JP2009263504A - Molding material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding material (molding material in a form of a cream) excellent in flexibility, having the degree of freedom of allowing a user to freely mold, having flexibility, pliability, (fluidity) and shape retention property, easy handling property, without causing sagging during manufacture, and giving a lightweight finish with a smooth surface after dried. <P>SOLUTION: The molding material is in a form of cream, prepared by intensive mixing of a composition comprising lightweight hollow microspheres, water, poly(vinyl alcohol) (PVA), and, if necessary, an optionally added binding material, glycerin, liquid paraffin and other powder material, and has pliability and sagging resistance. Preferably, the material is prepared by intensive mixing of at least lightweight hollow microspheres by 38 to 55 wt.%, water by 33 to 55 wt.% and poly(vinyl alcohol) (PVA) by 2 to 12 wt.%, and is configured to contain the binding material optionally added as required, by 0.3 to 5.0 wt.%. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a modeling material, for example, and particularly relates to a modeling material excellent in flexibility (fluidity).

  Conventionally, clay for handicrafts such as bread clay and paper clay is known as a modeling material used in arts and crafts for the purpose of modeling and making works.

  The present inventor has so far researched and developed various clay materials for handicrafts. For example, in the invention described in Japanese Patent Application Laid-Open No. 2007-331971 by the inventor of the present application, it has water resistance and is excellent in adhesiveness, has less stickiness and can be sharpened, and further has a shape retention after being dried. A clay having excellent durability has been developed and disclosed.

JP 2005-281634 A JP 2005-249811 A Japanese Patent No. 3076528

  In addition to the usefulness of the present invention, the present inventor will further improve the level of crafts, so that it has a more diverse texture (especially after drying), and can be more flexible during work. It is considered that higher performance such as shape retention is required after forming a one-end shape while being flexible and fluid (fluid). For example, we think that needs that could not be thought of with conventional clay expressions, such as expressing the feel of whipped cream with modeling materials, will be born in the near future.

  In addition, in the aspect of art education, etc. in kindergartens, elementary schools, junior high schools, high schools, etc., various expressions (textures: softness of touch, touch, Moisturizing feeling, texture, etc.) and various modeling workability (flexibility, shape retention, etc.) will be required. Especially infants don't have grip, so you can't use a squeeze bag unless the cream is made very soft.

  In this regard, so-called general lightweight clay has problems with flexibility during and / or after work, and is said to be incompatible with works that require a feeling of touch, such as (whipped) cream. I must. For example, the clay material described in Patent Document 1 has high transparency, excellent texture, etc., and retains high flexibility after drying, but there is a limit in flexibility during work, that is, modeling. was there.

  In the clay material described in Patent Document 2 described above, there remains a problem that an extra work for mixing and kneading the powder is required. In other words, in the clay material described in the document, when the clay is exposed to air, it will be cured in a relatively short time and the desired modeling cannot be performed. To avoid this, dissolve the clay material in water. Before kneading, that is, in a powder state, when used as clay, the powder must be mixed and kneaded. Therefore, it is not suitable for the purpose of simply forming clay with high formability.

  In addition, various lightweight clays used for modeling and creation have been known in the past, but none of them is flexible enough to make a whipped cream with a cream squeeze bag. However, there is a problem that it takes a lot of time and requires considerable squeezing force (grip strength) due to its hardness. Furthermore, even if it is squeezed somehow, the whip squeezed bag is broken, or there is a problem that it cannot be used for a plurality of times.

  On the other hand, there is a lightweight clay with flexibility (fluidity), but this is just like softening paper clay, and the problem is that the clay hangs down during modeling. There was a point.

  In other words, a modeling material with a higher level of expression and a greater variety of modeling work that can respond to advanced requirements such as whipping cream being expressed in clay while it does not drip. It can be said that the above-mentioned problems have not been substantially recognized so far. Furthermore, there has never been a modeling material that provides a solution to this problem. In addition, there was a sample cake made of silicone. In this regard, however, the silicone itself is expensive, so it was inappropriate for professional craftsmen to use as teaching materials or for children to play.

  The present invention is mainly aimed at solving such problems in the prior art, and is a problem of economically realizing a molding material having the above-described more advanced and various expressions and various modeling workability. For the first time, we will face each other and try to give a solution. The purpose is, for example, to be easy to use immediately, to have high flexibility, and to have droop resistance (during and / or after modeling), and in addition during production (whipped) The object of the present invention is to provide a molding material capable of realizing a variety of usage methods that can be used while being squeezed (in a cream squeezing bag or the like) (e.g., fluidity) with high economic efficiency.

  Another object of the present invention is that the drying time after modeling can be shortened compared to conventional ones, has simplicity, can prevent cracks that occur after drying the work, and has a certain form holding force that does not break easily It is to provide materials.

  In order to achieve such an object, the present inventor has conducted extensive research and development, and as a result, lightweight hollow microspheres, water, polyvinyl alcohol (PVA) at a constant ratio, that is, 20 to 80% by weight of lightweight hollow microspheres, By combining 30 to 75% by weight of water and 2 to 15% by weight of polyvinyl alcohol (PVA), it is possible to realize a paste-like or cream-like molding material with fluidity and shape retention, which is the object of the present application. Easy to use, flexible (flowable) with drooping resistance (during and / or after modeling), and a variety of usage methods that can be used while squeezing (with cream squeezing bags, etc.) We found that it can be achieved at the same time. In addition, the numerical value of the said weight% of a lightweight hollow microsphere is a number containing a water | moisture content, and the actual weight of solid content is about 11% among them. In other words, about 89% is water in a commercially available state. In other words, the solid content of the light-weight hollow microsphere that is “20% by weight” is approximately 2.2%, and if it is 80% by weight, it is 8.8%.

  As a result of further examination and research, these were in a specific numerical range, that is, at least 38 to 55% by weight of lightweight hollow microspheres, 33 to 55% by weight of water, and 2 to 12% by weight of polyvinyl alcohol (PVA). By kneading and mixing to include 0.3 to 5.0% by weight of a binder as necessary, it has been found that a molding material more suitable for achieving the purpose of the present application can be realized. It was.

  The lightweight hollow microspheres in the present invention are made of synthetic resin as partition walls, and the particle diameter is preferably 10 to 150 μm. The specific gravity of the lightweight hollow microsphere is preferably 0.5 or less, and more preferably about 0.01 to 0.1. When the light-weight hollow microsphere is commercially available, the water-containing state (water is 80 to 90% by weight) is used, but is not limited thereto. There are things that contain air other than air, such as hydrocarbons, and there are several types with an average particle size of 150 μm or less. If it is 20% by weight or less of the total amount in a water-containing state, shape retention is lost even if it can be squeezed out with a squeeze bag, and if it is added in an amount of 80% by weight or more, it is hard and cannot be squeezed out.

  The light-weight hollow microspheres in this case are mainly thermally expandable as described above, and are organic hollow microspheres having a shell wall made of vinylidene chloride-acrylonylol copolymer resin, or a resin not containing vinylidene chloride What consists of is preferable. Moreover, about other things, it is possible to use it in combination with each above-mentioned material.

  In addition, water having a water temperature of a certain level or more (in other words, water that feels warm to the human skin) is preferable, and hot water is preferred.

  Polyvinyl alcohol (PVA) is a water-soluble synthetic resin that is substantially white in the form of powder or granules. The change with humidity is relatively small, and it exhibits extremely high adhesion to many substances including cellulose, such as paper, fiber, and wood. The polyvinyl alcohol (PVA) in this case can prevent hardening and embrittlement without losing flexibility even under low humidity by using glycerin as a plasticizer. Furthermore, polyethylene glycol (PEG) or the like may be used as a plasticizer.

  As a caking additive added as needed, polyvinyl pyrrolidone can be mainly used in addition to polyvinyl alcohol (PVA). In addition, vinyl alcohol-alkyl vinyl ether copolymer, carboxymethyl cellulose (CMC), methyl cellulose (mc), hydroxymethyl cellulose, hydroxypropyl methylcellulose, polyamide, polyacrylamide, acrylamide, pregelatinized starch, polyethylene oxide, etc. alone or in combination May be used.

  By adding glycerin to polyvinyl alcohol (PVA) as described above, the flexibility of the polyvinyl alcohol (PVA) film can be maintained and the elongation can be increased.

  As other powders, corn starch, wheat flour, cereal flour or the like can be used as necessary. The microspheres themselves have a high degree of whiteness and are 90 or more, so when adding corn starch, it becomes close to cream. However, adding too much tends to cause cracks and shrinkage and increases the weight.

  Work that is particularly excellent in flexibility (fluidity) by kneading the clay composition composed of lightweight hollow microspheres, water, polyvinyl alcohol (PVA) and a caking additive added as necessary. It has a degree of freedom that can be freely shaped to the user's preference in the production of products, etc., while maintaining flexibility (fluidity) while maintaining a certain form during production, and easier handling It is possible to realize a modeling material with characteristics.

  The flexibility (fluidity) of the modeling material according to the present invention is exceptional as compared with the conventional one, and has a smooth characteristic like whipped cream. For example, when the shaping material according to the present invention is put into a squeezed bag of fresh cream with a nozzle attached and squeezed out, it can be squeezed out smoothly due to the excellent flexibility described above. In such a case, the conventional one breaks the bag when used about three times, but it has been confirmed by experiments described later that the molding material according to the present invention does not break even when it is used five times or more.

  Also, in the past, it was necessary to put the clay directly into a squeezed bag with a nozzle due to its hardness, but the molding material of the present invention has such flexibility (fluidity). Thus, each squeeze bag containing the product can be used in a squeeze bag with a nozzle. From the point that the bag can be used twice, there is also a practical effect that the nozzle can be easily replaced for the outer bag.

  In addition, the squeezed molding material has a shape retaining property that can maintain its shape in a good shape without being crushed, and can easily and easily form a nozzle squeeze mark when squeezing. .

  In addition, the modeling material has the characteristics that it has good elongation and good usability due to the blending condition of its components, and has high modeling properties. That is, as long as the clay is in a wet state even if it comes into contact with the air, the molding can be performed any number of times without curing. Even when cured, flexibility can be restored by mixing and kneading a small amount of water. This improves workability and workability.

  Furthermore, due to the characteristics resulting from such kneading, the production can be smoothly performed without dripping of the modeling material during the production. In addition, it has good adhesiveness and is optimal for the work of applying a spatula to a core material or foundation.

  About coloring, a color can be made to adhere by mixing a watercolor paint, an acrylic paint, and food coloring with this modeling material.

  After drying, it can be completed as a light and smooth surface such as polystyrene foam without causing cracks. A gentle and gentle texture can be produced from the appearance and the touch.

  On the other hand, the modeling material of the present invention is cured by leaving it to stand at room temperature and naturally drying, and the drying days are fast, and it can be dried by removing moisture in just one day.

  Therefore, it is possible to proceed smoothly without taking extra time for the process from drying after modeling to completion of the work.

  In addition, two different colors can be put together in one squeeze bag and two colors can be put out at the same time, so it is possible to express the so-called soft cream mix sold at general stores.

  Since the modeling material according to the present invention is configured as described above, the flexibility (fluidity) is remarkably high and the flexibility (fluidity) is due to the difference in the component ratio from the conventional one. However, it can be handled just like whipped cream while maintaining a certain unit.

  In addition, since the work of mixing and kneading the raw material powder has already been performed, it can be used immediately when producing a work.

  Furthermore, since it has a configuration rich in flexibility (fluidity) as described above, it can be used in various usage methods with a high degree of freedom. In other words, it can be easily stretched thinly with a hand or a spatula as it is, and the shaped material can be put into a squeeze bag of fresh cream with a nozzle attached and squeezed out for use. In addition, various other usage methods can be considered based on a free idea utilizing the flexibility (fluidity).

  In addition, the range of works that can be produced from such flexibility (fluidity) is wide, and it is also possible to make works having delicate parts that cannot be produced by clay with low flexibility (fluidity).

  In addition, when handling modeling materials, that is, when applying clay with hands or spatulas, and when squeezing and using it in a squeeze bag, it has flexibility (fluidity) that does not require strong force, so it can be a beginner It is easy to handle, and can be used easily by many people, from infants to the elderly, and everyone can enjoy the production of shaped objects widely.

  Furthermore, since it is configured as described above, the modeling material having such a configuration is not only used for clay for everyday entertainment and hobbies, such as clay for handicrafts, but also for various art fields such as aesthetic work production. In addition, the present invention can be effectively applied to a wide range of applications such as clay in the educational field such as for school teaching materials.

  Hereinafter, the best mode for carrying out the present invention will be described.

  Cream-shaped modeling materials (including clay and putty) having flexibility (fluidity) and shape retention according to an embodiment of the present invention are lightweight hollow microspheres, water, polyvinyl alcohol (PVA), and necessary It is a modeling material formed by kneading a caking composition and a clay composition made of glycerin, liquid paraffin, and other powder. The main configuration is as described above.

  Lightweight hollow microspheres that can be used in the present invention are mainly thermally expansible, organic hollow microspheres having a shell wall made of vinylidene chloride-acrylonylolyl copolymer resin or resins not containing vinylidene chloride. Is preferred. Others can be used in combination with them.

  The organic hollow microsphere may be a microsphere having a shell wall made of an organic material and having a gas void space inside. Organic hollow microspheres having a shell wall made of a vinylidene chloride-acrylonylol copolymer resin have a true specific gravity of about 0.01 to 0.05, a particle diameter of about 2 to 100 μm, and a whiteness of 90 or more. Since it has moderate elasticity, it is more preferable.

  Further, the water in this case also includes hot water, and it is preferable to mix at a ratio of about 33 to about 51% by weight as a whole.

  The polyvinyl alcohol (PVA) that can be used in the present invention is preferably mixed at a ratio of about 2 to about 11% by weight as a whole.

  Since the binder is as described above, the description is omitted here.

  However, since vinyl alcohol-alkyl vinyl ether copolymer and carboxymethyl cellulose (CMC) have high viscosity, it is difficult to squeeze when clay is put in a squeezed bag of fresh cream and used, and others are preferable.

  About other powder, it is preferable to use a corn starch in the ratio of about 15 weight% as a whole ratio as needed. It is also conceivable to use flour or the like. The microspheres themselves have a high degree of whiteness and are 90 or more, so when adding corn starch, it becomes close to cream. However, adding too much tends to cause cracks and shrinkage and increases the weight.

  Furthermore, it is also preferable to mix a preservative at a ratio of 0.1 to 0.4% by weight with respect to the total to prevent the molding material from being spoiled.

  Next, the function and usage of the modeling material according to the present invention configured as described above will be described.

  When utilizing the modeling material which concerns on one Embodiment of this invention, for example, a modeling material is put into the squeeze bag of fresh cream, and it squeezes out and uses. The material of this squeeze bag may be a polyester fiber coated with urethane resin, but it becomes a durable and expensive product for use by professional confectioners, so polyethylene sold in so-called 100-yen shops Can be used. The thickness may be about 0.055 mm, and can be used by putting about 60 g of the clay in a squeezed bag with a nozzle. In such a case, you can create a fine texture by squeezing out and enjoy making the work as if you were making a real cake. This is far beyond the conventional use of clay and the expression method using clay, and it opens up new possibilities for the expression of modeling materials.

  In addition, due to the suitability of the adhesion of the molding material, the molding material according to the present invention is most suitable for the operation of applying a spatula to a core material or a base. Such a core material is made of polystyrene foam, sponge, plate, glass, PET bottle, etc. Cardboard, cloth, etc. are conceivable. Also, as a work, you can decorate artificial products such as beads, plastic strawberries and petals on the squeezed items, and you can enjoy them as accessories after drying.

  On the other hand, the modeling material of the present invention is cured by leaving it to stand at room temperature and naturally drying, and the drying days are fast, and it can be dried by removing moisture in just one day. Furthermore, after drying, it is finished to feel like a foamed polystyrene and does not cause cracks, and the appearance can be completed beautifully.

<Example A>
Next, the present invention will be described by way of examples. However, these examples are only examples of the present invention, and the scope of rights and the scope of implementation of the present invention are not limited by these examples.
(1) Manufacture of modeling material Table 1 is a figure which shows the evaluation regarding the compounding component and property (characteristics) of the modeling material which concern on Example 1 to Example 4 of this invention.

  As shown in Table 1, for Examples 1 to 4, lightweight hollow microspheres (water content 80 to 90%) were 41.5 to 75.1% by weight, and hot water was 20.2 to 51.6% by weight. , 2-10 wt% of polyvinyl alcohol (PVA) is blended in a predetermined combination, carboxymethyl cellulose (CMC) is 0.5 wt%, corn starch is 17.5 wt%, glycerin is 2 wt%, if necessary It is a modeling material obtained by blending and kneading 2% by weight of paraffin, 3.7% by weight of pregelatinized starch, and 0.2% by weight of preservatives.

This table also shows evaluations regarding the blending components and properties (characteristics) of the clay according to conventional Comparative Examples A and B.

  As shown in Table 1, Comparative Examples A and B are based on a conventional blending method. As lightweight hollow microspheres, F30E is 22.0 to 24.5% by weight, and hot water is 57.7 to 59.0. Wt%, polyvinyl alcohol (PVA) 3.5 wt%, carboxymethylcellulose (CMC) 5.5-9.5 wt%, glycerin 3.7-4.3 wt%, liquid paraffin 4.9- It is a clay (cream-shaped modeling material) obtained by blending 5.0% by weight and preservative in a proportion of 0.2% by weight and kneading.

(2) Properties of modeling material For Examples 1 to 4, in Table 1, the degree of drying after one day of natural drying, the degree of drawing (ease of drawing operation), flexibility (fluidity), shape retention, cracking The evaluation of each example was given as an objective evaluation by an expert with respect to the characteristics of the spread and the characteristics of the spread. Furthermore, comprehensive evaluation based on these characteristics was given. As evaluation results, ◎ indicates very good, ○ indicates good, and Δ indicates not so good.

  About comparative example (conventional example) A and B, in the said points about the clay by the conventional compounding method, in the said table | surface, the property of the clay seen from the same reference | standard as the above, and the comprehensive evaluation judged from those viewpoints Is what we asked for. As evaluation results, ◎ indicates that it is very good, ○ indicates that it is good, Δ indicates that it is not very good, and &#9747; indicates that it is bad.

As can be understood from Table 1, the molding material obtained in the examples according to the present invention compared with those obtained by the conventional blending method can be drawn while maintaining good properties in terms of viscosity, flexibility, and fluidity. It also has good properties in terms of softness and shape retention. Furthermore, according to the conventional blending method, it is very good in terms of spreading, but is somewhat lacking in terms of drawing, softness and shape retention, it is obtained in the examples according to the present invention. The modeling material has goodness from all the viewpoints of the above evaluation criteria.
<Example B: Experiment on Whip Characteristics>
Next, regarding the modeling material according to the present application, since the characteristics of the whipped modeling material (cream-shaped modeling material) have been confirmed through experiments, this will be described.

A comparison is made between the conventional whipped product and the product according to the present application.
(1) As an experimental experiment method for checking the protection against cream squeezed bags, the following are used as commercially available “cream squeezed bags”.
Bag material Polyethylene thickness 0.055mm
60 g of modeling material is inserted. FIG. 1 is a photograph for explaining cracks of a product applied to a cardboard of another company's product (conventional product).

As shown in the figure, the other company's products are severely cracked after drying, and this makes it impossible to create a practical work.
(2) Experiment for Observing Crack Resistance FIG. 2 is a photograph for explaining the crack characteristics of another company's product (bottom photo: conventional product) compared to the present invention product on the photo. As is apparent from the figure, the conventional product has severe cracks after drying, and it is recognized that the conventional product is considerably inferior in softness.
(3) Experiment for viewing softness FIGS. 3 and 4 are photographs showing the results of a softness experiment.

  For whipped bags and modeling materials, squeeze the modeling material directly into the bag with the left nozzle.

  As shown in FIGS. 3 and 4, the squeezed with the whipped double bag can be easily squeezed because it is soft (fluid), and the squeezed molding material does not sag or break.

  On the other hand, the clay according to the prior art is hard (no fluidity), so some of the clay has been squeezed directly into a bag with a nozzle, which is inferior in terms of softness as a whole. Is confirmed.

  As for the product after squeezing with a whip, the product according to the present application can double the bag (from the above), so that the nozzle can be easily replaced. Therefore, it was possible to continue the work by changing only the contents one after another in the bag with the changed nozzle.

  In this regard, according to the prior art (conventional product), refilling clay into a bag with a different nozzle forces the user to do extra work, and the user feels bothersome and inconvenient. In addition to learning, it was impossible to perform a rapid modeling operation in a limited time.

  On the other hand, in the present application, in addition to the softness, it is possible to immerse yourself in the work without being forced to take extra time, so it is convenient for the user and is softer (has fluidity), This gives rise to an unprecedented feature that gives you the freedom to activate the playfulness that is important to the work of modeling, and that you can also change your time and effort. In these respects, a means for solving the problem recognized for the first time by the present application, that is, realization of a lightweight modeling material having more advanced and various expressions and various modeling workability, is provided.

  As described above in detail, according to the modeling material according to the present invention, it is excellent in flexibility and has a good feeling of use and good adhesion even in a variety of usage methods and in a soft state. The property and formability can be kept high. Furthermore, if the modeling material is in a moist state, the modeling can be performed any number of times without curing, so that workability and workability can be improved.

  Furthermore, if the modeling material according to the present invention has various qualities as a modeling material mainly based on such flexibility (fluidity), it will greatly stimulate the user's will to create. Is possible.

  Therefore, according to the modeling material according to the present invention, the flexibility (fluidity) is particularly excellent, and it has a degree of freedom in which it can be freely shaped to the user's preference in the production of works and the like, while being soft. In addition, it is easy to handle and maintains a certain unity and retention during production, and can be smoothly executed without dripping of the molding material during production, and it is lightweight and cracked after drying. You can complete a model with a smooth surface that doesn't fit.

  Also, as shown in Fig. 5, two different colors can be put together in one squeeze bag and two colors can be put out at the same time, so the so-called soft cream mix sold at general stores can be expressed. It became so.

  The present invention is not limited to the above-described embodiment, and various modifications, additions, substitutions, expansions, reductions, etc. to the above-described embodiment are allowed within the scope of the same and equivalent technical idea. Is. For example, although it demonstrated as a modeling raw material in the above-mentioned description, it is not limited to clay, The technical idea which concerns on this application is applicable even if it does not take this form. Specifically, the same idea can be realized for industrial putty and the like. The details will be changed with the above description, and the description here will be omitted.

  Moreover, what was mentioned above only showed an example of embodiment for embodying the technical idea which concerns on this application, and the technical idea which concerns on this application is applicable also to other embodiment. For example, although described above as a modeling material, the possibility of being realized by other applicable materials such as a clay-like composition, an adhesive, a putty, etc., used for the fixed structure is not excluded. These are all included in the scope of the technical idea of the present application.

  Furthermore, for example, in the above description, the technical idea of the present invention has been described as a modeling material alone, but the present invention may be realized as a modeling material in which these modeling materials are collectively formed. These embodiments are also included.

  Further, even if a product or method produced using the present invention is applied to the secondary product and commercialized, the value of the present invention is not reduced at all.

  According to the modeling material according to the present invention, it is particularly excellent in flexibility due to the characteristics formed by kneading the molding material composition consisting of lightweight hollow microspheres, water, polyvinyl alcohol (PVA) and a caking additive added as necessary. It has the flexibility to be freely shaped to the user's preference in the production of works, etc., and can be easily handled while maintaining a certain unit during production while being soft. is there.

  In addition, the modeling material according to the present invention has a fast drying time and can be dried in just one day, and can be completed as a lightweight and smooth surface such as polystyrene foam without causing cracks after drying. From its appearance and feel, it can give a gentle and gentle texture.

  Furthermore, it is easy for beginners to handle due to the flexibility, and it can be used easily by many people from infants to the elderly, and everyone can enjoy the production of shaped objects widely.

  In addition, it can be effectively applied to a wide range of applications such as modeling materials in the field of education such as the handicrafts field, the art field, and school materials.

It is the photograph for explaining the crack about the thing applied to the cardboard of the other company's product (conventional product). It is a photograph for demonstrating a crack about the product of another company (the bottom of the conventional product photograph, and the photograph is the present invention product). It is a photograph which shows the result of the experiment for seeing the said softness. It is a photograph which shows the result of the experiment for seeing the said softness. In the product according to the present application, it is a photograph showing that two colors can be put out simultaneously by putting two different colors in one squeeze bag.

Claims (3)

  A molding material formed by kneading at least 20 to 80% by weight of lightweight hollow microspheres, 30 to 75% by weight of water, and 2 to 15% by weight of polyvinyl alcohol (PVA).   The molding material according to claim 1, wherein at least 38 to 55% by weight of lightweight hollow microspheres, 33 to 55% by weight of water, and 2 to 12% by weight of polyvinyl alcohol (PVA) are kneaded, and if necessary, viscous A modeling material containing 0.3 to 5.0% by weight of a binder.   The binder is polyvinyl pyrrolidone, modified polyvinyl alcohol (vinyl alcohol-alkyl vinyl ether copolymer), carboxymethyl cellulose (CMC), methyl cellulose (mc), hydroxymethyl cellulose, hydroxypropyl methylcellulose, polyamide, polyacrylamide, acrylamide, α The modeling material according to claim 2, wherein the molding material is one or more selected from the group consisting of modified starch and polyethylene oxide.