JP2006002298A - Helmet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a helmet capable of suppressing rise of temperature in the interior of the helmet under the scorching sun by blocking infrared light which sunlight emits. <P>SOLUTION: The helmet is obtained by further forming a resin layer having an infrared light-blocking function at least on the outer surface of a helmet and the resin layer is composed of a resin composition containing an infrared light-blocking agent. The resin composition preferably further comprises a polyurethane-based resin and a curing agent and the content of the infrared light-blocking agent is preferably 15-45 wt.% based on total of the resin composition and the infrared light-blocking agent comprises, preferably, titanium oxide. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a helmet.

Many conventional helmets are formed of a single layer of reinforced resin such as FRP or thermoplastic resin. When worn in work under hot weather, the temperature rise inside the helmet caused by sunlight, especially infrared rays, is sometimes It was dangerous for safety because it reduced consciousness and dulled reflexes.
As a means for suppressing the temperature rise in the helmet worn under such a hot sun, a technique for discharging moisture inside the helmet by forming a fine gap in the material of the outer shell of the helmet (for example, see Patent Document 1), Although a technique for mounting a cold insulation bag in order to remove moisture and heat from the inside of the top of the helmet is also disclosed (for example, see Patent Document 2), it has been difficult to shield infrared rays from solar radiation. On the other hand, although the technique as an infrared shielding material is also disclosed (for example, refer patent document 3), the helmet which can shield the infrared rays by solar radiation efficiently did not exist.
JP 2001-248010 A JP 2001-355116 A Japanese Patent Laid-Open No. 10-120946

  An object of the present invention is to provide a helmet that can suppress a temperature rise inside the helmet due to infrared rays of solar radiation that could not be achieved by the prior art.

Such an object is achieved by the present invention described in (1) to (7).
(1) A helmet in which a resin layer having an infrared shielding function is further formed on at least an outer surface of the helmet, wherein the resin layer is made of a resin composition containing an infrared shielding agent.
(2) The helmet according to (1), wherein the resin composition further contains a polyurethane resin-based paint.
(3) The helmet according to (1) or (2), wherein the content of the infrared shielding agent is 15 to 45% by weight with respect to the entire resin composition.
(4) The helmet according to any one of (1) to (3), wherein an average particle diameter of the infrared shielding agent is in a range of 0.5 to 3 μm.
(5) The helmet according to any one of (1) to (4), wherein the infrared shielding agent includes titanium oxide.
(6) The helmet according to (5), wherein the crystal form of the titanium oxide is a rutile form.
(7) The helmet according to any one of claims 1 to 6, wherein the resin layer has a thickness of 0.1 to 1.0 mm.

  In the present invention, by providing a resin layer containing an infrared shielding agent on at least the outer surface of the helmet, it is possible to efficiently shield the infrared rays of solar radiation and to suppress the temperature rise inside the helmet.

Hereinafter, the helmet of the present invention will be described.
The present invention is a helmet in which a resin layer having an infrared shielding function is further formed at least on the outer surface of the helmet, wherein the resin layer is made of a resin composition containing an infrared shielding agent. .
Although the material which comprises the helmet main body of this invention is not specifically limited, For example, although unsaturated polyester resin, ABS resin, polyethylene resin, polycarbonate resin, AES resin, polypropylene resin etc. are mentioned, any resin can be used. .

The helmet of the present invention is characterized by further having a resin layer containing an infrared shielding agent on at least the outer surface of the helmet body.
The helmet of the present invention has a form in which a resin layer is formed on the outer surface of the helmet body, a form in which a resin layer is formed alone on the inner surface of the helmet, and a form in which resin layers are formed on both the inner and outer surfaces. You can also.

  The infrared shielding agent is not particularly limited, and examples thereof include titanium oxide, zinc oxide, cerium oxide and the like. Among these, it is preferable to use titanium oxide. By using titanium oxide, the infrared shielding effect can be improved.

Titanium oxide is a generic term for white pigments made from ilmenite ore. It has excellent heat resistance (melting point 1825 ° C) and chemical resistance compared to other white pigments (zinc white, lithopone, lead white, etc.) and reflects at the same time. The refractive index is extremely high (95% or more in the wavelength range of 500 to 700 μm), and the refractive index is the highest among white pigments.
The form is white powder, and it is used in various fields such as various paints, printing inks, plastics, papermaking, chemical fibers, rubber, titanium capacitors, paints, crayons, ceramics, and electronic materials.

  Titanium oxide can be classified into a rutile form and an anatase form according to the crystal form. The rutile form has a specific gravity (rutile form: 4.2, anatase form: 3.9) and a refractive index slightly higher than the anatase form (rutile form: 2.71, anatase form: 2.52), absorption of light near the ultraviolet region is large, and thermal conductivity is small (rutile form: 0.148 cal / cm.sec. ° C., anatase form: 0.43 cal) /Cm.sec.° C.).

The scientific basis for the high infrared shielding properties of titanium oxide is not clear, but it is presumed that the reflectance and refractive index are both high. And it is thought that the effect which suppresses the temperature rise inside a helmet can be heightened with such a synergistic effect with high infrared shielding property and small thermal conductivity.
The crystal form of titanium oxide used in the present invention is preferably a rutile form. By using the rutile form, the effect of infrared shielding is improved.

Although content of an infrared shielding agent is not specifically limited, 15 to 45 weight% is preferable with respect to the whole resin composition. More preferably, it is 20 to 40% by weight. If the content of the infrared shielding agent is less than the lower limit, the effect of improving the infrared shielding properties may be reduced. If the content exceeds the upper limit, the proportion of the infrared shielding agent in the resin composition becomes too large, and the coating efficiency May decrease and the weight of the helmet may increase due to the large specific gravity.
The content of titanium white used in ordinary white-painted helmets is about 2% by weight with respect to the entire paint, and there is almost no infrared shielding property. As a major element of the present invention, the content of titanium oxide is remarkably higher than that used in ordinary white coating, whereby the infrared shielding property can be remarkably improved.

The average particle size of the infrared shielding agent is not particularly limited, but is preferably in the range of 0.5 to 3 μm. Furthermore, 0.7-1.5 micrometers is preferable. If the average particle size of the infrared shielding agent is less than the lower limit, the effect of improving infrared shielding may be reduced, and if the upper limit is exceeded, it may be difficult to evenly distribute in the paint, resulting in uneven coating There is. If uneven coating occurs, the effect of improving the infrared shielding property may be reduced as a result.
Usually, the particle size of titanium oxide used for the pigment is 0.2 to less than 0.5 μm, and it is known that the infrared shielding rate is not sufficient. A further preferable element of the present invention is that the particle size of the infrared shielding agent is within the above range, whereby the infrared shielding property can be remarkably improved.

  In the present invention, it is preferable to use a polyurethane resin-based paint as the resin composition. Although it does not specifically limit as a polyurethane resin type coating material, For example, a two-part type of a polyol and a polyisocyanate, a mixed type of an acrylic polyol, a polyisocyanate compound and a cyanate compound, etc. are mentioned as a composition. A mold is preferred. By using this two-pack type, it is possible to perform coating with a glossy appearance and excellent appearance, and this gloss further improves the effect of suppressing the temperature rise in the helmet with excellent sunlight reflectivity. it can. Moreover, by using this polyurethane resin-based paint, the scratch resistance and durability are improved.

  The content of the polyurethane resin-based paint is not particularly limited, but is preferably 30 to 70% by weight with respect to the entire resin composition. More preferably, it is 40 to 60% by weight. When the content of the polyurethane resin-based paint is less than the lower limit, glossiness is lost, and the effect of improving scratch resistance and durability may be reduced. If the upper limit is exceeded, uneven coating may occur, resulting in poor appearance.

  Furthermore, it is preferable that the resin composition usually contains a curing agent used for helmet coating. Although content of a hardening | curing agent is not specifically limited, 10-30 weight% is preferable with respect to the said whole resin composition, Furthermore, 15-25 weight% is preferable. If the content of the curing agent is less than the lower limit, it takes time to cure the coating, and if it exceeds the upper limit, the viscosity of the coating may increase and work efficiency may deteriorate.

  In addition, the resin composition can appropriately contain an appropriate amount of a pigment, an oil-based paint, a weathering agent, and the like.

  Furthermore, thinner can be used as a diluent in the resin composition. The content of the thinner is not particularly limited, but is preferably 25 to 55 parts by weight with respect to 100 parts by weight of the resin composition. More preferably, it is 30-50 weight part. If the thinner content is less than the lower limit, the resin composition may not be sufficiently diluted and the appearance may be poor. If the upper limit is exceeded, a sufficient amount may not be applied due to excessive dilution. By using thinner as a diluent, a spray paint that can be applied with an air spray gun described later can be obtained.

The spray paint used in the present invention can be produced by the method described below, but is not limited thereto.
First, an appropriate amount of the above-mentioned polyurethane resin paint, curing agent and titanium oxide is added into a small stirrer and stirred at a low speed for several minutes to several tens of minutes to prepare a resin composition.
Next, an appropriate amount of thinner is added and the mixture is further stirred for about several minutes to obtain a titanium oxide-containing spray paint.
In addition to the above method, titanium oxide can be uniformly dispersed in the coating solution by using ceramic beads including, for example, silica beads, titania beads, zirconia beads, and glass beads as media.

The method of applying the spray paint of the present invention to the helmet is not particularly limited, and examples thereof include spray paint, brush paint, dipping and the like. Among these, spray coating is preferable because of high work efficiency and enabling uniform coating.
Although it does not specifically limit as a spray painting instrument, It is preferable to use an air spray gun. Uniform coating can be achieved in a short time by using an air spray gun.
Furthermore, it is preferable to use a jig that can fix and rotate the helmet during painting. By using this jig, uniform coating can be performed in a short time.

  In the helmet of the present invention, the thickness of the resin layer formed from the spray paint is not particularly limited, but is preferably 0.1 to 1.0 mm. More preferably, it is 0.15-0.5 mm. If the thickness of the resin layer is less than the lower limit value, the infrared shielding effect is lowered. If the resin layer thickness exceeds the upper limit value, the coating time becomes longer and work efficiency is lowered, and the helmet may be heavy.

  Hereinafter, the present invention will be further described with reference to Examples and Comparative Examples.

(Example) 53% by weight of polyurethane-based resin paint, 27% by weight of titanium oxide, and 20% by weight of a curing agent are blended with respect to the entire resin composition, and 50 rpm with a small stirrer (Ishikawa-type stirrer) After preparing a resin composition by stirring for 10 minutes, 40 parts by weight of thinner was added to 100 parts by weight of this resin composition and further stirred for 5 minutes to obtain a spray paint. The obtained paint was applied to an FRP helmet attached to a rotating jig with a spraying pressure of 0.4 Mpa and a spraying time of 15 seconds using an air spray gun, and then dried at 70 ° C. for 30 minutes in a dryer, and the outer surface of the helmet A coated helmet having a 0.25 mm resin layer was obtained.

(Comparative example) An unpainted white FRP helmet (manufactured by Sumitomo Bakelite Co., Ltd .: FAV) was used.

The composition of the paint used in the examples is as follows.
(1) Polyurethane-based resin paint: for S-500S helmet manufactured by Nagashima Special Paint Co., Ltd. (2) Thinner: No2 synthetic thinner manufactured by Atmix Co., Ltd. 1.0 μm, rutile type) was stirred for 10 minutes with an Ishikawa stirring and pickling machine (No. 6R-E manufactured by Ishikawa Factory) (A-WM type).
(4) Hardener: Kaya Ester O-50E manufactured by Kayaku Akzo

Table 1 shows the infrared shielding effect, appearance and weight of Examples and Comparative Examples.
(Measuring method)
The temperature is measured by placing an temperature sensor (AP-320) manufactured by Anritsu Keiki Co., Ltd. inside the helmet under hot weather, and using an thermometer made by Anritsu Keiki Co., Ltd. (AP-320K printer built-in 2ch type) for 1 hour every 10 minutes. The maximum temperature during the measurement was taken, and the difference from the outside temperature was quantified. The outside air temperature and the temperature inside the comparative example were the same temperature.

The appearance was evaluated according to the following criteria.
(Unevenness)
X: There are irregularities on the surface.
○: Some unevenness on the surface.
A: There is no unevenness on the surface.
(Glossy)
X: There is no gloss.
○: Some glossiness.
A: Glossy.
As shown by the above results, the weight of the example was increased by about 50 g compared with the comparative example without coating, but it was confirmed that the appearance was excellent and the solar radiation infrared shielding property was excellent.

Table 2 shows the results of measuring the temperature difference inside the helmet between the painted product and the non-painted product of the present invention in a state closer to actual wearing. Measurements 1 to 3 are measured on different days.
(Measuring method)
FIG. 1 shows the temperature measurement points. The temperature is measured by installing temperature sensors (AP-320) manufactured by Anritsu Keiki Co., Ltd. in both parts a and b, and using an thermometer made by Anritsu Keiki Co., Ltd. (AP-320K printer built-in 2ch type) at intervals of 10 minutes. Measured for 1 hour and recorded the maximum temperature.
Moreover, the lower stage of the Example on each measurement date shows a temperature difference with the comparative example.
As shown in the results of Table 2, the temperature inside the painted helmet (Example) is a maximum of 8.3 ° C. lower than that of the non-painted helmet (Comparative Example). It was confirmed that it was big.

  The helmet of the present invention can be suitably used for work under hot weather because it is possible to suppress the temperature rise in the helmet due to solar radiation infrared shielding more than a normal helmet.

Schematic showing the measurement location of the temperature in the helmet

Explanation of symbols

a: Back surface of the top of the helmet b: 5 cm below the a

Claims (7)

A helmet in which a resin layer having an infrared shielding function is further formed on at least an outer surface of the helmet, wherein the resin layer is made of a resin composition containing an infrared shielding agent. The helmet according to claim 1, wherein the resin composition further contains a polyurethane resin-based paint. The helmet according to claim 1 or 2, wherein the content of the infrared shielding agent is 15 to 45 wt% with respect to the entire resin composition. The helmet according to any one of claims 1 to 3, wherein an average particle diameter of the infrared shielding agent is in a range of 0.5 to 3 µm. The helmet according to claim 1, wherein the infrared shielding agent contains titanium oxide. The helmet according to claim 5, wherein a crystal form of the titanium oxide is a rutile form. The helmet according to any one of claims 1 to 6, wherein the resin layer has a thickness of 0.1 to 1.0 mm.

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