JP2006281654A - Molding die and manufacturing method for seamless molded product using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture, without causing breakage and efficiently, seamless molded products such as gloves formed of a polyurethane resin. <P>SOLUTION: The molding die 10 is the one having a molding face 11 and a non-molding face 12 formed on the outer surface and the one for manufacturing the seamless molded product comprising a polyurethane resin porous film by attaching to the molding face 11 a solution containing a water-coagulative polyurethane resin and by coagulating with a coagulant, and the molding die 10 is formed of a porous material equipped with through-holes which penetrate the molding face 11 and the non-molding face 12. By charging a fluid into the through-holes from the non-molding face 12 and discharging the fluid from the molding face 11 the seamless molded product can easily be peeled off from the molding face 11, which is efficient. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a mold for manufacturing a seamless molded product such as a medical glove, and a method for manufacturing a seamless molded product using the mold.

In medical practice, work in a clean room, sports, outdoor leisure, etc., there are cases where specific gloves, socks, etc. are worn due to hygiene and workability. As such, for example, Patent Document 1 describes seamless molded articles such as gloves, mittens, and socks formed from a layered composite material having at least a polyurethane layer and a hydrophilic non-porous polymer layer. When producing such a seamless molded product, a non-porous mold is used, and a hydrophilic polymer dry film and a polyurethane layer are sequentially formed on the mold, and then formed into a mold. A method is used in which water is inserted between the molded product and the molded product is peeled off from the mold.
JP 09-512760 gazette

  However, in the method described in Patent Document 1, when the molded product is peeled off from the molding die, it takes time and the water pressure is locally applied to a part of the molded product, so that the molded product is damaged. There was also a risk that it was not efficient.

  This invention is made | formed in view of the said situation, and makes it a subject to provide the shaping | molding die and manufacturing method for manufacturing efficiently seamless molded articles, such as gloves which consist of polyurethane resins, without damaging.

  As a result of intensive studies, the present inventors have found that by using a specific mold, a seamless molded product such as a glove can be efficiently manufactured without being damaged, and the present invention has been completed.

The molding die of the present invention has a molding surface and a non-molding surface, which is a part other than the molding surface, formed on the outer surface, and a solution containing a water-solidifying polyurethane resin is adhered to the molding surface. A molding die for producing a seamless molded article made of a polyurethane resin porous film by coagulating a resin with a coagulating liquid, the porous mold having a through-hole penetrating the molding surface and the non-molding surface It is made of a material.
The porous material is preferably one selected from the group consisting of unglazed, ceramics, resins, and metals.
The method for producing a seamless molded product according to the present invention includes a molding surface and a non-molding surface, which is a portion other than the molding surface, formed on the outer surface, and includes a through-hole penetrating the molding surface and the non-molding surface. An adhesion step of adhering a solution containing a water-coagulable polyurethane resin to the molding surface of a mold made of a porous material, and coagulation for coagulating the polyurethane resin with a coagulating liquid to form a polyurethane resin porous film And a peeling step of peeling the seamless molded product made of the polyurethane resin porous film from the molding surface by flowing a fluid from the non-molding surface into the through-hole and allowing the fluid to flow out of the molding surface. It is characterized by having.

  According to the present invention, a seamless molded product such as a glove made of polyurethane resin can be efficiently produced without being damaged.

Hereinafter, the present invention will be described in detail.
[Molding mold]
FIG. 1 is a perspective view showing an example of a mold 10 according to the present invention for manufacturing a glove as a seamless molded product.
The mold 10 includes a molded surface 11 having an outer shape that is formed on a part of the outer surface along the glove, and a non-molded surface 12 that is a portion other than the molded surface 11 on the outer surface. After a solution containing a coagulable polyurethane resin (hereinafter referred to as a polyurethane resin liquid) is adhered, the polyurethane resin is solidified by bringing it into contact with a coagulating liquid, thereby solidifying the polyurethane resin having a shape along the molding surface 11. It is for manufacturing gloves made of membrane. In the illustrated example, the molding surface 11 is below the two-dot chain point, and the non-molding surface 12 is above.
Further, the mold 10 is formed of a porous material having a large number of through holes penetrating the molding surface 11 and the non-molding surface 12. Therefore, as will be described in detail later, a liquid is injected from the non-molding surface 12 into the through-hole, and the liquid is caused to flow out of the molding surface 11, thereby forming the liquid surface on the molding surface 11. The formed seamless molded product can be easily peeled off from the molding surface 11 without being damaged. Further, as will be described in detail later, it is possible to increase the efficiency of solidification of the polyurethane resin by allowing the coagulating liquid to flow from the non-molded surface 12 into the through hole.

Further, in the molding die 10 of FIG. 1, a concave liquid inlet 13 is formed in a part of the non-molding surface 12 so that the liquid can easily flow from the non-molding surface 12 into the through hole. Is poured into the through hole communicating with the liquid inlet 13.
The mold 10 in the example of FIG. 1 uses a liquid such as water as an inflow / outflow fluid. Therefore, the liquid injection port 13 is formed, but it is not necessarily formed as described later. It does not have to be. Moreover, gas, such as air and nitrogen, can also be used as a fluid. In that case, the gas injection means is configured by connecting at least a part of the non-molding surface 12 and a pump for press-fitting gas into the through hole with a pipe, and the seamless molding formed on the molding surface 11 is performed. The product may be made peelable by atmospheric pressure.

The porous material forming the mold 10 is preferably a material having a large number of through holes and capable of forming the mold 10 having through holes penetrating the molding surface 11 and the non-molding surface 12. If it is, there will be no restriction | limiting in particular, However, 1 type chosen from the group which consists of unglazed, ceramics, resin, and a metal can be used preferably. More preferably, those having a porosity of 50 to 70% and an average pore diameter of 50 to 300 μm are preferable. When the porosity and the hole diameter are such, the seamless molded product can be easily peeled while further preventing the breakage, and the stripping does not take a long time and does not affect the shape of the seamless molded product. In the present specification, the porosity is expressed as the area ratio of the pores per unit area when the surface of the mold 10 is observed with an electron microscope. Similarly, the average pore diameter is a value obtained by calculating the long diameter (maximum length) of each hole on the surface and averaging the obtained diameters.
In addition, as long as there are preferably a large number of through holes penetrating the molding surface 11 and the non-molding surface 12, the molding die 10 penetrates the molding surfaces 11 or the non-molding surfaces 12 in addition to such through holes. There may be through-holes that are present or non-through-holes may be present.

  The unglazed ceramics and ceramics are, for example, unglazed ceramics and porous ceramics used in flower pots. These are not vitrified with a glaze or the like, and when exposed to liquid, the liquid gradually infiltrates into the through hole and then flows out. Therefore, although it is suitable as a material of the mold 10, these tend to be easily broken or chipped by an impact such as dropping. Therefore, from the viewpoint of handleability and the like, the porous material is preferably made of resin or metal.

As a suitable method for forming a porous material made of resin or metal, continuous pores in which pores are connected by appropriately fusing only the vicinity of the surface layer of the resin powder or metal powder and leaving a void inside. There is a so-called sintering method for producing a body. By manufacturing the molding die 10 from such a continuous porous body, the molding die 10 having a through-hole penetrating the molding surface 11 and the non-molding surface 12 can be manufactured. Examples of the metal include stainless steel and aluminum.
Furthermore, since it is easy to manufacture the mold 10 and is resistant to impact and easy to handle, resins such as polyethylene, polypropylene, polymethyl methacrylate, polystyrene, ethylene vinyl acetate polymer, and tetrafluoroethylene polymer are preferably used. In addition, polypropylene and tetrafluoroethylene polymers are preferred from the viewpoints of hardness, heat resistance, chemical resistance, and the like.

[Seamless molded product manufacturing method]
Next, the case where a glove is manufactured using the shaping | molding die 10 of FIG. 1 is illustrated, and the suitable manufacturing method of a seamless molded product is demonstrated in detail.
When manufacturing a glove using the mold 10 of FIG. 1, first, an adhesion process is performed in which a water-coagulable polyurethane resin liquid is adhered to the molding surface 11 of the mold 10.

A specific method of attaching the polyurethane resin liquid is not limited as long as the resin liquid adheres to the molding surface 11, and a method of spraying the polyurethane resin liquid from the nozzle and spraying the molding surface 11; Although the method etc. which apply | coat to the molding surface 11 with a brush etc. are mentioned, since it is excellent in workability | operativity and it is easy to make it adhere with a uniform film thickness, as shown in FIG. A method of immersing the mold 10 is preferable.
Here, the immersion time is preferably 1 to 60 minutes from the viewpoint of easy formation of a more uniform film thickness and work efficiency.

The polyurethane resin liquid used here contains at least a water-solidifying polyurethane resin and a solvent for dissolving the polyurethane resin.
The polyurethane resin is not particularly limited as long as it is water-coagulable, and an ether type or a polyester type can be used as appropriate. However, since the polyester type polyurethane resin has an ester bond, it extends more than the ether type polyurethane resin. Property, stretch recovery, and tear strength. Accordingly, a polyester-based polyurethane resin is preferably used.
As the solvent, a water-soluble polar organic solvent such as dimethylformamide, dimethylacetamide, or N-methylpyrrolidone is preferably selected from the solubility of the polyurethane resin and the coagulation property and desolvation property in the coagulation step performed after the adhesion step. The

  The ratio of the polyurethane resin and the solvent in the polyurethane resin liquid is preferably in the range of 50 to 600 parts by mass of the solvent with respect to 100 parts by mass of the polyurethane resin. Here, when the solvent is less than 50 parts by mass, the adhesiveness of the polyurethane resin liquid to the mold 10 becomes excessive, and it may be difficult to peel the seamless molded product from the mold 10 in the peeling process described later. On the other hand, when it exceeds 600 mass parts, formation of a polyurethane resin porous membrane becomes difficult, and a desired seamless molded product may not be obtained. Further, the viscosity of the polyurethane resin liquid is preferably 100 to 5000 mPa · s. When a material having such a viscosity is used, the strength of the obtained seamless molded product is excellent, and the handleability of the liquid itself is also good.

In addition, as a water-coagulable polyurethane resin liquid, those having a solid content of 30% by mass are commercially available and may be used.
In addition, the polyurethane resin liquid may contain a known antibacterial agent (for example, a pyrithione zinc complex, an inorganic metal (silver, zinc, copper, etc.) zeolite, or an inorganic metal (silver, zinc, copper, etc.) ceramic. Etc.), cell regulators (anionic surfactants, hydrophobic nonionic surfactants, etc.), crosslinking agents (polyisocyanates in which 3 moles of diisocyanate are added to 1 mole of trimethylolpropane, or trimers of diisocyanate). ) Can be added. Furthermore, in order to improve the designability, a pigment or the like may be added.

Next, a so-called wet coagulation step is performed in which the molding die 10 to which the polyurethane resin liquid is adhered is brought into contact with the coagulation liquid to coagulate the polyurethane resin and form a polyurethane resin porous film.
According to such a coagulation step, the polyurethane resin coagulates and the solvent in the polyurethane resin liquid is removed, so that the polyurethane resin becomes a porous film. As a result, a three-dimensional seamless molded product made of a polyurethane resin porous film along the molding surface 10 is formed on the molding surface 11. In addition, according to such a coagulation process, the polyurethane resin coagulates in a short time due to contact with the coagulation liquid, so that a cocoon-like coagulated product that is inferior in quality is formed without particularly troublesome work. A seamless molded product having a uniform film thickness is obtained without being formed on the product.

Here, the coagulation liquid is not particularly limited as long as it does not dissolve the polyurethane resin and dissolves the solvent in the polyurethane resin liquid, and examples thereof include a dilute aqueous solution of a solvent contained in the polyurethane resin liquid in addition to water. Water is preferable from the viewpoints of handling, environment and the like.
The coagulation temperature (liquid temperature of the coagulation liquid) is usually 5 to 80 ° C., but 5 to 40 ° C. is preferable because the pore diameter of the polyurethane resin porous membrane tends to be in an appropriate range such as 1 to 100 μm. When the pore diameter of the polyurethane resin porous membrane is in such a range, it has moisture permeability for escaping water vapor such as evaporated sweat to the outside, stretch recovery is 80% or more, and has excellent shape compatibility and sufficient durability. Easy to manufacture seamless molded products.
Here, the recovery from expansion and contraction is an arrangement of JIS L 1096 8.14.3, after 4 cycles of 1 cycle of stretching for 3 minutes (200% expansion) and then returning to the original for 1 minute. The recovery rate after extending again for 3 minutes in the same manner (width 50 mm, grip 50 mm).

A specific method for bringing the mold 10 to which the polyurethane resin liquid is adhered into contact with the coagulating liquid is not particularly limited, but it is excellent in workability, can be coagulated in a shorter time, and has a uniform film thickness. Since it is easy to form a porous resin membrane, as shown in FIG. 3, the molding die 10 so that the polyurethane resin liquid adhering to the molding surface 11 is immersed in a container containing the coagulating liquid, that is, the coagulating bath 30. The method of immersing is preferable.
Furthermore, as shown in FIG. 4, a method of immersing the entire mold 10 so that the non-molded surface 12 of the mold 10 to which the polyurethane resin liquid adheres is also immersed in the coagulation bath 30 is also preferable. According to such a method, since the coagulation liquid is injected from the non-molding surface 12, the polyurethane resin can be coagulated not only from the outside but also from the inside, and the coagulation process can be made efficient.
The immersion time is preferably 1 to 60 minutes from the viewpoint of easy formation of a more uniform film thickness and work efficiency.

After such a coagulation step, the polyurethane resin porous formed on the molding surface 11 by injecting the liquid from the non-molding surface 12 of the molding die 10 into the through-hole and letting it flow out of the molding surface 11. For the seamless molded product made of the material film, a peeling step is performed to release the seamless molded product from the molding surface 11 by applying a force that moves away from the molding surface 11.
Here, the liquid to be injected from the non-molded surface 12 (hereinafter referred to as “peeling liquid”) is not particularly limited as long as it does not dissolve the polyurethane resin, and is contained in the polyurethane resin liquid in addition to the water, like the coagulating liquid. A dilute aqueous solution of the solvent can be used, but water is preferable from the viewpoints of handleability and environmental aspects.

Here, as a specific method of flowing the peeling liquid from the non-molding surface 12 into the through hole, for example, by pouring the peeling liquid into the concave liquid inlet 13 formed in the non-molding surface 12, The method of injecting is mentioned. The peeling liquid injected from the liquid injection port 13 in this manner flows through the through hole communicating with the liquid injection port 13, reaches the molding surface 11, and flows out from the molding surface 11. As a result, the peeling liquid gradually accumulates between the molding surface 11 and the seamless molded product attached thereto, and can be easily peeled off from the mold without damaging the seamless molded product. The production of products proceeds efficiently. Here, the usage amount of the peeling liquid is not particularly limited and can be set as appropriate. However, a range in which the peeling liquid outflow amount is 1 to 10 cm ³ per 1 cm ^{2 of the} molding surface is preferable. Within such a range, the seamless molded product can be easily peeled while further preventing breakage, and the peeling does not take a long time.

The peeling liquid may be injected manually by inclining the container in which the peeling liquid is placed, and pouring the peeling liquid into the liquid inlet 13, or with the liquid inlet 13 of the mold 11. You may carry out by the liquid injection means comprised by connecting a liquid injection pump with a pipe | tube.
Further, the liquid inlet 13 formed in this example is formed so that the peeling liquid can easily enter the through-hole from the non-molded surface 12, and is not necessarily formed.
Furthermore, as described above, a gas such as air or nitrogen can be used instead of the peeling liquid.

  Furthermore, it has already been described that when the solidification step is performed as shown in FIG. 4, the coagulation liquid flows from the non-molding surface 12 to the molding surface 11 through the through holes and can be solidified also from the inside. However, in that case, the solidification liquid filled in the through-holes gradually flows out of the molding surface 11 by gravity simply by pulling up the mold 10 from the coagulation bath 30, and this also acts as a peeling liquid. . In this way, a method in which the solidification step and the peeling step are continuously integrated is also efficient.

By performing the peeling step in this manner, a seamless molded product such as a three-dimensional glove along the molding surface 11 can be easily peeled off from the molding surface 11 without being damaged, and can be efficiently obtained.
After the peeling step, the seamless molded product is dried by a conventional method after washing with water using a water tank or a washing machine into which running water is introduced. The drying temperature is preferably 60 to 140 ° C.
Further, after drying, an appropriate post-treatment such as a water repellent treatment for imparting durable waterproofness to the seamless molded article may be performed. The water repellent treatment may be performed by a known method using a known water repellent. When the water repellent treatment is performed, it is preferable to further dry with an air oven or the like from the viewpoint of improving the quality of the seamless molded product.

The seamless molded product thus obtained has a waterproof property because it is seamless, and is formed from a polyurethane resin porous membrane, so that it has excellent conformability due to excellent stretchability and stretch recovery properties. Equipped with moisture permeability that allows vapors such as sweat to escape to the outside, and is excellent in workability. Further, by setting the thickness of the seamless molded product to, for example, 0.01 to 0.5 mm, more excellent shape compatibility can be obtained.
As such a seamless molded product, various three-dimensional molded products such as mittens, socks, stockings, and hats can be exemplified in addition to gloves, and there is no particular limitation. In the case of manufacturing these, molds having corresponding shapes may be used, and in the case of socks, a foot mold 40 as shown in FIG. 5 may be used. Also, there are no particular restrictions on the use, such as medical use, clean room use, sports use, outdoor use, etc.

  In addition, the seamless molded product thus obtained has sufficient stretchability, shape adaptability, and durability even if it has a single-layer structure made of a water-coagulable polyurethane resin porous membrane. However, depending on the purpose, a multilayer structure in which a plurality of water-coagulable polyurethane fat porous membranes are laminated may be used. In that case, the peeling process may be performed after the adhesion process and the solidification process are repeated according to the number of layers required.

Hereinafter, the present invention will be specifically described with reference to examples.
[Evaluation items and methods]
1) Moisture permeability The gloves obtained in each example were measured by the JIS L 1099 A-1 method (calcium chloride method). However, the unit was converted per 24 hours. The unit is g / (m ² · 24 hours).
2) Water pressure resistance The water pressure resistance of the gloves obtained in each example was measured.
The water pressure resistance was obtained by arranging the JIS L 1092 A method (low water pressure). A polyurethane film was cut out from the glove obtained in each example and used as a test piece. Specifically, water pressure was measured by applying water pressure to the test piece while preventing 210 pieces of polyamide (nylon) taffeta from overlapping the test piece and preventing the test piece from expanding. The unit was expressed in mmH ₂ O.
3) Extension recovery According to the method described in paragraph 0019 above.

Example 1
A polyester-based polyurethane resin liquid (viscosity 2250 mPa · s) having the following blending ratio (mass ratio) was prepared.
Next, an unglazed hand mold having the shape shown in FIG. 1, which is a mold for forming gloves, was immersed in this resin liquid for 1 minute, and an adhesion process for attaching the resin liquid to the molding surface was performed. This hand mold has a through-hole penetrating the molding surface and the non-molding surface, the porosity is 55%, and the average pore diameter is 200 μm.
Next, this unglazed hand mold was immersed in a coagulation bath made of water at 10 ° C. so that at least the adhered polyurethane resin liquid was immersed, and the coagulation step was performed by holding for 60 minutes.
Thereafter, the hand mold is pulled up from the coagulation bath, and water is injected from the liquid injection port formed on the non-molding surface of the hand mold so as to flow out about 1 to 10 cm ³ per 1 cm ² of the molding surface. The peeling process which peels off the molded article (gloves) of was performed. Furthermore, it wash | cleaned for 5 minutes using 50 degreeC warm water. The peeling process was very easy and there was no damage to the gloves.
100 parts of polyester polyurethane resin (CR8006HV) (solid content 30%, manufactured by Dainippon Ink & Chemicals, Inc.)
Dimethylformamide 100 parts Zinc pyrithione powder Nikkanon ZP 0.2 part (Nikka Chemical Co., Ltd.)
White pigment L5733 (manufactured by Dainippon Ink & Chemicals, Inc.) 2 parts Cross-linking agent Coronate HL 1 part (manufactured by Nippon Polyurethane Industry Co., Ltd.)

When the obtained gloves were dried at 60 ° C. and evaluated, the moisture permeability was 9000 g / (m ² · 24 hours), the water pressure resistance was 1000 mmH ₂ O, and the stretch recovery was 96%. The thickness was 175 μm and uniform.
An electron micrograph of the surface of the hand mold used is shown in FIG.

(Comparative Example 1)
The solidification process was performed in the same manner as in Example 1 except that a non-porous aluminum hand mold having no through holes was used as the hand mold, and then the polyurethane resin molded product was peeled off from the hand mold. It was difficult to peel off because it was in close contact with the hand mold.

(Example 2)
An ether-based polyurethane resin liquid (viscosity: 1220 mPa · s) having the following blending ratio (mass ratio) was prepared.
Then, a glove was obtained in the same manner as in Example 1 except that a hand-made mold having the shape shown in FIG. 1 was made of a tetrafluoroethylene polymer. This hand mold has a through hole penetrating the molding surface and the non-molding surface, the porosity is 60%, and the average pore diameter is 100 μm. Also, the peeling process was very simple and there was no damage to the gloves.
The results of evaluating the obtained gloves are shown in Table 1.
100 parts of ether-based polyurethane resin (CR1836P) (solid content 30%, manufactured by Dainippon Ink & Chemicals, Inc.)
Dimethylformamide 100 parts Zinc pyrithione powder Nikkanon ZP 0.2 part (Nikka Chemical Co., Ltd.)
White pigment L5733 (manufactured by Dainippon Ink & Chemicals, Inc.) 2 parts Cross-linking agent Coronate HL 1 part (manufactured by Nippon Polyurethane Industry Co., Ltd.)

When the obtained gloves were dried at 60 ° C. and evaluated, the moisture permeability was 9200 g / (m ² · 24 hours), the water pressure resistance was 1000 mmH ₂ O, and the stretch recovery was 92%. The thickness was uniform at 60 μm.

(Comparative Example 2)
The solidification process was performed in the same manner as in Example 2 except that a non-porous aluminum hand mold having no through holes was used as the hand mold, and then the polyurethane resin molded product was peeled from the hand mold. It was difficult to peel off because it was in close contact with the hand mold.

  Thus, in each example using a hand mold made of a porous material having a through-hole penetrating the molding surface and the non-molding surface, the peeling process can be performed very easily compared to the comparative example. It was possible to manufacture efficiently without inconvenience such as breaking the gloves.

It is a perspective view which shows an example of the shaping | molding die of this invention. It is explanatory drawing which shows an example of the adhesion process of this invention. It is explanatory drawing which shows an example of the coagulation process of this invention. It is explanatory drawing which shows another example of the coagulation process of this invention. It is a perspective view which shows another example of the shaping | molding die of this invention. It is the electron micrograph of the surface of the hand type used in the Example.

Explanation of symbols

10, 40 Mold 11 Mold surface 12 Non-mold surface

Claims (3)

A molding surface and a non-molding surface, which is a portion other than the molding surface, are formed on the outer surface, and a solution containing a water-solidifying polyurethane resin is attached to the molding surface, and the polyurethane resin is solidified with a coagulating liquid. A mold for producing a seamless molded product comprising a polyurethane resin porous membrane,
A molding die comprising a porous material having a through-hole penetrating the molding surface and the non-molding surface.   2. The mold according to claim 1, wherein the porous material is one selected from the group consisting of unglazed, ceramics, resin, and metal. The molding of the molding die made of a porous material having a molding surface and a non-molding surface which is a part other than the molding surface formed on the outer surface and having a through-hole penetrating the molding surface and the non-molding surface An adhesion step of attaching a solution containing a water-coagulable polyurethane resin to the surface;
Coagulating step of coagulating the polyurethane resin with a coagulating liquid to form a polyurethane resin porous membrane;
A peeling step of peeling a seamless molded product made of the polyurethane resin porous film from the molding surface by allowing a fluid to flow into the through-hole from the non-molding surface and outflowing the fluid from the molding surface. A process for producing a seamless molded product characterized by the above.

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