JP2008013603A - Manufacturing method of moisture-permeable tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a moisture-permeable tube that can sharply decrease a granular structure or breakage thereby enhancing the non-defective ratio as well as the material yield resulting in reduction in the production cost. <P>SOLUTION: The manufacturing method of the moisture-permeable tube comprises a pellet production process where a moisture-permeable polyurethane is pulverized into a flaky form to give a flake material and the flake material is pelletized to give a pellet and a tube-manufacturing process where the pellet is molded into a tube-like form to give a tube-like molded article, and the tube-manufacturing process is carried out at a temperature out of the recrystallization temperature range. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing a moisture-permeable tube made of moisture-permeable polyurethane.

As a method for producing a moisture permeable tube made of moisture permeable polyurethane, for example, the one disclosed in Patent Document 1 is known.
JP 2003-246832 A

  However, in the method of manufacturing a moisture-permeable tube disclosed in the above-mentioned patent document, the rate of defective products (for example, an abnormal thick part (hereinafter referred to as “scratch”) of 1.5 mm or more and a high tear rate) is high. In addition, the material yield (total weight of the moisture-permeable tube determined to be non-defective product / total weight of the moisture-permeable polyurethane used) is lowered, resulting in an increase in manufacturing cost.

  The present invention has been made in view of the above-mentioned circumstances, and can reduce dripping and tearing. The yield rate (number of moisture permeable tubes determined to be non-defective products / total number of moisture permeable tubes produced) can be reduced. Moisture permeability that can improve the material yield (total weight of moisture-permeable tube determined to be non-defective product / total weight of moisture-permeable polyurethane used) and reduce manufacturing costs. It aims at providing the manufacturing method of a tube.

The present invention employs the following means in order to solve the above problems.
The manufacturing method of the moisture-permeable tube by this invention pulverizes moisture-permeable polyurethane into flake shape, manufactures flake material, pelletizes the said flake material, and the pellet manufacturing process which manufactures a pellet, The said pellet in tube shape And a tube manufacturing process for manufacturing a tube-shaped formed body, wherein the tube manufacturing process is performed at a temperature outside the recrystallization temperature region.
According to such a method of manufacturing a moisture permeable tube, it is possible to reduce the occurrence of a crystalline substance inside the moisture permeable polyurethane in the tube manufacturing process, and therefore, it is possible to reduce irregularities and tears. The yield rate can be improved, the material yield can be improved, and the manufacturing cost can be reduced.
The recrystallization temperature region may be a temperature region that excludes the vicinity of the temperature peak at which recrystallization occurs in the moisture-permeable polyurethane.

In the manufacturing method of the said moisture-permeable tube, the said pellet manufacturing process was made to perform at the temperature which removed the recrystallization temperature range.
According to such a method of manufacturing a moisture permeable tube, it is possible to reduce the occurrence of a crystalline substance in the moisture permeable polyurethane in the pellet manufacturing process, and thus it is possible to reduce scumming and tearing. The yield rate can be improved, the material yield can be improved, and the manufacturing cost can be reduced.

In the manufacturing method of the moisture permeable tube, the temperature excluding the recrystallization temperature region is 190 ° C. or higher and 194 ° C. or lower, 196 ° C. or higher, preferably 197 ° C. or higher, more preferably 205 ° C. or higher.
According to such a method of manufacturing a moisture permeable tube, it is possible to prevent the occurrence of a crystalline substance inside the moisture permeable polyurethane, so that it is possible to greatly reduce the flaws and tears, The rate can be improved, the material yield can be improved, and the manufacturing cost can be reduced.
In this case, the recrystallization temperature region is around 195 ° C.

A method for producing a moisture-permeable tube according to the present invention includes a tube production step of producing a flake material by pulverizing moisture-permeable polyurethane into a flake shape, forming the flake material into a tube shape, and producing a tube-shaped formed body. In the manufacturing method of a moisture-permeable tube provided, the tube manufacturing process is performed at a temperature excluding the recrystallization temperature region.
According to such a method of manufacturing a moisture permeable tube, it is possible to reduce the occurrence of a crystalline substance inside the moisture permeable polyurethane in the tube manufacturing process, and therefore, it is possible to reduce irregularities and tears. The yield rate can be improved, the material yield can be improved, and the manufacturing cost can be reduced.
The recrystallization temperature region may be a temperature region that excludes the vicinity of the temperature peak at which recrystallization occurs in the moisture-permeable polyurethane.

In the manufacturing method of the moisture permeable tube, the temperature excluding the recrystallization temperature region is 190 ° C. or higher and 204 ° C. or lower or 206 ° C. or higher, preferably 190 ° C. or higher and 200 ° C. or lower, or 210 ° C. or higher, more preferably 215. It is above ℃.
According to such a method of manufacturing a moisture permeable tube, it is possible to prevent the occurrence of a crystalline substance inside the moisture permeable polyurethane, so that it is possible to greatly reduce the flaws and tears, The rate can be improved, the material yield can be improved, and the manufacturing cost can be reduced.
In this case, the recrystallization temperature region is around 205 ° C.

The moisture-permeable tube according to the present invention comprises a moisture-permeable polyurethane obtained by reacting an isocyanate component, a polyol as a chain extender, and polyethylene glycol as a polyol component as at least raw materials. It is a wet tube, Comprising: The heat history of the said moisture-permeable polyurethane is comprised so that it may have the temperature area | region which removed the recrystallization area | region.
According to such a moisture-permeable tube, it is possible to reduce the occurrence of a crystalline substance inside the moisture-permeable polyurethane, so that it is possible to reduce scumming and tearing and improve the yield rate. In addition, the material yield can be improved and the manufacturing cost can be reduced.

  According to the method of manufacturing a moisture-permeable tube according to the present invention, it is possible to greatly reduce the flaws and tears, improve the yield rate, improve the material yield, and reduce the manufacturing cost. There is an effect that can be.

Hereinafter, an embodiment of a method for producing a moisture-permeable tube according to the present invention will be described with reference to the drawings.
First, a moisture-permeable polyurethane obtained by polymerizing an isocyanate component, a specific chain extender, and a polyol component as main raw materials and by reacting these main raw materials so that each has an appropriate blending ratio is used as flakes. To make a flake material.

  The isocyanate component is not particularly limited and various conventional ones are used. For example, 4,4′-methylenebisphenyl isocyanate (MDI), hexamethylene diisocyanate, toluene diisocyanate, 4,4′-cyclohexylmethane diisocyanate, isophorone isocyanate, etc. are used. (MDI) is suitably used because of its low vapor pressure and excellent handling and workability, and the mechanical properties of the resulting polyurethane are also high.

  As the chain extender, 1,4-butanediol is used. Conventionally, for example, in a moisture-permeable polyurethane resin for clothing, ethylene glycol was used as a chain extender. In this case, polymerization and molding in a solvent were performed in this manner. By using 4-butanediol, the solvent is eliminated as described later. As the chain extender used as a raw material for polyurethane, various other materials such as diethylene glycol, triethylene glycol, 1,5-pentanediol and 1,6-hexanediol can be used. From the viewpoint of securing moldability and mechanical properties of the resulting polyurethane, 1,4-butanediol can be particularly preferably used.

  As the polyol component, polyethylene glycol (PEG) having a molecular weight of 600 or more and 4000 or less is used. This is because polyethylene glycol has better moisture permeability of the resulting polyurethane resin than, for example, a copolymer of polytetramethylene glycol (PTMG) or polypropylene glycol (PPG) and polyethylene glycol. Also, the molecular weight, that is, the weight average molecular weight is 600 or more and 4000 or less, when it exceeds 4000, the reactivity becomes low, and when it is less than 600, the reactivity becomes high and the polymerization of the stable polymer is reversed. This is because it becomes difficult and the moisture permeability becomes low and may become impractical. In addition, the molecular weight is preferably in the range of 2500 to 3000, and by making such a range, it is possible to ensure stable polymerizability of the polymer and good moisture permeability of the obtained polyurethane. Can do.

  As this polyol component, a silicon-type polyol can be used in addition to the polyethylene glycol. As this silicon-type polyol, the polysiloxane carbinol modified body shown below is used in particular, and among these, those having a molecular weight of 100 or more and 3000 or less are preferably used.

  This silicon-type polyol is added in a small amount in order to impart the characteristic that the obtained polyurethane has a small intermolecular force (cohesive force) of silicon. Silicon-type polyol is used to increase the mold release property during molding, particularly tube molding, and to reduce the tackiness of the molding. The blending amount of such silicon-type polyol with respect to the entire polyol component is 1 wt% or more and 70 wt% or less, preferably 2 wt% or more and 4 wt% or less. If it is less than 1 wt%, the silicon content in the resulting polyurethane will be small, so that the effect of increasing the mold release property and reducing the tackiness cannot be obtained sufficiently, and if it exceeds 70 wt%, an expensive silicon polyol is added. This is because the physical properties such as moldability and mechanical strength obtained are saturated. Moreover, in the range of 2 wt% or more and 4 wt% or less, the releasability at the time of tube forming can be increased, the tackiness of the molded product can be reduced, and sufficient moisture permeability can be obtained.

  Further, the blending amount of the chain extender and the polyol component is preferably such that the ratio is within a range of 3 mol or more and 10 mol or less, more preferably 4 mol or more with respect to 1 mol of the polyol component. It is prepared and used within a range of 10 mol or less. If the chain extender is less than 3 moles with respect to 1 mole of the polyol component, the strength of the resulting polyurethane will be insufficient and the practicality will be reduced. If it exceeds 10 moles, the moisture permeability of the resulting polyurethane will be reduced. This is because the polymerization of the polymer becomes difficult. Moreover, when it exceeds 4 mol, the strength of the resulting polyurethane is good, which is preferable.

  Further, the blending amount of the isocyanate component and the polyol component is preferably within a range in which the ratio of the isocyanate component is 4 mol or more and 12 mol or less, more preferably 5 mol or more and 10 mol or less with respect to 1 mol of the polyol component. It is prepared and used. By setting it as such a range, while being able to ensure favorable polymer polymerizability, the favorable intensity | strength of the polyurethane obtained can be ensured.

  Further, the moisture-permeable polyurethane of the present invention preferably contains an antibacterial agent. That is, in the moisture-permeable polyurethane of the present invention, in addition to the main raw material consisting of the isocyanate component, the chain extender, and the polyol component, the antibacterial agent preferably exceeds 0.1% by weight and is 1.0% by weight. In the following, it is added and blended more preferably in the range of 0.2 wt% to 1.0 wt%, desirably 0.5 wt% to 1.0 wt%. The antibacterial agent to be added is generally a powder or granule which is also called an antifungal agent or an antibacterial / antifungal agent, and is not particularly limited and is known, ie, an inorganic one (for example, Silver-based antibacterial agents) and organic materials (for example, iodine-based antibacterial agents; 3-iodo-2-propylbutylcarbamate), and inorganic / organic composite materials (for example, iodine-based composite antibacterial agents) are used. Of these three systems, an inorganic / organic composite system is particularly preferable. This is because inorganic materials have low activity and high durability, while organic materials have high activity and poor durability. This is because it is preferable to use a composite antibacterial agent in order to make good use of the characteristics.

  In addition, the content (addition amount) of the antibacterial agent is preferably 0.1% by weight or more and 1.0% by weight or less, more preferably 0.2% by weight or more and 1.0% by weight or less, desirably 0. The range of 5% by weight or more and 1.0% by weight or less is that the antibacterial (antifungal) effect due to the addition is not sufficiently observed at 0.1% by weight or less from the experimental results described later. This is because the effect is saturated even if it exceeds wt%, and the antibacterial agent is more expensive than the main raw material, which is disadvantageous in terms of cost. Further, the effect becomes more remarkable when the content is 0.2% by weight or more and 1.0% by weight or less, and when the content is further 0.5% by weight or more and 1.0% by weight or less, the effect is saturated. This is because a better effect can be obtained.

  The moisture-permeable polyurethane is formed by reacting the isocyanate component, the chain extender and the polyol component as main raw materials, and then adding the antibacterial agent as necessary. In the reaction of the main raw material, known urethanization catalysts, stabilizers, compatibilizers, colorants and the like can be appropriately added.

  As described above, moisture-permeable polyurethane uses a solvent by using an isocyanate component, a specific chain extender, and a polyol component as main raw materials, and reacting these main raw materials so that each has an appropriate blending ratio. It is obtained by polymerizing without. The reaction method is not particularly limited, and a known method such as a prepolymer method or a one-shot method can be employed. Further, when the antibacterial agent is contained, for example, a method of adding and mixing the antibacterial agent to the obtained reaction product after reacting the main raw material is employed.

  The moisture-permeable polyurethane obtained in this manner has good high moisture permeability and mechanical properties by itself, particularly when it is composed of main raw materials, and further has good moldability. Pelletization by the granulation method is possible. Moreover, at the time of such pelletization, that is, at the time of granulation, the antibacterial agent (antifungal agent) is added to a granulator, and the antibacterial agent is kneaded into pellets obtained by melt mixing. it can. Similarly, various additives such as various extenders such as talc, silica and calcium carbonate, conductive agents such as carbon, and catalysts and enzymes can be incorporated. The temperature at the time of such pelletization (at the time of granulation) is about 200 ° C., for example. Furthermore, by using the pellets thus obtained, various molding methods such as an extrusion molding method can be used.

Next, using the 1st extruder 11 as shown in FIG. 1, the said flake material is pelletized (granulated) and a pellet is manufactured.
The first extrusion molding machine 11 heats and melts a hopper 12 containing a flake material (moisture permeable polyurethane pulverized into flakes) as a material and the flake material (moisture permeable polyurethane) supplied from the hopper 12. A molding machine main body 14 that pushes it out with a screw 13, and an adapter 15 and a die 16 provided at the tip of the molding machine main body 14 are provided.
A die plate having a plurality of through holes (not shown) is attached to the tip of the die 16. In addition, a breaker including a motor (not shown) and a rotary blade attached to the tip of a rotary shaft rotated by the motor is provided near the through hole of the die plate. The pelletized moisture-permeable polyurethane (pellet) flows downstream along with the cooling water supplied near the breaker, and is guided to a centrifugal dehydrator (not shown).
The temperature conditions in the first extruder 11, that is, the temperatures of C1, C2, C3, adapter 15, and die 16 in FIG. 1 are as follows.
C1: 200 ° C, C2: 200 ° C, C3: 190 ° C,
Adapter 15: 190 ° C, Die 16: 210 ° C

  Here, when the flake material and the pellet are compared, the flake material does not have a heat history, whereas the pellet has a heat history as described above. In addition, the shape of the flake material is indefinite, whereas the shape of the pellet is substantially definite (for example, a grain size of rice grains). Further, the melt viscosity of the flake material is 6000 to 20000 Pa.s. s / 210 ° C., whereas the pallet has a melt viscosity of 1000 to 3000 Pa.s. s / 200 ° C. Furthermore, when the moisture permeation performance of the pellet is 100, the humidification performance of the flake material is about 80.

Subsequently, the pellet is formed into a tube shape by using a second extruder 21 as shown in FIG.
The second extrusion molding machine 21 is a molding machine that extrudes a hopper 22 containing pellets (pelletized moisture-permeable polyurethane) as a material and a screw 23 while heating and melting the pellets supplied from the hopper 22. A main body 24 and a die gate 25 and a die 26 provided at the tip of the molding machine main body 24 are provided.

The die 26 has a core 27 as shown in FIG. 6 and a flow path 28 through which moisture-permeable polyurethane passes. That is, the moisture-permeable polyurethane that passes through the flow path 28 is gradually expanded in diameter from the point where it reaches the tip (upstream end) of the core 27, and then moved while keeping the same diameter for a while. The diameter is gradually reduced toward the end.
The exit end of the die 26 is formed in a circular shape having a desired diameter, and an air nozzle (not shown) is provided at the center of the die gate 25 or the inside of the die 26. Based on such a configuration, the second extrusion molding machine 21 melts the supplied pellets and extrudes them to the front end side of the molding machine main body 24 with the screw 23, and further from the air nozzle to the center of the molding. By ejecting air and extruding from the die 26 while making a hole in the center thereof, a tube-shaped molded body (for example, an outer diameter of 4.5 mm, an inner diameter of 4.0 mm, a thickness of 0.25 mm, and a length of 135 mm) Tube). In addition, as the pelletized moisture-permeable polyurethane used as a material, the above-mentioned antibacterial agent may or may not be contained.

Here, when the flake material is pelletized and when the pelletized pellet is formed into a tube shape, the present inventors perform these treatments under conditions of a predetermined temperature or higher, thereby reducing The knowledge that tearing can be reduced significantly was obtained.
First, the flake material is heated and cooled according to a heat cycle as shown in FIG. That is, it is once heated to a predetermined temperature (for example, 200 ° C.), held at that temperature for a predetermined time (for example, 30 minutes), cooled, and reheated.
Then, the melting peak temperature and the endothermic amount upon reheating are measured. Then, for example, a graph as shown in FIG. 5 can be obtained. In FIG. 5, the horizontal axis represents temperature (° C.), and the vertical axis represents the amount of heat (mW) applied (applied) to the heating wire for heating the die 26. In FIG. 5, the predetermined time is 60 minutes.
Next, the same test is repeated by changing the predetermined temperature, and these measurement results are summarized in FIG. In FIG. 4, the horizontal axis represents the predetermined temperature (° C.), and the vertical axis represents the melting peak temperature (° C.) and the endothermic amount (J / g) upon reheating.

  FIG. 4 shows that when the predetermined temperature reaches 215 ° C. or higher, the melting peak temperature disappears and the endothermic amount becomes 0 (zero). In other words, this means that if the flake material is treated under conditions of 215 ° C. or higher, recrystallization does not occur inside, and no crystalline substance (high melting point substance) exists inside. Yes.

Next, the pellets produced by the first extruder 11 are heated and cooled according to a heat cycle as shown in FIG. That is, it is once heated to a predetermined temperature (for example, 200 ° C.), held at that temperature for a predetermined time (for example, 30 minutes), cooled, and reheated.
Then, the melting peak temperature and the endothermic amount upon reheating are measured. Then, for example, a graph as shown in FIG. 5 can be obtained. In FIG. 5, the horizontal axis represents temperature (° C.), and the vertical axis represents the amount of heat (mW) applied (applied) to the heating wire for heating the die 26. In FIG. 5, the predetermined time is 60 minutes.
Next, the same test is repeated by changing the predetermined temperature, and these measurement results are summarized in FIG. In FIG. 4, the horizontal axis represents the predetermined temperature (° C.), and the vertical axis represents the melting peak temperature (° C.) and the endothermic amount (J / g) upon reheating.

  FIG. 4 shows that when the predetermined temperature is 205 ° C. or higher, the melting peak temperature disappears and the endothermic amount becomes 0 (zero). In other words, this means that if the pellet is treated at a temperature of 205 ° C. or higher, recrystallization does not occur inside, and no crystalline substance (high melting point substance) exists in the inside. .

  Accordingly, when pelletizing the flake material in the first extruder 11, it is processed at a temperature of 215 ° C. or higher, and when the pelletized pellet in the second extruder 21 is formed into a tube shape, 205. By performing the treatment at a temperature equal to or higher than ° C., it is possible to prevent the generation of a crystalline substance inside the moisture-permeable polyurethane.

According to the method of manufacturing a moisture-permeable tube according to the present embodiment, it is possible to prevent a crystalline substance from being generated inside the moisture-permeable polyurethane, and therefore an abnormally thick part (also referred to as “pox”). And tearing can be greatly reduced, and the yield rate (number of moisture-permeable tubes determined to be non-defective / total number of moisture-permeable tubes produced) can be improved, and material yield (permeability determined to be non-defective) can be improved. The total weight of the wet tube / the total weight of the moisture-permeable polyurethane used) can be improved, and the manufacturing cost can be reduced.
In addition, the “non-defective product” referred to here is a product having no defects.

Another embodiment of the method for producing a moisture-permeable tube according to the present invention will be described.
The manufacturing method of the moisture permeable tube which concerns on this embodiment is the point which is made to supply the said flake material directly to the hopper 22 of the 2nd extrusion molding machine 21, without using the 1st extrusion molding machine 11. This is different from the above-described embodiment.

  In the present embodiment, since the flake material is supplied to the second extruder 11, when the flake material is formed into a tube shape in the second extruder 21, the temperature is 215 ° C. or higher. Will be processed.

  Since the operational effects are the same as those of the above-described embodiment, the description thereof is omitted here.

The present invention is not limited to the above-described embodiment. For example, in the case where the size of the material is smaller than 1 mm and there is no tail, the flake material is pelletized. The temperature at which the flake material is formed into a tube shape can be 210 ° C. or higher or 190 ° C. to 200 ° C. The temperature at which the pelletized pellet is formed into a tube shape is 197 ° C. Thus, temperature management can be made more gradual.
FIG. 6 shows a specific example in which the temperature when the pelletized pellet is formed into a tube shape is set to 197 ° C. or higher. As shown in FIG. 6, in this specific example, the temperature outside the flow path 28 in the die 26 is maintained at approximately 200 ° C., and the temperature inside the flow path 28 is maintained at 204 ° C. or higher. In the vicinity of the core 27, the temperature inside the flow path 28 becomes higher than the temperature outside, because a heating wire (not shown) for heating the die 26 is wound around the outside of the die 26, This is because the core 27 is configured to easily collect heat.

In addition, for example, in the case where the size of the fluff is 1 mm or less and the presence or absence of the tailing cannot be determined or the one with the tailing is a non-defective product, when the flake material is pelletized, or The temperature at which the flake material is formed into a tube shape can be, for example, 206 ° C. or higher, or 190 ° C. to 204 ° C. (that is, a temperature region that avoids the vicinity of 205 ° C.). The temperature at the time of forming into a tube shape can be set to 190 ° C. to 194 ° C. or 196 ° C. or higher (that is, a temperature range avoiding the vicinity of 195 ° C.), and temperature management can be made more gradual. it can.
The melting point of moisture-permeable polyurethane is 190 ° C.

It is a figure for demonstrating the manufacturing method of the moisture-permeable tube by this invention, Comprising: It is a sectional side view of a 1st extrusion molding machine. It is a figure for demonstrating the manufacturing method of the moisture-permeable tube by this invention, Comprising: It is a sectional side view of a 2nd extrusion molding machine. It is a figure for demonstrating the test conditions of the test done in order to acquire the knowledge of this invention. It is the graph which put together the result of the test done in order to acquire the knowledge of this invention. It is a graph which shows one test result of the test done in order to acquire the knowledge of the present invention. It is a figure which shows one specific example of the manufacturing method of the moisture-permeable tube by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 1st extrusion molding machine 12 Hopper 13 Screw 14 Molding machine main body 15 Adapter 16 Die 21 1st extrusion molding machine 22 Hopper 23 Screw 24 Molding machine main body 25 Digate 26 Die 27 Core 28 Flow path

Claims (6)

A flake material is manufactured by pulverizing moisture-permeable polyurethane into flakes,
Pelletizing the flake material to produce pellets; and
The pellet is formed into a tube shape, and a tube manufacturing process for manufacturing a tube-shaped formed body, and a moisture-permeable tube manufacturing method comprising:
A method for manufacturing a moisture-permeable tube, wherein the tube manufacturing step is performed at a temperature outside the recrystallization temperature region.   The method for manufacturing a moisture-permeable tube according to claim 1, wherein the pellet manufacturing step is performed at a temperature excluding the recrystallization temperature region.   The temperature excluding the recrystallization temperature region is 190 ° C or higher and 194 ° C or lower or 196 ° C or higher, preferably 197 ° C or higher, more preferably 205 ° C or higher. The manufacturing method of the moisture-permeable tube as described in 1 .. A flake material is manufactured by pulverizing moisture-permeable polyurethane into flakes,
The flake material is formed into a tube shape, and a tube manufacturing process for manufacturing a tube-shaped formed body, and a moisture-permeable tube manufacturing method comprising:
A method for manufacturing a moisture-permeable tube, wherein the tube manufacturing step is performed at a temperature outside the recrystallization temperature region.   The temperature excluding the recrystallization temperature region is 190 ° C. or higher and 204 ° C. or lower or 206 ° C. or higher, preferably 190 ° C. or higher and 200 ° C. or lower or 210 ° C. or higher, more preferably 215 ° C. or higher. The manufacturing method of the moisture-permeable tube of Claim 4. A moisture permeable tube comprising a moisture permeable polyurethane obtained by reacting an isocyanate component, a polyol as a chain extender, and polyethylene glycol as a polyol component at least as raw materials, and reacting these raw materials,
The moisture-permeable tube, wherein the heat history of the moisture-permeable polyurethane has a temperature region excluding the recrystallization region.

Images