JPH0426477Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial use) This invention utilizes the retroreflection of light that glass beads have in space, that is, the property of spherical transparent glass spheres reflecting light in the direction in which it is incident. It is characterized by an elongated molded product, such as a string,
It is a molded product such as a pipe shape. Since the string-like and pipe-like molded products having the structure of the present invention reflect light, they can be used as signs for restricted areas at construction sites due to their marking ability. Molded products with a diameter of 1 cm or less are flexible, so secondary processing into ropes, nets, etc. is easy, and the ropes, nets, etc. obtained through secondary processing are used for signs at construction sites, airports, and power generation. It can be used in a number of ways, including as a mark when incorporated into fences at schools, exterior interior materials for protective and safety nets at ski resorts, fishing nets, etc.

(Prior Art) Many types of safety equipment and signs that have improved visibility by reflecting light have been put into practical use. For example, a transparent vinyl sheet with prismatic embossing on the back side (product name: Reflectite),
There is a product (trade name: Scottilite) in which fine glass beads are embedded or attached to a sheet or film. These are used for safety purposes by being attached to training suits, ski wear, transportation clothing, helmets, etc. For road construction signs, miniature light bulbs are placed at regular intervals in transparent thin-walled pipes to make them blink, and light bulbs are placed inside ropes at regular intervals in egg-shaped or basket-shaped molded products. There are products etc. There has also been an attempt to increase visibility at night by mixing yellow and black speckled ropes (tra ropes) used in road construction sites, no-trespassing signs, etc. with fluorescent agents or luminescent agents.

(Problems to be Solved by the Invention) The present invention has the problems of low visibility and high cost seen in conventional products. For example, metal wire nets are common for enclosing construction sites, ski resorts, etc., but as they get older, the wires can break and hurt people who jump out. Because of this, there was a risk of injury. Also, it was not possible to devise a method to reflect the light.

A tape that reflects light on the black part of a rope with yellow and black spots (Trarope) (product name: Scotch Tape)
The one wrapped around the black part lacks sharpness in the daytime, and the amount of light reflected at night is insufficient, and is expensive.

Construction site ropes with increased visibility using light bulbs have high visibility at night, but very low visibility during the day. Moreover, it is complicated to handle and expensive.

Fiber ropes mixed with fluorescent agents or luminescent agents have the disadvantage that their properties are lost in a short period of time because the fluorescent agents or luminescent agents are organic substances, and they are also expensive.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the basic means taken by the present invention will be explained with reference to the drawings. (including tape). To be more specific, it is a string-like body with a diameter of about 3 m/m made by stretching polyethylene spun 5 to 10 times in the vertical direction, and has several vertical grooves 2 on its surface. (Figure 2 shows the case of six grooves), and the size of the grooves 2 is determined by the size of the glass beads 3 (Figure 3) that fit into them. Since it is preferable to have a diameter of 400 to 600 microns, the shape of the groove 2 is U-shaped as seen in the cross-sectional view of FIG.
The bottom part is semicircular, and the top part is opened to the width of the diameter of the glass beads 3, or is opened slightly outward, and the depth is approximately equal to the diameter of the glass beads 3.
The point is that when the glass beads 3 are inserted, the top part 3a
is flush with the outer circumferential surface 1a of the core portion 1, or has a depth such that it slightly protrudes from the outer peripheral surface 1a. The number of grooves depends on the diameter of core 1.
If it is about 3 m/m, 5 to 6 pieces are preferable. This is an experimental value that sufficiently stimulates the sense of seeing light reflection and confirms the safety function, so it is not an absolute value. Glass beads 3 are fitted into the grooves 2 in a row or at certain intervals.

Next, the entire core 1 into which the glass beads 3 thus obtained are inserted is covered with a transparent synthetic resin film 4, and the inner surface 4a of the outer covering film 4 is covered with a transparent synthetic resin film 4.
is heat-adhered to both the top portion 3a of the glass bead 3 and the outer peripheral surface 1a of the core 1 to fix the glass bulb 3. The thus completed molded product is shown in FIG.

Note that the outer covering film 4 also has a core portion 1 on the glass bulb 3.
It is preferable to use a synthetic resin that adheres well to the core, and normally it is sufficient to use a synthetic resin that is the same type as the core or has properties similar to this. Further, it is necessary to appropriately select the material for the core 1 depending on the application, and once the material for the core 1 is determined, it is easy to select the outer film 4 accordingly.

The present invention is not limited to the above-mentioned content, but as the diameter of the core portion 1 increases, the number of grooves formed on the surface increases. Further, as the core becomes thicker, it becomes harder, so the axial center is formed in a hollow part 5 as shown in FIG. 4 to provide flexibility. When tensile strength is required, a rope or strand (bundle of fibers) can be inserted into the hollow portion 5. When the outer cover film 4 is colored, the reflected light 6D becomes the color of the colored film 4.
Further, the core portion 1 itself may be in the shape of a cylindrical outer tape.

(Function) To explain the function of the present invention, Fig. 3B-
In FIG. 6, which shows a cross section taken along the line B, incident light 6 entering the molded product of the present invention passes through the transparent covering film 4, is refracted and bent at the entrance 6a of the glass beads 3, and the glass beads 3 It passes through the inside of the bead 3 as 6X, is internally reflected at the bottom 3B, and returns to the inside of the bead 3 as 6X.
Y, and is refracted again at the exit 6C to become the incident light 6.
Since it returns in the same direction as reflected light 6D, it reflects light well when it is hit by car headlights, flashlights, or other lights at night. In other words, it is retroreflected. When the glass beads 3 are placed in resin, water, etc., the incident light passes through the glass beads 3, so no reflection occurs at the bottom 3B of the glass beads. This invention is glass beads that occur in space 3
It takes advantage of both the refraction and reflection properties of , and can provide very good retroreflection. Because these individual glass beads 3 are relatively large, the light is felt strongly, and because a large number of glass beads are lined up,
Since it reflects a lot of light as a whole, its presence is clearly visible and serves as a safety device.
During the daytime, the outer covering film 4 is transparent, so the core 1
Since the color of the surface is clearly visible, if the core is made in an appropriate color, for example, a tiger pattern, it will have a sufficient visibility effect during the day, so it can be used as a safety tool.

Products of this invention whose molecules are oriented in the form of fibers through stretching processing are strong and can be knitted into nets. The knots are also strong enough to be used as a safety net, and they also have retroreflective properties, and usually require several twisting processes to achieve this thickness (approximately 3 m/m). However, in the method of the present invention, the thickness is the same as the twisting process, so the twisting process is unnecessary, so it can be made at a very low cost. The product of the present invention can also be made flat, and by wrapping it around another object or applying adhesive to the back side, it can be used conveniently like an adhesive tape.

(Example) Embodiments of the present invention will be described with reference to the drawings.

Figures 1 to 3 show the basics of the molded product of the present invention; 1 is a core portion made of polyethylene with a diameter of 3 mm; 2 is a concave groove provided on the surface of the core portion;
Reference numeral 3 denotes glass beads that fit into the grooves, and are arranged in a line or at appropriate intervals in the grooves. Reference numeral 4 denotes a thin transparent outer covering film that entirely covers the core portion having the glass beads 3, and is thermally bonded to the top portion 3a of the glass bead 3 and the outer peripheral surface 1a of the core portion to fix the glass bead 3. Glass beads 3 having a diameter of 400 to 600 microns are effective. Several grooves 2 are normally formed on the surface of the core 1 (6 grooves are shown in FIGS. 1 to 3), and the bottom 2a of the grooves 2 are formed with glass beads 3.
The cross-sectional shape is approximately U-shaped. The depth of the groove also corresponds to the diameter of the glass bead 3, but the depth is such that the top 3a of the glass bead 3 is flush with the outer peripheral surface 1a of the core 1 or slightly protrudes from this. But that's fine. The outer covering film 4 is entirely covered with the glass beads 3 by an extruder equipped with a crosshead, and as shown in FIG.
And the glass beads 3 are fixed by thermal bonding to the outer circumferential surface 1a (the circumferential surface other than the groove) of the core portion 1. In this way, the molded product of the present invention is completed.

Since the light-reflective molded product of the present invention has the above-described structure, the lower part of the glass bead 3 is fitted into the bottom of the groove 2, as shown in FIG. There are only a few points of contact with the object, and most of it is in contact with the air, and it retroreflects light to the same degree as a glass bulb in the air. That is, in FIG. 6, incident light 6 enters the glass bulb from the upper part 6a, and becomes refracted light 6X within the bulb.
Next, this is reflected at the reflection point 6B on the bottom, and the reflected light 6Y
As a result, the inside of the sphere is reversed, and the light exits from the exit 6C of the spherical surface to become reflected light 6D. This light reflection phenomenon does not occur if the lower part of the glass bead is tightly wrapped in resin or submerged in water. The present invention was completed by researching this point and finding the above-mentioned means for successfully and integrally fixing the glass beads to the core without interfering with the light reflection phenomenon.

If the core 1 of the present invention is colored and the outer film 4 is made transparent, the color of the core can be easily seen during the day. On the other hand, if the outer film is colored, the color of the outer film will be visible during the day, and the reflected light will reveal the color of the film at night, making it possible to create a wide variety of products. The core can also be easily made into a yellow and black tiger pattern.

Next, another embodiment of the present invention will be described. First, let's talk about the molded product of this invention for making nets.
(Including 2 parts of color pigment) 70 parts High-density polyethylene (trade name Hi-Zex)
30 parts mixture.

(b) Low-density polyethylene as an outer covering film (Urtoxex above)
use.

The core 1 was melt-extruded and then stretched 9 times in the longitudinal direction to orient the molecules to obtain a molded product with a diameter of about 3 mm (FIG. 2). Six concave grooves 2 are provided at equal intervals on the surface, and the diameter of the glass beads 3 fitted into these is centered at 500 microns, which is the same as in the previous example.
The shape and dimensions of the groove 2 are also the same as in the previous example.

A covering film 4 was applied to the outside using an extruder equipped with a crosshead. The invented product made from this material has appropriate elongation, so the knots are in good condition during net making.
It is suitable for use in nets.

Next, what is shown in Fig. 4 has a hollow part 5 formed in the center of the core part 1, and the structure of the core part 1 is applicable to a string-like body with a diameter of about 5 to 6 mm to about 20 mm. be. More grooves 2 are provided on the surface, and the thicker the core 1, the more grooves 2, and the thinner the core 1, the fewer grooves.
The one shown in FIG. 4 is an example having 12 vertical grooves 2. This type of structure has flexibility in its thickness, so it is easy to handle.
Further, secondary processing is also easy. This product is effective because it reflects a large amount of light per piece. The diameter of the hollow portion 5 may be arbitrarily selected depending on the application. The size of the glass beads 3 may also be selected depending on the application. Further, when tensile strength is required, a rope or strand can be passed through the hollow part 5 for reinforcement.

In the case shown in FIG. 5, the core 1 is colored black and yellow, and one black C and two yellow D are twisted into a rope shape. In this case, it looks like a normal yellow and black tiger pattern during the day, and when the light from the hetlight hits it at night, the entire glass beads 3 reflect the light, so it looks very shiny. When the transparent film 4 on the surface is colored, colored reflected light can be obtained.

(Effect of the invention) The molded product of the invention has the above-mentioned structure and its function,
By using glass beads 3 with a large ratio of 400 to 500 microns, uniform reflected light can be obtained by narrowing the particle size distribution of glass beads 3.
By utilizing the internal reflective property of glass beads, the amount of reflected light can be used effectively, making it highly effective as a safety sign at night.On the other hand, it has high tensile strength and is easy to perform secondary processing. Because of this, it can be used as a net, meaning that the entire net reflects light, dramatically increasing its effectiveness as a safety sign.Compared to fibrous nets, there is no twisting process, so it is inexpensive compared to its effectiveness. It is of great practical value.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the appearance of the molded product of the present invention, Figure 2 is a cross-sectional view of the core, Figure 3 is a cross-sectional view of the molded product of the present invention, and Figure 4 is a cross-sectional view of the hollow molded product. 5 is a perspective view showing a state in which the hollow molded products are twisted together, and FIG. 6 is an explanatory diagram of the incidence and reflection of light. Code explanation, 1 core, 1a outer circumferential surface, 2 groove, 2a
Concave groove bottom, 3 glass beads, 3a top of glass beads, 3B bottom of inner surface of glass beads, 4 outer covering film 4, 4a inner surface of outer covering film, 5 hollow part, 6
Incident light, 6a glass bead entrance part, 6B internal reflection, 6C exit part from inside the glass bead, 6D reflected light, C black molded product, D yellow molded product.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A core part 1 made of synthetic resin with several grooves 2 provided on its surface, with glass beads 3 fitted in a row in the grooves 2, and then removed as a whole. The glass bead 3 is covered with a film 4 and the inner surface 4a of the film is thermally bonded to the top 3a of the glass bead 3 and the circumferential surface 1a of the core 1.
A light-reflective molded article made of glass beads, characterized in that it is fixed in the concave groove 2 without inhibiting the retroreflection of light by having a space other than a. (2) A light-reflective molded product made of glass beads according to claim 1 of the utility model registration claim, in which the core 1 has a hollow part 5 at its center. (3) A light-reflective molded product made of glass beads according to claim 1, in which the number of grooves 2 increases or decreases as the diameter of the core 1 increases or decreases. (4) A light-reflective molded product made of glass beads according to claim 1 or 2 of the utility model registration claim, in which a rope or strand (fiber bundle) is enclosed in the hollow part 5 of the core part 1.