JPH0470962B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present application applies decorative or This invention relates to a molding method for imparting safety.

(Prior art) Conventionally, methods for imparting decorative properties to cement or concrete molded products include adding pearl powder or coloring agents to a composition such as cement and curing it, or painting the surface of the molded product. A commonly used method for imparting elasticity to the surface of a cement or concrete molded product is to adhere a rubber or plastic molded product to a molded product such as concrete at a desired position using an adhesive.

However, it is impossible to impart shock absorption properties by blending coloring agents into compositions such as concrete, and methods of painting on the surface of cured materials such as concrete require the use of elastic materials as paints. If you select , it is possible to have both decorative properties and shock absorption properties, but in the case of concrete and other molded objects that have a three-dimensional shape, paint may drip or
The disadvantage is that it requires a lot of man-hours to apply thick coating, and pre-cured concrete and other molded products have poor adhesion to urethane elastomer, making it impossible to use them for practical use. It was hot.

Furthermore, the method of adhering to a molded product such as concrete using an adhesive is difficult in the case of a molded product such as concrete that has a three-dimensional shape.

(Problems to be Solved by the Invention) The present application seeks to obtain a molded product of concrete, etc., which has strong adhesion to concrete, etc., has external decorative properties, and has an external surface with high impact absorption properties. be.

(Means for Solving the Problems) The inventors of the present application have found that when a molded product such as concrete is pre-formed and a urethane elastomer stock solution is poured into it and the two are integrally molded, the bond between the two However, if the urethane elastomer is first molded and then a composition such as concrete is poured into an integral mold, the adhesive will be relatively strong, and the bond will be even stronger. It was discovered that an integrally molded product having practical decorative properties, elasticity, and adhesive properties can be obtained by using an anchor material in order to improve adhesive properties.
This has led to the completion of this application.

The molding method of this application involves applying a mold release agent to the mold,
It basically consists of 5 steps: casting and curing of urethane elastomer stock solution, partial burying of anchor material, casting and curing of compositions such as concrete, and curing and demolding. A coating film forming step can be added between the releasing agent application step and the urethane elastomer stock solution casting step. Alternatively, instead of this coating film forming step, a method may be adopted in which, after curing and demolding, a commercially available paint having desired properties is applied by means such as spraying.

Examples of molds used in this application include metal, rubber, plastic, or ceramic molds, such as electroforming molds, aluminum or iron molds, silicone rubber molds, urethane rubber molds, FRP molds, and plaster molds. It will be done.

As the mold release agent previously applied to the mold, a known silicone-based, wax-based, or fluororesin-based release agent is used. In addition, when using a mold such as a silicone mold whose mold material itself has mold releasability, application of a mold release agent can be omitted. Further, a mold for molding the urethane elastomer layer (preforming mold) and a mold for molding a composition such as concrete (main molding mold) may be used separately, but the same mold can also be used together. Note that when a silicone mold is used, post-painting after molding is easy because no mold release agent is used.

Another way to increase decorativeness is to apply a coating film to the cavity surface of the molding mold in advance, using a known rubber or synthetic resin-based paint that is color-matched to the desired color and is non-tarnishing or resistant to discolouration. Paint can be used. Examples of paints used in this case include:
Urethane-based, acrylic-based, vinyl-based, styrene-butadiene-based paints, etc. are suitable.

The urethane elastomer stock solution used in this application includes a stock solution for polyether-based or polyester-based urethane elastomers known for use in waterproofing, painted floors, and the soles of cast tires and footwear, such as Soflan Floor manufactured by Toyo Rubber Industries. From those that can be cured at room temperature to those that can be cured by heat, such as #206, #207 or Soflan SS, Vulkollan manufactured by Bayer, Adiprene manufactured by Dupont, Coronate 4046, 4048 and curing agent 4038 system manufactured by Nippon Polyurethane Industries, etc. All can be used. If it is desired to further increase the elasticity, it is also possible to use a mixture of these with a foaming agent, or a general-purpose urethane bumper or urethane stock solution for integral skin foam. It is important that the coating thickness of the urethane elastomer stock solution be as thick as necessary and sufficient to impart shock absorption properties to the surface layer of the final molded product and improve safety. One method for thick coating can be achieved by placing a mold horizontally and pouring (pouring and spreading, ie, casting) a urethane elastomer stock solution.

Anchor materials that can be used in this application include gravel,
In addition to crushed stones, ceramics, glass beads, glass balloons, perlite, shirasu balloons, etc., granular graphite, granular calcium carbonate,
A perforated plate such as lath metal or wire mesh can also be used.

The anchor material is not simply attached or adhered to the urethane elastomer layer, but it is necessary to partially bury it inside the urethane elastomer layer, as shown in Figure 1D, in order to improve adhesion to the internal concrete layer. be. The timing of embedding is after the urithane elastomer stock solution starts to gel and increases in viscosity, but before curing is completed. Before gelation, the anchor material was buried (too much) in the surface layer of the urethane elastomer (in other words, up to the inner surface of the mold), which not only worsened the appearance of the final molded product but also compromised safety such as cushioning properties. It will also be a loss. After curing, it becomes difficult to bury the anchor material.

As compositions such as concrete, known cement mixtures, concrete compositions containing gravel or the like, plaster or mortar compositions, compositions containing these mixed with synthetic resins, etc. can be used.

(Example) An example in which a plate-shaped body such as a frame for a sandbox is formed will be described. As shown in Figures 1A to 1E, a silicone rubber mold with an L-shaped cross section with a wood grain pattern formed on the cavity surface is opened into a flat plate, and approximately 25 μm of non-yellowing urethane paint (Rethane Nu manufactured by Kansai Paint Co., Ltd.) is applied to the mold. It was spray coated to form a thick film and allowed to dry for 5 minutes. Next, Toyo Rubber Industries' Soflan SS-75-12 stock solution (moisture-curing urethane resin) was applied with a brush to a thickness of approximately 10 mm. This stock solution is 60
The fluidity disappears after about a minute, so after 30 minutes after application, add dry gravel with a diameter of 10 to 20 mm to the Soflan SS-
It was spread on the coated surface of 75-12 at intervals of about 20 to 30 mm and allowed to harden naturally. The gravel hardened while being partially buried in the Soflan SS-75-12 coating layer due to its own weight. After returning the silicone mold to an L-shape and leaving it for 3 hours, the mold was removed and set in a concrete mold as shown in the diagram. Fresh concrete was poured in and cured in the usual manner to obtain an integral molded product. Ta. The resulting columnar molded product is a urethane elastomer integral concrete molded product with a wood grain pattern on the top and side surfaces, and is used as a frame around the sandbox with the urethane elastomer layer exposed on the outside as shown in Figure 2. there was.

This provides a safe space for children to wrestle in the sandbox, or even if they fall violently, they won't be seriously injured.

(Effects of the Invention) As described in the Examples, the method of the present application can produce molded objects with three-dimensional complex shapes, which have been difficult to achieve in the past, such as cement or concrete animals and play equipment installed in parks, etc. It is possible to obtain a soft and highly decorative material, which not only makes it extremely safe for children to play with, but also can be used to add decorativeness to buildings such as pillars, or to add elasticity. It is also possible to increase safety by making it last longer. Furthermore, it is extremely effective in protecting the edges of molded products such as concrete, which are easily damaged during transportation by being chipped or broken, such as the legs of animal-shaped molded objects. Ta.

[Brief explanation of drawings]

FIGS. 1A to 1E are process explanatory diagrams showing an example of the molding method of the present application, and FIG. 2 is a partial perspective view of a skin-integrated concrete molded product obtained by the process of FIG. 1. 1: silicone rubber mold, 2: paint spray gun, 3: urethane paint, 4: coating film, 5: urethane elastomer layer, 6: gravel, 7: concrete composition, 8: concrete cured product, 9: concrete mold .

Claims (1)

[Scope of Claims] 1. A urethane elastomer stock solution is applied to the inner surface of the mold, and at the stage where the urethane elastomer stock solution starts to gel and hardening is not completed, an anchor material is partially embedded in the urethane elastomer layer and hardened, and then cement or A method for forming a molded product such as skin-integrated concrete, which is characterized by pouring a concrete composition, etc., and integrally curing and molding the product. 2. Place a preforming mold made of silicone rubber with an L-shaped cross section in an open state, and apply the urethane elastomer stock solution to a thickness of about 10 mm on the inner surface of the cavity of the mold, until the urethane elastomer stock solution begins to gel. After the hardening is completed, the diameter may change.
Anchor materials of 10 mm to 20 mm are scattered on the surface coated with the urethane elastomer stock solution at intervals of 20 mm to 30 mm, and the anchor materials are partially buried in the urethane elastomer layer due to their own weight, and then the urethane elastomer layer is buried. After curing and integrating the preform, the preform is returned to an L-shape, and the urethane elastomer layer is further sufficiently hardened, removed from the mold, and set in the main mold made of concrete. A method for molding molded products such as skin-integrated concrete, which is characterized by pouring materials, etc. and hardening and molding them in one piece. 3. The molding method according to claim 1 or 2, wherein the urethane elastomer stock solution is foamable with a foaming agent added thereto.