JPH09313857A - Filter for air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent such a problem in a filter material for an air conditioner comprising a microfiltration layer and a reinforcing layer that when the reinforcing layer is formed as a low density to increase the life of the filter, enough rigidity is not obtd. because of the low density, which causes sticking of pleats when the filter is folded into pleats, and that the passage is decreased or the flow rate, is increased. SOLUTION: As for a reinforcing layer, a nonwoven fabric comprising a glass fiber prepared by wet paper making method with a polyvinylalcohol fiber binder is used. The nonwoven fabric is adhered to a microfiltration layer to obtain a filter material for an air conditioner. Thus, the obtd. filter material has low density but high rigidity so that when the material is folded into pleats, such a problem that the folded parts stick to each other to close the passage can be prevented. The obtd. filter material has low resistance for aeration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter medium mainly used for air-conditioning related filters for purifying general homes, buildings and automobile interiors.

[0002]

2. Description of the Related Art Generally, an air-conditioning filter has a structure in which a thin sheet of filter material is folded in a pleat shape and housed in a frame body in order to reduce air flow resistance and improve filtration efficiency and life. The thin sheet filter medium is generally constituted by joining a reinforcing layer for allowing the sheet to be folded into a pleat shape and a microfiltration layer for ensuring the filtration efficiency. Since the reinforcing layer has a density gradient structure for ensuring rigidity and extending filtration life, generally, a relatively thick chemical fiber is dry-woven into a non-woven fabric so as to have a low density, and then resin-processed. Further, as the microfiltration layer, in general, a spunbond or meltblown non-woven fabric made of ultrafine polypropylene fibers subjected to permanent electrification treatment is used in order to improve filtration efficiency with low air flow resistance. The joining of the reinforcing layer and the microfiltration layer is performed by making the reinforcing layer on the upstream side of the air flow and directly heat-melting and joining them in a spot shape, or between them by hot-melt powder. Commonly used.

[0003]

DISCLOSURE OF THE INVENTION In the conventional filter media,
The reinforcing layer needs to have a relatively low density as a density gradient structure in order to improve the filtration life, but the lower the density, the insufficient rigidity to fold it into a pleated shape, resulting in an increase in flow rate and clogging due to clogging. There is a problem in that the flow paths are reduced due to the close contact between them, and the ventilation resistance is likely to increase. In addition, in order to increase rigidity and impart flame retardancy, there are cases where resin processing is applied after making it into a non-woven fabric, but the density increases due to the drawing process to control the amount of adhesion, and the ventilation resistance Increase and decrease in filtration life occur.

[0004]

In order to solve this problem, the invention of claim 1 uses glass fibers as fibers constituting the non-woven fabric of the replenishment layer, and polyvinyl alcohol (hereinafter referred to as PVA).
It is produced by a wet method together with a fibrous binder. This reinforcing layer and a microfiltration layer similar to the conventional one are joined to form an air-conditioning filter medium.

According to the second aspect of the present invention, the non-woven layer of the reinforcing layer is composed of glass fibers and thermoplastic chemical fibers {for example, polyester (hereinafter referred to as PET) fibers} and wet-processed with a PVA fibrous binder. It is a thing. The reinforcing layer and the microfiltration layer are joined together to form an air conditioning filter medium.

According to a third aspect of the present invention, the reinforcing layer is composed of glass fibers or glass fibers and thermoplastic chemical fibers, is a wet-processed non-woven fabric, and the thermoplastic resin melted to bond the microfiltration layer is particulate. It was carried out by spraying.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Glass fibers are inorganic fibers, and have higher rigidity and are less flexible than chemical fibers generally used as a nonwoven fabric, such as polypropylene and PET. From this property, the non-woven fabric used for glass fiber is less flexible than general chemical fiber, so it is in a layered state so that it can be folded and combined into a rod shape, and even if it is wet-processed A low density state is secured. The PVA fibrous binder is mixed with glass fibers in an amount of 5 to 10% by weight with respect to the glass fibers at the time of papermaking, and joins the glass fibers in a drying step after the papermaking to prevent fiber separation. Since this non-woven fabric is mainly made of glass fiber,
Even if the density is low, the rigidity of the non-woven fabric itself becomes very high due to the characteristics of the fiber.

In general, a non-woven fabric made by a wet method is different from a dry type in that a short fiber of about 10 mm is used, and it is evenly dispersed in a large amount of water to make a paper. The formation is very good, and the partial deviation of the air flow is reduced, which is advantageous in terms of filtration performance.

Further, since the reinforcing layer is mainly composed of glass fiber which is an inorganic fiber, it has flame retardancy by itself, and performance deterioration and cost increase due to post-processing for imparting flame retardancy. There is no.

As described above, a nonwoven fabric having a low density, a high rigidity, a uniform texture, and a flame retardant property without post-processing is used as a reinforcing layer and is joined to the microfiltration layer to achieve high performance and low performance. It is possible to provide a costly air-conditioning filter medium. But,
The non-woven fabric of the reinforcing layer according to claim 1 has high rigidity, but when it is folded to form pleats, it does not have the flexibility of the glass fiber. Therefore, it is folded as sharply as possible so as to increase the filtration area of the filter. If you try to do so, the fibers themselves will be completely broken, and the folds will be cut off. Also, unlike the non-woven fabric composed of thermoplastic chemical fibers, you cannot heat set the folds after folding. There is a problem.

Therefore, the invention of claim 2 is the nonwoven fabric of the reinforcing layer, which is made of glass fibers and thermoplastic chemical fibers such as PET and is wet-processed together with the PVA binder. The reinforcement layer and the microfiltration layer are joined together to form a filter material for air conditioning.

In the invention of claim 1, the reinforcing layer is made of glass fiber, and in the invention of claim 2, the reinforcing layer is made of glass fiber and thermoplastic chemical fiber such as PET.

However, the non-woven fabric containing the inorganic fibers such as glass fibers melts the hot melt powder when the hot melt powder is used as the joining material when joining the microfiltration layer as the reinforcing layer. 100 to
It is necessary to apply heat of 150 ° C, and when the microfiltration layer is made of thermoplastic chemical fiber, the microfiltration layer shrinks at that time, and after joining, the filtration material rolls up on the microfiltration layer side, causing wrinkles. Folding may not be possible, or the folds may bulge and the creases may approach each other, leading to increased ventilation resistance and reduced filtration performance.

Therefore, in the third aspect of the present invention, in joining the reinforcing layer and the microfiltration layer, a thermoplastic resin such as polyethylene is melted in the reinforcing layer and is sprayed in a particulate form like a spray. Before the particulate molten thermoplastic resin is solidified, a microfiltration layer is attached and both are joined. The layer on which the thermoplastic resin is sprayed may be a microfiltration layer.

By using this method for joining the two, the microfiltration layer composed of the thermoplastic fibers does not undergo heat treatment afterwards, so that heat shrinkage does not occur, and the joined filter medium sheet is curled. And there is no problem when folding.

[0016]

EFFECT OF THE INVENTION In an air-conditioning filter material in which a reinforcing layer and a microfiltration layer are joined, the reinforcing layer is composed mainly of glass fiber and is made by a wet process, so that the density is low, the rigidity is high, the texture is uniform, and the post-processing is further processed. Even if it is not used, it will be a non-woven fabric with flame retardancy. Therefore, it is possible to provide a high-performance and low-cost air-conditioning filter medium having a low ventilation resistance, a long filtration life, stable filtration efficiency, and high rigidity while ensuring rigidity for folding in a pleated shape.

According to the invention of claim 2, the reinforcing layer is made of glass fiber and thermoplastic chemical fiber such as PET fiber, so that the same effect as that of the invention of claim 1 can be obtained. The breakage of the folded part due to processing does not occur, heat setting (buckling) of the folded part is also possible, and the folded part of the pleats can be made into an acute angle.

According to the invention of claim 3, while having the features of claim 1 or claim 2, after joining the reinforcing layer and the microfiltration layer, there is curling or wrinkling, which causes a problem in the folding process. Never wake up.

Therefore, depending on the application and the required specifications, it is possible to select a simple constituent material or a material that meets the required characteristics.

Claims (3)

[Claims] 1. An air-conditioning filter material comprising a microfiltration layer and a reinforcing layer which are superposed and joined to each other, wherein the reinforcing layer is a nonwoven fabric made of glass fiber and wet-processed with a polyvinyl alcohol fibrous binder. Filter media. 2. An air-conditioning filter material in which a microfiltration layer and a reinforcing layer are superposed and joined to each other, and the reinforcing layer is composed of glass fibers and thermoplastic chemical fibers, and is a non-woven fabric wet-processed with a polyvinyl alcohol fibrous binder. An air-conditioning filter medium characterized by the following. 3. An air-conditioning filter material in which a microfiltration layer and a reinforcing layer are superposed and joined to each other, and the reinforcing layer is made of glass fiber in a wet-processed non-woven fabric, or glass fiber and a thermoplastic chemical fiber in a wet state. An air-conditioning filter material comprising a non-woven fabric made into a paper, and a microfiltration layer and an auxiliary layer which are sprayed in the form of particles using a molten thermoplastic resin as a bonding material before they are solidified.