JPH0252014A - Air filter for paint booth - Google Patents

Abstract

PURPOSE:To control the temperature rise in a coating booth and remove fine dust by using a laminate fiber mat consisting of a fiber layer having water absorbing fibers or moisture absorbing fibers and a fusion dense layer having heat fusion fibers as an air filter for a coating booth. CONSTITUTION:An air filter 1 for coating booth consists of a fiber layer 3 including 70% or more of water absorbing or moisture absorbing fibers on the upstream side 2 of air current and a fusion dense layer 6 including 80% or more of heat fusion fibers on the downstream side 5. In some cases, a laminate fiber mat provided with a fiber layer 4 of synthetic fibers, regenerated fibers or the like is used an intermediate layer. The water content in the air introduced into the coating booth can be absorbed and retained and also water content leakage into the downstream layer can be reduced by using said filter 1 to control the temperature rise in the coating booth. Problems such as uneven adhesion of a coating material, generating rust on the coating device and the like are not generated, and fine dust is removed and a finished surface without damages can be provided on a coated surface.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an air filter for painting booths, and more specifically, to an air filter with excellent water absorption and hygroscopicity used in painting factories for automobiles, machinery, etc. It's about filters.

(Prior Art) Conventionally, air filters used in painting factories for automobiles, machinery, etc. (hereinafter referred to as painting booths) have been made of acetate fibers, as shown in Japanese Patent Publication No. 58-41089, for example. A self-extinguishing system that maintains bulk by heat welding the fibers of a fiber mat made of a mixture of vinyl chloride and vinyl acetate copolymer fibers, and fixes the fibers together by adding a plasticizer that plasticizes and melts the acetate fibers. This air element is installed in the paint booth and is used to remove fine dust that has a negative effect on the painted surface and to constantly supply clean air to prevent dust from entering.

(Problem to be solved by the invention) However, since the above air filter cannot remove moisture contained in the air supplied into the painting booth, it may cause uneven adhesion of paint or cause the object to be painted to stagnate for a long period of time. If this happens, problems such as rusting on the painted surface may occur. Furthermore, in order to solve these problems, dehumidification equipment must be provided separately, resulting in problems such as increased equipment costs.

(Means for Solving the Problems) In order to solve the above problems, the present invention comprises a filter made of a laminated fiber mat having a multilayer structure of at least two layers from the upstream side to the downstream side of the airflow. An integrated fiber mat formed by laminating a fiber layer containing at least 70% of water-absorbing fibers or moisture-absorbing fibers on the side, and a fiber layer containing at least 80% of heat-fusible fibers on the downstream side of the airflow, Furthermore, by integrally bonding cheesecloth to the surface of the bottom layer on the downstream side of the fiber mat, it prevents moisture and dust from entering the painting booth, and prevents damage to the painted surface, rust, and uneven coating. The purpose of the present invention is to solve this problem by providing a paint booth air filter that can be used in a paint booth.

(Function) By adopting the above configuration, the present invention absorbs moisture contained in the air supplied into the painting booth by the water-absorbing fibers or porous, hollow moisture-absorbing fibers located in the upstream layer of the airflow. , water retention, and by providing an intermediate layer as necessary, it further enhances the ability to collect fine dust.
At the same time, it can exhibit a water retention function, and by providing a dense fused layer mainly made of heat-fusible fibers on the downstream side of the airflow, it reduces permeation and leakage of water absorbed and retained water,
Controls the rise in humidity inside the paint booth. Furthermore, by integrally providing cheesecloth on the surface of the lowest layer on the downstream side of the airflow, the filter can be applied to a roll filter that is resistant to various pressure stresses during use and easy to maintain.

(Example) Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a side sectional view showing one example of implementation of the present invention.

As shown in the drawing, the upstream side 2 of the airflow of the filter 1, which is composed of two or more laminated fiber layers, contains at least 70% of water-absorbing or moisture-absorbing fibers, such as Lanseer (water-absorbing acrylic fiber manufactured by Nippon Exlan Kogyo), and the remainder is Mixed fiber with low melting point polyester fiber selected from general chemical fibers such as polyester, nylon, acrylic, polyolefin type, vinyl chloride type, modacrylic, vinylon, polyurethane, etc. or low melting point chemical fibers, basis weight 80-1s O
A water absorption and water collection layer 3 is formed of a random or cross web of g/11 (4 is an intermediate layer, and 4 is an intermediate layer made of polyester, polypropylene, nylon, acetate, rayon, recycled cellulose, porous acrylic, hollow polyester, super water absorption layer). It is formed of a random or cross web with a basis weight of 80 to 150 g/% made of synthetic fibers, semi-synthetic fibers, regenerated fibers, etc. such as acrylic and super-absorbent cellulose, etc., individually or in a mixture of multiple types, and mainly in the inflowing air. It has the function of collecting fine dust contained in the upstream layer, and is composed of fibers with a smaller diameter than the upstream layer, but is not limited to this.It also has the function of a water-retaining layer,
The upstream layer and the intermediate layer are integrally intertwined by needle punching, but they may also be integrally joined by fusing heat-fusible fibers. In addition, the heat-fusible dense layer J6, which is mainly composed of heat-fusible fibers and arranged on the downstream side 5, is made of heat-fusible fibers such as Low melting point polyester fiber, polypropylene
A random or cross web made of chemical fibers containing at least 80% of fibers such as polyethylene fibers and copolyamide fibers is used, and the integrated upstream layer and intermediate layer are layered and the fibers are fused together by heating. They are bonded together and form a dense layer that becomes skinned by heat shrinkage, thereby forming the air filter for a paint booth of the present invention. In addition, for reinforcing the surface of the lowermost layer on the downstream side of the air filter, cheesecloth 7 or a synthetic resin net is thermally bonded with heat-fusible fibers contained in the downstream layer or thermally bonded by coating or impregnating the cheesecloth. They may be integrally provided using a synthetic resin or an adhesive.

FIG. 2 shows another embodiment of the present invention, in which a water absorption and water sampling layer 3 formed of water absorption fibers or a fiber layer containing moisture absorption fibers is formed on the upstream side of the air flow formed in the same manner as in the above embodiment, and a water absorption layer 3 is formed on the downstream side. It is constructed by integrally adhering a heat-sealable dense layer 6 mainly made of heat-sealable fibers and cheesecloth 7 to the surface of the lowermost layer on the downstream side, and can also be constructed without the intermediate layer. In the above example, if the content of water-absorbing or moisture-absorbing fibers contained in the fiber layer constituting the upstream side of the airflow is less than 70%, the water-absorbing performance is exhibited; This is undesirable because it causes rapid swelling and increases pressure loss. Furthermore, water retention is not sufficient, and absorbed water becomes water droplets and easily falls out of the filter. Furthermore, if the content of water-absorbing fibers exceeds 95%, the strength of the water-absorbing layer itself will not be sufficient, so a range of 70 to 95% is desirable.

In addition, the content of heat-fusible fibers included in the downstream layer was increased to 80%.
If it is less than 95%, it is not preferable because the effect of preventing water leakage to the downstream side will not be sufficient, and if it exceeds 95%, the degree of adhesion of the heat-fusible fibers will increase, and the space area will decrease, resulting in increased pressure loss. Therefore, it is desirable to adjust the content to a range of 80% to 95%.

Next, FIG. 3 shows the results of measuring the water absorption capacity of the air filter for a paint booth obtained in the above example. The weight of the air filter used in the test was 307.5g/
The content of water-absorbing fiber is 71g/% (content rate 70
%), and the pressure loss was measured in a state where water was sprayed to absorb and retain water, and the relationship between the amount of water adhesion and the pressure loss was determined. The pressure drop shows a gradual increase in pressure drop until the amount of water adhesion reaches about 800 g per square meter, and the pressure drop does not show a sharp increase up to about 10 times the water-absorbing fiber content. The middle point in the figure is 150℃ after the test.
The residual moisture content and pressure loss after being left to dry for 10 minutes were shown, indicating that the air filter of the present invention could be reused by an appropriate drying method.

FIG. 4 is a graph showing the test results under actual usage conditions, and shows the relationship between the amount of moisture attached and absorbed and the pressure loss when air with a humidity of 100% is passed through.

The amount of water attached and absorbed shows the same tendency as shown in Figure 3, and at point A in the figure, water droplets begin to fall from the filter.
Indicates that saturation has been reached. The exhaust humidity at this time was 87
%Met. Also, at point B, which is the relationship between the amount of adhesion and the pressure loss, one hour after A, it was confirmed that there was no change in the exhaust humidity, and that there was no change in water leakage to the downstream side of the airflow when the air was placed in a saturated state.

(Effects of the Invention) Since the present invention is configured as described above, the present invention absorbs and retains moisture in the air introduced into the coating booth, and reduces moisture leakage to the downstream layer. Increase in humidity is suppressed. Further, this invention has the effect that problems such as uneven adhesion of paint and rust on the painted surface do not occur, and even fine dust is removed, resulting in a finished surface without damage to the painted surface.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of the construction of an air filter for a paint booth showing one example of the implementation of the present invention, Fig. 2 is a schematic side view of the construction of an embodiment of the same, and Fig. 3 shows the water absorption amount and pressure loss. FIG. 4 is a curve diagram showing the relationship between water absorption amount and pressure loss under the same usage conditions. l・・・Filter 2... Upstream side 3... Water absorption and water retention layer 4... Intermediate layer 5... Downstream side 6... Heat-fused dense layer 7... Cheesecloth

Claims (1)

[Scope of Claims] 1. Consisting of two or more layers of laminated fiber mat, with a fiber layer containing at least 70% of water-absorbing fibers or moisture-absorbing fibers on the upstream side of the airflow, and at least heat-fusible fibers on the downstream side of the airflow. An air filter for a painting booth characterized by an integrally arranged heat-sealed dense layer containing 80%. 2 Consisting of two or more layers of laminated fiber mats, with a fiber layer containing at least 70% water-absorbing or moisture-absorbing fibers on the upstream side of the airflow, and an intermediate layer made of synthetic fibers, semi-synthetic fibers, recycled fibers, or mixed fibers thereof. 1. An air filter for a paint booth, characterized in that a fiber layer formed by the above-mentioned fiber layer is integrally disposed on the downstream side of the gas, and a heat-sealable dense layer containing at least 80% heat-sealable fibers is integrally arranged. 3. The air filter for a paint booth according to claim 1 or 2, wherein cheesecloth is integrally adhered to the surface of the lowermost layer of the downstream side layer of the airflow.