JP2019005501A - Odor sustained release agent and odor sustained release member - Google Patents

Abstract

To provide an odor sustained release agent capable of suppressing odor which human being feels in a room of a structure or a mobile or the like.SOLUTION: There is provided an odor sustained release agent containing polyethylene imine (PEI) or an odor sustained release member having PEI on at least a part of a surface. By allowing PEI existing on a member surface, an odor component is temporarily maintained by PEI, and release of the odor component becomes mild. By using the odor sustained release member, even when environment in atmosphere (humidity, temperature or the like) is suddenly changed, the odor component is not released quickly from the member surface and the human being do not feel strong odor. The invention is innovative in the point of achieving deodorization and odor suppression by making release of the odor component mild different from conventional methods with removal, decomposition or the like of the odor component.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an odor sustained release agent that can suppress odors felt by humans.

  When a person is inside a building such as a house or a moving body such as a car, the person may feel odor even without a strong odor source. This is because odor components released in minute amounts from the wall surface constituting the room, the surface of each member in the room, the surface of a heat exchanger (especially an evaporator) provided on the indoor side of the air conditioner (referred to as “air conditioner”), etc. This occurs when the human sense of smell is detected.

  As measures against such odors (deodorant measures, odor control measures), it has been conventionally made to adsorb, remove, decompose, etc. the odor components released into the room. For example, adsorption removal of odorous components using activated carbon or the like, decomposition of odorous components (organic matter) by photocatalysts, ions, deodorant components, and the like.

  In addition, in the case of a member (apparatus) that generates a large amount of condensed water on the surface, such as an evaporator for an air conditioner, it has a low affinity with odorous substances (odorous components) and has a hydrophilic property ((modified) polyvinyl alcohol) Etc.) is also proposed. The description relevant to this is, for example, in the following patent document.

Japanese Patent No. 2002-285139 Japanese Patent No. 2002-285140 JP 2003-3282 A JP 2004-293916 A

  When a hydrophilized evaporator as described in the above-mentioned patent document is used, the odor component absorbed and absorbed on the surface is washed away with the condensed water, and the odor component is difficult to accumulate on the surface of the evaporator. However, in reality, even if an evaporator having such a surface treatment is used, if an air conditioner is operated, a person may feel odor at a certain timing.

  In any case, the conventional deodorization measures are to remove, disassemble, and wash odor-causing substances (odor components) to reduce the amount (concentration) of odorous substances released into the atmosphere (in the space). However, the effect was not always sufficient.

  This invention is made | formed in view of such a situation, and it aims at providing the odor controlled release agent etc. which can deodorize or deodorize by the method (mechanism) different from the past.

  As a result of diligent research to solve the above-mentioned problems, the present inventor newly discovered that the presence of polyethyleneimine (appropriately referred to as “PEI”) on the member surface can suppress odors felt by humans. By developing this result, the present invention described below has been completed.

<Scented release agent>
(1) The present invention is an odor controlled release agent containing polyethyleneimine (PEI).

(2) The presence of PEI on at least a part of the surface of each member can suppress odors felt in a space such as a room. The mechanism for obtaining such an effect can be considered as follows from the present research.

  First of all, a person senses “odor” by detecting even a very low concentration substance (odor component) by smell. However, human olfaction does not feel the intensity of odors corresponding to the absolute amount (concentration) of odor components, but the amount (concentration) or quality of odor components (the ratio of each odor component mixed) has changed. Sometimes it is easy to feel odor.

  Next, the release (evaporation) of water from the surface is largely involved in the release of the odor component from the surface of the member. In addition, the odor component released from the member surface is often absorbed from the atmosphere into the water present on the member surface in addition to the organic component released from the inside of the member.

  Based on such findings and the results of the evaluation test described later, the PEI according to the present invention is present on the surface of the member to temporarily hold odor components and water and suppress their release, and the odor components are in the atmosphere. It is thought that it is made hard to make people feel odor by suppressing sudden release into the inside (that is, by slowly releasing the odor component).

<Smell controlled release member>
(1) The present invention may be not only an odor sustained release agent but also an odor sustained release member having PEI on at least a part of its surface.

(2) The odor controlled release member only needs to have PEI on at least the surface side. For example, the odor controlled release member may be a member surface-treated with the above-described odor controlled release agent, or a member molded with a raw material mixed with PEI. Etc.

<Others>
(1) PEI as used in the present invention includes modified PEI or modified PEI. For example, a part of the terminal group of PEI is an amino group, carbonyl group, carboxyl group, imide group, hydroxyl group, nitrile group, nitro group, sulfide group, sulfoxide group, sulfone group, thiol group, ester group, etc. It may be substituted with one or more groups.

(2) Unless otherwise specified, “x to y” in this specification includes a lower limit value x and an upper limit value y. A range such as “a to b” can be newly established with any numerical value included in various numerical values or numerical ranges described in the present specification as a new lower limit value or upper limit value.

It is a molecular structure diagram of polyethyleneimine. It is explanatory drawing which showed typically the mechanism which feels odor. It is a schematic diagram which shows the outline | summary of the apparatus used for the odor evaluation test. It is the graph obtained by the evaluation test which concerns on 1st Example. It is the graph obtained by the evaluation test which concerns on 2nd Example. It is a graph which shows the thickness of the hydration layer in the surface of the test material used for the evaluation test.

  One or two or more components arbitrarily selected from the present specification may be added to the above-described components of the present invention. A method component can also be a component of an object in certain cases. Which embodiment is the best depends on the target, required performance, and the like.

<< PEI >>
(1) Structure PEI has a molecular structure of (—CH ₂ —CH ₂ —NH—) n as shown in FIG. The amino group (—NH—), which is the main functional group, is a polar group, and the distance between adjacent areas (distance between adjacent N) is about 3.7 mm. The molecular diameter of water is about 2 mm.

(2) Water characteristics PEI exists so as to grow on the surface of the member (base material), and includes 1 to several molecules of water as shown in FIG. 2 (2). The water contained by PEI is electrically strongly bonded to PEI and does not easily separate (evaporate, desorb, etc.) from PEI unless heated to a boiling point or higher even when heated to a high temperature. On the other hand, on the surface side, condensed water (condensed water) that can move freely is easily generated or evaporated according to changes in the environment (temperature and humidity of the atmosphere) to which the member surface is exposed. To do.

  In the present specification, as appropriate, water that is contained in PEI and is not easily released is “bound water”, water that is easily generated on or evaporated from PEI is “free water”, Water in the transition zone that exhibits intermediate characteristics between the two is called “intermediate water”.

(3) Odor Characteristics The odor component can be released on the surface of the member as shown in FIG. First, when there is no PEI on the surface of the member, as shown in FIG. 2 (1), the odor component is dissolved, absorbed, or concentrated in free water (for example, condensed water such as condensed water) generated on the surface of the member. It becomes a state. When free water evaporates due to a decrease in humidity or temperature increase in the atmosphere to which the surface of the member is exposed, an odorous component is also released into the atmosphere at the same time as the free water evaporates. Thereby, the density | concentration of the odor component in atmosphere increases rapidly, and the person in it comes to feel odor strongly.

  Next, when PEI is present on the surface of the member, as shown in FIG. 2 (2), the odor component is dissolved and absorbed in free water generated on the surface of the member and is taken in. This is the same as the case where the PEI described above does not exist.

  However, many of the absorbed and concentrated odor components are organic substances, and are often macromolecules having polarity, and many of them are in a state where the polar groups of PEI are supplemented by electric attraction. It becomes. As a result, even if the free water on the PEI evaporates, the odor component is not released at the same time. This is one of the differences from the case where no PEI exists as shown in FIG.

  Further, the intermediate water remaining in the vicinity of the PEI after the evaporation of the free water is less likely to evaporate than the free water, and the combined water contained in the PEI hardly evaporates. Therefore, the odor component moved (distributed) to the intermediate water or the combined water by evaporation of the free water is not released into the atmosphere at once. This is also one of the differences from the case where no PEI exists as shown in FIG.

  In addition, when PEI is present, odor components continue to be gradually released as free water and intermediate water evaporate. Therefore, when PEI is present, the odor component is not excessively concentrated in the intermediate water or bound water. When free water or intermediate water evaporates and free water is generated again, a part of the odor component temporarily held in the intermediate water or combined water moves to the free water (distributed). ), The overall state is in equilibrium. Therefore, the concentration of the odor component is never excessive even in the free water generated again.

  Such a phenomenon is repeated on the PEI present on the surface of the member, and by acting synergistically, the odor component is not released into the atmosphere at once (that is, slowly released), and the person feels the odor strongly. This is thought to have been deterred.

(4) Molecular weight The reason why PEI expresses the sustained release action of odor components is due to the molecular structure of PEI described above. When the molecular weight of PEI changes, the thickness of the hydrated layer composed of bound water and intermediate water changes, and the sustained release effect of the odor component can also change. For example, as the molecular weight of PEI increases, the thickness of the hydration layer increases and the sustained release effect and thus the deodorizing effect tends to increase. Therefore, the molecular weight of PEI is preferably 300 to 70000, more preferably 400 to 35000. PEI with a molecular weight that is too low or too high is not readily available. Further, when the molecular weight is too small, the sustained release effect is weakened, and when the molecular weight is too large, the viscosity becomes high and adhesion to the substrate surface becomes difficult.

  The molecular weight as used herein is a well-known Z average molecular weight (Mz), and the molecular weight is calculated by Mz = ΣMi3Ni / ΣMi2Ni (Mi: each molecular weight, Ni: molecular number of molecular weight Mi).

<Scented release agent>
The odor controlled release agent may contain one or more polymers, solvents, surfactants and the like different from PEI alone, in addition to PEI alone. Examples of polymers mixed with PEI include polar functional groups such as amino groups, carbonyl groups, carboxyl groups, imide groups, hydroxyl groups, nitrile groups, nitro groups, sulfide groups, sulfoxide groups, sulfone groups, thiol groups, and ester groups. It is good to use what has 1 or more types.

  The odor controlled release agent may be mixed into the raw material of the member, but when it is adhered to the surface of the member to form a PEI film (layer), a sustained release effect can be obtained efficiently. As the adhesion method, a coating method, a dipping method, or the like is appropriately selected according to the form and characteristics of the member.

<Smell controlled release member>
The odor controlled release member is a member having PEI (film, layer) on at least a part of its surface. The odor controlled release member may be any of a raw material, an intermediate material, a final product (part), and the like. The material may be any of metal, resin, wood and the like, and the form may be a simple shape such as a plate shape, a block shape, a sheet shape, or a complex shape obtained by molding or processing.

  The specific use of the odor controlled release member is not limited as long as it is used to make it difficult for a person to feel odor. Typical applications of the odor-controlled release member include, for example, plate materials constituting indoor wall surfaces, building materials such as wallpaper, heat exchangers (especially evaporators through which air that flows into the room flows), and component materials (aluminum alloy plates, etc.) There is.

  Various samples with odor components attached thereto were prepared, and the odor generated from each sample was evaluated. The present invention will be described in more detail based on such specific examples.

[First embodiment]
"sample"
(1) Base Material A silicate glass plate (simply referred to as “glass plate” / sample 11) was prepared as a base material (test piece) to which an odor component was adhered. The base material size was 16 × 76 × 1 mm.

(2) Polymer film The surface of the glass plate was coated with a polymer film composed of PEI (simply referred to as “PEI film”). For film formation, glycidyltrimethoxysilane was introduced into the silanol group on the glass plate surface, and PEI was adhered to the glass plate surface.

(3) Odor Component Acetic acid, butyric acid, and trimethylamine (TMA) were used as the odor components to be attached to the substrate. Both are typical odor substances made of organic substances. Each base material was immersed in a mixed aqueous solution of these odor components (acetic acid: 1000 ppm, butyric acid: 100 ppm, TMA: 1000 ppm) for 3 days. The substrate pulled up from the mixed aqueous solution was sufficiently washed with pure water and then naturally dried indoors. Each sample thus obtained was subjected to odor evaluation.

"test"
The odor component release behavior of each sample was examined using a test apparatus as shown in FIG. Specifically, first, a sample to which an odor component was attached was placed in a glass chamber, and N ₂ conditioned using a mass flow meter and a humidifier was introduced into the chamber. This chamber was alternately immersed in a high temperature (30 ° C.) thermostat and a low temperature (2 ° C.) thermostat to change the environment in the chamber (temperature and humidity in the vicinity of the surface of each specimen). At this time, the high temperature holding time: 15 minutes, and the low temperature holding time: 15 minutes.

  The air that passed through this chamber and was led to the outlet was measured for humidity change and sensory evaluation (odor intensity evaluation). Along with this sensory evaluation, the air was collected in a collection tube, and the concentration analysis of each odor component was also performed using a gas chromatograph-mass spectrometer (GC / MS). The results thus obtained are also shown in FIG.

  The upper part of FIG. 4 shows the humidity of the air introduced into the chamber (WET / DRY), the holding temperature of the chamber, and the humidity of the air derived from the discharge port (sensory evaluation port). The middle and lower parts of FIG. 4 also show the sensory evaluation results and the GC / MS measurement results for sample 11 (with PEI film) and sample C0 (without PEI film / details will be described later). It was.

<Evaluation>
As is clear from FIG. 4, it was revealed that the release behavior of the odor component differs depending on the presence or absence of the PEI film. Specifically, the sample 11 with the PEI film showed a gentle change in both the odor component concentration and the sensory evaluation by GC / MS compared to the sample C0 without the PEI film. That is, it has been clarified that the odor component is gradually released by the PEI film, which makes it difficult to feel the odor.

[Second Embodiment]
"sample"
An aluminum alloy plate (simply referred to as “Al alloy plate” / sample C0) was prepared as a base material to which the odor component was adhered. This aluminum alloy plate is obtained by surface-treating an aluminum alloy (A1050) with a hydrophilic resin. The size of each substrate was 16 × 76 × 0.2 mm.

  In addition to the Al alloy plate (Sample C0), Sample 21 (PEI molecular weight: 600) and Sample 22 (PEI molecular weight: the surface of the Al alloy plate coated with a polymer film (PEI film) made of PEI having different molecular weights) 10,000). Each PEI film was formed in the same manner as in the first example.

  The odor component was made to adhere to each sample like the case of 1st Example. Each sample thus obtained was subjected to odor evaluation.

"test"
(1) The same sensory evaluation (odor intensity evaluation) as in the case of the first example was performed for each test material. The obtained results are also shown in FIG. The upper part of FIG. 5 shows the chamber temperature and the humidity at the discharge port (sensory evaluation port). The lower part of FIG. 5 shows the sensory evaluation results for each sample.

(2) Using an atomic force microscope (AFM: SPM-8000FM, manufactured by Shimadzu Corporation), which is a kind of scanning probe microscope (SPM), is on the surface of the specimen (before the sensory evaluation test) of each sample. The thickness of the hydration layer was measured. The results obtained by this are shown in FIG.

<Evaluation>
(1) As is clear from FIG. 5, the sample C0 without the PEI film showed a sharp peak odor intensity. On the other hand, in the samples 21 and 22 having the PEI film, the odor intensity was significantly reduced, and the change in the odor intensity became gentle. This tendency was more prominent for samples with a larger amount of amino groups introduced.

(2) From FIG. 6, it was found that the thickness of the hydrated layer generated on the surface of the test material was sample C0: 9 nm, sample 21:30 nm, and sample 22: 50 nm. As a result, it became clear that as the molecular weight of PEI increased, the thickness of the hydrated layer formed on the surface of the test material also increased, and the odor intensity was reduced and the change in odor intensity was suppressed. .

(3) Further, from FIG. 5, it was also clarified that the timing at which the odor intensity reaches the maximum (peak) is different for each sample. Specifically, in the sample C0 without the PEI film, the odor intensity was maximized in the vicinity where the humidity at the discharge port was maximized. On the other hand, in the samples 21 and 22 having the PEI film, the odor intensity was maximized after a time when the humidity at the discharge port was maximized. As described above, the maximum values of the samples 21 and 22 were significantly reduced as compared with the sample C0.

(4) The reason why such a tendency is obtained is considered as follows. In the sample C0 without the PEI film, it is considered that the release of the odor component is linked to the evaporation of water from the surface of the test material. On the other hand, in the samples 21 and 22 having the PEI film, it is considered that the release of the odor component is not necessarily interlocked with the evaporation of water, and the odor component is gradually released (that is, gradually released) by the PEI film.

  In addition, as the sample is formed with PEI having a higher molecular weight, the maximum value of the odor intensity is reduced and the timing at which the odor intensity is maximized is delayed. One reason for this is considered to be that the higher the molecular weight of PEI, the thicker the hydrated layer can be formed on the substrate surface, and the more odorous components can be temporarily retained.

  In any case, the presence of PEI on the surface of the member causes the odorous component to be released slowly (slow release), and the odorous component is rapidly released even if the environment (humidity, temperature, etc.) in the atmosphere changes. It became clear that people strongly felt odor strongly.

Claims (3)

  An odor controlled release agent containing polyethyleneimine (PEI).   The odor controlled release agent according to claim 1, wherein the PEI has a molecular weight of 300 to 70000.   An odor controlled release member having PEI on at least a part of its surface.