JP2020110762A - Functional filter - Google Patents

Abstract

To provide a functional filter composed so that an industrial design such as characters formed by an adhesive layer to indicate a replacement time is clearly displayed when reaching the replacement time when fine grains including silver are adhered and antimicrobial fine grains is imparted.SOLUTION: A functional filter 1 comprises: a filter layer 2 composed of a nonwoven fabric having adhered antimicrobial fine grains including silver and having a thickness of 1 to 2 mm and a basis weight of 20 to 50 g/m2; and an adhesive layer 3 formed to a part of one corner in the filter layer 2 by an adhesive and transparent or having the same color as or approximate color to that of the nonwoven fabric for sticking on an object. The adherence amount of the antimicrobial fine grains to that nonwoven fabric is set to be 0.01 to 5.0 g/m2.SELECTED DRAWING: Figure 1

Description

The present invention relates to a functional filter, and in particular, it is attached to an object such as an air conditioner (hereinafter, referred to as “air conditioner”) or an air purifier, such as a cover attached to an intake port or a room ventilation port, The present invention relates to a functional filter for filtering passing gas, and further to a functional filter having an antimicrobial function such as an antivirus function, an antibacterial function, an antifungal function and the like.

Conventionally, the intake port of an air conditioner and an air purifier, the ventilation port of a room, the ventilation port, etc. are alleviated from being contaminated with dust, and the intake port and A filter may be attached to the ventilation hole.

Patent Document 1 describes, as such an air-conditioner intake port filter, a non-woven fabric, and a pressure-sensitive adhesive layer formed on a part of one side of the non-woven fabric to simplify the attachment work.

Further, in Patent Document 2, by forming a character indicating a replacement time such as "replace it" on the one surface of the non-woven fabric with a colorless adhesive layer, dust dirt is accumulated and the replacement time comes. The filter for the air conditioner intake port is described so that it can be visually identified. In this filter, the non-woven fabric is generally white or light-colored, and the part of the non-woven fabric where the pressure-sensitive adhesive layer is not formed becomes black due to the accumulation of dust in the air as the air passes through the inside of the non-woven fabric. In contrast to the fact that it becomes soiled, air flow is suppressed in the area where the characters are formed with an adhesive, so that dust is less likely to accumulate inside the nonwoven fabric. As a result, while the filter is used over time, the non-woven fabric part where the adhesive layer is not formed is entirely discolored to black due to dust stains, whereas the characters formed of the adhesive will become white and the replacement time will be longer. It will be displayed by letters.

Further, Patent Document 3 describes an antibacterial filter in which photocatalytic fine particles such as titanium oxide are attached to a filter made of a non-woven fabric or the like in order to have an antibacterial function.

JP, 2013-154325, A JP, 2003-299923, A JP, 2000-107270, A

When the filter for the air conditioner intake port as described in Patent Document 1 or Patent Document 2 is provided with an antibacterial function to enhance the cleaning function for the air passing through the filter, the technique described in Patent Document 3 is used. It can be used. The filter to which the conventional technique of Patent Document 3 is applied utilizes the antibacterial property of the photocatalyst particles, but the photocatalyst also has a decomposing effect on synthetic resins and the like. For this reason, when the filter to which the photocatalyst particles are attached is used or stored for a long time in a state where it is exposed to light, the photocatalyst may adversely affect the pressure-sensitive adhesive layer, causing discoloration or deterioration of the pressure-sensitive adhesive layer. Also, due to deterioration of the adhesive layer, a part of the adhesive layer remains on the surface of the inlet cover when the filter attached to the cover attached to the inlet of the air conditioner is removed. May cause problems. Further, there is a possibility that the photocatalyst contained in the filter may also act on the cover of the intake port of the air conditioner to which the filter is attached in a similar manner to cause discoloration or deterioration thereof.

Therefore, in order to solve such a problem, in place of the photocatalyst particles, by attaching fine particles containing silver having an antiviral function such as an antiviral function, an antibacterial function, and an antifungal function to the filter, the antibacterial function is attached to the filter. I tried to give. As a result of a test, it was confirmed that the antimicrobial function was developed by depositing fine particles containing silver, but since the filter itself became gray or black, it gave the user the impression that it was dirty before use. It has been found that there is a problem in that it is difficult to display letters and the like formed of a colorless adhesive agent clearly even if dust is accumulated over time. As a result of investigating the cause, the particles containing silver having an antimicrobial function generally show black or gray in color, so that when the particles are attached to the filter, the filter itself turns gray. Was found. Therefore, even if the character indicating the replacement time is formed of the adhesive layer, there is a problem that it is difficult to determine the replacement time due to dust stains.

In view of the above conventional problems, the present invention is a design such as letters indicating the replacement time formed by the pressure-sensitive adhesive layer when the antimicrobial property is imparted by adhering fine particles containing silver, and the replacement time has arrived. Then, it aims at providing the functionality filter comprised so that it might be displayed clearly.

In order to achieve the above object, the invention according to claim 1 is a filter for adhering to an object and filtering a gas passing therethrough, wherein the antimicrobial fine particles containing silver are adhered and the thickness is A filter layer made of a non-woven fabric having a thickness of 1 to ² mm and a basis weight of 20 to 50 g/m ² , and a pressure-sensitive adhesive layer formed of a pressure-sensitive adhesive on a part of one surface of the filter layer for sticking to an object. The amount of the antimicrobial fine particles attached to the nonwoven fabric is in the range of 0.01 to 5.0 g/m ² .

According to this structure, the non-woven fabric having a thickness of 1 to 2 mm and a basis weight of 20 to 50 g/m ² that constitutes the filter layer filters dust and the like in the passing gas, and at the same time, antimicrobial fine particles as gas and dust and the like that have been adsorbed. Exerts an antimicrobial function against microorganisms present in. The pressure-sensitive adhesive layer provided on one surface of the filter layer can be attached to an object. When the functional filter is continuously used, the portion of the non-woven fabric where the pressure-sensitive adhesive layer is not formed has a large amount of gas flow, so that dust is accumulated due to the trapping of dust and the like to cause black stains. Since the gas is less circulated in the portion where the is formed, accumulation of dust and the like is suppressed. Since the adhesion amount of the antimicrobial fine particles containing silver to the non-woven fabric is in the range of 0.01 to 5.0 g/m ² , the non-woven fabric has a necessary antimicrobial function, and the color tone of the non-woven fabric changes due to the attachment of the antimicrobial fine particles containing silver. Since it can be suppressed, it becomes difficult to affect the discriminability of the replacement time by the pressure-sensitive adhesive layer formed on the nonwoven fabric.

According to a second aspect of the invention, in the constitution of the first aspect of the invention, the pressure-sensitive adhesive layer is transparent or has the same color or a similar color to the nonwoven fabric.

According to this structure, the pressure-sensitive adhesive layer is transparent or has the same or similar color as the nonwoven fabric.

According to a third aspect of the present invention, in the structure of the first or second aspect of the invention, at least a part of the area where the pressure-sensitive adhesive layer is formed in the filter layer is white or light-colored.

According to this structure, at least a part of the area of the filter layer where the accumulation of dust and the like is suppressed by forming the adhesive layer becomes white or light color.

According to a fourth aspect of the invention, in the configuration of the invention according to any one of the first to third aspects, the pressure-sensitive adhesive layer includes a display pressure-sensitive adhesive layer formed to display a replacement time.

According to this structure, when the functional filter is continuously used, even in the portion where the display pressure-sensitive adhesive layer is formed, the gas flow is small and the accumulation of dust and the like is suppressed.

According to a fifth aspect of the invention, in the constitution of the invention according to any one of the first to fourth aspects, the antimicrobial fine particles have at least one of an antiviral function, an antibacterial function, and an antifungal function. It has a function.

According to this structure, the functional filter exhibits at least one of antivirus function, antibacterial function, and antifungal function by the antimicrobial fine particles.

According to a sixth aspect of the invention, in the constitution of the invention according to any of the first to fifth aspects, the antimicrobial fine particles are fine particles of an inorganic compound containing silver and zinc.

The invention according to claim 7 is the constitution of the invention according to any one of claims 1 to 6, wherein the pressure-sensitive adhesive layer contains a two-component mixed polyurethane-based pressure-sensitive adhesive containing a main agent, a curing agent, and an ultraviolet absorber. The main agent contains a polyurethane polyol having a number average molecular weight of 15,000 to 25,000, the curing agent is contained in 6 to 8 parts by weight with respect to 100 parts by weight of the main agent, and the ultraviolet absorber is the main agent. It is contained in an amount of 0.25 to 0.5 parts by weight based on 100 parts by weight.

According to this structure, the pressure-sensitive adhesive layer is formed of a two-component mixed polyurethane-based pressure-sensitive adhesive, the main agent contains a polyurethane polyol having a number average molecular weight of 15,000 to 25,000, and the curing agent is 6 to 100 parts by weight of the main agent. Since 8 parts by weight is included, the pressure-sensitive adhesive layer has appropriate adhesive force and cohesive force. The ultraviolet absorber contained in the adhesive absorbs the ultraviolet light applied to the adhesive layer.

The invention according to claim 8 is the structure of the invention according to any one of claims 1 to 7, further comprising a release sheet laminated on the surface of the pressure-sensitive adhesive layer.

According to this structure, the surface of the pressure-sensitive adhesive layer is covered with the release sheet, and when the functional filter is used, the release sheet can be peeled off to expose the pressure-sensitive adhesive layer.

According to a ninth aspect of the present invention, in the configuration according to any one of the first to eighth aspects, the object includes a cover attached to an intake port of an air conditioner or an intake port of an air cleaner. ..

According to this structure, the functional filter is attached to the cover attached to the intake port of the air conditioner or the intake port of the air cleaner.

As described above, according to the invention of claim 1, since the nonwoven fabric has a thickness of 1 to 2 mm and a basis weight of 20 to 50 g/m ² , optimum filtration performance as a filter for an intake port of an air conditioner, an air purifier or the like is obtained. It works well and has the required strength. The fine particles containing silver generally have a black color, but by setting the amount of the antimicrobial fine particles containing silver to the nonwoven fabric to be in the range of 0.01 to 5.0 g/m ² , the nonwoven fabric is effective while the antimicrobial function is effective. It becomes easy to determine the replacement time by the pressure-sensitive adhesive layer formed on the. With continued use of the functional filter, the color density of the non-woven fabric changes due to the accumulation of adsorbed dust etc., but dust between the part where the adhesive layer is formed and the part where it is not formed in the non-woven fabric A difference in the degree of change in color density occurs due to the difference in the accumulated amount such as. By observing this difference in color density, the user can grasp or predict when to replace the functional filter. Therefore, in the present invention, the antimicrobial function and the discriminability of the replacement time of the functional filter are controlled by setting the adhesion amount of the antimicrobial fine particles containing silver to the nonwoven fabric in the range of 0.01 to 5.0 g/m ² . It is possible to achieve both.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, since the pressure-sensitive adhesive layer is transparent or has the same color or a similar color to the non-woven fabric, the pressure-sensitive adhesive layer is less visible from the surface, and the pressure-sensitive adhesive layer The color tone of the non-woven fabric is clearly displayed even in the portion where the is formed. Therefore, as the use of the functional filter is continued, the difference in the degree of color density change between the portion where the adhesive layer is formed and the portion where the adhesive layer is not formed in the non-woven fabric becomes clear. It becomes easy to determine the replacement time of.

According to the invention of claim 3, in addition to the effect of the invention of claim 1 or 2, at least a part of a region in which accumulation of dust or the like is suppressed by forming an adhesive layer is white or light-colored. Therefore, it becomes possible to clearly discriminate the difference in the degree of change in color density due to the successive use of the functional filter, and the user can appropriately discriminate the replacement time of the functional filter.

According to the invention of claim 4, in addition to the effect of the invention of any one of claims 1 to 3, in the filter layer, the periphery of the display adhesive layer becomes black and dirty due to accumulation of dust and the like. On the other hand, as a result of the accumulation of dust and the like being suppressed in the portion of the display adhesive layer, it becomes possible to visually recognize the form indicating the replacement time of the display adhesive layer. This allows the user to properly determine when to replace the functional filter.

In addition to the effect of the invention according to any one of claims 1 to 4, the invention according to claim 5 has an anti-virus function, an antibacterial function against a gas flowing through the functional filter and adsorbed dust, And, at least one of the antifungal functions can be exerted to clean the gas passing through the functional filter.

In addition to the effect of the invention according to any one of claims 1 to 5, the invention according to claim 6 has a long-term antimicrobial property because the antimicrobial fine particles containing silver are chemically stable. Since it can be maintained, the antimicrobial property and the discriminability of the replacement time can be compatible at a high level. Further, it does not adversely affect the physical properties of the pressure-sensitive adhesive layer and the object to be adhered.

According to the invention of claim 7, in addition to the effect of the invention of any one of claims 1 to 6, the pressure-sensitive adhesive layer has appropriate pressure-sensitive adhesive force and cohesive force. When it is attached to a cover attached to the intake port or the ventilation port in the room, it exhibits an adhesive force that does not easily fall off, and when removed, no adhesive residue is left on the cover surface. Since it contains an ultraviolet absorber, the durability of the pressure-sensitive adhesive against ultraviolet rays can be improved.

In addition to the effect of the invention described in any one of claims 1 to 7, the invention according to claim 8 has an adhesive layer covered with a release sheet, so that it is excellent in handleability before use and until use. The physical properties of the pressure-sensitive adhesive layer can be maintained well.

In addition to the effect of the invention according to any one of claims 1 to 8, the invention according to claim 9 is dust of gas passing through the air inlet of the air conditioner or gas passing through the air inlet of the air cleaner. Etc. can be filtered and an antimicrobial effect can be exerted on the passing gas to purify the passing gas.

It is a front view of the functional filter by a 1st embodiment of the present invention, (A) shows the state before the beginning of use, and (B) shows the state where the replacement time has come due to continued use. .. FIG. 2 is an enlarged cross-sectional view taken along the line II-II of FIG. 1, showing an exaggerated thickness. It is a front view of the functional filter by the 2nd Embodiment of this invention, Comprising: (A) shows the state before use start, (B) shows the state which the replacement time has come by continuous use. ..

[First Embodiment]
FIG. 1 is a front view of a functional filter according to a first embodiment of the present invention, in which (A) shows a state before the start of use and (B) shows a state in which a replacement time has come due to continued use. 2 is an enlarged cross-sectional view taken along the line II-II in FIG. 1, showing the thickness exaggeratedly.

First, an outline of the configuration of the functional filter 1 will be described with reference to FIGS. 1 and 2. The functional filter 1 is for sticking to an object (not shown) such as a cover attached to an air inlet of an air conditioner or an air purifier or a vent of a room to filter gas passing therethrough, A filter layer 2 made of a non-woven fabric, a pressure-sensitive adhesive layer 3 formed on a part of one surface of the filter layer 2 by a pressure-sensitive adhesive, and transparent or the same color as the non-woven fabric for sticking to an object, and a pressure-sensitive adhesive layer 3 The release sheet 5 is laminated on the surface of the. Further, the pressure-sensitive adhesive layer 3 includes a display pressure-sensitive adhesive layer 4 formed in a form in which characters or the like indicating the replacement time of the functional filter 1 are written (hereinafter, the pressure-sensitive adhesive layer in the filter layer 2 is formed. The surface 2b to be referred to is referred to as "back surface", and the opposite surface 2a is referred to as "front surface"). The pressure-sensitive adhesive layer 3 shown by the broken line in FIG. 1A showing the state before the start of use is actually hard to be visually recognized from the surface 2a of the filter layer 2.

In the functional filter 1 of this example, the antimicrobial fine particles containing silver are attached to the filter layer 2, and the amount of the antimicrobial fine particles attached to the nonwoven fabric is 0.01 to 5.0 g/m ² . The feature is that it is set in the range.

Next, each component of the functional filter will be described.

[Filter layer]
(1) Non-woven fabric: The non-woven fabric that constitutes the filter layer 2 preferably has a thickness of 1 to 2 mm, particularly 1.2 to 1.5 mm, in order to achieve both the capture of dust and the like and the flow of gas. It is preferably in the range of 20 to 50 g/m ² , particularly 30 to 40 g/m ² . When the thickness of the non-woven fabric is less than 1 mm or the basis weight is less than 30 g/m ² , there is a possibility that a sufficient dust trapping function may not be exhibited. If the thickness exceeds 2 mm or the basis weight exceeds 50 g/m ² , the gas flow resistance increases and the practicality as an air filter may be impaired.

As the constituent fibers of the non-woven fabric, any of natural fibers, synthetic fibers, and mixtures thereof can be used. Specifically, synthetic fibers such as polyester fibers such as polyethylene terephthalate (PET), polyamide fibers, polyimide fibers, copolymer fibers mainly containing polypropylene or propylene, and acrylic fibers containing modacrylic can be preferably used.

The method for producing the nonwoven fabric is not limited, and a nonwoven fabric produced by a known production method such as a chemical bond method or a thermal bond method can be preferably used.

The color of the non-woven fabric is such that it can be continuously used to recognize a state where darkening progresses due to accumulation of dust inside and on the surface of the non-woven fabric. In this embodiment, the entire nonwoven fabric is white.

(2) Antimicrobial Fine Particles The antimicrobial fine particles containing silver are fine particles containing silver, as long as they have an action of killing microorganisms such as viruses, bacteria and molds or an action of suppressing reproduction. The type is not limited. Usually, it is used in the form of supporting silver on a suitable organic or inorganic carrier. In this embodiment, as the antimicrobial fine particles containing silver, an inorganic compound containing silver and zinc, fine particles of silver/tungsten, silver/titanium oxide, iron/titanium oxide, etc. are used, but are not limited thereto. is not. However, even among them, since it is chemically stable and antimicrobial property can be maintained for a long period of time, it is possible to achieve a high level of both antimicrobial property and discriminability of the replacement time, and at the same time, the adhesive layer Fine particles of an inorganic compound containing silver and zinc are particularly preferable from the viewpoint of not adversely affecting the physical properties of the above and the object to be attached.

The method for adhering the antimicrobial fine particles containing silver to the nonwoven fabric is not particularly limited, and a known method can be adopted. For example, a method of dipping and adhering a nonwoven fabric in a binder resin solution in which antimicrobial fine particles are dispersed, a method of applying the above resin solution to the nonwoven fabric by spraying, a state in which the fiber surface of the nonwoven fabric is melted by heating. And a method of fixing the same by spraying fine particles containing silver on a non-woven fabric. Of these, dipping is preferable because the antibiotic fine particles can be evenly attached to the inside of the nonwoven fabric.

Since fine particles containing silver are generally gray or black, if the amount of adhesion is increased, the color tone of the non-woven fabric changes to gray due to the adhesion of antimicrobial fine particles containing silver, and the progress of dust stains on the non-woven fabric is recognized. May be difficult. Therefore, the amount of adhesion to the nonwoven fabric of antimicrobial particles comprising silver, range 0.01~5.0g / ^{m 2,} preferably from 0.016~3.0g / ^{m 2,} more preferably 0.05 By setting it in the range of up to 2.3 g/m ² , it is possible to achieve both the antimicrobial function of the filter layer 2 and the function of determining the replacement time by the adhesive layer formed on the nonwoven fabric. Become. If the adhered amount is less than the lower limit value of 0.01 g/m ² , the sufficient antimicrobial function may not be exhibited. When the upper limit of 5.0 g/m ² is exceeded, the surface 2a becomes gray before use, so even if dust or the like accumulates due to use, it is possible to determine the replacement time by the adhesive layer formed on the nonwoven fabric. It may be difficult to do.

[Adhesive layer]
An adhesive layer 3 is formed of an adhesive on a part of one surface (back surface 2b) of the filter layer 2. The pressure-sensitive adhesive used is not particularly limited, and a two-component mixed pressure-sensitive adhesive containing a main agent and a curing agent, a hot melt pressure-sensitive adhesive, or the like can be used. When using a two-component mixed adhesive, it is preferable to use a two-component mixed polyurethane adhesive. Further, if necessary, additives such as an ultraviolet absorber may be appropriately blended.

The color of the pressure-sensitive adhesive is preferably transparent, but may be the same or similar to that of the non-woven fabric. This makes it difficult to visually recognize the pressure-sensitive adhesive layer 3 when viewed from the surface 2a side of the filter layer 2 in a state before the start of use.

In this embodiment, a two-component mixed polyurethane-based pressure-sensitive adhesive containing a main agent, a curing agent, and an additive as exemplified below is used.

(Main agent)
The main agent contains a polyurethane polyol having a number average molecular weight of 15,000 to 25,000 (preferably 18,000 to 23,000) as a main component. The proportion of polyurethane polyol in the main agent is usually 95% by weight or more, and further 99% by weight or more. Therefore, the proportion of polyurethane polyol in the base material may be 100% by weight. The polyurethane polyol is obtained by reacting a polyester polyol and a polyether polyol with an organic polyisocyanate compound in the presence or absence of a catalyst, and known or commercially available products can be used. In selecting the polyurethane polyol to be used, the molecular weight can be measured using “Prominence” manufactured by Shimadzu Corporation (column: TOSgel TSKgel GMH×2 connected, detector: RID-10A, solvent: THF). , Flow rate: 1 ml/min).

(Curing agent)
For the curing agent, for example, aliphatic polyfunctional isocyanate or the like can be preferably used. The mixing ratio of the curing agent is 6 to 8 parts by weight with respect to 100 parts by weight of the main agent.

(Additive)
If necessary, an ultraviolet absorber, a filler, a colorant, an antioxidant, an antifoaming agent, a light stabilizer, etc. may be added to the two-component mixed polyurethane-based adhesive as long as the effect is not impaired. Agents can be added. Of these, it is particularly desirable to include an ultraviolet absorber. The addition amount of the ultraviolet absorber is appropriately set according to the desired characteristics, and can be, for example, in the range of 0.25 to 0.5 parts by weight with respect to 100 parts by weight of the main agent.

Regarding the main agent, the curing agent, and the additives, known or commercially available products can be used.

(Method for forming adhesive layer)
As a method for forming the pressure-sensitive adhesive layer on the nonwoven fabric, a known method can be adopted. For example, the pressure-sensitive adhesive may be directly applied to the nonwoven fabric, or may be indirectly applied by a method such as once applying the pressure-sensitive adhesive to the release sheet or the like and then contacting the release sheet with the non-woven fabric to transfer the pressure-sensitive adhesive to the non-woven fabric. After forming the coating film, a method of drying (solidifying) the coating film can be adopted.

The application method for directly or indirectly applying the pressure-sensitive adhesive layer to the non-woven fabric is not limited, but for example, a roller, spray, brush, printing or the like can be used. That is, for example, a roll coater method, a comma coater method, a die coater method, a reverse coater method, a silk screen method, a gravure coater method or the like using a known device can be adopted. In the case of applying indirectly, for example, after printing the pressure-sensitive adhesive on a release sheet coated with silicone with a roll or the like, by bringing the pressure-sensitive adhesive layer side of this release sheet into contact with a non-woven fabric and pressing with a roll or the like, A method of transferring the pressure-sensitive adhesive layer to the nonwoven fabric can be adopted.

When applying the pressure-sensitive adhesive (main agent or curing agent), the pressure-sensitive adhesive may be appropriately diluted with an organic solvent such as ethyl acetate, if necessary. The dilution ratio in this case is not limited, and for example, 1 to 30 parts by weight of an organic solvent may be added to 100 parts by weight of the main ingredient to dilute the main agent.

As a method for solidifying the applied coating film, any of a heating method, an ultraviolet ray method and the like can be adopted, but a heating method is particularly preferable. The heating temperature is not particularly limited as long as it is a temperature capable of forming a desired pressure-sensitive adhesive layer, but in the case of a two-component mixed polyurethane-based pressure-sensitive adhesive, it is usually set to 120 to 140°C, particularly 125 to 130°C. Is preferred. When a hot-melt pressure-sensitive adhesive is used as the pressure-sensitive adhesive, the hot-melt usually has fluidity at a high temperature, and therefore it is preferable to cool it to room temperature as opposed to heating.

(Applied area of adhesive layer)
The area ratio of the portion where the pressure-sensitive adhesive layer 3 is formed to the back surface 2b of the nonwoven fabric that constitutes the filter layer 2 is usually about 10 to 40%, and preferably 15 to 30%. If the area ratio is less than 10%, the adhesive strength may be insufficient, and if it exceeds 40%, the ventilation amount may not be secured.

(Thickness of adhesive layer)
The thickness of the pressure-sensitive adhesive layer after solidification can be appropriately set according to the adhesive performance required for the object, etc., and is usually in the range of 100 to 300 μm, particularly preferably 180 to 230 μm. If the thickness is less than 100 μm, it may be difficult to maintain the adhesiveness, and even if the thickness exceeds 300 μm, the adhesive performance does not change.

(Display adhesive layer)
A part of the pressure-sensitive adhesive layer 3 includes the display pressure-sensitive adhesive layer 4 formed in a form that indicates the replacement time. In this embodiment, the letter L of "replaced ne" and the mark M such as a heart are formed of an adhesive, but any letter or mark can be adopted. Further, the display pressure-sensitive adhesive layer 4 may be in the form of a simple stripe or lattice without containing characters or marks. In any form, if these parts can be visually recognized due to the accumulation of dust with time, they function as the display adhesive layer 4 indicating the replacement time.

Next, a usage mode of the functional filter 1 configured as described above will be described.

The functional filter 1 of this embodiment is applied to, for example, an air intake port of an air conditioner or an air purifier or a ventilation port of a room. Here, the case of application to the intake port will be described as an example. At the time of use, the release sheet 5 is peeled off to expose the pressure-sensitive adhesive layer 3, and the back surface side of the functional filter 1 is attached to a cover of the intake port or the like. The functional filter 1 has silver-containing antimicrobial microparticles attached thereto, but as shown in FIG. 1(A), the entire surface is white at the beginning of use and the pressure-sensitive adhesive layer 3 is transparent. The pressure-sensitive adhesive layer 3 is less visible from the 2a side. When the use is continued, the non-woven fabric captures dust in the passing air in the portion of the filter layer 2 where the pressure-sensitive adhesive layer 3 is not formed, and the darkness of the non-woven fabric progresses by accumulating the dust. On the other hand, in the portion of the filter layer 2 where the pressure-sensitive adhesive layer 3 is formed, the flow of air is suppressed, so that the accumulation of dust does not proceed, and the dust or the like does not accumulate much on the nonwoven fabric. As a result, as shown in FIG. 1(A), the characters L, marks M, etc., which were hardly discriminated before the start of use, become dusty in the surroundings as shown in FIG. 1(B) over time. As a result of the accumulation of such things as blackening, it becomes a blank state and it becomes possible to read clearly. In this way, when the accumulation of dust in the functional filter 1 progresses to a certain extent, characters or the like indicating the filter replacement time formed by the display adhesive layer 4 appear due to the color density difference with the surrounding portion, The user can be notified when the filter needs to be replaced.

Further, in the functional filter of this embodiment, since the antibacterial fine particles containing silver are adhered to the non-woven fabric forming the filter layer 2, the anti-virus function and the antibacterial function against the passing gas, the captured dust, etc. By exerting an antimicrobial function such as an antifungal function, the gas can be purified.

As described above, the functional filter 1 of this embodiment realizes both the antimicrobial function against the flowing gas and the display function of the display adhesive layer 4.

[Second Embodiment]
3A and 3B are front views of the functional filter according to the second embodiment of the present invention, in which FIG. 3A shows a state before the start of use, and FIG. 3B shows a state in which the replacement time has come due to continued use. It is shown.

Each material constituting the functional filter 11 of this embodiment is common to the functional filter 1 of the first embodiment, and therefore the differences will be described here.

In this functional filter 11, a white or light variable color region 12a is formed in a part of a filter layer 12 made of a non-woven fabric, and the other part is a gray or black invariant color region 12b. It is characterized in that the display pressure-sensitive adhesive layer 14 is formed on the side so as to form characters for indicating the time of replacement and the like. It should be noted that the display pressure-sensitive adhesive layer 14 shown by a broken line in FIG. 3A showing the state before the start of use is actually hard to be visually recognized from the surface of the filter layer 12.

The functional filter 11 configured as described above is used by being attached to, for example, a cover of an intake port of an air conditioner, an air purifier or the like. In the functional filter 11 at the start of use, as shown in FIG. 3A, the variable color area 12a is white and the invariant color area 12b is gray or black. When the use is continued, the darkening of the nonwoven fabric progresses due to the accumulation of dust in the area where the adhesive layer 3 is not formed in the variable color area 12a. On the other hand, in the part where the display adhesive layer 14 is formed in the variable color area 12a, the accumulation of dust does not proceed, and the non-woven fabric does not darken much. As a result, characters that could not be discriminated as shown in FIG. 3(A) before the start of use have a color density difference with the passage of time, and become blank as shown in FIG. 3(B). , Will be able to read clearly. It should be noted that the parts other than the display pressure-sensitive adhesive layer 14 in the variable color area 12a may be visually assimilated because there is no difference in color density from the surrounding invariant color area 12b due to accumulation of dust.

In this way, when the dust is accumulated on the functional filter 11 to some extent, a character or the like indicating the filter replacement time formed by the display adhesive layer 14 appears to notify the user of the filter replacement time. it can.

Further, in this embodiment, since the invariant color area 12b is gray or black, it is not necessary to consider coloring with silver. Therefore, it is possible to increase the adhesion amount of the antimicrobial fine particles containing silver in the non-color-changing region 12b more than that in the variable-color region 12a, thereby increasing the antimicrobial function.

In addition, the functional filter of the present invention can be applied to not only the air intake of an air conditioner or an air cleaner, but also a cover attached to a vent or a vent of a room.

In the first embodiment, the non-woven fabric forming the filter layer is white, but the non-woven fabric is not particularly limited in color as long as the change in the non-woven fabric due to accumulation of dust can be recognized. However, since many non-woven fabrics in general distribution are white or light-colored, they can be preferably used from the viewpoint of easy availability.

Further, a design such as letters or symbols is drawn in gray or black on the surface of the white filter layer by printing, or a display adhesive layer is formed on the back surface of the filter layer with a colored adhesive such as gray or black. By doing so, if dust accumulates with continued use, the surroundings of the design become darker and darker, and the color density difference that was present before use was reduced, making it difficult to see the design as the replacement time. It is also possible to configure.

Further, as the antimicrobial fine particles, together with the antimicrobial fine particles containing silver, copper, gold, in combination with other antimicrobial fine particles containing other metals having an antimicrobial function such as zinc or other antimicrobial components Alternatively, the antimicrobial fine particles containing silver may contain these metals.

This example is mainly intended to be attached to the intake port of an air conditioner, and the filters of Examples 1 to 3 and Comparative Examples 1 to 4 were produced.
As a non-woven fabric constituting the functional filters of Examples 1 to 3 and Comparative Examples 1 to 4, a commercially available non-woven fabric mainly composed of polyethylene terephthalate fiber (unit weight: 30 g/m ² , thickness: 1.0 mm ±10% (nominal manufacturer value) ) Were prepared.

Then, as fine particles having antimicrobial properties, fine particles containing silver or fine particles made of titanium oxide were adhered to these nonwoven fabrics in an amount shown in Table 1 to remove fine particles from Examples 1 to 3 and Comparative Example 1. A non-woven fabric forming the filter of Comparative Example 3 was obtained. The original nonwoven fabric was used as it was as the nonwoven fabric composing the filter of Comparative Example 4.

In addition, in Examples 1 to 3 and Comparative Examples 1 and 2, as the fine particles containing silver, an inorganic compound containing silver and zinc having antiviral properties was used, and pyridine having antibacterial and antifungal properties was prepared. An attempt was made to impart antimicrobial properties by using together zinc pyrithione, which is one of the derivatives and is an organozinc complex (adhesion amount is fixed at 2.0 g/m ² ). Further, it was attempted to impart antimicrobial properties to the non-woven fabric constituting Comparative Example 3 by attaching fine particles of titanium oxide without using zinc pyrithione.

In order to form a pressure-sensitive adhesive layer on the non-woven fabrics of Examples 1 to 3 and Comparative Examples 1 to 4 thus obtained, a pressure-sensitive adhesive layer was formed on a silicone-coated release sheet by a roll coater method. After applying, the pressure-sensitive adhesive layer side of the release sheet is brought into contact with one side of the above-mentioned non-woven fabric and pressure-bonded with a roll to transfer and form the pressure-sensitive adhesive layer as shown in FIG. The filters of Examples 1 to 3 and Comparative Examples 1 to 4 were obtained by drying the adhesive layer.

As the pressure-sensitive adhesive layer constituting the present examples and comparative examples, a two-component mixed polyurethane-based pressure-sensitive adhesive containing a main agent, a curing agent, and an ultraviolet absorber was used, and the details are as follows.
-Main agent: polyurethane polyol having a number average molecular weight of about 20,000-Curing agent: 7.0 parts by weight per 100 parts by weight of main agent-UV absorber: 0.4 parts by weight per 100 parts by weight of main agent-Adhesive for non-woven fabric Area ratio of layers: about 20% of the total nonwoven fabric
・Thickness of adhesive layer (after drying): 200 μm±20 μm

As described above, for each of the obtained filters of Examples 1 to 3 and Comparative Examples 1 to 4, 1) antimicrobial function, 2) visibility of characters or the like indicating a replacement time that appears due to continued use, and 3) A test was conducted on the degree of adhesive residue on the pressure-sensitive adhesive layer.

"Anti-microbial function" is based on "ISO18184" for anti-virus function, influenza A virus (H3N2) was used as a test virus, and anti-virus activity value was 3 or more, ○3 Less than was evaluated as x.

Regarding the antibacterial function, the bacteria to be tested were Staphylococcus aureus and Escherichia coli according to "JIS1902", and those having an antibacterial activity value of 2 or more were marked with "○".

With respect to the antifungal function, a test was conducted in accordance with "JIS Z2911" by the dry method using the following four types of fungi.
Aspergillus niger NBRC 105649
Penicillium citrinum NBRC 6352
Chaetomium globosum NBRC 6347
Myrothecium verrucaria NBRC 6113

Regarding "Visibility of characters indicating the replacement time", the sample was attached to the intake port of the air conditioner (Panasonic CS-F368C2), and in this state, the air conditioner was operated in the operation mode = automatic operation mode, set temperature = 25°C. , Driving time = 8 hours/day x 3 months, and after 3 months, a sample in a dirty state is visually observed from a distance of 2 m to see if the displayed characters can be discriminated. Examined. Then, out of 10 observers, 8 or more could be discriminated, "○" was discriminated, 7 to 4 were discriminated, "△" was discriminated, and 3 or less were discriminated. It was judged as "x".

Regarding "adhesive residue on adhesive", with the sample stuck to the surface of a plate made of PS or ABS (both mirror surfaces), at 25°C and normal humidity, or at 40°C and 75% humidity After keeping the condition for 3 months, the condition after peeling from the plate was observed. When the functional filter is peeled off from the PS or ABS plate that is the object to be attached, the case where there is no visible adhesive residue on the object is evaluated as "○", and it remains slightly to the extent that there is no effect. When the adhesive residue was visible, the adhesive residue was visually recognized, and a state in which a new functional filter could not be attached unless a treatment such as wiping off the remaining adhesive was evaluated as “x”.

The test results are shown in Table 1 below.

表１の結果から、本発明は、優れた抗ウィルス機能、抗菌機能及び抗黴機能の発揮と、使用継続による埃等の蓄積により交換時期を示す文字等が明瞭に表示される機能との両立ができることが判る。更に、比較例３の酸化チタンからなる微粒子を用いたフィルターと比較して、上記の機能を備えつつ粘着剤の糊残りも生じない、実用性に優れた機能性フィルターを提供できることが判る。尚、本発明の実施例においては主にエアコンの吸気口への取り付けを想定した機能性フィルターを例示したが、埃等の汚れを抑制する目的で用いられるフィルターであって抗微生物機能を要求されるものであれば、上記に挙げた用途に限定されるものではない。

From the results of Table 1, the present invention has both excellent antiviral function, antibacterial function, and antifungal function, and a function of clearly displaying characters or the like indicating the replacement time due to accumulation of dust or the like due to continued use. You can see that Further, as compared with the filter using the fine particles of titanium oxide of Comparative Example 3, it can be seen that a functional filter having the above-mentioned function and having no adhesive residue of the adhesive can be provided, which is excellent in practicality. In the embodiments of the present invention, a functional filter mainly intended for installation in the intake port of an air conditioner was illustrated, but it is a filter used for the purpose of suppressing dirt such as dust and is required to have an antimicrobial function. The use is not limited to the above-mentioned applications.

DESCRIPTION OF SYMBOLS 1... Functional filter 2... Filter layer 2a... Front surface 2b... Back surface 3... Adhesive layer 4... Display adhesive layer 5... Release sheet 11... Functional filter 12... Filter layer 12a... Variable color area 12b... Invariable color area 14 Display adhesive layer The same reference numerals in the drawings indicate the same or corresponding portions.

Claims (9)

A filter for adhering to an object and filtering a gas passing therethrough,
A filter layer made of a nonwoven fabric having a thickness of 1 to 2 mm and a basis weight of 20 to 50 g/m ² , to which antimicrobial fine particles containing silver are attached,
Formed with an adhesive on a part of one surface of the filter layer, comprising an adhesive layer for sticking to an object,
A functional filter in which the amount of the antimicrobial particles attached to the nonwoven fabric is in the range of 0.01 to 5.0 g/m ² . The functional filter according to claim 1, wherein the pressure-sensitive adhesive layer is transparent or has the same color or a similar color to the nonwoven fabric. The functional filter according to claim 1 or 2, wherein at least a part of a region where the pressure-sensitive adhesive layer is formed in the filter layer is white or light-colored. The functional filter according to claim 1, wherein the pressure-sensitive adhesive layer includes a display pressure-sensitive adhesive layer formed to indicate a replacement time. The functional filter according to claim 1, wherein the antimicrobial fine particles have at least one function of an antiviral function, an antibacterial function, and an antifungal function. The functional filter according to claim 1, wherein the antimicrobial fine particles are fine particles of an inorganic compound containing silver and zinc. The pressure-sensitive adhesive layer is formed of a two-component mixed polyurethane-based pressure-sensitive adhesive containing a main agent, a curing agent, and an ultraviolet absorber,
The base resin contains a polyurethane polyol having a number average molecular weight of 15,000 to 25,000,
The curing agent is included in an amount of 6 to 8 parts by weight with respect to 100 parts by weight of the main agent,
The functional filter according to any one of claims 1 to 6, wherein the ultraviolet absorber is contained in an amount of 0.25 to 0.5 parts by weight with respect to 100 parts by weight of the main agent. The functional filter according to claim 1, further comprising a release sheet laminated on the surface of the pressure-sensitive adhesive layer. The functional filter according to any one of claims 1 to 8, wherein the object includes a cover attached to an intake port of an air conditioner or an intake port of an air cleaner.

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