JP3036305B2 - Coloring structure having reflection and interference effects - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel coloring structure which develops color by reflection and interference of natural light, and more particularly to a coloring fiber or chip (small piece) used for fabrics and coatings.
It is about.

[0002]

2. Description of the Related Art In recent years, automotive coatings have been
In addition to the conventional metallic coating using aluminum flake glitter, mica flakes, processed mica flakes or carbon fiber chips are used as glitter, giving anisotropic properties to improve the texture of the painted surface in combination with pigments. Trying to express. In addition, the material and color tone of interior fabrics and the like are regarded as very important in improving the texture. However, in the former, although the glittering material has an effect on the color tone, the main factor is the paint containing the pigment, and the paint is deteriorated and faded by ultraviolet rays, infrared rays, or the like, so that the color tone is significantly impaired. In the latter case as well, the same deterioration and fading of dyes and pigments as described above cannot be avoided at present. In order to solve the above problems, a structure that does not use pigments such as dyes and pigments, and develops color by reflection of natural light, interference effect, or a deeper and more vivid color by combining that effect with dyes and pigments The body has been studied diligently. For example,
In the invention described in Japanese Patent No. 14185, a composite fiber that emits pearl luster by forming a coated composite fiber composed of two or more resins having different refractive indices is described. In addition, "Textile Machinery Society Journal Vol. 42, No.
2, p. 55, and Vol. 42, No. 10, p.
0, 1989 ", a material that develops a color by forming a polarizing film into a sandwich structure with a molecular orientation anisotropic film has also been disclosed. Also, Japanese Unexamined Patent Publication No.
No. 2,280,42, Japanese Patent Publication No. 60-24847, Japanese Patent Publication No. 63-64535, etc., based on the color development of morpho butterflies from South America, without the use of ordinary pigments or dyes to interfere with light. Some have been proposed that develop color. Further, Japanese Patent Application Laid-Open No. Sho 62-170510 describes a structure that emits interference colors by providing a slit having a fixed width on the fiber surface.

[0003]

However, in the case of using the above-mentioned polarizing film, it is difficult to form fine fibers or fine chips, and it is difficult to control the principal wavelength to be reflected. Is not practical. Further, the above-mentioned JP-A-59-228042,
In JP-B-60-24847 and JP-B-63-64535 and JP-A-62-170510, the specifications of the structure (thickness and length of the shape, refractive index of constituent materials, etc.) are ambiguous. Therefore, it was difficult to obtain a desired coloring structure as it was.

In view of the above-mentioned problems, the present inventors have already filed a patent application for a novel color structure having a vivid color tone, which has not been obtained by the prior art, and which does not change with time (Japanese Patent Application No. Hei.
No. 172926). However, the above-described coloring structure has a shape with fine projections (convex wings) of μm or less to about several μm, and has a structure in which an air layer enters between the projections, and is extremely fine and complicated. Therefore, there remains a problem of manufacturing accuracy. That is, in order to actually manufacture a structure having such a cross-section, a nozzle having a core (required cross-sectional shape) and a sheath having a size several hundred times larger than the cross-sectional structure to be finally obtained is double-spun. Put in different molten polymer materials in the core and the sheath, inject, cool, and stretch to reduce to the required size, and then have high solubility for the sheath material By treating with a solvent and leaving only the core, a structure having a cross-sectional shape of a desired size is obtained. Therefore, a step of removing the polymer in the sheath by a solvent treatment or the like is required. At this time, there is a high possibility that the fine convex wings and the core will be violated, or the polymer in the sheath will remain and adhere. This means that two factors important for inducing the reflection and interference effects of natural light, that is, the accuracy of the refractive index and thickness of the constituent material cannot always be sufficiently ensured. In particular, it is extremely difficult to stably obtain an air layer (optical refractive index: n = 1.0) having a thickness of μm or less.

The present invention has been made in view of such circumstances, and has been filed by the present inventors (Japanese Patent Application No. 4-172).
No. 926) is further improved and developed, and it is an object of the present invention to provide a coloring structure having a reflection and interference effect, which is easy to manufacture, and which can surely and stably obtain a vivid color tone at a desired wavelength. .

[0006]

Means for Solving the Problems In order to achieve the above object, the present invention is configured as described in the claims. That is, according to the first aspect of the present invention, a high molecular substance that does not contain an impurity that increases the refractive index
Of two types of high molecular substances with different optical refractive indices
It has a structure in which layers are continuously and alternately stacked almost to the end of the layer.
And the width or diameter of the cross section is up to down
Of natural light, which can be reflected and reflected by natural light.
It is configured to emit a color having a wavelength in the visual ray region .
Further, in claim 2, the fibrous material according to claim 1
A minute chip is formed from the coloring structure. Further, the invention according to claim 3 is a microscopic device according to claim 2.
Apply using a transparent paint that uses the chip as a colored luminous material
Forming a colored coating film that has reflection and interference effects
It is configured as follows.

[0007]

According to the present invention, a laminated structure having a different optical refractive index is used.
Reflection and interference of natural light
It can emit brilliant colors and uses an air space.
There is no need to remove the sheath during manufacturing,
It is easy to manufacture and easily achieves the desired shape and dimensions.
You can do it. Bright colors at the desired wavelength
Can be obtained reliably and stably, and easily thin
It is suitable for practical use because it can be processed into fibrous form. In addition,
A fibrous coloring structure as described in claim 2 or claim 3.
When a chip is formed from
Is used as a brilliant coloring material for paints for vehicle body coating.
As a lower layer of protective glaze layer when painting a car body using paint
If applied, beautiful colors can be realized.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of an embodiment of the coloring structure of the present invention. In Fig 1, 1 is a first material layer, 2 is the second material layer. These material layers are made of, for example, a thin film of a polymer resin, and have different optical refractive indices. Also, the structure of FIG. 1 shows, for example, a cross section of a yarn, and FIG.
(A) those cross-sectional shape of a rectangle, (b) what is the cross-sectional shape of a circle, indicating the (c) also the the cross-sectional shape of an oval. Figure
As shown in FIG. 1, the structure of the present embodiment has a layered structure composed of alternately laminated two types of substances having different optical refractive indexes. The above-mentioned substance is, for example, a polymer resin, particularly a thermoplastic resin, and has a certain degree of visible light transmittance. For example, polyester, polyacrylonitrile, polystyrene, nylon, polypropylene, polyvinyl alcohol, polycarbonate, polymethyl methacrylate, polyether ether ketone, polyparaphenylene terephthalamide, polyphenylene sulfide, and the like. Two types of resins are selected according to the application. Note that these are merely examples, and the constituent substances of the present invention are not limited by these. In addition, the aforementioned “layered”
Is that two types of material layers are alternately and regularly laminated with _a certain thickness (d _a , d _b ) in the vertical (y) direction of the cross section of the structure, and moreover, in the horizontal (x) direction. Which has a length of Therefore, vertical incidence of natural light on the structure means that light is incident on the material layer from the vertical direction as shown in FIG.

By the way, the first material layer 1 (optical refractive index n _a ) and the second material layer 2
There are two ways of alternately stacking (optical refractive index n _b ). That is, the first is a stack of material layer 1 / material layer 2 / material layer 1 / material layer 2... From the surface layer, and the second is a stack of material layer 2 / material layer 1 / material layer 2 / material layer 1. This is the case. As will be described later, in the structure of the present invention, saturation and lightness are basically used as hue indexes, and from this viewpoint, the number of layers is necessarily several. Therefore, even if either of the above two types of alternate laminations is used, no large difference finally occurs. However, in order to reduce reflection at the surface layer, it is preferable to use a low refractive index material (first material layer 1: optical refraction). is desirable the rate n _a) bring to the surface. FIG.
The example illustrates the case in which the second material layer 2 on the surface layer. Further, the lateral (x) direction of the cross section, the long material layer regular, but may be a continuous form (e.g., the shape of FIG. 1) is a also a discontinuous shape, manufacturing and effects it is not preferable from the viewpoint of continuous form. There is no particular limitation on the outer shape of the cross section. However, in the case of using a fiber of a more vivid color (for example, a woven fabric or a knitted fabric), natural light is likely to be vertically incident in the horizontal (x) direction of the fiber cross section. It is preferable to have a flat cross-sectional shape (for example, FIGS. 1A and 1C ) .

Next, according to the present inventor's consideration, in order to achieve the intended object in the present invention, the first material layer 1 is required.
The optical refractive index n _a of the thickness d _a, the second material layer 2 of the optical refractive index n _b, its thickness when a d _b, is the following relationship between them It turned out to be necessary. That is, assuming normal incidence in the above specifications, the reflection peak wavelength λ
Although is given by _{λ = 2 (n a d a} + n b d b), this time, a _{1.3 ≦ n a 1.1 ≦ n b} / n a ≦ 1.4, and the material layer thickness is d _a, variation of d _b, that is, the maximum value of the manufacturing error of the reference value in the thickness of both material layer is 40% or less, it is necessary.

Hereinafter, the above conditions will be described. First, the one of the optical refractive index was 1.3 ≦ n _a is the optical refractive index of the polymer resin is generally 1.30 to 1.82, in general at a level of from 1.35 to 1.75 This is because 1.3 corresponds to the lower limit of the optical refractive index of the polymer resin. Note that N
It is possible to make low-refractive-index crystals such as aF or MgF ₂ into fine particles and to include them in the polymer resin to make the molecular weight 1.3 or less. However, it becomes cloudy or impairs moldability. is not. At present, as a high refractive index (1.4 or less) polymer substance, a fluororesin such as ethylene tetrafluoride (PTFE) or ethylene tetrafluoride / hexafluoropolypropylene (FEP) is used. As a polymer substance having a refractive index (1.65 or more), polyvinylidene chloride (PVD)
C), polyvinylidene fluoride (PVDF), polyesters, polyphenylene sulfide (PPS) and the like.

Next, the relationship of 1.1 ≦ n _b / n _a ≦ 1.4 indicates the optical refractive index ratio n _b / n _a of both. Regarding the importance of this relationship 1.1 ≦ n _b / n _a ≦ 1.4,
It is described below. 2 to 4 are reflection spectrum diagrams of the structure as described above, and the reflection peak wavelength λ = 0.
The relation between the wavelength λ and the reflectance when the optical refractive index ratio n _b / na is 53 μm and the optical refractive index ratio n _b / na is used as _a parameter is shown. In addition,
FIG. 2 shows that the number N of the first material layer 1 and the second material layer 2 is five.
3 shows the case of seven layers, and FIG. 4 shows the case of ten layers. Note that the number N of layers is counted as N = 1 with one first material layer and one second material layer. Therefore, all the embodiments in FIG. 1 correspond to an example in which N = 10 layers. It is difficult to clearly define how much the reflectance is beautiful in color, but it is generally considered that 50% or less is insufficient. First,
As shown in FIG. 2 , when the number of layers N = 5, n in FIG.
_b / n _a = 1.1 in the reflectance is very low and about 20%, but brighter beyond the 50% reflectance becomes n _b / n _a = 1.2 in (b). Further, as shown in FIG. 4 , the number of layers N =
In the case of 10, the reflectance exceeds 50% even if n _b / n _a = 1.1 in (a). That is, it is possible to increase the reflectance by increasing the optical refractive index ratio n _b / n _a or increasing the number N of layers.

On the other hand, instead of reflectance, chroma (C: C) and lightness (Value:
FIG. 5 shows an example of the characteristic represented by V). Figure 5 shows the relationship between the optical refractive index ratio n _b / n _a and lightness and saturation in the case where the reflection peak wavelength lambda = 0.53 .mu.m,
(A) shows the case where the number of layers N = 5, (b) shows the case where the number of layers N = 7, and (c) shows the case where the number of layers N = 10. As is apparent from an actual Munsell color chart, it is known that the color tone is relatively bright and bright at a saturation of 5 or more and a lightness of 4 or more, though slightly different depending on the hue. Therefore, according to this index, the optical refractive index ratio n _b / n _a = 1.1 to 1.4.
By increasing the number of alternately laminated layers, it is possible to obtain a sufficiently vivid color.

When the optical refractive index ratio n _b / n _a is 1.1 or less, the following problem occurs. First,
In addition, as is clear from the characteristics of FIGS. 2 to 4 , in order to obtain a high reflectance when the optical refractive index ratio is small, it is necessary to increase the number N of layers. Requires a special die (for example, in a known multi-layer parallel composite spinning) in production, and the practical limit is about 10 layers. Therefore, practically necessary reflectance (for example, 50%)
In order to obtain, the optical refractive index ratio cannot be made too small. Second, when the first material layer and the second material layer have similar optical refractive indices, the refractive index distribution at the layer boundary becomes ambiguous when the material layers are fused and bonded. Therefore, both the optical refractive index ratio n _b / n _a is 1.1 or more, it is desirable that preferably 1.2 or more. However
And as you can see from the previous explanation,
Then, even if the optical refractive index ratio n _b / n _a is smaller than the above value,
The required reflectance and vivid color can also be obtained. On the other hand, inorganic fillers and pigments such as titanium oxide (n
= 2.8), an oxide such as chromium oxide (n = 2.5), and a sulfide such as cadmium sulfide (n = 2.4) to increase the refractive index of the polymer resin (1. 80 or more), but transparency may be impaired, or the inclusion may be absorbed. In addition, it is not suitable because a problem such as impairing moldability occurs in manufacturing. Therefore, since the upper limit of the optical refractive index of the polymer resin is about 1.82,
The As of, 1.3 ≦ n if _a, the optical refractive index ratio n _b
The upper limit of / n _a is n _b / n _a ≦ 1.4.

Next, the variation (variation) in the thickness of the first material layer 1 and the second material layer 2 naturally has a great influence on the color. Figure 6 is a thickness d _a of the first and second material layers, the variation of d _b [delta] (variation from the respective set reference value), the saturation (Chroma: C) and brightness (Valu
e: V) is a characteristic diagram showing the relationship with V). This characteristic is such that the reflection peak wavelength λ = 0.53 μm and the optical refractive index ratio n _b / n _a
= 1.3, the number of layers N = 5, and the optical thickness of both layers (optical refractive index × geometric thickness, ie n _a d _a and n
_b d _b) is the characteristics when _{(n a d a = n b} d b) equal.
As is clear from FIG. 6 , the saturation is 5 or more and the lightness is 4 or more as indices up to a variation of 40%, but the variation is 40%.
It can be seen that when the value exceeds, the value of saturation becomes small and cannot be put to practical use.

Next, the range in which the thicknesses of the first material layer 1 and the second material layer 2 can be taken will be described. The first material layer 1 and the second material layer 2 thickness d _a, d _b is equation gives a reflection peak _{wavelength: λ = 2 (n a d} a + n b d b) in the range satisfying the It can be set arbitrarily. If variations the above _{equation, λ = 2 (n a d} a + n b d b) = 2n a _{[d a + d b (n b} / n
_a )]. Therefore, by determining a desired reflection peak wavelength λ of the first optical refractive index n _a and the optical refractive index of the material layer 1 ratio n _b / n _a, in the range satisfying the above equation, the first material layer 1
And a second thickness d _a of the material layer 2, d _b arbitrarily that can be set. For example, if the desired wavelength is λ = 0.53 μm
, The optical refractive index ratio n _b / n _a = 1.3, n _a = 1.3.
And then, by setting one of the material layers 2 a thickness d _b on 0.02 [mu] m, the thickness d _a of the other material layer _{1, d a = (λ /} 2n a) -d b (n b / n _a ) = 0.53 / (2 × 1.3) −0.02 × 1.3 = 0.178 μm Similarly, by setting the d _a first, d _b from the value
Can be requested. Examples of the above, FIG an example of the relationship between the second material layer 2 thickness d _b and saturation C and lightness V
FIG . This characteristic is such that the reflection peak wavelength λ = 0.53 μm
m, the optical refractive index ratio _{n b / n a = 1.3,} n a = 1.3, the relationship between the second material layer 2 thickness d _b and lightness and saturation in the case of the number of layers N = 5 Is shown. As seen from FIG. 7, the chroma C and lightness V is indicative be varied thickness d _b from 0.02μm to about 0.14μm seen to satisfactory. The first material layer 1 and the second material layer 2
The thickness d _a, d _b, and optionally can be set in a range satisfying a predetermined formula as described above, but specifically, preferably 0.016μm ≦ d _a ≦ 0.44μm 0.016μm ≦ d _b is desirable. As a matter of course, when the optical thickness of the two are equal, _{i.e., λ / 4 = n a d} a = n b
It is best when _db (at a quarter wavelength).

Hereinafter, specific examples of the present invention will be described.
This does not limit the present invention. (Example 1) In order to produce a vivid color-developing structure that reflects and interferes at a wavelength λ = 0.53 µm, a polymer resin having an optical refractive index ratio n _b / n _aよ う 1.3 is prepared as follows. Was selected. First,
Polyvinylidene fluoride (PVDF) which is a polymer resin having _a low refractive index (n _a = 1.41) is used as the first material layer 1, and _a high refractive index (n _b = 1) is used as the second material layer 2. .82), a polymer resin of polyphenylene sulfide (PP
S) was used. Therefore, the optical refractive index ratio n in this case
_b / n _a is about 1.29. Chips of the two resins were prepared, and alternately laminated flat fibers having the number of layers N = 7 and a flatness of 3.5 were produced by a known multilayer parallel spinning method. However, the first
The thickness of the material layer 1 and the thickness of the second material layer 2 are 0.1 μm and 0.08 μm, respectively, so as to be λ / 4. The spinning conditions are as follows: nozzle temperature: 330 ° C., number of filaments: 1,
The take-up speed was 250 m / min, and the cooling and solidification after spinning was natural air cooling. The reflection spectrum of the obtained alternately laminated flat fibers was evaluated using a microspectrophotometer (Model U-6000: Hitachi, Ltd.) at 0 ° incidence / 0 ° light reception. The reflectance is based on a standard white plate. As a result, as shown in FIG. 3 (c), a wavelength λ = 0.53μ
A high reflectance spectrum reaching a reflectance of about 90% near m was obtained. Further, as shown in FIG. 5 (c), the value of the chroma C and lightness V also each an extent 14, 9, far exceeding the index value of the color. In addition, there was a characteristic that the color changed depending on the viewing direction. In the above-mentioned manufacturing process, for example, a yarn having a diameter of about 10 μm is obtained. Then, a plurality of the yarns are twisted into a fibrous form and spun to obtain a woven fabric. Further, the yarn obtained in the above process is subjected to a freezing treatment and crushed to obtain a chip having a size of, for example, about 10 μm cubic. If this chip is used as a brilliant coloring material for paints for vehicle body coating, it is applied as a clear layer ( lower layer of the protective glazing layer on the top layer ) at the time of vehicle body coating using a transparent paint to achieve beautiful colors. Can do it.

[0018]

[0019]

As described above, according to the present invention, it is possible to emit a vivid color tone which has never been seen before, and since the air layer is not used as in the prior application filed by the present inventors, the present invention can be used in manufacturing. It is not necessary to remove the sheath portion, and the production becomes very easy, and the desired shape and dimensions can be easily realized. Therefore, it is possible to reliably and stably obtain a vivid color tone at a desired wavelength, and it is possible to easily process it into a fine fiber or fine chip, so that an excellent effect that is suitable for practical use is obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 shows the relationship between wavelength and reflectance when the number of layers is N = 5.
FIG. 4 is a reflection spectrum characteristic diagram.

FIG. 3 shows the relationship between wavelength and reflectance when the number of layers is N = 7.
FIG. 4 is a reflection spectrum characteristic diagram.

FIG. 4 shows the relationship between wavelength and reflectance when the number of layers is N = 10.
FIG.

FIG. 5 shows a case where the reflection peak wavelength λ is 0.53 μm.
The relationship between the optical refractive index ratio n _b / n _a and lightness and saturation is shown.
Characteristic diagram.

[6] The thickness d _a of the first and second material layers, the variation of d _b
δ (variation from each set reference value), saturation and
FIG. 6 is a characteristic diagram showing a relationship between the brightness and the brightness.

FIG. 7 shows the thickness _db , the saturation C, and the brightness of the second material layer 2.
FIG. 4 is a characteristic diagram showing a relationship with V.

[Explanation of symbols]

1. First material layer (optical refractive index n _a , thickness d _a ) 2. Second material layer (optical refractive index n _b , thickness d _b )

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-295804 (JP, A) JP-A-56-99307 (JP, A) JP-A-1-172779 (JP, A) JP-A-2- 32170 (JP, A) JP-B-46-28972 (JP, B1) US Patent 3,711,176 (US, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D01F 8/00-8/18 D01D 5/32 C09D 201/00 D06Q 1/00-1/14 G02B 5/28

Claims (3)

(57) [Claims] 1. The method of claim 1 , further comprising the steps of:
Polymer materials with different optical refractive indexes
Is continuously and alternately laminated to almost the end of the laminated part.
And the width or diameter of the cross section is up to down
It is a fibrous shape of natural
A coloring structure having a reflection and interference effect, which emits a color having a wavelength in a visible light region . 2. A fibrous coloring structure according to claim 1.
A coloring structure having reflection and interference effects, wherein a minute chip is formed . 3. The micro chip according to claim 2 is colored and radiated.
Reflection by applying using a transparent paint made as a material,
A coloring structure, wherein a coloring film having an interference action is formed .