JP2007290219A - Cushion mold modeling material and modeling method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cushion mold modeling material which can simply and directly model a human body without using gypsum or the like, does not need special heating for heat curing, and can control a heating temperature to prevent the human body from being damaged during heat curing and a modeling method using the material. <P>SOLUTION: The modeling method includes the steps for: preparing at least a first component (polyol) and a second component (isocyanate) separately out of polyurethane raw materials; preparing a chair fitted with a cushion which is used as a mold; covering the surface of the cushion of the chair with an empty polyethylene bag; covering the surface of the polyethylene bag with a nonwoven fabric; compounding raw materials; seating a model human body on the nonwoven fabric; injecting the compounded raw materials into the polyethylene bag; making the model human body lean gradually against the back supporting part of the polyethylene bag; and separating the model human body from the polyethylene bag. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cushion-type molding material such as a chair and a molding method, and more particularly, to a cushion-type molding material that directly molds from a human body and a molding method using the same.

In recent years, various types of manufacturing have been performed that accurately match the dimensions of the human body.
For example, in the manufacture of a chair, the seat surface, the shape of the backrest, and the cushioning properties are precisely matched to the shape of the human body.
In the production of wheelchairs and welfare chairs suitable for the elderly and the disabled, shapes that accurately match the dimensions of the human body are also required.

In order to satisfy these requirements, it is necessary to mold the human body.
Conventionally, when preparing a human body, for example, a beaded bag is prepared and the inside of the bag is evacuated, and then there is a formwork (seat surface, backrest, armrest, etc. A slightly large chair shape) is covered, and the target human body is seated thereon, and then a human body mold is first taken and the mold is dropped again into a plaster mold.
This method is very time consuming and laborious, requires three steps of bead type (concave type)-provisional type (convex type)-gypsum type (concave type), and the process is long and the processing of gypsum is complicated. is there.

Therefore, various mold making methods that do not use gypsum have been proposed.
For example, Patent Document 1 states that “a yarn of a thermoplastic resin that is fused to each other by heating to a predetermined temperature and then cured at a temperature lower than the predetermined temperature, or a yarn of a thermosetting resin that is cured at a predetermined temperature”. If a knit is formed as a knitting yarn and this knit is attached to the molding target, the knit will have a high fit without being pressed against the molding target due to the high elasticity of the knit. The technique is disclosed in which the knit surface in such a state is heated to maintain the mold forming state and mold.

However, if this method is used when the object to be molded is a human body such as a cushion type, if the thermosetting temperature of the thermoplastic resin (thread) is high, the human body will be injured such as a burn, and if it is low, the object to be molded Since it hardens even at normal temperatures before being attached to the heat design, it becomes difficult to design heat.
JP 2004-339651 A

  The object of the present invention, which has been made in order to solve various problems in the cushion mold molding material and mold molding method as described above, is a cushion mold that can be easily molded directly from the human body without using gypsum or the like. The object of the present invention is to provide a collecting material and a mold-making method.

  Another object of the present invention is to provide a cushion molding material and a molding method that do not require special heating during thermosetting and that can control the heat generation temperature during thermosetting to a level that does not cause injury to the human body. There is to do.

  In order to solve the above problems, a cushion-type mold material according to the present invention comprises, as shown in claim 1, a polyurethane raw material, a polyethylene bag containing the polyurethane raw material mixed therein, and the polyethylene And a non-woven fabric covering the bag.

  In addition, as shown in claim 2, the raw material of the polyurethane includes a first component made of a mixture of a glycerin-based polyol and a polymer polyol, a second component made of an isocyanate containing a carbodi-modified polymer, and an amine-based resinification catalyst. And an amine-based foaming catalyst, an amine-based crosslinking agent, and a foaming agent.

  In order to solve the above problems, the cushion mold molding method according to the present invention comprises at least a first component (polyol) and a second component (isocyanate) among polyurethane raw materials as shown in claim 3. A step of preparing separately, a step of providing a chair that also serves as a formwork, a step of covering a cushion, a step of covering the surface of the cushion of the chair with an empty polyethylene bag, and a step of covering the surface of the polyethylene bag with a nonwoven fabric A step of formulating the raw material, a step in which the model human body is seated on the non-woven fabric, a step of injecting the prepared raw material into the polyethylene bag, and a step in which the model human body is gradually applied to the back portion of the polyethylene bag. And the step of detaching the model human body from the polyethylene bag. The features.

  According to a fourth aspect of the present invention, the raw material of the polyurethane includes a first component composed of a mixture of a glycerin-based polyol and a polymer polyol, a second component composed of an isocyanate containing a carbodi-modified polymer, and an amine-based resinification catalyst. (A tertiary amine or the like), an amine-based foaming catalyst, an amine-based crosslinking agent (such as a triamine), and a foaming agent.

  According to the cushion-type mold material of the present invention, since polyurethane is used, it is easy to mold directly from the human body without using gypsum or the like, and no special heating is required for thermosetting. Coverage is obtained.

  According to the cushion type molding method of the present invention, since polyurethane is used, it is easy to mold directly from the human body without using gypsum, etc., and no special heating is required for thermal curing. Thus, a cushion-type molding method can be obtained in which the heat generation temperature can be controlled to a temperature that does not cause injury to the human body.

  Hereinafter, embodiments and effects according to the present invention will be described in detail with reference to FIGS.

In the present invention, if a thermosetting resin of a type that is produced by mixing two chemicals as a mold material and is generated by a self-heating polymerization reaction is applied, no extra heating is required, that is, the human body is damaged. Note that it is possible to mold the human body.
If the two-drug mixed type is used, polymerization and curing will not occur as long as the two agents are kept separate, so mixing can be performed immediately before molding without restriction on location and time even at room temperature. .

As such a type of thermosetting resin, a polyurethane-based resin is preferable from the viewpoints of safety, stability, economy, and controllability of various properties including foamability, hardness, and elasticity.
Polyurethane is generally produced by a polymerization reaction of a diol (first component, HO—R—OH) and a diisocyanate (second component, OCN—R′—NCO).
That is, this is due to addition polymerization of a hydroxyl group (—OH) of the first component and an isocyanate group (—NCO) of the second component by a urethane bond (—NHCOO—).

The exothermic temperature is a function of the rate of the polymerization reaction, the heat capacity of the drug, and the thermal conductivity of the drug. Since the rate of the polymerization reaction itself increases rapidly with temperature, the time course of the exothermic temperature generally draws a bell-shaped curve.
Therefore, in general, when shaping the shape of the human body, a rapid exothermic reaction occurs due to the mixing of the two drugs, and when a normal industrial chemical is used as it is, the peak value of the exothermic temperature rises to about 88 ° C., for example. There is a risk of burns due to the heavy burden on the human body.

In this example, a mixture of glycerin polyol and polymer polyol was used as the first component, and a carbodi-modified polymer was used as the second component diisocyanate, thereby adjusting the reaction rate and suppressing an increase in the peak value of the exothermic temperature.
Furthermore, the surface contacting the human body of the bag containing and mixing these drugs was covered with a non-woven fabric to enhance the heat insulation.
As a result, the maximum value of the exothermic temperature (on the surface of the nonwoven fabric in contact with the human body) could be suppressed to about 46 ° C. after 5 minutes from the start of the seating, that is, the reaction.

  Further, when the first component is a diol (having two hydroxyl groups), only a straight chain is formed, but in this example, a polyol (having three or more hydroxyl groups) is used. The number of crosslinks can be controlled by the ratio of the second component to the first component, and therefore the hardness and elasticity of the final product polyurethane can be controlled to the desired values.

Further, when an amine-based cross-linking agent such as triamine is added as a cross-linking agent, the amino group (—NH ₂ ) contained therein is more rapidly converted to the second component cyanate group (—OH) than the first component hydroxyl group (—OH). -NCO) to form urea bonds (-NH-CO-NH-), so that the hardness and elasticity values as well as the reaction rate can be achieved by adjusting the ratio of these amine-based crosslinking agents. Can be controlled.

  In addition, urethane bonds can be promoted by adding amine catalysts such as tertiary amines instead of ordinary tin catalysts as resinification catalysts. Therefore, by adjusting the ratio of these amine catalysts, the reaction rate can be increased. The hardness and elasticity can be controlled to be desirable values.

In adopting the nonwoven fabric, a preliminary experiment was conducted to determine the thickness required for the nonwoven fabric as a heat insulating material.
Actually, tissue paper was used instead of the non-woven fabric, and a commercially available hot plate was used as a heating device for increasing the temperature.
The number of tissue papers was changed, the tissue papers were spread on a hot plate set at 100 ° C., and the change over time in the temperature of the upper surface was measured.
The results are shown in FIG.

According to FIG. 1, the heat insulation effect is not necessarily sufficient when 1 to 4 sheets of tissue paper are stacked, but a sufficient heat insulation effect is obtained when 8 or more sheets are stacked.
Therefore, it is considered that the thickness of the non-woven fabric is about 8 sheets of tissue paper.

FIG. 2 shows a molding procedure according to this embodiment, and details of each step are as follows.
In step S0, the first component polyol, the second component diisocyanate, and various catalysts (foaming catalyst, resinating catalyst), cross-linking agent, and / or foaming agent, which are raw materials of the molding material, are separated. Be prepared.

The polyol as the first component is a mixture of a glycerin-based polyol and a polymer polyol. Among these, the glycerin-based polyol is a glycerin / polyalkylene oxide adduct:
_{CH 2 ((OR) k OH} ) -CH ((OR) m OH) -CH 2 ((OR) n OH).
Here, R is an alkylene group having 1, 2, or 3 carbon atoms, and k + m + n is an integer having a hydroxyl value of 20 to 35 (mgKOH / g).
The polymer polyol is a homopolymer of any one of polyethylene glycol, polypropylene glycol, and polybutylene glycol, a copolymer containing these, or a mixture of these homopolymers and / or copolymers.

The diisocyanate as the second component is diisocyanate alone or a carbodi-modified polymer (also referred to as modified polyisocyanate or carbodiamide modification) such as a urea-binding compound of two molecules of diisocyanate and diamine.
Further, the diisocyanate is any of 4,4′-diphenylmethane diisocyanate (MDI), tolyl diisocyanate, and hexamethylene diisocyanate, or a mixture thereof.
The diamine is any one of phenylene diamine, ethylene diamine, butylene diamine, hexamethylene diamine, or a mixture thereof.

  The resinification catalyst, the foaming catalyst, and the crosslinking agent are each a tertiary amine such as triethylamine, or a triamine such as block amine + aminoethyl alcohol or diethyltriamine.

Specific examples of these raw materials used in the experiment are shown in Table 1.
The required total weight of the first component and the second component is typically about 2 kg in the case of a cushion-type mold corresponding to a portion of the chair cushion where the human body is in contact with the seat surface and the backrest.

FIG. 3 is a schematic diagram showing the following step S9, that is, a completed state of the molding material 30, and is a cross-sectional view taken along the midline of the chair 10 and the model human body 90 seated on the chair.
In step S1, a chair 10 that also serves as a mold is prepared. In the present embodiment, cushions 12 and 14 are respectively disposed on the seat surface portion and the backrest portion of the chair.
In step S <b> 2, the surface of the chair cushion is covered with an empty polyethylene bag 40.
In step S <b> 3, the non-woven fabric 50 covers the surface of the polyethylene bag 40 that is not in contact with the chair.
In step S4, the above raw materials are prepared, poured into a polyethylene bag, and wait for 1.5 minutes.
In step S5, the model human body 90 moves and takes a natural sitting posture on the nonwoven fabric covering the polyethylene bag.
In step S6, the raw material is additionally injected into the polyethylene bag and waits for 2 minutes.
In step S7, the model human body is gradually applied to the back portion of the polyethylene bag and waits for 1.5 minutes.
In step S8, the model human body 90 is detached from the polyethylene bag and left for about 1 hour.
In step S <b> 9, the mold material 30 is completed, and a concave mold including at least the back portion 93, the heel portion 94, and the thigh portion 95 of the model human body 90 can be taken.

FIG. 4 shows the relationship between each of the above steps and the change in the temperature of the polyurethane raw material and the temperature (nonwoven fabric surface temperature) due to heat generation.
When the raw materials are prepared in step S4, the initial reaction (foaming reaction) starts, the temperature gradually increases from room temperature (T0 = 25 ° C.), and reaches about T1 = 28 ° C. after about 1.5 minutes.
When the model human body comes into contact with the raw material through the polyethylene bag and the non-woven fabric in steps S5 and S6, a pressure corresponding to the shape of the human body model is applied to the raw material whose resinification proceeds as the temperature rises.
When the temperature reaches about T2 = 37 ° C. in step S7, the shape of the model body, particularly the back, is given to the raw material.
Immediately before step S8, gelation of the raw material starts, the shape of the raw material is substantially fixed, the temperature of the raw material reaches about T3 = 42 ° C., and reaches the model body detachment temperature.
In step S8, the model human body is detached from the polyethylene bag, and during the subsequent standing time, the raw material is naturally cooled past the peak temperature T4 = 45 ° C. and returned to room temperature, and the curing (resinization) reaction is completed.
Switching to each of steps S5, S7, and S8 is determined based on the elapsed time as described above. However, the temperature of the raw material may be monitored, and the switching may be performed with the set temperatures T1, T2, and T3.

According to this method, it is possible to manufacture a cushion-type molding material for a chair in a short time and in a manner that does not load the human body.
In addition, when making the chair formwork, the relative position of the seating surface, back surface (backrest surface), and both sides (armrest surface) should be adjustable. The mold material to be used is created, divided into a seating surface, a back surface, and both sides. Further, a mold material having a different relative position is manufactured and divided in the same manner.
By combining them, the molding material corresponding to the chairs with different sizes can be provided with good appearance and at low cost.

It is a figure which shows the temperature measurement result of the tissue paper upper surface spread on the hotplate based on Example 2. FIG. It is a figure which shows the mold taking procedure based on Example 2. FIG. It is a schematic diagram which shows the completion state of the shaping material based on Example 2, and is sectional drawing along the midline of the model human body seated on the chair and the chair. It is a figure which shows the relationship between each step shown in FIG. 2, and the change of the temperature by the change of a polyurethane raw material, and heat_generation | fever.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Chair 12 Seat cushion 14 Back cushion 30 Molding material 40 Polyethylene bag 50 Non-woven fabric 90 Model human body 93 Back part 94 Hip part 95 Thigh part

Claims (4)

  A cushion mold material formed by using a model human body on a mold comprising a chair having at least a seat cushion and a back cushion, comprising a polyurethane raw material, a polyethylene bag and a non-woven fabric, A cushion covering the formwork, covering the exposed surface of the polyethylene bag with the nonwoven fabric, sitting on a model human body from the nonwoven fabric, and mixing and storing the polyurethane raw material in the polyethylene bag Mold material for molds.   The polyurethane raw material is a first component composed of a mixture of glycerin-based polyol and polymer polyol, a second component composed of isocyanate containing a carbodi-modified polymer, an amine-based resinification catalyst, an amine-based foaming catalyst, 2. The cushion-type mold taking material according to claim 1, comprising an amine-based crosslinking agent and a foaming agent.   Among the raw materials of polyurethane, at least a first component (polyol) and a second component (isocyanate) are separately prepared, a step of preparing a chair that also serves as a mold and a cushion is provided; Covering the surface with an empty polyethylene bag, covering the surface of the polyethylene bag with a non-woven fabric, preparing the raw material, sitting a model human body on the non-woven fabric, and adding the prepared raw material to the non-woven fabric Cushion-type mold comprising the steps of injecting into a polyethylene bag, the step where the model human body is gradually applied to a backrest portion of the polyethylene bag, and the step where the model human body is detached from the polyethylene bag How to take.   The polyurethane raw material is a first component composed of a mixture of glycerin-based polyol and polymer polyol, a second component composed of isocyanate containing a carbodi-modified polymer, an amine-based resinification catalyst, an amine-based foaming catalyst, 4. The cushion mold making method according to claim 3, comprising an amine-based crosslinking agent and a foaming agent.

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