JPH10245711A - Helmet with transparent visor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a helmet with a wide scope and a strong and transparent visor, by making the visor transparent, excellent in impact resistance and hardly breakable. SOLUTION: In this helmet comprising a transparent visor bonded to an opaque main body part, the visor is obtained by molding (A) an aromatic polycarbonate resin containing a polyorganosiloxane block or a mixture of the resin A and (B) an aromatic polycarbonate resin containing no polyorganosiloxane block having 0.1-10wt.% of polyorganosiloxane content.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a helmet equipped with a transparent visor, and more particularly to a helmet in which an opaque main body is joined to a visor molded of a polycarbonate-polyorganosiloxane copolymer. is there.

[0002]

2. Description of the Related Art Polycarbonate resin is an engineering plastic having excellent impact resistance and heat resistance. Among them, helmets are used for applications that take advantage of their excellent impact resistance. The design of modern helmets is diverse and one of them is with a visor.

However, in general, helmets are opaque by coloring polycarbonate resin, ABS resin, etc.
Some with a visor have a narrow field of view. Therefore, a transparent visor is desired. Therefore, there has been proposed a technique of performing insert molding in which only the visor portion is formed of a transparent polycarbonate resin, and the visor portion is previously charged and molded in a mold of a helmet. However, when an impact is applied to the visor of the helmet obtained by the technique, there is a problem that the helmet is detached from the helmet body or the visor is cracked.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a helmet with a transparent visor which is transparent and has excellent impact resistance and is resistant to cracking, and has a wide field of view and a strong visor.

[0005]

Means for Solving the Problems The present inventors have made intensive studies on the above problems, and as a result, have completed the present invention having the following gist. (1) In a helmet in which a transparent visor is joined to an opaque main body, the visor is made of an aromatic polycarbonate resin (A) containing a block of polyorganosiloxane or an aromatic resin not containing a block of the resin (A) and polyorganosiloxane. A helmet with a transparent visor molded from a mixture of a polycarbonate resin (B) having a polyorganosiloxane content of 0.1 to 10% by weight. (2) The helmet with a transparent visor according to the above (1), wherein the repeating unit of the polyorganosiloxane is represented by the formula (I).

[0006]

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[R ^a and R ^b are an alkyl group having 1 to 6 carbon atoms or a phenyl group, which may be the same or different. ]

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. (1) Aromatic polycarbonate resin containing a polyorganosiloxane block An aromatic polycarbonate resin containing a polyorganosiloxane block typically contains the above-mentioned repeating unit (I), and more specifically, Examples are polyorganosiloxanes of the formula (II) and (III
) A block copolymer with an aromatic polycarbonate comprising a repeating unit represented by the formula:

[0009]

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[R ^{1 to} R ⁴ are alkyl groups having 1 to 8 carbon atoms (for example, methyl group, ethyl group, propyl group, n-butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, etc.) 6-20, preferably 6-18 aryl groups (e.g. phenyl, tolyl, xylyl,
A naphthyl group), which may be the same or different. A is a divalent organic residue containing an aliphatic or aromatic group, for example, a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, an ethylidene group, an isopropylidene group, a cyclopentylene group, and a cyclohexylene group. , Cyclopentylidene group, cyclohexylidene group and the like, o-allylphenol residue, p
-Vinylphenol residues, eugenol residues, bisphenol A residues and the like. n is 1 to 60. ]

[0011]

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[R ⁵ and R ⁶ are a halogen atom (a chlorine atom, a bromine atom, a fluorine atom, an iodine atom) and an alkyl group having 1 to 8 carbon atoms (eg, a methyl group, an ethyl group, a propyl group, an n-
Butyl group, isobutyl group, amyl group, isoamyl group, hexyl group, etc.) or 6-20 carbon atoms, preferably 6-1 carbon atoms.
And 8 aryl groups (for example, a phenyl group, a tolyl group, a xylyl group, and a naphthyl group), which may be the same or different. p and q are 0-4. Z is a single bond, an alkylene group having 1 to 20, preferably 2 to 18 carbon atoms or an alkylidene group (for example, a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, an ethylidene group, an isopropylidene group, etc.) A C5-20 cycloalkylene group or a cycloalkylidene group (e.g., a cyclopentylene group, a cyclohexylene group, a cyclopentylidene group, a cyclohexylidene group, etc.), an alkylene ester group, an alkylenecarbonyl group, -O-,- S -, - SO ₂ -, or -CO
-Indicates a bond represented by a bond. m is 1 to 150. In the block copolymer, when the repeating units of the above formulas (II) and (III) are represented by II and III, respectively, III-II-
There are type III, type III-II, type II-III-II and multi-block type, but any type may be used. In particular, the type III-II-III, which has a simple production process, can be suitably used. Since high impact resistance is required, it is preferable that the number n of repeating siloxane units is large, but if n exceeds 60, it becomes cloudy. Therefore, it is usually in the range of 1 to 60, preferably 5 to 4.
0, more preferably 10 to 30 are suitable for molding transparent helmet visors.

The aromatic polycarbonate-polyorganosiloxane block copolymer of the present invention (the above III-II type)
Is described in JP-A-7-292113 by the present applicant. Specifically, the polycarbonate oligomer and the one-end-blocked polyorganosiloxane are separately produced, and the organic solvent is used in an amount of 0.12 to 35 parts by weight of the one-end-blocked polyorganosiloxane with respect to 100 parts by weight of the polycarbonate oligomer. And an aqueous solution of an alkali metal hydroxide of a dihydric phenol or a terminal stopper of a monohydric phenol. Further, a tertiary amine or a quaternary ammonium salt usually used as a catalyst in the production of polycarbonate is added. By performing an interfacial polycondensation reaction using such a catalyst, a polycarbonate-polyorganosiloxane block copolymer can be obtained.

As a typical method for producing a polyorganosiloxane having one end blocked, a haloformate group represented by the general formula (V) is added to 1 mol of a polyorganosiloxane having both ends reactive represented by the following formula (IV). Alternatively, by reacting a compound having a carboxylic acid halide group or the like, that is, a modifying agent in an amount of 0.1 mol or more and less than 2 mol, a modified polyorganosiloxane having one end capped represented by the formula (VI) can be produced. .

[0015]

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[R ^{1 to} R ⁴ and A are the same as those in the above formula (II). ]

[0017]

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[X is a halogen atom, D is a single bond or -O
-Indicates binding. R ⁷ represents a group represented by an alkyl group having 1 to 20 carbon atoms or an arylalkyl group having 7 to 20 carbon atoms. ]

[0019]

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[R ^{1 to} R ⁴ and A are the same as in the above formula (II), and D and R ⁷ are the same as in the above formula (V). As a typical method for producing a polycarbonate oligomer, a dihydric phenol 10 represented by the following general formula (VII) is used.
A polycarbonate oligomer having formula (III) obtained by mixing and optionally reacting a catalyst such as triethylamine in a solvent such as methylene chloride at a ratio of 110 to 150 moles of phosgene to 0 moles is obtained. be able to.

[0021]

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[R ⁵ , R ⁶ , Z, p and q are represented by the above formula (III)
Is the same as). Usually, in the production of a copolymer, a homopolymer of a polycarbonate is also produced, which is substantially a mixture of the copolymer and the homopolycarbonate. In the present invention, this is referred to as an “aromatic containing a block of polyorganosiloxane. It is referred to as "polycarbonate resin" or simply "copolymer".

Other aromatic polycarbonate resins containing polyorganosiloxane blocks include graft copolymers in which polysiloxane repeating units are graft-polymerized. A typical polymer structure is composed of a polysiloxane moiety represented by the formula (VIII) and a main repeating unit represented by the formula (III).

[0024]

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[R ⁵ , R ⁶ , p, and q are the same as those in the above formula (III). Z is an alkylene group, an alkylene ester group, or an alkylene carbonyl group among those shown in the above formula (III). R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are an alkyl group or an aryl group. k is 0 to 1000
It is. Specifically, the polysiloxane group is polydimethylsiloxane, polydiethylsiloxane, polydiphenylsiloxane, polymethylphenylsiloxane, or the like. The dihydric phenol having an unsaturated group that reacts with polysiloxane is 4
-Methyl-2,4-bis (4-hydroxyphenyl)-
1-pentene, 4-methyl-2,4-bis (4-hydroxyphenyl) -2-pentene, 4,4′-bis (4-
(Hydroxyphenyl) -1-pentene, 4,4′-dihydroxychalcone, 2,2′-bis (4-hydroxyphenyl) -2-acryloyltan, 1,3-bis (4-
(Hydroxyphenyl) -2-buten-1-one.

[0026]

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[R ⁵ , R ⁶ , Z, p, q, and m are the same as those in the above formula (III). The graft copolymer is disclosed in JP-A-7-16589.
No. 7 is described. The terminal terminator may have any structure as long as it is a monohydric phenol, and is not particularly limited. For example, p-tert-butylphenol, p-tert-octylphenol, p-cumylphenol, phenol, p-tert-amylphenol, p-nonylphenol, p-cresol, tribromophenol, p-tert-butylphenol
Bromophenol, 4-hydroxybenzophenone and the like can be mentioned, and these may be used alone or in combination of two or more.

Further, a branching agent may be used in combination as long as the effects of the present invention are not impaired. 1,1,1-Tris as branching agent
(4-hydroxyphenyl) ethane, α, α ', α''-tris
(4-hydroxyphenyl) -1,3,5-triisopropylbenzene, 1- [α-methyl-α- (4′hydroxyphenyl) ethyl] -4- [α ′, α′-bis (4 ''- Compounds having three or more functional groups such as [hydroxyphenyl) ethyl] benzenephloroglucin, trimellitic acid, and isatin bis (o-cresol) are suitable.

(2) Aromatic polycarbonate resin not containing a polyorganosiloxane block In the present invention, a homopolymer of an aromatic polycarbonate, that is, a polyorganosiloxane block may be added to the copolymer of (1) if necessary. It is possible to use a mixture of aromatic polycarbonates not containing.

The aromatic polycarbonate usually has the same repeating unit as that of the above formula (III).
It can be easily produced by reacting a polyhydric phenol with a phosgene or a carbonate compound by a known method such as an interfacial polymerization method, and there is no particular limitation on raw materials, production methods and the like. Examples of dihydric phenols include hydroquinone, 4,4'-dihydroxydiphenyl, bis (4-hydroxyphenyl)
Alkane, bis (4-hydroxyphenyl) cycloalkane, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenylsulfone, bis (4-hydroxyphenyl) ketone, 9,9 2, bis (4-hydroxyphenyl) propane (bisphenol A) is suitable among them, and biscarbonate compounds such as diphenyl carbonate are preferred. Dialkyl carbonates such as diaryl carbonate, dimethyl carbonate and dimethyl carbonate.

The terminal terminator may be of any structure as long as it is a monohydric phenol, and is not particularly limited. For example, p-tert-butylphenol, p-tert-octylphenol, p-cumylphenol, phenol, p-
tert-amylphenol, p-nonylphenol, p-cresol, tribromophenol, p-bromophenol,
4-hydroxybenzophenone and the like, which may be used alone or in combination of two or more.

Further, a branching agent may be used in combination as long as the effects of the present invention are not impaired. 1,1,1-Tris as branching agent
(4-hydroxyphenyl) ethane, α, α ', α''-tris
(4-hydroxyphenyl) -1,3,5-triisopropylbenzene, 1- [α-methyl-α- (4′hydroxyphenyl) ethyl] -4- [α ′, α′-bis (4 ''- Compounds having three or more functional groups such as [hydroxyphenyl) ethyl] benzenephloroglucin, trimellitic acid, and isatin bis (o-cresol) are suitable.

(3) Resin composition The visor of the helmet of the present invention is an aromatic polycarbonate resin containing the polyorganosiloxane block of the above (1) or an aromatic polycarbonate not containing a block of the resin (1) and the polyorganosiloxane. It is formed of a resin composition comprising a mixture with the resin (2). The mixture is
Even if it is blended by a kneader, it can be dry blended.

The polyorganosiloxane content of the resin composition, including the case where the above mixture is used, is usually 0.1 to 10% by weight, preferably 0.3 to 10% by weight.
It is 8% by weight, more preferably 0.5 to 6% by weight. If the polyorganosiloxane content is less than 0.1% by weight, the impact resistance is reduced, and if an impact is applied to the helmet, the visor may crack. If it exceeds 10% by weight, the rigidity is reduced.

The viscosity average molecular weight (Mv) of the resin composition is usually 10,000 to 40,000, preferably 150.
00 to 35000, more preferably 17000 to
30,000. Viscosity average molecular weight (Mv) of 1000
If it is less than 0, the impact resistance is reduced, and if an impact is applied to the helmet, the visor may be cracked. If it exceeds 40,000, the fluidity decreases and molding is difficult.

Further, various additives such as an antioxidant, a release agent, a weathering agent, an ultraviolet ray inhibitor, a coloring agent and the like may be blended as long as the effects of the present invention are not impaired. In particular, since the helmet is used outdoors and is exposed to direct sunlight, it is preferable to add a weathering agent. Further, in terms of appearance, transparent coloring according to the color of the helmet body is preferred, so that it is preferable to add a coloring agent.

(4) Helmet molding (4-1) Helmet visor Since the helmet visor requires transparency, it is molded as a separate part from the opaque helmet body. Using the resin composition, usually molded by an injection molding method, the shape and the like as a visor is not particularly limited, but it is also possible to insert the visor in a mold in advance to perform helmet molding. Well, then,
In order to have an anchor effect on the edge of the visor (the surface in contact with the helmet body), it is preferable to provide a projection (FIG. 1).

The helmet body may be combined with the helmet body by screwing, ultrasonic welding, or the like after molding the helmet body. (4-2) Helmet main body The opaque helmet main body is usually made of a coloring agent and various additives (for example, an antioxidant, a mold release agent) in the above-mentioned aromatic polycarbonate resin or ABS resin not containing the block of polyorganosiloxane. , A weathering agent, a UV inhibitor, a coloring agent, etc.) and can be molded by an injection molding method.

The reason why the helmet body is made opaque is generally for the reason of appearance, and also for consideration of using a material having good reflectivity to protect the head from direct sunlight. Therefore, for example, a colorant in which various pigments are blended based on a white pigment is usually used in an amount of 0.05 to 2 parts by weight based on 100 parts by weight of the aromatic polycarbonate resin. At the time of this injection molding, it is also effective to use an insert molding method in which the above-mentioned visor molded product is previously loaded in a mold and then injection molded.

(5) Helmet with Transparent Visor While having the inherently high safety function of the helmet, a wide field of view can be ensured, and particularly, a riding helmet for motorcycles, mopeds, bicycles, car racing, etc. It can be used as a work safety helmet, a sports helmet for baseball, skiing, skating, ice hockey, roller skating, and the like.

[0041]

The present invention will be described below in more detail with reference to Examples and Comparative Examples. [Production Example 1] Production of PC oligomer 60 liters of 400 liter of 5% sodium hydroxide aqueous solution
g of bisphenol A was dissolved to prepare an aqueous solution of bisphenol A in sodium hydroxide. Then, the sodium hydroxide aqueous solution of bisphenol A kept at room temperature was introduced at a flow rate of 138 liters / hour and methylene chloride at a flow rate of 69 liters / hour through an orifice plate into a tubular reactor having an inner diameter of 10 mm and a length of 10 m. Then, phosgene was blown in parallel at a flow rate of 10.7 kg / hour, and reacted continuously for 3 hours. The tubular reactor used here was a double tube, and the outlet temperature of the reaction solution was kept at 25 ° C. by passing cooling water through the jacket. Also,
The pH of the effluent was adjusted to indicate 10-11. By leaving the reaction solution thus obtained, the aqueous phase was separated and removed, and the methylene chloride phase (220 liters) was collected to obtain the desired PC oligomer.

Production Example 2 Synthesis of Reactive PDMS 1483 g of octamethylcyclotetrasiloxane, 9
6 g of 1,1,3,3-tetramethyldisiloxane and 35 g of 86% sulfuric acid were mixed and stirred at room temperature for 17 hours. Thereafter, the oil phase was separated, 25 g of sodium hydrogen carbonate was added, and
Stirred for hours. The mixture was filtered and vacuum distilled at 150 ° C. and 3 torr to remove low-boiling substances. 2-allylphenol and 0 of 60 g 0014G platinum chloride _-. To a mixture of platinum as alcoholate complex was added the oil obtained above in 294g at a temperature of 90 ° C.. This mixture is mixed with 90-11
The mixture was stirred for 3 hours while maintaining the temperature at 5 ° C. The product was extracted with methylene chloride and washed three times with 80% aqueous methanol to remove excess 2-allylphenol. The product was dried over anhydrous sodium sulphate and evaporated in vacuo to a temperature of 115 ° C. The obtained terminal phenol PDMS
By NMR measurement, the number of dimethylsilanooxy units was 30.

[Production Example 3-1] Production of PC-PDMS copolymer A 48 g of the reactive PDMS obtained in Production Example 2 was dissolved in 2 L of methylene chloride and mixed with 10 L of the PC oligomer obtained in Production Example 1. . A solution of 26 g of sodium hydroxide in 1 liter of water and 5.7 cc of triethylamine were added thereto, followed by stirring at 500 rpm for 1 hour at room temperature. Thereafter, bisphenol A600 dissolved in 5 liters of a 5.2 wt% aqueous sodium hydroxide solution, 8 liters of methylene chloride and p-tert
-Butylphenol (77.6 g) was added, and the mixture was stirred at 500 rpm for 1 hour at room temperature. Then, methylene chloride 5
Liter and 5 liters of water were added and the mixture was stirred at room temperature at 500 rpm for 10 minutes. After the stirring was stopped, the mixture was allowed to stand and separated to obtain an organic phase. The organic phase was washed with 5 liters of a 0.03 N aqueous sodium hydroxide solution in alkali, washed with 5 liters of 0.2 N hydrochloric acid in an acid and washed with 5 liters of water (twice) to remove methylene chloride. PC-
A PDMS copolymer was obtained.

[Production Example 3-2] Production of PC-PDMS copolymer B In Production Example 3-1, 48 g of reactive PDMS was added to 100
g to 97.6 g of p-tert-butylphenol.
Except having changed to 6.0 g, it carried out similarly to manufacture example 3-1.

Production Example 4-1 Production of Polycarbonate Resin C 64.6 g of p-tert-butylphenol was dissolved in 10.0 liters of the PC oligomer obtained in Production Example 1. Thereto were added 8 liters of methylene chloride, an aqueous sodium hydroxide solution of bisphenol A (800 g of bisphenol A, 420 g of NaOH, 6.55 liters of water) and 1.17 cc of triethylamine.
The mixture was stirred at room temperature at 00 rpm for 1 hour.

Thereafter, 5 l of methylene chloride and 5 l of water were added, and the mixture was stirred at 500 rpm for 10 minutes at room temperature. After the stirring was stopped, the mixture was allowed to stand and separated to obtain an organic phase. The organic phase was treated with a 0.03 N aqueous sodium hydroxide solution 5
The resultant was sequentially washed with 2 liters of alkali, washed with 5 liters of 0.2 N hydrochloric acid, and washed with water (twice) with 5 liters of water to remove methylene chloride to obtain flake polycarbonate.

[Production Example 4-2] Polycarbonate resin D
Production was carried out in the same manner as in Production Example 4-1 except that 64.6 g of p-tert-butylphenol was changed to 77.5 g in Production Example 4-1. PC-PDM obtained in Production Examples 3 and 4
Table 1 shows the viscosity average molecular weight (Mv) and PDMS content of the S copolymer and the polycarbonate resin.

[0048]

[Table 1]

PDMS content: PDMS content is ¹ HN
The MR ratio was determined by the intensity ratio of the peak of the isopropyl methyl group of bisphenol A at 1.7 ppm to the peak of the methyl group of dimethylsiloxane at 0.2 ppm. Mv: The intrinsic viscosity [η] of the methylene chloride solution at 20 ° C. was measured with an Ubbelohde type viscosity tube, and calculated by the following relational expression. [Η] = 1.23 × 10 ⁻⁵ · Mv ^0.83

[Examples 1-3, Comparative Examples 1-2] The obtained PC-PDMS copolymer and polycarbonate resin were dry-blended at the ratio shown in Table 2 and extruded at 280 ° C.
Pelletized. 200 ppm of tris (nonylphenyl) phosphite was blended as an antioxidant.

[0051]

[Table 2]

Using the pellets, a visor for helmet (thickness: 2 mm) was injection-molded at 300 ° C. The obtained visor is inserted into a helmet molding die in advance, and
To form a helmet having an average thickness of 3.2 mm. The material of the helmet is Teflon A25 manufactured by Idemitsu Petrochemical Co., Ltd.
00C (white colored product, Mv: 25000) was used. Put the hammock on the obtained helmet with visor and put 2 inside
A human model of kg was put in, a helmet was placed sideways from a height of 1 m, and the visor was dropped so that the visor was facing down, and cracking of the visor was evaluated. Each of the ten helmets was evaluated, and the number that did not break is shown in Table 3.

[0053]

[Table 3]

[0054]

According to the present invention, there is provided a helmet with a transparent visor in which a visor molded using a resin composition containing a specific polycarbonate-polyorganosiloxane copolymer of the present invention contains a polycarbonate-polyorganosiloxane copolymer. Compared to a helmet formed of a non-aromatic polycarbonate resin, a helmet having excellent impact resistance was found in a real drop test.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of joining a transparent visor to a main body used in the present invention.

[Explanation of symbols]

 1: Visor 2: Helmet body

Claims (2)

[Claims] 1. A helmet in which a transparent visor is joined to an opaque main body portion, wherein the visor does not contain an aromatic polycarbonate resin (A) containing a block of polyorganosiloxane or a block of the resin (A) and a polyorganosiloxane. A mixture of the aromatic polycarbonate resin (B) having a polyorganosiloxane content of 0.1%.
A helmet with a transparent visor molded using 1 to 10% by weight. 2. The helmet with a transparent visor according to claim 1, wherein the repeating unit of the polyorganosiloxane is represented by the formula (I). Embedded image [R ^a and R ^b are an alkyl group having 1 to 6 carbon atoms or a phenyl group, which may be the same or different. ]