JP6807166B2 - Spray products - Google Patents

Description

The present invention relates to a spray product in which a spray can is filled with a liquefied gas and an absorber that absorbs and retains the liquefied gas.

Spray products filled with liquefied gas in a spray can provided with an injection port include, for example, a dust blower filled with an injection agent for dust removal, a torch burner filled with liquefied fuel, and the like. Due to the structure of these spray products that use liquefied gas, liquefied gas may leak from the injection port when used continuously in an inverted state. As a countermeasure, conventionally, a liquid retaining absorber is housed in a spray can to absorb and hold liquefied gas. As such an absorber, one mainly composed of cellulose fiber obtained by crushing wood pulp or used paper, or one formed by molding urethane foam or urethane foam is known.

In recent years, dimethyl ether (that is, DME) has been used as a propellant for dust blowers. DME and liquefied petroleum gas (that is, LPG) are also used as liquefied fuel in torch burners and the like. Spray products using such liquefied gas are required to improve safety during use.

Patent Document 1 proposes an absorber composed of crushed cellulose fiber aggregates and containing 45% or more of fine cellulose fibers having a fiber length of 0.35 mm or less as an absorber for a spray can. This absorber contains fine fibers obtained by crushing cellulose fibers by mechanical or chemical means, and is excellent in absorption performance and liquid retention. Further, Patent Document 2 discloses that a breathable lid-like member is arranged between a space on the injection port side in a spray can and an absorber made of a fiber aggregate formed by compression molding in a block shape. There is. The breathable lid-like member seals the surface of the absorber to secure a space on the injection port side and prevent the fibers constituting the absorber from scattering.

Japanese Unexamined Patent Publication No. 2008-180377 JP-A-2010-112400

However, since the absorber of Patent Document 1 uses a large amount of fine cellulose fibers, not only is it not easy to handle when the content is large, but also crushing of raw material fibers, molding of crushed fibers, filling into a spray can, etc. , Manufacture requires many steps. It was also found that the physical properties of the crushed fibers differ depending on the raw materials such as wood pulp and used paper, and the liquid retention property of the absorber in which the crushed fibers are aggregated differs. Even when a compression molded product of crushed fibers is used as in the absorber of Patent Document 2, the liquid retention property changes depending on the raw material fibers, the compression molding method, and the filling method in the spray can.

On the other hand, in general, it is conceivable to increase the filling amount of the fiber serving as the absorber to improve the liquid retention property, but the space volume in which the liquid can be retained in the absorber decreases. Further, in order to surely prevent liquid leakage, it is sufficient to fill the liquefied gas sufficiently smaller than the space volume in the absorbing body, but there is a possibility that the required filling amount of the liquefied gas cannot be secured. Alternatively, the size of the absorber or spray can is increased in order to increase the space volume in the absorber. Moreover, in order to stably produce an absorber having desired characteristics, it is necessary to control the process so that the raw material fibers and the manufacturing conditions are constant, and the raw material cost and the manufacturing cost increase and the productivity decreases. ..

On the other hand, the mechanism by which the liquefied gas is retained inside the absorber in which the crushed fibers are aggregated and the mechanism by which liquid leakage occurs during inverted use are not always known. For example, even if the amount of fibers to be the absorber is sufficiently large and the liquid retention property required in the storage state is obtained, the liquefied gas may leak out when the injection port is opened.
The present invention has been made in view of the above problems, and a sufficient amount of liquefied gas can be retained by using an absorber made of a fiber aggregate, and liquid leakage can occur even if sprayed in an inverted state. It is an attempt to provide a spray product that can be reliably prevented and has excellent safety and productivity.

One aspect of the present invention is formed between a spray can having an injection port on the head side, an absorber for liquefied gas and liquid retention filled in the spray can, and the absorber and the injection port. A spray product that has a space where vaporized gas collects.
The absorber is mainly composed of fiber aggregates made of crushed cellulose fibers, and voids in which the liquefied gas is held are formed between the fibers of the fiber aggregates.
The cellulose fiber contains at least one of wood pulp and waste paper pulp.
The volume of the liquefied gas exceeds 50% of the total volume of the spray can, and the total amount is held in the voids of the fiber aggregate.
The volume of the space portion is 4% or more of the total volume of the spray can.
In the spray can, the air permeability indicating the state of the ventilation path between the head side and the bottom side separated by the absorbent body in the liquid retention state is adjusted from the bottom side to the inside of the spray can. Using an air permeability measuring instrument including an air supply pipeline capable of supplying compressed compressed air and a flow meter arranged in the air supply pipeline, the absorber is used from the bottom side to the head side. A spray product has an air flow rate measured by the flow meter when an air pressure of 1.5 kPa is applied toward the spray product, and the air permeability is 1 L / min or more in terms of atmospheric pressure.

In the spray product, the fiber aggregate serving as an absorber physically holds the liquefied gas in the innumerable voids formed between the pulverized fibers by surface tension or van der Waals force. The spray can has a space of 4% or more of the total volume on the injection port side, and can collect a sufficient amount of vaporized gas for injection. Further, by configuring the absorber so that 50% or more of the total volume of the liquefied gas is held in the voids of the absorber, a sufficient amount of the liquefied gas can be retained in the product.

Further, the absorber ensures an air flow rate of 1 L / min or more in terms of atmospheric pressure between the bottom side and the head side to secure a release path when vaporized gas is generated. There is. Here, the mechanism by which liquid leakage occurs in conventional spray products is presumed as follows. When the injection port is opened while the absorber is in the liquid retention state, the pressure inside the spray can is reduced, so that the liquefied gas held in the absorber is vaporized. At this time, vaporization from the vicinity of the surface of the absorber is the main component, and the inside of the absorber that retains the liquid hardly allows gas to pass through. Therefore, if the vaporized gas generated near the bottom cannot escape to the injection port side, the head side The pressure on the bottom side tends to be higher than that. Therefore, the vaporized gas near the bottom acts like a piston, and the liquefied gas inside is pushed out.

On the other hand, the spray product of the present invention has a release path for the vaporized gas generated on the bottom side of the absorber even if the absorber holds a sufficient amount of liquefied gas and is filled in the spray can. , The vaporized gas quickly collects in the space on the injection port side. As a result, the pressure difference between the bottom side and the head side is immediately eliminated.
Therefore, even if the spray product is invertedly injected, the vaporized gas is continuously supplied to the space on the injection port side, and the liquefied gas is suppressed from leaking from the absorber, so that the injection can be safely continued. It will be possible. Further, in such an absorber, the raw material fiber is not limited and it is not necessary to use a large amount of fine cellulose fiber, so that the productivity is improved. Therefore, a spray product having excellent safety and productivity can be obtained.

FIG. 6 is an overall configuration diagram of a dust blower to which a spray product is applied according to the first embodiment. FIG. 5 is a configuration example of a dust blower according to the first embodiment, and is a cross-sectional view of a spray can in an upright state. FIG. 5 is a configuration example of a dust blower according to the first embodiment, and is a cross-sectional view of an inverted state of a spray can. Schematic cross-sectional view showing a shape example of a spray can. An enlarged cross-sectional view of a main part showing a shape example of a spray can. The figure which shows the relationship between the density and the liquid retention pressure of the fiber aggregate which constitutes an absorber. FIG. 2 is a configuration example of a dust blower according to a second embodiment, and is a cross-sectional view of a spray can in an upright state. FIG. 2 is a configuration example of a dust blower according to a second embodiment, and is a cross-sectional view of an inverted state of a spray can. The figure which shows the relationship between the density of the absorber and the apparent volume, the void volume, the liquefied gas residual volume and the liquefied gas injection volume in Example 3. FIG.

(Embodiment 1)
The first embodiment of the spray product will be described with reference to the drawings.
In FIGS. 1 and 2, the spray product of this embodiment includes a spray can 1 provided with an injection port 11, an absorber 2 for liquefied gas G and liquid retention filled therein, an absorber 2 and an injection port 11. It is provided with a space portion 3 having a predetermined volume formed between the two and where the vaporized gas collects. The absorber 2 is housed in the spray can 1 with a predetermined air permeability, which will be described later, and holds a predetermined volume of liquefied gas G inside the absorber 2. In the spray can 1, the side where the injection port 11 is provided (that is, the upper side in the figure) is the head H side, and the opposite side (that is, the lower side in the figure) is the bottom B side, and the vertical direction in the figure is the axis. The direction. Generally, when a spray product is used, as shown in FIG. 1, an injection portion 1a for opening and closing the injection port 11 is attached to the head H side of the spray can 1.

The spray product is used, for example, in a dust blower for dust removal, a torch burner for ignition, and the like. The dust blower is a product in which a propellant mainly composed of liquefied gas G is held in the absorber 2 and the vaporized gas of the propellant is sprayed onto an object to blow off dust and the like. The torch burner is a product in which a liquefied fuel composed of a liquefied gas G is held in an absorber 2, an injection port 11 is opened to eject a fuel gas, and a flame is formed by using an ignition device (not shown).

The liquefied gas G can be selected according to the application of the spray product. For example, dimethyl ether (ie, DME), which is a flammable liquefied gas, and liquefied petroleum gas (ie, LPG) are suitable for both propellants and liquefied fuels, and are used in a wide range of applications. Combustible liquefied gas or nonflammable liquefied gas other than these can also be used. These liquefied gases may be used alone or in combination of two or more, depending on the intended use, and a compressed gas other than the liquefied gas may be added. For example, DME has an extremely small ozone layer depletion potential of 0 and a global warming potential of 1 or less, and is useful as an propellant having a small environmental load. Further, flame-retardant carbon dioxide gas is added to increase the jet pressure. It can be a mixed liquefied gas. At this time, the mixing amount of carbon dioxide gas in the mixed liquefied gas can be arbitrarily selected. For example, the weight ratio is 30% or less, preferably 0.1% by weight to 5% by weight. Is preferable.

Hereinafter, an example of application to a dust blower as a typical spray product will be specifically described. In FIG. 2, the inside of the spray can 1 is filled with an absorber 2 for retaining liquid, and the liquefied gas G serving as a propellant is absorbed and held in the absorber 2. The metal spray can 1 is a hollow tubular body whose both ends are closed, and has a head portion H and a bottom portion B on both sides of a body portion having a constant diameter. An injection nozzle 12 having an injection port 11 opening in the center of the top surface is arranged on the head H, and has a tapered shape that expands in diameter from the top surface toward the body side. The head H is a top surface provided with an injection port 11. An injection portion 1a shown in FIG. 1 is fixed to the head H, and the valve mechanism of the injection nozzle 12 operates by pushing the injection lever 1b. As a result, when the injection nozzle 12 is opened, the vaporized gas from the liquefied gas G is injected from the injection port 1c on the head H side connected to the injection port 11.

The absorber 2 is a substantially columnar block body that follows the shape of the body of the spray can 1, and its outer diameter is equal to or slightly smaller than the inner diameter of the can. Here, the height of the absorber 2 is lower than that of the body of the spray can 1, and there is a space between the end surface of the absorber 2 on the head H side located in the body and the injection port 11 facing the head H side. Part 3 is formed. The absorber 2 is mainly composed of fiber aggregates made of crushed cellulose fibers, and the liquefied gas G is held in the voids formed between the fibers of the fiber aggregates. Preferably, the outer surface of the fiber aggregate to be the absorber 2 can be coated with the skin layer 21 made of a breathable sheet material, and in this embodiment, the entire outer surface of the fiber aggregate is the skin layer. It has a structure covered with 21.

Examples of the cellulose fiber as a raw material of the absorber 2 include cellulose fiber made of an arbitrary raw material such as bleached chemical pulp or unbleached chemical pulp of coniferous tree and hardwood, dissolved pulp, waste paper pulp, and cotton. These cellulose fibers can be pulverized by mechanically pulverizing them using a known dry or wet pulverizer, defibrator, or the like. In addition to mechanical means, chemical means, or both, can be used for pulverization. By crushing the cellulose fiber, it can be made into a fine fiber having a large surface area, and the liquid retention property is improved. In addition, synthetic fibers similar to cellulose fibers can also be used in combination.

In general, fine fibrous powder (hereinafter, appropriately referred to as paper powder) obtained by pulverizing pulp or the like contains water. For example, paper powder in a normal indoor state contains about 5 to 8% of water, and paper powder processed by a defibrator or taken out of a can has a slightly lower water content (for example,). Moisture is about 6%).

For the skin layer 21, a sheet material made of breathable paper, non-woven fabric, or the like is used so as not to interfere with the liquid absorption of the absorber 2. Further, for example, by filling a bag-shaped non-woven fabric sheet with a fiber aggregate and closing the opening, the absorber 2 whose entire outer surface is covered with the skin layer 21 can be obtained. The bag diameter is not particularly limited, but is preferably equal to or less than the inner diameter of the spray can 1. By restraining the outer surface of the fiber aggregate with the skin layer 21, the filling property and air permeability in the spray can 1 are improved, and the leakage of the liquefied gas G is suppressed even in the inverted state as shown in FIG. Highly effective.

The spray product of this embodiment holds an amount of liquefied gas G corresponding to the volume of the spray can 1 inside the absorber 2. It is considered that the liquefied gas G is held in the innumerable voids formed inside the absorber 2 by a physical force such as surface tension or van der Waals force, and is combined with the cellulose fibers constituting the absorber 2. It has a low chemical affinity. Therefore, the volume of the liquefied gas G that can be held in the absorber 2 is limited to the total volume of the voids of the absorber 2 (that is, the void volume). Further, in general, when the actual volume of the fibers and paper dust constituting the fiber aggregate is constant, the larger the volume of the absorber 2 in the spray can 1, the larger the void volume, and the liquefied gas G that can be held. The volume of is also large.

Specifically, the volume of the liquefied gas G to be filled is set to an amount exceeding 50% of the total volume of the spray can 1, and the total volume is held in the voids of the absorber 2. If the filling amount of the liquefied gas G is 50% or less of the can volume, the filling amount required for a spray product cannot be satisfied. The filling amount of general liquefied gas G varies depending on the application, but for example, most commercially available dust blowers are in the range of 53% to 59% of the can volume, and preferably 57% or more. It is good. In the application example to the torch burner, the filling amount is larger, for example, in the range of about 68% to 75% of the can volume. When the filling amount is further increased, the total volume of the absorber 2 becomes large in order to hold the liquefied gas G, and it becomes difficult to secure a sufficient space on the injection port 11 side for the vaporized gas to collect. Therefore, preferably, it is preferably about 87% of the can volume at the maximum, and it is preferable to appropriately set the amount in a range less than that so as to be a sufficient amount according to the application and the liquid retention performance of the absorber 2. ..

The volume of the space 3 formed between the absorber 2 and the injection port 11 on the head H side of the absorber 2 is 4% or more of the total volume of the spray can 1. As a result, it is possible to secure a sufficient space for the vaporized gas to collect while avoiding interference between the injection nozzle 12 (see, for example, FIGS. 1 and 2) connected to the injection port 1c and the absorber 2. Become. At this time, the volume of the absorber 2 is 96% or less of the total volume of the spray can 1, and the maximum volume of the liquefied gas G (that is, 87% of the can volume) can be retained. In general, the volume of the absorber 2 can be set to be, for example, about 80% of the can volume, that is, the volume of the space portion 3 can be set to be about 20% of the can volume.

As shown in FIG. 4, as a commonly used spray can 1, there are two types of cans C1 (for example, total volume: 590 ml) and cans C2 (for example, total volume: 660 ml) having different volumes. These cans C1 and C2 have different body volumes (for example, can C1: 550 ml, can C2: 620 ml), other can diameters (for example, actual inner diameter: 65.5 mm), and head. The volume of H (eg, 40 ml) is the same. At this time, as shown enlarged in FIG. 5, the injection port 11 has a valve structure, and the end portion of the nozzle 12 extends into the space portion 3. Therefore, the space portion 3 should be at least about 3/4 (for example, 30 ml) or more of the volume of the tapered head H, and the end portion of the nozzle 12 and the absorber 2 come into contact with each other to make the liquid Leakage can be avoided. This volume is, for example, about 5% of the total volume for the can C1 and, for example, about 4.5% of the total volume for the can C2.

Of the total volume of the spray can 1, the volume excluding the space 3 is equal to the apparent volume of the absorber 2 including the void volume, and the volume excluding the void volume from the apparent volume of the absorber 2 is the absorber 2. It is the actual volume occupied by the cellulose fibers constituting the above (that is, the following formula 1).
Equation 1: Void volume = Apparent volume of absorber 2-Actual volume of fibers constituting the absorber 2 As described above, the larger the void volume, the larger the volume of the liquefied gas G that can retain the liquid, and the voids. Since it is not possible to hold an amount of liquefied gas G that exceeds the volume, the apparent volume of the absorber 2 and the actual volume of the fiber are determined so that the void volume corresponds to the volume of the liquefied gas G required for the spray product. There is a need to.

In FIG. 4, for example, when the actual volume of the fibers constituting the absorber 2 is 70 ml and the apparent volume is equal to the volume of the body portion, the maximum amount of liquefied gas G that can be held is 480 ml for the can C1. (That is, 550 ml-70 ml; about 81% of the total volume), and for the can C2 it is 550 ml (ie, 620 ml-70 ml; about 83% of the total volume). If the apparent volume of the absorber 2 is larger and the actual volume of the fibers constituting the absorber 2 is smaller, more liquefied gas G can be retained. For example, for the can C2, when the apparent volume of the absorber 2 is the maximum (that is, 96% of the total volume) and the actual volume of the fibers constituting the absorber 2 is 60 ml (that is, 9% of the total volume). The void volume is 87% of the total volume of the spray can 1.

Here, it is desirable that the absorber 2 has a void volume equal to or larger than that of the liquefied gas G to be filled. Usually, the filling ratio of the liquefied gas G to the void volume of the absorber 2 is set to be in the range of 70% or more, preferably 74% to 100%. In general, the lower the filling ratio of the liquefied gas G, the higher the liquid retention capacity of the absorber 2, and the presence of non-retaining voids makes it difficult for the liquid to leak, but it is absorbed with respect to the volume of the liquefied gas G. Body 2 tends to grow and is inefficient. By setting the filling ratio to 70% or more, it is possible to suppress liquid leakage while efficiently retaining the required amount of liquefied gas G in the absorber 2. More preferably, it is preferable to use the absorber 2 having higher liquid retention performance so that the filling ratio of the liquefied gas G (that is, the volume of the liquefied gas G / the void volume) is 80% to 100%.

If the liquid retention performance of the absorber 2 is sufficiently high, it is sufficient that there are voids having the same volume as the required amount of the liquefied gas G, and the filling ratio is 100%. However, even if the void volume in the absorber 2 is the same, the force for holding the liquefied gas G in each void (that is, the liquid retention force) changes depending on the size of the void, the fiber type constituting the void, and the like. .. Therefore, the volume of the liquefied gas G that can be held inside the absorber 2 (that is, the saturated liquid retention volume) differs depending on the liquid retention capacity of the absorber 2. For example, the absorber 2 having many larger voids is more likely to leak than the absorber composed of innumerable fine voids. In the latter case, it is presumed that as the filling ratio increases, the liquefied gas is retained in the larger voids, and the liquid retention capacity decreases, so that the filling ratio cannot be increased to 100%.
Therefore, specifically, the filling amount of the liquefied gas G in the absorber 2 and the filling ratio with respect to the void volume are determined in consideration of the liquid holding capacity of the absorber 2. The saturated liquid retention volume will be described in detail later.

Such an absorber 2 is in a state in which the space portion 3 on the head H side and the bottom portion B side are separated from each other in the spray can 1 and the air permeability between the space portion 3 and the bottom portion B is maintained. It is stored in. Here, the air flow rate when an air pressure of 1.5 kPa is applied from the bottom B side to the head H side with the absorber 2 holding the liquefied gas G sandwiched in the spray can 1 for air permeability. Expressed as. Then, this air permeability is set so that the air flow rate converted to atmospheric pressure is 1 L / min or more. When the filling ratio of the liquefied gas G held in the absorber 2 becomes high, liquid leakage may occur due to the air permeability in the spray can 1 regardless of the liquid retention performance of the absorber 2 itself. On the other hand, a constant air pressure corresponding to a general liquid retention force is applied to one end surface side of the liquid retention absorber 2 and the flow rate passing to the other end side is measured to ventilate the spray product. It becomes possible to evaluate the sex.

The air permeability is such that the vaporized gas around the absorber 2 in the spray can 1, that is, the vaporized gas vaporized from all over the absorber 2 and emerged on the surface on the bottom B side or the outer peripheral surface is on the head H side. The state of the release path for gathering in the space 3 is shown. Therefore, the air permeability around the absorber 2 can be known by a method of using air instead of the vaporized gas generated in the spray can 1. Specifically, since the pressure at which the absorber 2 can sufficiently hold the liquefied gas G inside (that is, the liquid holding pressure) is usually about 1 kPa to 3 kPa, the value close to the lower limit is 1.5 kPa. Apply air pressure. At this time, if the flow rate of air passing to the head H side is 1 L / min or more, preferably 2 L / min or more, liquid leakage does not occur in the inverted state, and the air permeability around the absorber 2 is high. It can be judged to be good. Then, in the spray can 1, the vaporized gas on the bottom B side passes around the absorber 2 and quickly gathers in the space 3, so that the injection can be continued without liquid leakage.

The liquid retention pressure is calculated from, for example, the air pressure at which the liquefied gas G exudes from the other end surface side when air is blown from one end surface side thereof in a state where the absorber 2 is filled with a predetermined amount of liquefied gas G. can do. At this time, since the weight of the liquefied gas G is added to the obtained air pressure, when this is converted into a pressure and subtracted, the liquid holding pressure corresponding to the case of overturning is obtained. Further, instead of the liquefied gas G, a liquid held in the absorber 2 and exhibiting the same properties, such as ethanol, can be filled and the measurement can be performed at atmospheric pressure, so that the apparatus can be simplified. FIG. 6 shows the relationship between the liquid retention pressure measured using ethanol and the density of the fiber aggregates constituting the absorber 2, and the liquid retention pressure increases in proportion to the density.

On the other hand, in the spray can 1, even if the liquid retention performance of the absorber 2 is sufficiently high and the entire amount of the filled liquefied gas G is held by the absorber 2, liquid leakage occurs during inverted use. It turned out that there is. This is a case where the absorber 2 is densely filled in the spray can 1 and the air flow rate passing to the head H side is less than 1 L / min, and the discharge path is not sufficiently secured, so that the bottom B This is because the pressure of the vaporized gas generated on the side is higher than that on the H side of the head. That is, when the spray can 1 is overturned to open the injection port 11 in a state where the liquefied gas G is held at a high ratio with respect to the void volume of the absorber 2, the liquefied gas G is first generated on the side close to the space portion 3. After vaporization, vaporized gas begins to be generated from the entire absorber 2 immediately. At this time, if the flow rate of the vaporized gas passing to the head H side is small, the pressure on the bottom B side becomes higher than that on the head H side. When this pressure difference exceeds the liquid retention capacity of the absorber 2, it is presumed that the liquefied gas G inside is pushed out into the space 3 and leads to liquid leakage.

As described above, the liquid leakage at the time of inverted injection occurs when the balance between the gas pressure difference between the bottom B side and the head H side and the liquid retention force of the absorber 2 is lost. The gas pressure difference is determined by the air permeability and the outgassing flow rate, and the larger the air permeability, the smaller the gas pressure difference. Further, when the gas discharge flow rate is larger (for example, dust blower: about 50 L / min) than when the gas discharge flow rate from the injection port 11 is relatively small (for example, torch burner: about 2 to 4 L / min). , The pressure difference tends to be large. Therefore, the contribution of air permeability is large, but if the air permeability of the above lower limit value or more is secured, the pressure on the bottom B side is sufficiently reduced.

However, it is not necessary to have a higher air permeability than the expected outgassing flow rate, and preferably, the air flow rate passing to the head H side is within the upper limit of 50 L / min. Good. Even if the air permeability is increased, the effect on liquid leakage does not change so much, but rather the gap between the absorber 2 and the spray can 1 is increased so that the absorber 2 can move easily or the void volume tends to be reduced. Therefore, more preferably, the air flow rate passing to the head H side may be set to 30 L / min or less, and appropriately set so as to obtain a sufficient effect of securing the discharge path.
In applications where the outgassing flow rate is relatively small, the risk of liquid leakage is small, but safety can be further improved by setting the air permeability within the above range.

Preferably, by increasing the liquid retention capacity of the absorber 2 in addition to the air permeability of the absorber 2, even if the filling ratio of the liquefied gas G is increased, the effect of suppressing liquid leakage at the time of inverted injection is high. .. In general, the liquid retention capacity of the absorber 2 becomes better as the individual voids are fine and numerous and uniformly distributed. On the contrary, when the individual voids are large and the number is small, the surface tension and the van der Waals force are difficult to work, and the force for holding the liquefied gas G in the voids is weakened. In order to increase the holding power of the liquefied gas G under the condition that the void volume is constant, the higher the density of the absorber 2 represented by the following formula 2, the better, and the weight of the cellulose fiber mainly increases, so that the absorber 2 has a higher density. The apparent volume will also increase.
Formula 2: Density of absorber 2 = weight of absorber 2 / apparent volume of absorber 2 However, the weight of absorber 2 excludes the weight of the epidermis layer 21.

Specifically, the density of the absorbent body 2, may be in the range of ^{0.12g / cm 3 ~0.22g / cm 3} . When the density is 0.12 g / cm ³ (for example, the liquid retention pressure is about 1 kPa from FIG. 6) or more, the number of fine voids that hold the liquefied gas G increases with respect to the normal filling amount of the liquefied gas G. , Surface tension and van der Waals force become easier to work. However, there is a limit to the increase in the volume of the absorber 2 in the spray can 1 having a constant volume, and when the density is increased, the void volume decreases by the amount that the actual volume of the fibers constituting the absorber 2 increases. Therefore, normally, the density is set in the range of 0.22 g / cm ³ (for example, the liquid retention pressure of about 3 kPa from FIG. 6) or less so that a void volume capable of filling a predetermined amount of liquefied gas G can be obtained. Good. Preferably, the density of the absorber 2 is in the range of 0.13 g / cm ^{3 to} 0.21 g / cm ³ (for example, the liquid retention pressure is about 1.2 kPa to 2.7 kPa according to FIG. 6), and the liquid retention is high. Force is obtained and the void volume can be made sufficiently large.

Further, as an index for measuring the liquid retention capacity of the absorber 2, the saturated floor area ratio (unit:%) represented by the following formula 3 can be used.
Equation 3: Saturated volume ratio = (saturated liquid retention volume / void volume) x 100
Here, the saturated liquid retention volume is the maximum volume of the liquefied gas G that can be filled in the absorber 2, and the liquefied gas G is filled and increased while the absorber 2 is housed in the spray can 1. It can be calculated from the weight and specific gravity. Similar to the above-mentioned measurement of the liquid retention pressure, an equivalent liquid such as ethanol can be used instead of the liquefied gas G.

The saturated volume ratio is determined by the void volume of the absorber 2 and the general liquid retention capacity. The higher the liquid retention capacity of the absorber 2, the larger the saturated liquid retention volume, and the more liquefied gas G can be filled with respect to the void volume. If the liquid holding power is sufficiently strong, the saturated liquid holding volume and the void volume become almost equal, and the saturated volume ratio becomes close to 100%. Preferably, the saturated floor area ratio is 80% or more, more preferably 90% to 100%. If the liquefied gas G is filled in excess of the saturated floor area ratio, the liquefied gas G will leak out in the spray can 1. Therefore, the saturated floor area ratio is calculated in advance, and the above-mentioned liquefied gas is within the range. It is better to select the filling ratio of G.

Further, as a factor that affects the liquid retention capacity of the absorber 2, the bulkiness of the fiber aggregate constituting the absorber 2 can be mentioned. The absorber 2 is required to have a structural strength for maintaining the apparent volume of the absorber 2 while holding the liquefied gas G inside, and in order to maintain the structural strength, the fiber aggregate constituting the absorber 2 is required. A certain amount of is required. However, if the amount of fiber aggregate is too large, the void volume in the apparent volume decreases. In order to maintain the structural strength that maintains the apparent volume without increasing the amount of fiber aggregates, it is necessary to adjust the bulkiness, which is determined by the amount of cellulose-based fibers and the length, thickness, elasticity, etc. of the fibers. It is desirable that it is effective and has an appropriate bulk.

The bulkiness of the fiber aggregate to be the absorber 2 can be quantified by filling a cylindrical body equivalent to the spray can 1 with the fiber aggregate and measuring the bulkiness after repeated pressurization. In this measurement method, a certain amount of fiber aggregate (for example, 50.0 g) is filled in a non-woven fabric bag to be the skin layer 21 and placed in a cylindrical body (for example, inner diameter 63 mm) corresponding to the spray can 1. , A piston (for example, a weight of 1.0 to 1.1 kg) is naturally dropped onto the absorber 2. This may be repeated (for example, dropped 10 times from a height of about 5 cm from the upper part of the absorber 2), and the height of the absorber 2 may be measured in a pressurized state on which the piston is placed.
In this measuring method, the performance as the absorber 2 can be more appropriately judged than the initial bulkiness by a general bulkiness test. The absorber 2 may be an unused product or may be measured by kneading the one taken out from the spray can 1 after use.

When the bulkiness of the fiber aggregate is large, the restoring force of the absorber 2 becomes high, and it becomes easy to secure a desired void volume. On the other hand, the fact that the bulkiness of the fiber aggregate is large means that if the fibers are of the same quality, the fiber length becomes long, the number of fibers decreases, and the number of fine voids and the number of fibers decreases slightly, so that the liquid retention capacity is slightly low. It is presumed to be. Therefore, in order to increase the liquid retention capacity, the upper limit of the bulkiness of the fiber aggregate is preferably 150 mm or less. Further, when the bulkiness is reduced, the liquid retention capacity is increased, but the weight of the fiber aggregate for obtaining a desired void volume is increased. Therefore, the lower limit of the bulkiness of the fiber aggregate is preferably 110 mm or more. Preferably, the bulkiness is in the range of 120 mm to 140 mm.

The bulkiness of the fiber aggregate varies depending on the fiber raw material and the fiber length, and can be appropriately selected so that the absorber 2 has a desired structural strength and liquid retention capacity. In order to keep the bulkiness of the fiber aggregate in a desired range, a plurality of cellulose fibers having different degrees of defibration and fiber types may be combined. For example, mixed paper powder obtained by mixing bleached kraft pulp (that is, BKP) defibrated paper powder with BKP fine powder obtained by further refining this defibrated paper powder, or BKP fine powder mixed with defibrated paper powder of used newspaper. Mixed paper powder can be used.

Further, the absorber 2 can also be formed by adding a powder additive for adjusting the bulk to the fiber aggregate composed of these defibrated paper powder and mixed paper powder. Examples of such powder additives include various fillers such as calcium carbonate, talc, white clay, and calcium carbonate, and powders such as starches, fine fibrous cellulose, and diatomaceous soil, which are mixed and used with bulky cellulose fibers. Therefore, the bulkiness can be reduced.

The amount of the powder additive for adjusting the bulkiness is preferably about 0 to 30% with respect to the weight of the fiber aggregate, and more preferably in the range of 0 to 25%. Starches and fine fibrous celluloses are suitable because they can be used as edible or food additives and do not adversely affect the working environment during handling. Since calcium carbonate has an effect of raising pH, it has an effect of preventing rust from being generated in the spray can 1 when the absorber 2 contains water.

The method for accumulating fibers for forming the fiber aggregate is not particularly limited, and the crushed cellulose fibers may be directly filled in the spray can 1 or the fiber aggregate having a shape corresponding to the spray can 1 in advance. As a result, the spray can 1 may be filled. The fiber aggregate may be, for example, a block-shaped molded body compressed in the vertical direction or the horizontal direction (that is, the axial direction or the radial direction of the spray can 1) using a known compression molding machine, and further, the skin layer 21. It may be covered with a non-woven fabric sheet or stored in a non-woven fabric bag to form the absorber 2.

(Embodiment 2)
As shown in FIGS. 7 and 8, cellulose fibers may be deposited on a non-woven fabric sheet to be the skin layer 21 to form a sheet material having a predetermined thickness, which may be wound into a columnar shape to form an absorber 2. .. A thicker sheet material folded in half may be arranged into a columnar shape to form the absorber 2. Further, a heat-sealing fiber or a binder may be added to the cellulose fiber, and the molded shape can be easily maintained. In this way, with respect to the absorber 2 whose entire surface is not covered with the skin layer 21, a lid-shaped filter member 4 having air permeability can be arranged between the absorber 2 and the space portion 3.

The filter member 4 is made of, for example, a disk-shaped porous body having a constant thickness formed to have a diameter slightly larger than the inner diameter of the spray can 1. Preferably, a non-woven fabric sheet, which is a breathable fiber aggregate, can be used and laminated to a predetermined thickness to form the filter member 4. As the fibers constituting the non-woven fabric, any of synthetic fibers, natural fibers, inorganic fibers, regenerated fibers and the like can be preferably used. As a result, even if the surface of the absorber 2 facing the space 3 is not covered with the skin layer 21, the surface is protected so as to be breathable, the displacement of the absorber 2 and the scattering of fibers are regulated, and the liquid is liquid. The leak prevention effect can be enhanced.

At this time, the same effect can be obtained by setting the air permeability within the above range. Further, in order to adjust the air permeability, a ventilation member 5 may be provided on the outer periphery of the absorber 2. The ventilation member 5 is arranged in the spray can 1 in contact with at least a part of the outer peripheral surface of the absorber 2, and forms a ventilation path in the axial direction and the radial direction of the spray can 1. This ventilation path serves as a release path for vaporized gas at the time of injection, and reduces the pressure difference between the bottom B side and the head H side of the absorber 2 to prevent liquid leakage. The ventilation member 5 is made of, for example, a strip-shaped microflute corrugated cardboard plate having a large number of small holes penetrated in the thickness direction or a thick non-woven fabric sheet, and is evenly arranged at a plurality of locations on the outer periphery of the absorber 2. ..

When the absorber 2 is filled, if it is brought into close contact with the inner wall surface of the spray can 1, the displacement of the absorber 2 is suppressed, but if the bulk density of the fiber aggregate is large, the stress inside the can of the absorber 2 (that is, that is, The repulsive force) becomes large, and the air permeability tends to decrease. In particular, if the filling ratio of the liquefied gas G into the absorber 2 is large, there is a high possibility that liquid leakage will occur. In such a case, by appropriately arranging the ventilation member 5, the desired ventilation can be obtained. Obtainable. Alternatively, if the outer diameter of the absorber 2 is equal to the inner diameter of the spray can 1 and the cross-sectional shape thereof is a slightly flat circular shape, the absorber 2 is brought into close contact with the inner wall surface of the spray can 1 to improve air permeability. be able to. The flatness of the absorber 2 is, for example, 0.12 or less, preferably 0.10 or less.

As in the first embodiment, in the configuration in which the entire surface of the absorber 2 is covered with the skin layer 21, the ventilation member 5 may be arranged on the outer periphery. Further, of course, the lid-like member 4 may be interposed between the space portion 3 and the space portion 3.

(Example 1)
A spray product in which various absorbers 2 and liquefied gas G were filled in a spray can 1 was prepared by the method shown below, and the air permeability was evaluated. The liquefied gas G is a mixed liquefied gas in which 5% by weight or less of carbon dioxide gas is mixed with DME, and 350 ml of the liquefied gas G is filled after inserting the absorber 2 into the spray can 1 to form a spray product for a dust blower. did.
As shown in Table 1, two types of absorbers 2 having adjusted bulkiness were used. As the raw material cellulose fiber, bleached kraft pulp (that is, BKP) defibrated paper powder and used newspaper defibrated paper powder are used, and BKP defibrated paper powder / BKP fine powder ≈ 8/2 mixed paper powder ( That is, a fiber aggregate composed of BKP-based; bulky 125 mm) and mixed paper powder of newspaper waste paper krafted paper powder / BKP fine powder ≈7/3 (that is, waste paper-based; bulky 132 mm) was prepared.

For each of these two types of fiber aggregates, the weights of the cellulose fibers were changed to 70 g, 85 g, and 93 g, and the spray can 1 having an inner diameter of 65.5 mm (for example, can C1 or can C2 in FIG. 4) was designated. It was inserted and filled so as to have the insertion depth of. The absorber 2 is obtained by directly filling the spray can 1 without molding (that is, samples 1 and 2), and further, whether or not the skin layer 21 of the absorber 2 is formed, whether or not compression molding is performed, and a molding method. Was prepared and used as Sample 3 to Sample 15. The insertion depth is set so that the height of the absorber 2 inserted from the bottom B side of the spray can 1 is 25 mm or 45 mm from the bottom B, the bottom lid is wrapped, and then the absorber is pushed from the can mouth with a rod. 2 was brought into close contact with the bottom of the can.

The bulkiness of the fiber aggregate to be the absorber 2 was measured based on the following measuring method.
(Bulk measurement method)
50.0 g of the fiber aggregate is pushed into a non-woven fabric bag having a diameter of 66 to 70 mm (for example, PP / PE composite fiber, 20 g / m ² , gusseted, depth 245 mm) to be the skin layer 21, and sealed. Let it be absorber 2. A transparent plastic cylinder having an inner diameter of 63 mm and a height of about 230 mm, which is substantially equivalent to the spray can 1, is erected on a table, and the absorber 2 is inserted to prepare so that a large gap is not formed at the bottom. A cylindrical piston (for example, weight 1.0 to 1.1 kg, diameter 60 mm, height about 260 mm) is inserted into the cylindrical body and naturally dropped from a height of about 5 cm above the absorber 2. Is repeated 10 times. The height of the absorber 2 (that is, the height from the top surface of the table to the bottom surface of the piston) is measured in mm units in a state of pressurization on which the piston is placed. After the measurement, the absorber 2 is taken out, kneaded, inserted again, and the same is performed. This is repeated 5 times in total, and the center value (unit: mm) is defined as the “bulk” of the fiber aggregate.

Specifically, the absorber 2 is formed by filling a long pipe smaller than the inner diameter of the spray can 1 with mixed paper powder as a fiber aggregate and compressing it in the axial direction to a length that can be inserted into the spray can 1 in advance. As a body, a spray can 1 is directly filled (that is, vertical compression; samples 3 and 4), and ventilation members 5 made of strip-shaped microflute corrugated cardboard are placed at three locations on the inner wall of the spray can 1 at equal intervals. After arranging in, the absorbers 2 of the samples 3 and 4 were inserted and integrated (that is, the samples 5 and 6) were prepared.
The microflute corrugated cardboard plate serving as the ventilation member 5 has a thickness of 2.5 mm, a width of 20 mm, and a height of 168 mm, and has a plurality of hollow portions parallel in the height direction and a large number of through holes in the plate thickness direction. Breathability is provided in the axial direction and the radial direction of the spray can 1.

Further, after the disk-shaped filter member 4 is pushed into the shoulder portion (that is, the boundary portion between the body portion and the head portion H) of the spray can 1, the absorber 2 in which the paper dust mat is wound in a columnar shape is inserted ( That is, the sample 7) and the ventilation member 5 made of a non-woven fabric sheet are arranged at three positions on the inner wall of the spray can 1 at equal intervals, and then the absorber 2 of the sample 7 is inserted and integrated (sample 7). That is, sample 8) was prepared.
The paper dust mat is obtained by thickly depositing mixed paper powder on a breathable sheet to be the skin layer 21 and appropriately compressing it, and winding the paper dust mat so that the skin layer 21 is the outermost surface between layers. A columnar absorber 2 having no gap was used. As the breathable sheet, a 20 g / m ² non-woven fabric sheet made of PE / PP composite fiber is used, and the non-woven fabric sheet to be the ventilation member 5 is a strip shape having a width of 15 mm and a height of 170 mm by laminating the above-mentioned breathable sheets. Was used.

Further, a breathable bag to be the skin layer 21 is filled with mixed paper powder after being appropriately compressed to form an absorber 2 (that is, samples 9 and 10), and the breathable bag is filled with the above. Samples 3 and 4 were filled with the vertically compressed mixed paper powder to form the absorber 2 (that is, samples 11 and 12), and further filled with the vertically compressed mixed paper powder to form the absorber 2. (That is, samples 13 and 14) and mixed paper powder formed into a rectangular shape were filled into the absorber 2 (that is, sample 15).

The breathable bag is a bag-shaped non-woven fabric sheet made of PE / PP composite fiber (that is, 20 g / m ² , thickness about 0.1 mm, bag diameter 66 mm, depth 245 mm, weight 1.4 g). , Gazette processing), and after filling with paper dust, the opening was closed to obtain an absorber 2 covered with a skin layer 21. In the case of the one mainly composed of horizontal compression, first, in a mold shorter than the length of the spray can 1, the mixed paper powder is horizontally compressed and molded to be thinner than the inner diameter of the can, and then extruded into a pipe thinner than the inner diameter of the can and appropriately vertically compressed. Placed in the above breathable bag. In the case of the one mainly composed of vertical compression, first, in a mold sufficiently longer than the length of the spray can 1, the mixed paper dust is laterally compressed to be thinner than the inner diameter of the can, and then extruded into a pipe thinner than the inner diameter of the can to be vertically compressed and molded. Placed in a breathable bag. For the rectangular parallelepiped shape, the mixed paper powder was placed in the above-mentioned breathable bag, horizontally compressed with a mold having a rectangular cross section and one side smaller than the inner diameter of the can, and then vertically compressed.

Samples 1 to 15 were blow-tested by the following method to examine the effect of the spray product on liquid leakage during inverted use. The spray can 1 of each sample was equipped with a valve at which the injection flow rate when only the vaporized gas was released was about 50 L / min at atmospheric pressure. Prior to the blow test, the spray can 1 filled with the liquefied gas G was left for 1 day and then kept in a chamber at 25 ° C. for 3 hours. Immediately after the spray can 1 was inverted, the injection port 11 was opened, gas blowing was started, and blowing was continued for 30 seconds. During this period, if the injected gas was not mixed with the liquid, it was judged as good: ○, and if it was mixed with the liquid, it was judged as not possible: ×. The results are shown in Table 1.

In addition, after the blow test, as shown below, a breathability test was conducted using a breathability measuring device to investigate the relationship between the breathability of each sample and liquid leakage.
(Breathability test)
The air permeability measuring instrument is configured by connecting an intake of compressed air and an air supply pipeline provided with an air flow rate control device to a metal tubular container for sending air into the spray can 1. In the metal tubular container, the upper end surface of a silicon rubber plate having an outer diameter of 90 mm with a hole of φ15 mm is horizontally stretched to serve as a mounting surface for the spray can 1, and the spray can is sprayed so as to be in close contact with the bottom B of the spray can 1. A device for fixing the can 1 is attached. In the air supply pipeline, a low-pressure air regulator, a low-flow mass flow meter, and a low-pressure air pressure sensor are arranged in this order between the intake and the metal tubular container to form an air flow control device. Compressed air can be supplied so that the air pressure becomes a predetermined value.

In the spray product, a hole was made in the head H side of the spray can 1 in which the absorber 2 was housed, all the liquefied gas G inside was blown, and the spray product was left for 1 day or more. After that, the head H was excised in order to eliminate air resistance, two holes having a diameter of 5 mm to 8 mm were made in the bottom B, and the head H was set in a breathability measuring instrument and brought into close contact with a silicon rubber plate to be a mounting surface. At this time, in order to make it possible to measure the air permeability of the absorber 2 in a liquid-retaining state at atmospheric pressure, 350 ml of ethanol was filled as a liquid equivalent to DME instead of the liquefied gas G.
A compressed air pipe was connected to the intake of the air permeability measuring instrument, and the pressure was adjusted using a low pressure air regulator so that the pressure detected by the low pressure air pressure sensor became a predetermined flow rate determination pressure. Further, the air flow rate measured by the low flow rate mass flow meter at that time was defined as the air flow rate passing from the bottom B side to the head H side via the absorber 2, that is, air permeability. The results are also shown in Table 1.

The flow rate determination pressure was set to 1.5 kPa, which is near the pressure actually generated in the can and is near the liquid retention pressure of the absorber 2. In order to know the liquid retention pressure, prior to the air permeability test, the bottom B of the spray can 1 after the total blow was cut and the resistance in the can of the absorber 2 was measured. By converting this into gas pressure, it was found that in most cases where liquid leakage occurred, the pressure was in the range of 1.5 to 3.5 kPa, and the lower limit was adopted as the flow rate determination pressure.

Before the air permeability test, the axial length of the absorber 2 was measured and the void volume was calculated from the apparent volume. As a result, all the absorbers 2 having an insertion depth of 25 mm had a void volume of 420 ml or more. Those with 470 ml and an insertion depth of 45 mm had void volumes in the range of 400 ml to 420 ml (ie, filling ratios of 74% to 87.5%). Further, in all of the absorber 2, and the density was in the range of ^{0.14g / cm 3 ~0.17g / cm 3} .

From the results in Table 1, no liquid leakage occurred in the sample having a breathability of 1.0 L / min or more regardless of the amount of mixed paper dust as the absorber 2, the molding method, and the presence or absence of the skin layer 21. In addition, the smaller the bulkiness of the fiber aggregate with the same amount of mixed paper dust, and the smaller the amount of mixed paper powder with the same bulkiness, the higher the air permeability tends to be, and the former tends to improve the liquid retention capacity. In addition, the latter is presumed to affect the increase in void volume.

Further, the air permeability is improved by molding in advance, and the effect of the vertically compressed samples 11 and 12 is higher than that of the horizontally compressed samples 13 and 14. Further, the air permeability is improved by providing the skin layer 21 and the ventilation member 5, and the samples 9 to 15 using the breathable bag serving as the skin layer 21 are more breathable than the samples 1 to 4 not used. Samples 5, 6 and 8 which are high and have the ventilation member 5 arranged have higher ventilation than the samples 3, 4 and 7 which are not used. As described above, the desired air permeability can be realized by appropriately combining the amount of mixed paper dust, the molding method, the bulkiness of the fiber aggregate, and the presence or absence of the skin layer 21.

(Example 2)
For samples 5, 6, 8 to 15 of Example 1, as the liquefied gas G, 400 ml of a mixed liquefied gas of propane and butane (propane / butane ≈ 4/6) was used instead of the mixed liquefied gas of DME / carbon dioxide gas. It was filled to make a spray product for torch burners. Blow tests for torch burners were performed on these samples to investigate their effect on liquid leakage during inverted use of spray products. The spray can 1 of each sample was equipped with a burner having an injection flow rate of about 3 L / min at atmospheric pressure when only vaporized gas was released.

Prior to the blow test, the spray can 1 filled with the liquefied gas G was left for 1 day and then kept in a chamber at 35 ° C. for 3 hours. A burner was attached to the spray can 1, and immediately after ignition, the spray can 1 was inverted and the combustion state was observed for 60 seconds. If there was no abnormal combustion, it was judged as good: ○, and if there was a risk of liquid leakage or abnormal combustion, combustion was stopped and it was judged as impossible: ×. The results are shown in Table 2. In addition, the air permeability test was performed in the same manner as in Example 1, and the results are also shown in Table 2.

No abnormal combustion was observed in any of the samples 5, 6, 8 to 15. Moreover, the air permeability was sufficiently larger than 1 L / min, and good results were obtained. From Examples 1 and 2, if the spray can 1 has a predetermined air permeability, the liquid leaks even if the liquefied gas G is held at a high filling ratio with respect to the void volume of the absorber 2. It can be seen that safety can be ensured without any problems.

(Example 3)
Similar to the sample 14 of Example 1, a spray product having a structure in which a breathable bag to be the skin layer 21 is vertically compressed and then filled with waste paper-based mixed paper powder to form an absorber 2 is provided as an absorber 2. The apparent volume of the paper was kept substantially constant, and the density was changed to investigate the relationship with the liquid retention capacity. Newspaper waste paper defibrated paper powder / BKP fine powder ≒ 8/2 mixed paper powder (that is, bulkiness 140 mm) was used in the range of 40 g to 130 g to form a fiber aggregate, but the same method was used for dust blowers. A spray product was made.

The obtained spray product was filled with 350 ml of DME / carbon dioxide gas ≈99 / 1 as liquefied gas G, and the same blow test was performed. At this time, if only the vaporized gas was injected in the inverted state, the injection was immediately stopped. When the liquids were mixed and jetted, the injection was stopped with the end point when the liquids completely stopped coming out. The spray can 1 was weighed and converted into a volume, and the residual volume of the liquefied gas G and the injection volume of the liquefied gas G were calculated. Next, after the liquefied gas was completely released, the head H of the spray can 1 was cut off, the length of the absorber 2 was measured, and the outer diameter of the absorber was set to 63 mm, and the apparent volume was calculated. Further, the void volume was calculated by subtracting the actual volume of the mixed paper dust used from the apparent volume. The results are shown in FIG.

As is clear from FIG. 8, when the apparent volume of the absorber 2 is made substantially constant (for example, about 450 ml to 500 ml) and the amount of mixed paper dust is increased, as the density of the absorber 2 increases. The void volume gradually decreases, but the residual volume of the liquefied gas increases and gradually decreases after reaching a peak. When the density exceeds 0.1 g / cm ³ , the ratio of the residual volume to the void volume rapidly increases, the injection volume of the liquefied gas G becomes 0, and liquid leakage does not occur. The residual volume of the liquefied gas G gradually decreases when the density exceeds 0.17 g / cm ³ , and almost converges to more than 300 ml at around 0.22 g / cm ³ .

The residual volume of the liquefied gas G corresponds to the volume that can be held by the absorber 2, that is, the saturated liquid holding volume, and can hold more than 50% of the liquefied gas G with respect to the total volume of 590 ml of the spray can 1 without leakage. Understand. Also, the larger the void volume to the apparent volume, the hold without leaking the liquid with higher liquid gas G is preferably a density in the range of 0.12g / cm ³ ~0.22g / cm ³ You can see that.

(Example 4)
Similar to Samples 12 to 13 of Example 1, a spray product obtained by compressing and then filling a breathable bag to be the skin layer 21 with BKP-based or waste paper-based mixed paper powder to form an absorber 2 The effect on the void volume and air permeability was investigated by changing the amount, composition, bulkiness, etc. of the mixed paper powder. Tables 3 to 6 show the various conditions of the samples 16 to 22, and the results of the blow test and the air permeability test.
Further, following the air permeability test, the saturated liquid retention volume is measured by the test method shown below, and the ratio to the void volume, that is, the saturated volume ratio represented by the above formula 3 is also shown in Tables 3 to 6. did. At this time, as in the air permeability test, the ethanol saturated liquid holding volume at atmospheric pressure was calculated instead of the liquefied gas G.

(Saturated liquid retention volume test method)
In the spray product, a hole was made in the head H side of the spray can 1 in which the absorber 2 was housed, all the liquefied gas G inside was blown, and the spray product was left for 1 day or more. Then, the head H was excised, two holes having a diameter of 5 mm to 8 mm were made in the bottom B, and the solution was retained until ethanol was saturated as a liquid equivalent to DME instead of the liquefied gas G. Specifically, the spray can 1 was inverted, ethanol was poured from the bottom of the can until the liquid leaked, the spray can 1 was upright, ethanol was poured in the same manner, and the mixture was left for 3 hours so as not to dry. Then, the spray can 1 was turned upside down and left for about 20 minutes until the excess liquid did not drip, and weighed. The saturated liquid retention volume was obtained from the weight and specific gravity of the retained ethanol obtained by subtracting the weight of the spray can 1 before retaining the ethanol from the weight of the spray can 1 in the saturated ethanol state.

Further, in order to know the stress in the can of the absorber 2 in the spray can 1, the repulsive force of the absorber 2 was measured by the method shown below, and they are also shown in Tables 3 to 6. In addition, the diameter and flatness of the absorber 2 in the spray can 1 were measured and shown in the table.
(Repulsive force test method)
In the spray product, after blowing all the liquefied gas G inside, the bottom B of the spray can 1 was cut off to take out the absorber 2. A flat plate material having a width of 20 mm is brought into contact with the side surface of the absorber 2 so as to cross the radial direction and pushed downward so that the major axis is about 91% of the inner diameter of the spray can 1 (for example, when the inner diameter of the can is 65.5 mm). The force required to compress until 60.0 mm) was measured on an electronic balance.

As the sample 16, 50 g to 115 g of BKP paper powder having a bulkiness of 127 mm was used, and the sample 16 was vertically compressed in the same manner as the sample 11 and then filled in a breathable bag to obtain an absorber 2. Density of the absorbent body 2 is in the range of ^{0.115g / cm 3 ~0.221g / cm 3} , with the increase of density, void volume, and a saturated liquid retention volume is increasing. In particular, in a sample having a density of the absorber 2 of 0.12 g / cm ³ or more, a desired amount of liquefied gas having a saturated volume ratio of more than 90% and a filling ratio of about 80% to 85% with respect to a void volume of 400 ml or more. G can be held with high liquid retention power. When the density of the absorber 2 is lower than 0.12 g / cm ³ , the liquid retention capacity is slightly reduced, but by filling the liquefied gas G within the saturated liquid retention volume, the required amount of the liquefied gas G is added. Can be retained.

However, as the density of the absorber 2 becomes higher, the air permeability tends to decrease, and in the sample having a density of 0.221 g / cm ³ and an air permeability of 0.6 L / min, even if the saturated liquid holding volume is sufficiently large, the blow is blown. Leakage was observed in the test. No liquid leakage occurred in the sample having a breathability of 1 L / min or more.

For sample 17, 85 g of mixed paper powder obtained by mixing BKP fine powder with BKP paper powder so that the bulkiness of the fiber aggregate is in the range of 85 mm to 154 mm is used, and the sample 17 is vertically compressed and then ventilated in the same manner as the sample 11. It was filled in a sex bag to obtain absorber 2. As the bulkiness increases, the apparent volume and the void volume of the absorber 2 increase. In particular, those having a bulkiness of 115 mm to 146 mm have a void volume of 400 ml or more and a saturation volume ratio of 94%. The above and high liquid retention capacity are shown. When the bulkiness is as low as 85 mm, the void volume becomes as small as 340 ml due to the decrease in apparent volume, but since the density is high and the saturated volume ratio is also high, the required amount of liquefied gas is reduced by reducing the filling ratio to the void volume. G can be retained.

However, as the bulk increases, the air permeability tends to decrease, and in a sample with a bulk height of 154 mm and an air permeability of 0.5 L / min, liquid leakage is observed in the blow test even if the saturated liquid retention volume is sufficiently large. Was done. No liquid leakage occurred in the sample having a breathability of 2 L / min or more.

For sample 18, 60 g to 70 g of mixed paper powder obtained by mixing BKP fine powder with BKP paper powder so that the bulkiness of the fiber aggregate is in the range of 110 mm to 150 mm is used, and the sample 18 is vertically compressed in the same manner as the sample 11. Was filled into a breathable bag to form absorber 2. Using bulkiness is moderately high fiber aggregate, the density of the absorbent body 2, when such a relatively low range and ^{0.122g / cm 3 ~0.138g / cm 3} , the void volume of 422ml~438ml The saturated volume ratio is 84% to 94%, showing a high liquid retention capacity. The air permeability was also good at 1.5 L / min or more, and no liquid leakage occurred in any of the samples.

For sample 19, 85 g to 95 g of mixed paper powder obtained by mixing BKP fine powder with used newspaper paper powder so that the bulkiness of the fiber aggregate is 134 mm is used, and the sample 19 is laterally compressed in the same manner as the sample 14 and then breathable. Was filled in the bag to prepare the absorber 2. When the density of the absorber 2 is set to a relatively high range of 0.177 g / cm ^{3 to} 0.205 g / cm ³ by using a fiber aggregate having a moderately high bulk, the void volume is 319 ml to 412 ml. It gets a little smaller. Therefore, the saturated floor area ratio is as high as 99%, and the filling ratio can be sufficiently increased as 84% or more.

However, when the filling ratio is as large as 80% or more, the liquid retention capacity may decrease due to deformation when the absorber 2 is inserted into the spray can 1 or repulsive force in the can. Therefore, in the sample with a slightly large flatness of 0.12, the repulsive force is slightly reduced to 1.6 kg to suppress the interference with the spray can 1 at the time of insertion, and in the sample with a slightly large repulsive force of 3.1 kg. , The flatness is slightly reduced to 0.09. When both the flatness and the repulsive force are not increased in this way, good liquid retention and air permeability are maintained, and liquid leakage does not occur.

In sample 20, a mixed powder obtained by mixing 93 g of BKP paper powder having a high bulk of 146 mm with a powder additive for adjusting the bulk is laterally compressed in the same manner as in sample 13, and then filled in a breathable bag. , Absorber 2. As the powder additive, A to D shown below were used, and the powder was formulated so that the bulkiness was in the range of 115 mm to 122 mm. The content of the powder additive B in the mixed powder was 30% by weight, and the other powder additives A, C, and D were 25% by weight.
A: Undenatured corn starch; manufactured by Oji Cornstarch Co., Ltd., average particle diameter of about 15 μm, bulkiness of 30 mm
B: Acetic acid ester-modified tapioca starch; manufactured by Matsutani Chemical Co., Ltd., average particle diameter of about 15 μm, bulkiness of 29 mm
C: Industrial talc powder; manufactured by Nippon Tarku Co., Ltd., average particle diameter of about 12 μm, bulk height of 25 mm
D: Light calcium carbonate; manufactured by Okutama Kogyo Co., Ltd., average particle diameter of about 1 μm, bulkiness of 28 mm
E: Heavy calcium carbonate; manufactured by Maruo Calcium Co., Ltd., average particle diameter 1.8 μm, bulk height 20 mm

In the sample in which the bulky and large amount of BKP paper powder was used alone, the air permeability became as small as 0.6 L / min, and liquid leakage occurred. Further, in the molding method mainly composed of lateral compression, the flatness tends to be as large as 0.12, the amount of paper dust is large, and the repulsive force is as large as 3.1 kg. On the other hand, in the samples to which the powder additives A to D were added, the bulkiness was reduced to 115 mm to 122 mm, and the saturated floor area ratio and the filling ratio of the liquefied gas G were high. In addition, the air permeability was increased to 2.0 L / min or more, and no liquid leakage occurred.

For sample 21, 70 g of mixed paper powder obtained by mixing BKP fine powder with used newspaper paper powder so that the bulkiness of the fiber aggregate is 134 mm is used, and the bag is laterally compressed in the same manner as sample 14 and then is a breathable bag. Was filled into the absorber 2 to obtain the absorber 2. The absorber 2 was filled in a spray can 1 having a total volume of 590 ml so that the density was 0.148 g / cm ³ . For sample 22, 70 g to 100 g of mixed paper powder obtained by mixing BKP fine powder with used newspaper paper powder so that the bulkiness of the fiber aggregate is 127 mm is used, and as in sample 14, the same vertical and horizontal compression is performed and then aeration is performed. It was filled in a sex bag to form an absorber 2. The absorber 2 was filled in a spray can 1 having a total volume of 660 ml so that the density was 0.125 g / cm ^{3 to} 0.169 g / cm ³ .
As the liquefied gas G, a mixed liquefied gas of propane and butane is used instead of the mixed liquefied gas of DME and carbon dioxide gas. The spray can 1 having a total volume of 590 ml has 400 ml of the mixed liquefied gas, and the spray can 1 has 660 ml. It was filled with 440 ml of mixed liquefied gas to prepare a spray product for torch burners.

In each of the spray products, the saturation volume ratio was as high as 90% or more, the air permeability was 1.0 L / min or more, and no liquid leakage occurred.

The present invention is not limited to the above embodiments, and can be applied to various embodiments without departing from the gist thereof. For example, the liquefied gas used in the dust blower is not limited to a flammable liquefied gas such as DME or LPG, and a flammable gas other than these can also be used in the torch burner. Of course, it can also be used for purposes other than dust blowers and torch burners.

1 Spray can 11 Injection port 2 Absorber 21 Skin layer 3 Space 4 Filter member G Liquefied gas H Head B Bottom

Claims (9)

A spray can having an injection port on the head side, an absorber for liquefied gas and liquid retention filled in the spray can, and a space formed between the absorber and the injection port to collect vaporized gas. It is a spray product equipped with
The absorber is mainly composed of fiber aggregates made of crushed cellulose fibers, and voids in which the liquefied gas is held are formed between the fibers of the fiber aggregates.
The cellulose fiber contains at least one of wood pulp and waste paper pulp.
The volume of the liquefied gas exceeds 50% of the total volume of the spray can, and the total amount is held in the voids of the fiber aggregate.
The volume of the space portion is 4% or more of the total volume of the spray can.
In the spray can, the air permeability indicating the state of the air passage between the head side and the bottom side separated by the absorbent body in the liquid retention state is adjusted from the bottom side to the inside of the spray can. Using an air permeability measuring instrument including an air supply pipeline capable of supplying compressed compressed air and a flow meter arranged in the air supply pipeline, the absorber is used from the bottom side to the head side. A spray product represented by the air flow rate measured by the flow meter when an air pressure of 1.5 kPa is applied toward the spray product, the air permeability of which is 1 L / min or more in terms of atmospheric pressure. The spray product according to claim 1, wherein the air permeability is 2 L / min or more and 50 L / min or less. The density of the absorbent body is ^{0.12g / cm 3 ~0.22g / cm 3} , the spray product according to claim 1 or 2. The spray product according to any one of claims 1 to 3, wherein the absorber has a volume of the liquefied gas held in the voids of 70% to 100% of the total volume of the voids. The absorber has a saturated liquid holding volume which is the maximum amount of the liquefied gas that can be held in the voids, which is 80% to 100% of the total volume of the voids, according to any one of claims 1 to 4. Described spray products. The spray product according to any one of claims 1 to 5, wherein the outer surface of the absorber is covered with a breathable epidermis layer. The spray product according to any one of claims 1 to 6, wherein a filter member having air permeability is interposed between the absorber and the space portion. Any of claims 1 to 7, wherein in the spray can, a ventilation member that forms a ventilation path in the axial direction and the radial direction of the spray can is arranged in close contact with at least a part of the outer peripheral surface of the absorber. The spray product according to item 1. The spray product according to any one of claims 1 to 8, wherein the absorber contains a powder additive for adjusting the bulkiness.

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