KR102043286B1 - Development and Application of Moisture Absorbent for Automobile Lamps with Perforation Films - Google Patents

Abstract

The present invention relates to a moisture absorbent product for an automobile lamp. More specifically, the present invention relates to the moisture absorbent product which is placed inside a card headlamp to absorb moisture inside thereof and minimize the release of absorbed moisture at the same time, thereby being effective in suppressing condensation occurrence in the automobile headlamp.

Description

Dehumidifier for automobile lamp using perforated film and product using same {Development and Application of Moisture Absorbent for Automobile Lamps with Perforation Films}

The present invention relates to a hygroscopic product for automobile lamps. More particularly, the present invention relates to a hygroscopic product including a packaging material disposed in an automobile headlamp and effective in suppressing condensation in the automobile headlamp by absorbing moisture therein and minimizing the release of absorbed moisture.

As a means of securing the view of the vehicle, headlamps, rearlamps and fog lights may not perform their functions smoothly due to condensation.

In particular, when the temperature difference between the inside and outside of the component is large in a high humidity environment such as rain, when the lamp lens temperature is lowered, water inside the lamp is condensed and fine water droplets form on the surface of the lens, causing steaming. As a result, light scattering occurs, and it is difficult to secure a field of view. Accordingly, a means is required to prevent condensation from occurring even in external environmental factors such as temperature or climate change.

As such means, methods have been developed to provide a moisture absorbent in the headlamp or to prevent the generated moisture from affecting the lamp. Patent document 1 (Korean Patent Laid-Open Publication No. 2015-0062567) relates to a vehicle headlamp provided with a dehumidifying unit, and discloses a drain hole for discharging the moisture to the outside as a guide for forming a flow path through which moisture is moved. However, there is a limit in controlling moisture inside the headlamp, and the efficiency of preventing condensation due to a sudden external environment is not good.

The moisture absorbent can effectively control condensation in the headlamp by a simple method. However, when moisture is accumulated, the moisture absorbent can be easily re-released to increase humidity inside the headlamp and reduce condensation prevention efficiency. This may cause problems such as shortening the life of the lamp.

On the other hand, the method of increasing the moisture absorption capacity by adjusting the composition component of the moisture absorbent has been sought, but the efficiency is not good and there is a limitation in increasing the capacity. In addition, it is difficult to control moisture and there are technical limitations due to the limit moisture content.

In another aspect, attention is paid to the packaging material because the moisture absorbent is packaged inside the lamp. In other words, research and development of a technology for preventing condensation due to the interaction between the absorbent and the packaging material is required.

The present invention has been made to solve the above problems, it is provided in the car lamp to absorb the moisture in the interior and at the same time to release the absorbed moisture to facilitate the moisture control to efficiently generate condensation inside the lamp An object of the present invention is to provide a packaging material for an automobile lamp absorbent which can be suppressed and a moisture absorbent product for an automobile lamp including the same.

One aspect of the present invention relates to a moisture absorbent product for an automobile lamp comprising a packaging material including an inner layer of a breathable film and an outer layer of a perforated film, and a moisture absorbent including a hygroscopic material, a curable inorganic material, and a polymer additive in the packaging material.

In the moisture absorbent product for an automobile lamp according to an embodiment of the present invention, the perforated film may have a mean diameter of perforation of 0.01 to 2.0 mm and a perforation rate of 1 to 50%.

In the hygroscopic product for an automobile lamp according to an embodiment of the present invention, the perforated film may be a number of perforations 5 to 500 per unit area (cm 2).

In the hygroscopic product for an automobile lamp according to an embodiment of the present invention, the breathable film may be a high density polyethylene nonwoven fabric.

In the hygroscopic product for an automobile lamp according to an embodiment of the present invention, the perforated film may be a linear low density polyethylene film.

In the hygroscopic product for an automobile lamp according to an embodiment of the present invention, the breathable film may have a thickness of 10 to 200㎛.

In the hygroscopic product for an automobile lamp according to an embodiment of the present invention, the perforated film may have a thickness of 10 to 100㎛.

In the moisture absorbent product for an automobile lamp according to an embodiment of the present invention, the moisture absorbent may include 10 to 60% by weight of the hygroscopic material, 10 to 60% by weight of the curable inorganic material and 5 to 40% by weight of the polymer additive.

In the hygroscopic product for an automobile lamp according to an embodiment of the present invention, the hygroscopic material may include any one or more selected from the group consisting of magnesium chloride, calcium chloride and sodium carbonate.

In the hygroscopic product for an automobile lamp according to an embodiment of the present invention, the curable inorganic material may include any one or more selected from the group consisting of magnesium oxide and calcium oxide.

In the hygroscopic product for an automobile lamp according to an embodiment of the present invention, the polymer additive may include any one or more selected from the group consisting of waxes, starches and cellulose compounds.

Hygroscopic products for automotive lamps according to an embodiment of the present invention has a moisture absorption rate of more than 150% at 80 ℃, 95% relative humidity conditions, and after 48 hours moisture absorption under 100% relative humidity and left for 12 hours at 70 ℃ The release rate may be less than 10%.

The present invention includes a packaging material that maintains constant breathability, exhibits uniform ventilation throughout, and has excellent mechanical properties and heat resistance, thereby significantly increasing moisture absorption in the lamp and simultaneously not re-releasing the absorbed moisture. The control has an excellent effect. Furthermore, it is possible to effectively suppress the occurrence of condensation inside the lamp to implement excellent performance to secure the field of view.

In addition, the problem to be solved by the present invention is not limited to the above-mentioned problem, another task that is not mentioned will be clearly understood by those skilled in the art from the following description.

1 shows a cross-sectional view of a packaging material for a vehicle lamp absorbent according to an aspect of the present invention.
Figure 2 shows a front view of a packaging material for automobile lamp absorbent according to an aspect of the present invention.

Hereinafter, a moisture absorbing product for an automobile lamp according to the present invention will be described in detail. The invention can be better understood by the following examples. The following examples are for illustrative purposes of the invention and are not intended to limit the scope of protection defined by the appended claims.

Also, unless defined otherwise, all technical and scientific terms have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms used in the description in the present invention are only for effectively describing specific embodiments and are not intended to limit the present invention.

Also, the singular forms used in the specification and the appended claims may be intended to include the plural forms as well, unless the context clearly indicates otherwise.

In addition, throughout the specification, when a part is said to "include" any component, this means that it may further include other components, without excluding the other components unless otherwise stated.

The term “perforation” of the present invention may also include porosity as opposed to nonporous, and is understood to be perforated in the direction of film thickness throughout the specification.

The inventors of the present invention continue to study how to effectively prevent condensation in automobile lamps to secure a stable field of view and to ensure the performance of the lamps for a long time, and there is a limitation in the moisture control technology in the lamps, which relies on a conventional moisture absorbent. Became aware. Note that the moisture control technology is not made of the absorbent alone, but also affects the absorbent packaging material which interacts with the absorbent, and further studies on the absorbent product for automobile lamps, which can realize the absorbent performance more efficiently in combination with the absorbent. In the meantime, the packaging material including the inner layer of the breathable film and the outer layer of the perforated film, while controlling the perforation size, perforation rate and thickness of the perforated film and the combination of the specific components of the desiccant while reducing the amount of the absorbent, Of course, it was found that the anti-release properties were significantly improved to complete the present invention.

Moisture absorbent product for an automobile lamp according to an aspect of the present invention is to include a packaging material that can more efficiently implement the moisture absorption performance due to the moisture absorbent while being able to stably contain the moisture absorbent for automobile lamps.

Specifically, as shown in Figure 1, the absorbent for an automobile lamp according to an aspect of the present invention perforated film 20 laminated on the inner layer of the breathable film 10 and the upper surface of the breathable film in direct contact with the moisture absorbent It includes a packaging material containing an outer layer of.

The perforated film 20 is characterized in that the perforated in the film thickness direction as shown in Figs. The perforations 21 formed in the perforated film 20 have a property of facilitating the inflow of moisture in the automobile lamp to facilitate moisture control including moisture absorption of the absorbent. In addition, as the absorbent is filled according to the volume of the packaging material so as not to flow in the packaging material, the packaging material may be damaged by the expansion of the moisture absorbent absorbent, which is effective in that it can serve as a kind of buffer so as not to damage the expansion. to be.

The packaging material may implement more improved hygroscopic performance by controlling the diameter and the perforation rate of the perforations 21 of the perforated film 20. Specifically, the perforated film 20 may be an average diameter of the perforated 21 is 0.01 to 2.0mm, preferably 0.1 to 1.5mm, more preferably 0.5 to 1.0mm. It can be effective in maximizing the hygroscopic performance of the absorbent in the above range and to ensure the mechanical properties of the packaging material stability.

In addition, the perforated film 20 may have a perforation rate of 1 to 50%, preferably 2 to 45%, and more preferably 5 to 40%. In this case, the puncturing rate means a percentage of the sum of the total puncturing areas with respect to the unit area. The perforation range is controlled in the average diameter range of the perforation, according to the combination of the hygroscopic performance as well as the contents can be stably contained a moisture absorbent, and more effective in terms of improving the mechanical properties of the packaging material, etc. .

In addition, the perforated film 20 may have a number of perforations per unit area (cm 2) of 5 to 500, preferably 8 to 300, more preferably 10 to 200. Within the above range, more efficient hygroscopic performance may be realized by a combination of the puncturing diameter and the puncturing rate, but this is merely an example and is not limited to the numerical range.

The perforated film 20 is not limited to a material, but may be preferably a linear low density polyethylene (Linear low density polyethylene) film. Linear low density polyethylene is produced in a low pressure process, the length of the branch (branch) bonded to the carbon chain is a regular polyethylene, in combination with a breathable film has the effect of achieving excellent performance in terms of moisture control in the lamp.

The linear low density polyethylene may have a melting point of 110 to 130 ° C. In addition, the density is 0.92 to 0.93g / cc, the melt index (Melt Index) at 190 ℃, 2.16kg load conditions may be 2.0 to 5.0g / 10nim, but is not necessarily limited thereto.

The perforated film 20 may be formed by using a known means, including a perforated or formed through a mechanical perforation process after being formed as a perforated film or a non-perforated film.

The thickness of the perforated film 20 is not particularly limited, but may be 10 to 100 μm, preferably 20 to 80 μm, and more preferably 30 to 50 μm. The thickness range is more effective to realize the synergistic effect of the hygroscopic performance in combination with the diameter of the perforation, the perforation rate, which is only one non-limiting example, it is not limited to the numerical range.

The breathable film 10 is not limited significantly in the material within the range of physical properties to be achieved by the present invention, specific examples of high density polyethylene nonwoven fabric, polypropylene (PP, polypropylene), polyethylene (PE, polyethylene) nonwoven fabric, polyethylene It may include at least one selected from the group consisting of polyethylene terephthalate (PET, non-woven), paper and cloth. It is more effective to use a high density polyethylene nonwoven fabric in terms of further improving the moisture control properties in the lamp in combination with the perforated film, including excellent mechanical properties and heat resistance as a packaging material for automobile lamp absorbent material. The high-density polyethylene nonwoven fabric is commercially available, and may include Tyvek, but is not limited thereto.

In particular, in the case of using the polymer polyethylene nonwoven fabric as the breathable film 10, it is possible to further improve the moisture absorption rate, it has an excellent effect of the anti-release properties. Specifically, when the humidity in the lamp suddenly increases, while the perforated portion of the perforated film serves as a buffer during the moisture absorption process, moisture particles formed outside the pores of the polymer polyethylene nonwoven fabric do not accumulate and are absorbed by the absorbent contained in the packaging material. Can be further improved. In addition, although the moisture content of the moisture absorbent has a property to release as it is difficult to explain in theory, the polymer polyethylene nonwoven fabric has the effect of significantly lowering the release rate in combination with the perforated film of the outer layer.

Although the thickness of the breathable film 10 is not particularly limited, it may be 10 to 200㎛, preferably 20 to 180㎛, more preferably 30 to 150㎛. More preferably, the thickness ratio of the perforated film 20 and the breathable film 10 may be 3: 1 to 1: 5, preferably 2: 1 to 1: 4. In this range, by combining the diameter of the perforation of the perforated film, the perforation rate and the thickness of the perforated film, by controlling the moisture in the car lamp more effectively, including moisture absorption performance due to the absorbent, to secure the visibility and long-term stability of the lamp life Effective in the sense, this is only one non-limiting example and is not limited to the above numerical range.

The breathable film 10 is a laminated combination with the perforated film 20, unlike the packaging material processed using a coating liquid of ethylene vinyl acetate composition on the film used as a conventional absorbent packaging material, serves as a kind of spacer (spacer) Due to the perforated film, the moisture absorption rate and the ventilation are uniformly expressed throughout the packaging material, and the moisture permeability is maintained as well as the moisture control in the lamp is easily maintained by maintaining a constant breathability.

The packaging material may be prepared by laminating the permeable film of the inner layer and the perforated film of the outer layer by a known method. Specifically, it may be prepared by a thermal lamination method of bonding the two films by heat, but is not limited thereto.

According to an aspect of the present invention, the moisture absorbent may include (a) a hygroscopic material, (b) a curable inorganic material, and (c) a polymer additive.

The hygroscopic material (a) is intended to impart hygroscopicity, and the type may be used without being particularly limited as long as it can implement hygroscopic performance. Specific examples include, but are not limited to, magnesium chloride, calcium chloride, sodium carbonate, sodium phosphate, sodium hydrogen carbonate, sodium citrate, sodium oxalate, sodium sulfate, and the like. Preferably, any one or more selected from magnesium chloride, calcium chloride and sodium carbonate may be mentioned.

The moisture absorbent (a) may be included in an amount of 10 to 60% by weight, preferably 20 to 50% by weight, and more preferably 30 to 40% by weight, based on the total weight of the absorbent. It is effective in maximizing the hygroscopic performance within the above range and ensuring the stability of the hygroscopic agent, but this is only one non-limiting example and is not limited to the numerical range.

The curable inorganic material (b) is commonly used to prevent the moisture absorbent from liquefying by deliquescent property after moisture absorption, and may include any one or more selected from magnesium oxide, calcium oxide, and the like, but is not limited thereto. (B) In the case of magnesium oxide as the curable inorganic material, commercialized examples may include STARMAG 50, etc. of KONOSHIMA CHEMICAL.

The (b) curable inorganic material may be included in 10 to 60% by weight, preferably 20 to 50% by weight, more preferably 30 to 40% by weight relative to the total weight of the moisture absorbent. In the above range, but effective in suppressing the separation of the deliquescent absorbent without deteriorating the hygroscopic performance, this is only one non-limiting example, it is not limited to the numerical range.

The polymer additive (c) is used to secure moisture absorption performance and mechanical properties of the moisture absorbent and to improve viscosity and molding processability when manufacturing the moisture absorbent by extrusion or injection. Specifically, waxes, starches, cellulose compounds, etc. may be mentioned, but are not limited thereto. In one embodiment, the wax may be any one or more selected from polyethylene wax, polypropylene wax, polyamide wax, canova wax, paraffin wax, polytetrafluoroethylene wax, and the like. In the case of polyethylene wax, as an upgraded example, LH 1200, manufactured by SFC, may be used. In addition, the starch may be modified starches such as starch, hydrolyzed starch, cross-linked starch, and the like. The cellulose-based compound may be carboxymethyl cellulose (CMC). , Hydroxypropyl cellulose, ethyl cellulose, methyl cellulose, sodium carboxymethyl cellulose, cellulose acetate and the like, but is not limited thereto.

In addition, the (c) the polymer additive may further include a component such as a polymer flocculant in a range that does not inhibit the object of the present invention. Specifically, sodium 2-propene acid 2-propeneamide polymer (SODIUM 2-PROPENOATE 2-PROPENAMIDE POLYMER), but is not limited thereto. This is effective in terms of preventing the liquefaction of the absorbent due to the deliquescent property after absorbing, as well as to give the soft properties such as sponge when the absorbent is expanded after absorbing.

The polymer additive (c) may include 5 to 40% by weight, preferably 10 to 30% by weight, and more preferably 15 to 20% by weight, based on the total weight of the moisture absorbent. It is effective to implement the desired physical properties in the above range, but this is only one non-limiting example, it is not limited to the numerical range.

According to an aspect of the present invention, the moisture absorbent may include not only an excellent moisture absorption rate by including the above component combination, but also minimize the re-release of moisture absorbed under environmental conditions of high temperature and low humidity. In addition, by combining with the packaging material according to the present invention described above it is possible to implement the excellent hygroscopic performance and emission resistance characteristics in the driving environment of the automobile lamp, furthermore it is effective to ensure the lamp life stability.

The moisture absorption product according to an aspect of the present invention is not particularly limited in shape and size of the packaging material, and can be appropriately designed as necessary. For example, the two packaging materials described above may be opposed to each other, and the absorbent may be placed between two oppositely facing packaging materials and then sealed by heat-sealing.

Hygroscopic product according to an aspect of the present invention has a moisture absorption rate of 150% or more at 80 ℃, 95% relative humidity conditions, and then released for 10 hours at 70 ℃ for 12 hours after 100 hours at 100% relative humidity It may be less than%.

Hygroscopic products according to an aspect of the present invention is for an automobile lamp, specifically, can be usefully applied to the field of similar lamps, including automobile headlamp, rear lamp or fog lamp.

Hereinafter, the present invention will be described in more detail based on Examples and Comparative Examples. However, the following Examples and Comparative Examples are only examples for explaining the present invention in more detail, the present invention is not limited by the following Examples and Comparative Examples.

(evaluation)

(1) moisture absorption rate and moisture absorption rate

After the specimen was exposed for 10 days at 80 ° C. and 95% relative humidity using a thermo-hygrostat, the moisture absorption rate was calculated using Equation 1 below.

Moisture absorption rate (%) = (weight after exposure-initial weight) / initial weight × 100

In addition, by measuring the time when the moisture absorption rate reaches 100%, the ratio of the time to reach the moisture absorption rate on the basis of the 10 days of the specimen exposure period was defined as the following equation 2 was calculated.

Moisture absorption rate (%) = time to reach 100% / 10 days × 100

(2) release rate

The moisture release rate of the moisture absorbent products according to Examples and Comparative Examples under 100% humidity conditions for 48 hours and then stored in an oven at 70 ° C. for 12 hours was measured to calculate the release rate.

Release rate (%) = {initial moisture absorption (g)-moisture absorption after drying (g) / initial moisture absorption (g)} x 100

(Example 1)

A packaging material having a length of 100 mm and a width of 100 mm was prepared. The packaging material uses a Tyvek film (Dupont, 1056D) as a breathable film, and laminated a linear low density polyethylene film (LLDPE, Hanwha Chemical, 3324) as a perforated film on the breathable film, and then applied the film at 120 ° C. Was used. At this time, the perforated film has a number of perforations 10 / cm ² , A perforation average diameter of 1.0 mm was used. In addition, the thickness of a Tyvek film was 150 micrometers and the thickness of LLDPE was 40 micrometers.

As the absorbent, 25 g of the absorbent prepared by uniformly mixing 40% by weight of magnesium chloride, 40% by weight of magnesium oxide and 20% by weight of polyethylene wax (SFC, LH1200, softening point of 109 ± 3 ° C) using a mixer was used.

Using two sheets of packaging material to face each other, the moisture absorbent is placed therebetween, and then processed at a temperature of 120 ° C. using a heat sealing machine to prepare a hygroscopic product specimen. At this time, the sealing part of the packaging material was 5mm in length and width.

After preparing the prepared specimens, the physical properties were evaluated according to the evaluation items, and the results are shown in Table 1 below.

(Example 2)

Except for changing the thickness of the LLDPE used for the packaging material was carried out in the same manner as in Example 1 except that the specimen was prepared, the physical properties were evaluated according to the evaluation items and the results are shown in Table 1 below.

(Example 3)

Except for changing the number of perforations of LLDPE used in the packaging material to 42 / cm ² was prepared in the same manner as in Example 1 to prepare a specimen, and then evaluated the physical properties according to the evaluation items and the results are shown in Table 1 Shown in

(Example 4)

Except for changing the thickness of the LLDPE used for the packaging material 50㎛ was carried out in the same manner as in Example 1 to prepare a specimen, the physical properties were evaluated according to the evaluation items and the results are shown in Table 1 below.

(Example 5)

The number of perforations of the perforated film is 14 pieces / cm ² , Except for the use of the average diameter of 2.2mm was carried out in the same manner as in Example 1 except that the specimen was prepared, the physical properties were evaluated according to the evaluation items and the results are shown in Table 1 below.

(Comparative Example 1)

In Example 1, without using a perforated film, hot melt coating liquid [provided by multi-coating: 25% by weight of acrylic latex adhesive, 8% by weight of acrylic latex (resin), 8% by weight of hot melt adhesive including EVA, 55% by weight of toluene, curing agent 4% by weight] was applied on the Tyvek film, and then dried and manufactured in the same manner as in Example 1, except that the composite latex / tyvek structured packaging material was used, and then the physical properties were evaluated according to the evaluation items. The results are shown in Table 1 below.

(Comparative Example 2)

Except for using the absorbent used in Example 1, DESI-PAK 25g containing a bentonite-based absorbent as a conventional commercial hygroscopic product was prepared in the same manner as in Example 1 to prepare a specimen, and then according to the evaluation items Evaluation of physical properties is shown in Table 1 below.

Hygroscopicity (%) Absorption rate Emission Rate (%) Example 1 163 5.4 2.8 Example 2 182 18.6 4.4 Example 3 173 15.3 3.8 Example 4 169 7.3 2.6 Example 5 185 5.1 7.8 Comparative Example 1 139 25.2 12.8 Comparative Example 2 126 30.6 17.1

As shown in Table 1, the embodiments of the present invention showed a very high level of moisture absorption and at the same time the water absorption rate was confirmed that can be quickly responded even when the humidity in the lamp suddenly increased, the emission rate is also significantly lowered It can be seen that it has a release resistance. On the other hand, the comparative examples have a relatively low moisture absorption rate, and the water absorption rate is significantly lower than that of the examples. In addition, it was confirmed that the moisture resistance in the lamp is not easy to control because the discharge resistance is not good.

Through this, the automobile lamp hygroscopic product according to an aspect of the present invention was able to confirm the effect of controlling moisture in the lamp quickly and stably with excellent moisture absorption performance as well as excellent discharge resistance.

Although the preferred embodiment of the present invention has been described above, it is clear that the present invention can use various changes and equivalents, and can be applied in the same manner by appropriately modifying the above embodiment. Therefore, the above description does not limit the scope of the present invention as defined by the limitations of the following claims.

10: breathable film
20: perforated film
21: perforation

Claims (12)

A packaging material in which the inner layer of the breathable film and the outer layer of the perforated film in which the perforations are formed are thermally laminated;
A hygroscopic material comprising any one or more selected from the group consisting of magnesium chloride, calcium chloride and sodium carbonate in the packaging material; Curable inorganic material containing any one or more selected from the group consisting of magnesium oxide and calcium oxide; And a polymer additive comprising at least one selected from the group consisting of waxes, starches, and cellulose compounds.
Moisture absorption rate of 150% or more at 80 ℃, 95% relative humidity conditions, moisture absorption product for automotive lamps having a moisture emission rate of less than 10% after being left for 12 hours at 70 ℃ after absorbing for 48 hours under 100% relative humidity. The method of claim 1,
The perforated film is an average diameter of the perforation of 0.01 to 2.0mm, the moisture absorption product for automobile lamps having a perforation rate of 1 to 50%. The method of claim 1,
The perforated film is a hygroscopic product for automobile lamps having a perforation number of 5 to 500 per unit area (cm 2). The method of claim 1,
The breathable film is a hygroscopic product for a high-density polyethylene nonwoven fabric. The method of claim 1,
The perforated film is a hygroscopic product for automobile lamps are linear low density polyethylene film. The method of claim 1,
The breathable film has a thickness of 10 to 200㎛ hygroscopic products for automobile lamps. The method of claim 1,
The perforated film has a thickness of 10 to 100㎛ hygroscopic product for automobile lamps. The method of claim 1,
The moisture absorbent 10% to 60% by weight of the hygroscopic material, 10 to 60% by weight of the curable inorganic material and 5 to 40% by weight of the polymeric additives. delete delete delete delete

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