The present invention relates to light-transmitting knitted sheet materials used for blinds and shades installed in rooms and cars, and methods for manufacturing the same.
The above-mentioned blinds and shades are installed to block outside light entering rooms or cars. Depending on the purpose, various materials, such as metal plates, resin plates, and fabrics are used for light-shielding members. Among those, fabrics including wovens and knits can be used as interior design products, whereby various types of fabrics have been proposed. For example, Patent Document 1 discloses that a three-dimensional knit fabric having honeycomb-like gaps is used for a corrugated screen of a vertical blind. Patent Document 2 discloses a double-layer curtain fabric in which a front knitted fabric and a back knitted fabric are connected by a connecting yarn so as to form a plush layer formed of a plush portion of the connecting yarn between the front knitted fabric and the back knitted fabric. Patent Document 3 discloses that a plurality of yarn rows having a length capable of holding a pair of fabrics with a predetermined distance therebetween are provided, and the yarn rows include multiple rows of yarn woven into a base fabric, which are and arranged in a sheet-like structure. Patent Document 4 discloses a knitted fabric for blinds in which front and back knitting structures are knitted from chain stitch yarns and insertion yarns such that a predetermined distance is maintained therebetween and a knitted portion formed by obliquely passing another yarn is formed between the front and the back.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 9-228764
[Patent Document 2] Japanese Unexamined Patent Application Publication No. 2001-172841
[Patent Document 3] Japanese Unexamined Patent Application Publication No. 2002-54050
[Patent Document 4] Japanese Examined Utility Model Registration Application Publication No. 7-2633
In the above-described Patent Documents, light-shielding portions are formed of woven or knitted structures from yarns. However, if the light-shielding portion is formed so as not to transmit light, as in Patent Document 4, it has to be folded every time outside light is let into the room. Thus, it is not efficient from the standpoint of usability. In Patent Documents 2 and 3, the light-shielding portions are configured to be movable and, when outside light is let into the room, the movable portions are rotated in a direction in which they are opened. However, because they are made of fabric, there is a problem in that, if the widths increase, the central portions slacken and there is a problem in durability in that, if they are repeatedly rotated, the movable portions are damaged. In Patent Document 1, the amount of transmitted light can be adjusted by the angle of the three-dimensional knit fabric. However, because the light enters through the honeycomb-like gaps, it is difficult to let sufficient amount of light in. In Patent Document 4, although the insertion yarn guided in the weft direction is knitted in the chain stitch rows of the front side knitting structure, such an insertion yarn is not knitted in the back side knitting structure. Thus, the entire knitted fabric is low in strength and is easily deformed, causing variations in the amount of transmitted light.
In view of the foregoing, an object of the present invention is to provide a light-transmitting sheet material capable of transmitting sufficient amount of light and providing high blinding effect.
A light-transmitting sheet material of the present invention includes: a front fabric and a back fabric formed by arranging a plurality of stitch rows of chain stitches, knitted in a warp direction, in a weft direction at a predetermined interval and by knitting an insertion yarn alternately in adjoining stitch rows by a predetermined length; and a plurality of light-shielding layers, being formed into sheet-like structures in the warp direction by knitting a connecting yarn alternately between the stitch rows of the front and back fabrics, arranged in the weft direction. The stitch rows of the front and back fabrics opposed to each other are connected to the adjoining light-shielding layers. The light-shielding layers are formed between the stitch rows of the front and back fabrics, being opposed to each other, located at positions shifted from each other. Entire constituent yarns are fixed by resin treatment so that the front and back fabrics are held with a predetermined distance therebetween. In addition, the front and back fabrics are knitted in such a manner that a pair of the insertion yarns are passed between the adjoining stitch rows while being guided in the weft direction so as to intersect each other and are formed into a grid-like structure with the stitch rows in the warp direction and the insertion yarns in the weft direction.
A blind of the present invention includes a plurality of slats that are formed of the above-described light-transmitting sheet material and are formed into a belt-like shape in which the stitch rows extend in a longitudinal direction.
A method for producing a light-transmitting sheet material of the present invention includes: knitting a knitted fabric including a front fabric and a back fabric formed by arranging a plurality of stitch rows of chain stitches, knitted in a warp direction, in a weft direction at a predetermined interval, knitting an insertion yarn alternately in adjoining stitch rows by a predetermined length, and passing a pair of the insertion yarns between the adjoining stitch rows while guiding them in the weft direction so as to intersect each other and a plurality of light-shielding layers, being formed into sheet-like structures in the warp direction by knitting a connecting yarn alternately between the stitch rows of the front and back fabrics, arranged in the weft direction; impregnating the resulting knitted fabric with a resin material; applying tensile force in the weft direction to the knitted fabric impregnated with the resin material, thereby causing the stitch rows of the front and back fabrics to be stretched linearly in the warp direction and the insertion yarns to be stretched linearly between the adjoining stitch rows in the weft direction so as to be formed into a grid-like structure; setting the resin material while the front and back fabrics are held with a predetermined distance therebetween; and fixing and shaping entire constituent yarns of the knitted fabric such that the stitch rows of the front and back fabrics opposed to each other are connected to the adjoining light-shielding layers and such that the light-shielding layers are formed between the stitch rows of the front and back fabrics, being opposed to each other, located at positions shifted from each other.
In the above-described structure, there is nothing that blocks incident light between the stitch rows of the front and back fabrics, arranged in the weft direction at a predetermined interval, except for the thin insertion yarns. Thus, sufficient amount of light can be transmitted through the gaps therebetween. Furthermore, because the light-shielding layers are formed into sheet-like structures in the warp direction by knitting the connecting yarn alternately between the stitch rows of the front and back fabrics, the light transmitted between the stitch rows in the surface direction of the light-shielding layers is not blocked. Thus, sufficient amount of light is transmitted in the surface direction of the light-shielding layers.
In addition, because the stitch rows of the front and back fabrics opposed to each other are connected to the adjoining light-shielding layers and the light-shielding layers are formed between the stitch rows of the front and back fabrics, being opposed to each other, located at positions shifted from each other, light incident in the direction in which the stitch rows, being opposed to each other, of the front and back fabrics are opposed to each other is substantially blocked by the light-shielding layers, whereby high blinding effect can be obtained.
Moreover, because the difference in the amount of light is great between the surface direction of the light-shielding layers and the direction in which the stitch rows are opposed to each other, the brightness/darkness contrast is clearly observed depending on the angle of view, whereby an advantage as an interior design product can be obtained.
In addition, because the entire constituent yarns are fixed by resin treatment so that the front and back fabrics are held with a predetermined distance therebetween, the sheet material has no movable portions. This improves the strength and durability, and, when it is used as, for example, the slats of a blind or a sunshade for the interior of a car, no deformation or degradation occurs. Furthermore, because it has a structure in which the stitch rows of chain stitches are connected by the connecting yarn, the strength against compression and twisting in the thickness direction is improved.
Moreover, the front and back fabrics are knitted into a grid-like structure with the stitch rows in the warp direction and the insertion yarns in the weft direction by passing the pair of insertion yarns between the adjoining stitch rows while guiding them in the weft direction so as to intersect each other. Furthermore, because the insertion yarns are knitted in the stitch rows in the warp direction and the insertion yarns are passed twice in the weft direction, it is possible to improve the strength of the front and back fabrics and to further improve the shape retaining property, while ensuring the light transmission property. In addition, because the pair of insertion yarns are knitted while being guided in the weft direction so as to intersect each other, by applying tensile force in the weft direction to the entire knitted fabric so that the insertion yarns are stretched tight, the entirety of the front and back fabrics can be easily formed into a grid-like structure.
Because the blind of the present invention includes a plurality of slats that are formed of the light-transmitting sheet material and are formed into a belt-like shape in which the stitch rows extend in the longitudinal direction, it is possible to transmit light by rotating the slats about the axes extending in the longitudinal direction so that the surface direction of the light-shielding layers of the slats faces frontward, and it is possible to block light by making the direction in which the stitch rows are opposed to each other face frontward, whereby it has high blinding effect and can increase the brightness/darkness contrast by transmitting sufficient light.
Such a blind can express the magnificence and texture of thick curtains as well as the lightness and transparency of lace curtains, depending on the rotation direction of the slats formed of the light-transmitting sheet material, and can be used as a novel interior design product capable of coping with various situations.
Embodiments of the present invention will be described in detail below. Because the embodiments described below are preferred examples for embodying the present invention, various technical limitations are made. However, the present invention is not limited to those embodiments unless it is stated to be limited in the following description.
The front fabric 2 is formed into a planar shape by arranging stitch rows 20, formed in the warp direction by chain stitches, in the weft direction at a predetermined interval and knitting insertion yarns 21 alternately in the adjoining stitch rows 20 by a predetermined length. Thus, the front fabric 2 is formed in a grid-like structure with the stitch rows 20 extending linearly in the warp direction and the insertion yarns 21 arranged to pass between the adjoining stitch rows 20 while being guided in the weft direction.
Similarly, the back fabric 3 is formed into a planar shape by arranging stitch rows 30, formed in the warp direction by chain stitches, in the weft direction at a predetermined interval and knitting insertion yarns 31 alternately in the adjoining stitch rows 30 by a predetermined length. Thus, the front fabric 3 is formed in a grid-like structure with the stitch rows 30 extending linearly in the warp direction and the insertion yarns 31 arranged to pass between the adjoining stitch rows 30 while being guided in the weft direction.
The stitch rows 20 of the front fabric 2 are opposed to the stitch rows 30 of the back fabric 3 and, as shown in
The light-shielding layers 4 are formed into sheet-like structures in the warp direction by knitting the connecting yarn alternately into the stitch rows 20 of the front fabric 2 and the stitch rows 30 of the back fabric 3, and the plurality of light-shielding layers 4 are arranged in parallel in the weft direction. The connecting yarn constituting the light-shielding layers 4 is arranged closely so as to provide a light-shielding property. By using a bulky yarn, such as a crimp yarn, as the connecting yarn, the light-shielding property can be further improved.
As shown in
Reference numerals L4 and L5 denote knitting yarns for forming edges on both ends and, as will be described below, are used to fix both ends of the knitted fabric to conveyance pins to be stretched in a shaping process. A reference numeral L6 denotes the connecting yarn that is knitted alternately in the loops of the stitch rows 20 and 30.
A reference numeral L7 denotes the stitch row 30 of the back fabric 3 knitted by chain stitches, and reference numerals L8 and L9 denote the insertion yarns 31 of the back fabric 3. Similarly to the front fabric 2, L8 and L9, which are the pair of insertion yarns 31, are knitted alternately in the adjoining stitch rows 30 by a predetermined length and are passed between the adjoining stitch rows 30 so as to intersect each other.
Examples of the knitting yarn used for the front fabric 2 and the back fabric 3 include regenerated fiber such as rayon, natural fiber such as cotton, semi-synthetic fiber such as acetate, polyester synthetic fiber such as polyethylene terephthalate, aliphatic polyamide synthetic fiber such as nylon, and blend fiber of the aforementioned fibers, and may be either filament yarn or spun yarn; it is not specifically limited.
For the connecting yarn, a bulky yarn, for example, a crimp yarn composed of synthetic fiber, e.g., polyester synthetic fiber such as polyethylene terephthalate and aliphatic polyamide synthetic fiber such as nylon is desirable. The use of such yarn can improve the light-shielding property when knitted into sheet-like structures as light-shielding layers.
The impregnated knitted fabric is squeezed by squeezing rollers 101 to remove excess liquid resin, and is then conveyed into a dryer 102. In the dryer 102, the knitted fabric is dried in a stretched state by being hooked on the pins at both side edges. In a drying step, it is adequate to perform drying at 150° C. for 2 to 3 minutes. Because the knitted fabric is dried in a stretched state by being pulled at both side edges, the insertion yarns passed between the adjoining stitch rows are stretched tight, causing the stitch rows of the front and back fabrics to linearly extend in the warp direction and the insertion yarns to linearly extend in the weft direction so as to be formed into a grid-like structure, and the constituent yarns are fixed and shaped in a state in which the front and back fabrics are held with a predetermined distance therebetween.
In this example, as shown in
When knitting the knitted fabric shown in
As has been described above, by using the sheet material of the present invention for the slats of blinds, it can be used as an interior design product capable of gradually adjusting the brightness/darkness contrast by rotating the slats, capable of achieving the texture of thick curtains as well as the transparency of lace curtains, and capable of dimming or blocking light in accordance with various situations. Furthermore, by changing the angle of the light-shielding layers with respect to the surface direction of the sheet material, the light-shielding property and the light transmission property can be changed. For example, the light transmission property can be increased by increasing the angle of the light-shielding layers with respect to the surface direction, and the light-shielding property can be increased by reducing that with respect to the surface direction.
The blind 300 can also provide great brightness/darkness contrast between an open state and a closed state, and is preferable as an interior design product.
Using the double raschel machine shown in
Then, using an acrylic resin material as the liquid resin, the resin treatment shown in
The sheet material of the present invention is suitable for blinds and shades since it provides great brightness/darkness contrast between the light-shielding property and the light transmission property. For example, when it is used for a sunshade to be attached to the interior of a car, by bringing it into close contact with the inner surface of the window, light entering the car can be blocked.
Number | Date | Country | Kind |
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2007-096884 | Apr 2007 | JP | national |
2007-204807 | Aug 2007 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP2007/066144 | 8/21/2007 | WO | 00 | 10/1/2009 |
Publishing Document | Publishing Date | Country | Kind |
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WO2008/120406 | 10/9/2008 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
2142900 | Hinlein et al. | Jan 1939 | A |
2371039 | Fischel | Mar 1945 | A |
3864944 | Jackson | Feb 1975 | A |
4399671 | Henningsson | Aug 1983 | A |
4626465 | Henningsson | Dec 1986 | A |
4632863 | Henningsson | Dec 1986 | A |
4811573 | Sternlieb | Mar 1989 | A |
5613540 | Jelic | Mar 1997 | A |
5619869 | Tacy | Apr 1997 | A |
5735145 | Pernick | Apr 1998 | A |
6212913 | Weiss | Apr 2001 | B1 |
7415845 | Graichen | Aug 2008 | B1 |
7836936 | Graichen | Nov 2010 | B2 |
Number | Date | Country |
---|---|---|
56-88725 | Jul 1981 | JP |
59-47062 | Nov 1984 | JP |
6-47585 | Jun 1994 | JP |
2001-172841 | Jun 2001 | JP |
2002-54050 | Feb 2002 | JP |
Number | Date | Country | |
---|---|---|---|
20100132896 A1 | Jun 2010 | US |