium carbonate filler from leading to the film body to break, and the outside of two-layer first breathable film layer all is equipped with tensile weaving rete, has strengthened waterproof breathable film's tensile properties, and waterproof breathable film's outside is equipped with ultraviolet resistance layer and weather-proof coating, when outdoor use, can slow down the ageing rate of film body. But first ventilated membrane layer and second ventilated membrane layer are polytetrafluoroethylene rete, have ventilative volume, protection level uniformity relatively poor and the uncontrollable problem of quality, have used the multilayer heat-conducting glue to realize pasting in the membrane in addition, also can lead to the jam of air vent, influence the gas permeability, and structure and processing are complicated moreover.

So the existing waterproof breathable film can not meet the requirements of wide consumers.

Disclosure of Invention

Aiming at the problems and the defects, the utility model provides the waterproof breathable film which has the advantages of good waterproof breathable effect, uniform micropore density, easiness in controlling the pore diameter, high production speed, high production efficiency, easiness in obtaining raw materials, capability of flexibly adjusting the pore diameter and the pore density of micropores according to the product requirement, easiness in conversion into manufacturing procedures and finished product inspection indexes and capability of better ensuring stable quality. In addition, the aluminum metal coating and the polysiloxane coating are added in the waterproof breathable film structure, so that the ultraviolet resistance and ageing resistance of the waterproof breathable film are effectively improved, and the anti-fouling property of the waterproof breathable film is enhanced.

The technical scheme of the utility model is realized as follows:

The waterproof breathable film with strong ultraviolet resistance and stain resistance is characterized in that: the waterproof coating comprises a microporous PET film, a microporous waterproof coating layer coated on the upper surface of the microporous PET film and provided with compact micropores which cannot be accessed by water, non-woven fabrics attached to the microporous waterproof coating layer, and an aluminum metal coating arranged on the outer surface fibers of the non-woven fabrics, wherein the aluminum metal coating exists in a non-planar manner so as to ensure the air permeability of the non-woven fabrics; and a polysiloxane coating is arranged on the aluminum metal coating, wherein straight micropores arranged in the thickness direction are distributed on the microporous PET film, and the micropores on the microporous waterproof coating layer comprise at least one layer of finger-shaped microporous layer.

In order to enable the waterproof scene meeting the high requirements of water resistance or diving, the waterproof scene is further: the micropores on the microporous waterproof coating layer are two layers, and the microporous waterproof coating layer comprises a spongy microporous layer on the outer surface and a finger-shaped microporous layer facing the microporous PET film.

The aluminum metal plating layer can be arranged in a vacuum evaporation plating mode, an ion plating mode or an electroless plating mode. Preferably, the aluminum metal coating is coated on the outer surface fibers of the non-woven fabric by means of vacuum evaporation coating. The vacuum evaporation plating mode is that aluminum vapor is tightly adhered to non-woven fabric fibers, and can effectively avoid blocking ventilation holes on the non-woven fabric, so that the air permeability of the non-woven fabric is further ensured. The thickness of the aluminum metallization is typically 10nm-1um.

The microporous PET film is formed by etching a PET irradiation film, and the aperture of the microporous PET film is 0.1-10um.

The non-woven fabric is bonded on the microporous waterproof coating layer in a bonding mode of hot pressing bonding, dry type compounding or bonding by using an adhesive. Preferably, the lamination is performed by hot pressing.

Compared with the prior art, the utility model has the advantages that:

1. The waterproof breathable film main structure with the multilayer laminated microporous structure is formed by combining the microporous PET film formed by etching the PET irradiation film and the microporous waterproof coating layer, so that the waterproof breathable film main structure can provide support through the microporous PET film, and the structural strength is improved, so that the waterproof breathable film main structure can be placed under certain water pressure. The air permeability can be improved by adjusting the aperture of the microporous PET film, and the influence on the overall waterproof effect of the waterproof and breathable film is very little. Meanwhile, the hydrophobic capacity of the waterproof coating layer is obviously improved compared with that of the microporous PET film, and the water stain residue is reduced. In addition, the pore diameters and pore densities of the microporous PET film and the waterproof coating layer are controllable (for example, the pore diameters of the PET film can be finely adjusted by adjusting the concentration, the reaction temperature and the reaction time of etching solution, the pore diameters and the pore densities of the coating layer can be further adjusted by adjusting the PVP addition amount and the molecular weight in the waterproof coating, and the like), the microporous PET film and the waterproof coating layer can be flexibly adjusted according to the product requirements, and can be easily converted into a process and a finished product inspection index, so that the stable quality can be better ensured. The introduction of the microporous material coating layer enables the straight micropore aperture of the microporous PET film to be made larger and the air permeability to be better. The related parameter indexes are visual and controllable, and the data are easy to form.

2. The aluminum metal coating is introduced into the waterproof breathable film structure, the ultraviolet resistance is enhanced through the aluminum metal reflection effect and the heat insulation effect, the defect of insufficient weather resistance of organic materials such as non-woven fabrics, various resins in components and parts is overcome, the aging speed is slowed down, and the service life of the waterproof breathable film in the outdoor sunlight exposure environment is greatly prolonged. In addition, aluminum metal is attached to the fibers of the non-woven fabric in a vacuum evaporation plating processing mode, namely, aluminum metal is plated on the non-woven fabric fibers in a high-temperature steam mode under a vacuum environment and condensed, so that a thin aluminum metal layer is attached to the non-woven fabric fibers, a surface (film) which is not completely covered by the aluminum metal layer exists on the non-woven fabric, and ventilation holes between adjacent fibers on the non-woven fabric are not blocked, so that the influence on the ventilation property of the non-woven fabric is very small.

3. The polysiloxane coating is arranged on the surface of the aluminum metal coating, so that the aluminum metal coating can be effectively prevented from being oxidized and corroded, and the service life of the aluminum metal coating is prolonged. In addition, the polysiloxane has certain self-cleaning capability, and can effectively improve the antifouling and anti-blocking performance of the composite material.

4. The waterproof breathable film can be widely applied to shells of electronic products such as mobile phones, watches, sound equipment, notebook computers and intelligent wearing.

The utility model is further described below with reference to the accompanying drawings.

Drawings

FIG. 1 is a schematic diagram of an embodiment of the present utility model;

FIG. 2 is a schematic diagram of another embodiment of the present utility model;

FIG. 3 is an enlarged schematic view of the structure shown at A in FIG. 2;

FIG. 4 is an enlarged partial schematic view of the bottom structure of FIG. 1;

fig. 5 is a schematic view of a partially enlarged structure of the fiber on the nonwoven fabric after aluminizing.

Detailed Description

As shown in fig. 1 to 4, the waterproof breathable film with strong ultraviolet resistance and stain resistance comprises a microporous PET film 1, a microporous waterproof coating layer coated on the upper surface of the microporous PET film 1 and provided with dense micropores which cannot be accessed by water, a non-woven fabric 4 attached to the microporous waterproof coating layer, and an aluminum metal coating 5 arranged on the outer surface fiber of the non-woven fabric 4, wherein the aluminum metal coating 5 exists in a non-planar manner so as to ensure the breathability of the non-woven fabric, a polysiloxane coating 6 is arranged on the aluminum metal coating 5, straight micropores 11 arranged along the thickness direction are distributed on the microporous PET film 1, and the micropores on the microporous waterproof coating layer comprise a finger-shaped microporous layer 2. As shown in fig. 1. In order to make the paint layer resistant to higher water pressure and possess a deep waterproof property, it is preferable that the micropores of the microporous waterproof paint layer have two layers including a sponge-like microporous layer 3 on the outer surface and a finger-like microporous layer 2 facing the microporous PET film side, as shown in fig. 2. The large circles in fig. 4 are enlarged straight micropores 11, and dense micropores seen in the straight micropores are microporous structures on the microporous waterproof paint layer.

In order to make the air permeability of the non-woven fabric good, the aluminum metal coating 5 is coated on the outer surface fiber of the non-woven fabric 4 by a vacuum evaporation coating mode, and the thickness of the aluminum metal coating 5 is 10nm-1um.

The microporous PET film 1 is formed by etching a PET irradiation film, and the aperture of the microporous PET film 1 is 0.1-10um. The density of the holes can reach 10 ten thousand holes per square centimeter. Thickness 4.5u-100um (preferably 12 um).

The manufacturing method of the waterproof breathable film comprises the following manufacturing steps:

S1, preparing a waterproof paint layer: the weight percentage of the paint is as follows: fluororesin PVDF:11%; carbon black 0.5% -5%; PVP pore-forming agent: 0.1%; the balance being solvent DMAc (dimethylacetamide).

The preparation method of the coating comprises the following preparation steps:

An appropriate amount of DMAc (dimethylacetamide) was weighed into a vessel and carbon black was added. And (3) adding PVP pore-forming agent after full dispersion, and continuing to disperse for half an hour. Finally PVDF was added and stirred for three hours. And (3) placing the dispersed paint into ultrasonic waves for defoaming for 2 hours to prepare the fluororesin waterproof paint.

S2, using a PET irradiation film with the thickness of 12um as a base film, and coating a fluororesin waterproof coating with the thickness of 7 microns on the upper surface of the base film to form a coating film;

S3, placing the coating film into an extraction liquid (such as water) to solidify the fluororesin waterproof coating layer, extracting a pore-forming agent in the fluororesin waterproof coating layer by the extraction liquid, and then sending the coating film into an oven for drying, curing and forming, so that the fluororesin waterproof coating layer forms a microporous waterproof coating layer with compact micropores which cannot be accessed by liquid, and drying and rolling; the extraction mode is that pore-forming agents distributed in the fluororesin waterproof coating layer are extracted through water, so that compact finger-shaped micropores are formed in the fluororesin waterproof coating layer.

S4, after one side of the microporous waterproof coating layer of the coating film is attached to the release surface of the PET release film, immersing the PET release film in sodium hydroxide etching solution, wherein the temperature of the etching solution is as follows: etching for 15 minutes at 70 ℃ to enable the PET irradiation film to generate a microporous PET film with the aperture of 2 microns and the aperture density of 10 ten thousand per square centimeter, and the microporous waterproof coating layer and the etching solution are not mutually repelled and cannot be damaged;

S5, stripping the PET release film to obtain a waterproof breathable film main body;

s6, selecting 90g of non-woven fabrics, carrying out vacuum evaporation aluminizing on one side, wherein the thickness of an aluminum metal coating is 30nm, the aluminum metal coating is attached to the fibers of the non-woven fabrics and does not exist on the other side, as shown in FIG. 5, the air permeability of the non-woven fabrics is ensured, black lines in FIG. 5 are fibers, and gray parts on the fibers are plated with aluminum metal;

S7, coating a layer of polysiloxane coating on the aluminum metal coating of the non-woven fabric by using a 120-wire mesh rod in a roller coating mode, curing for 3 minutes at 150 ℃, and curing;

And S8, attaching the untreated surface of the non-woven fabric to the microporous waterproof coating layer of the waterproof breathable film main body prepared in the step S5 to prepare the waterproof breathable film with strong ultraviolet resistance and strong pollution resistance.

If the waterproof coating layer is required to have deeper waterproof performance, a procedure can be added after the step S2, namely, the coating film is sent into a micro negative pressure environment with fresh air circulation, and the vapor pressure in the environment is reduced, so that part of solvent in the fluororesin waterproof coating layer is volatilized, and the time is controlled within two minutes. The effect of adding the coating film into the micro negative pressure environment of fresh air circulation for a few minutes is as follows: by reducing the vapor pressure in this environment, partial volatilization of the solvent in the paint layer is promoted, so that the paint layer can withstand higher water pressure and has a deep waterproof property. Because the micro negative pressure of fresh air circulation can effectively reduce vapor pressure, the solvent volatilization amount can be increased in a short time. When part of the solvent in the coating layer volatilizes, the fluororesin, the pore-forming agent and the like occupy the position of the solvent due to the leveling effect. The micropores of the coating layer become more compact (especially the outer surface layer of the coating layer is more obvious, and the outer surface layer can form a spongy compact microporous layer) during the later extraction, and the pore diameter is also reduced (namely the pore diameter is reduced). As the pore diameter becomes lower, the surface tension of water is added, so that the liquid water cannot permeate the micropores of the coating layer, and a better waterproof effect is generated. Meanwhile, as the solvent volatilizes, the density of the coating layer becomes high, so that the strength of the cured coating layer is improved, the coating layer can resist larger water pressure, and the coating layer has the deep waterproof performance.

Although the utility model has been described with reference to specific embodiments, this description is not meant to limit the utility model. Other variations to the disclosed embodiments can be envisioned by those skilled in the art with reference to the description of the utility model, and such variations are intended to fall within the scope of the appended claims.

Claims

1. The utility model provides a waterproof ventilated membrane that ultraviolet resistance and resistance to staining are strong which characterized in that: including micropore PET film (1), coating in the waterproof dope layer of micropore that has the unable fine and close micropore of water of micropore PET film (1) upper surface, laminating non-woven fabrics (4) on waterproof dope layer of micropore, set up aluminium metal coating (5) on the surface fibre of non-woven fabrics (4), and this aluminium metal coating (5) exist with the non-faceted mode, set up one deck polysiloxane coating (6) on aluminium metal coating (5), wherein the straight micropore (11) that are arranged along the thickness direction are distributed on micropore PET film (1), micropore on the waterproof dope layer of micropore is including finger micropore layer (2).

2. The waterproof breathable film of claim 1, wherein: the micropores on the microporous waterproof coating layer are two layers, and the microporous waterproof coating layer comprises a spongy microporous layer (3) on the outer surface and a finger-shaped microporous layer (2) facing the microporous PET film.

3. The waterproof breathable film of claim 1, wherein: the aluminum metal coating (5) is coated on the outer surface fiber of the non-woven fabric (4) in a vacuum evaporation plating mode, and the thickness of the aluminum metal coating (5) is 10nm-1um.

4. The waterproof breathable film of claim 1, wherein: the microporous PET film (1) is formed by etching a PET irradiation film, and the aperture of the microporous PET film (1) is 0.1-10um.

5. The waterproof breathable film of claim 1, wherein: the polysiloxane coating (6) is coated on the aluminum metal coating (5) in a roller coating mode.