JP4758566B2 - Buffer for glass substrate and package using the buffer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a transfer buffer that protects a glass substrate formed with electronic components such as a semiconductor device on a glass substrate from damage caused by vibrations during transportation, and a plurality of the glass substrates using the buffer. The present invention relates to a package packaged simultaneously.
[0002]
[Prior art]
In recent years, liquid crystal displays and plasma displays, which are one of the peripheral devices for electronic and electrical devices, especially personal computers such as mobile phones, have been produced with the development of the information technology industry represented by the Internet. There is a strong demand for the development of shock absorber-related technologies that are used for packaging and transporting devices that are growing at a rapid pace. Among them, glass substrates incorporating electronic components such as semiconductor devices, for example, color filter glass substrates and TFT glass substrates (substrates on which circuits incorporating thin film transistors are formed) and glass substrates such as liquid crystal panel substrates are thin, In addition to being susceptible to drop impacts and vibrations that occur during transportation, the structure is very fine, and it is easily affected by the outside and difficult to handle. In particular, when transporting a glass substrate before processing or a semi-finished product before becoming a final product, the electronic parts are handled in a bare state, so that they are more affected by static electricity, dust, dust, etc. There was a case where the function was impaired.
[0003]
Therefore, many packaging techniques for safely transporting glass substrates without damaging them have been proposed.
[0004]
As an example, there is a technique disclosed in JP-A-5-319456. The main point is a shock absorber made of a polyolefin bead foam having specific characteristics, in which the cross section has an L shape, and a plurality of substrate insertion grooves are provided on the inner side along the L shape. When packaging the glass substrate, a plurality of glass substrates are arranged in parallel at a predetermined interval to form a rectangular parallelepiped, and the corners of each substrate are inserted into the substrate insertion grooves of the buffer, respectively, and orthogonal to the substrate surface. The four sides of the rectangular parallelepiped are fitted with the buffer body, and further fixed with a fixing tool such as rubber or tape as necessary.
[0005]
[Problems to be solved by the invention]
However, when a fixing tool such as rubber or tape is fixed to the outside of the buffer body, the fastening force concentrates on the corners of the buffer body. In some cases, the protective function does not work sufficiently due to the removal from the insertion groove.
[0006]
Furthermore, since the outermost two of the plurality of glass substrates packed with the buffer body are open, there is also a problem that the clean glass surface is damaged or contaminated during handling operations. The two glass substrates are called non-standard products, so-called dummy substrates, and are distinguished from normal products. This dummy substrate cannot be secondary processed at the transport destination, and is extremely economical. In the glass substrate take-out operation at the time of the secondary process, the normal product and the dummy substrate that are products are distinguished from each other, At present, management is required and improvement is desired.
[0007]
In addition, the L-shaped buffer described above is formed so that the width of the substrate insertion groove is equal to or slightly narrower than the thickness of the glass substrate, and has a good elastic recovery property during compression, which is a characteristic of polyolefin bead foam. It is used to fix the glass substrate. Therefore, it is effective for dust resistance due to vibration friction with the glass substrate being transported, but when packing the glass substrate, which is the original purpose, the frictional resistance with the glass substrate has an adverse effect, which is impossible. When trying to fit the glass substrate into the substrate insertion groove, the extremely thin glass substrate of about 0.6 to 0.8 mm is easily bent and easily damaged, and it takes a long time to work carefully to avoid damage. The problem has arisen. The same applies to the removal of the glass substrate. In recent years, the introduction of glass substrate automatic storage devices and take-out devices has been progressing from the viewpoint of labor saving, but problems have occurred due to the above problems, and it is pointed out that the buffer is not suitable for automation as a real problem. There is also.
[0008]
Furthermore, there is a potential problem that when the glass substrate is inserted into the substrate insertion groove, fine scratches are generated on the glass substrate surface due to the frictional resistance.
[0009]
This aptitude for automation is a practical characteristic that is becoming more and more important with the recent increase in size of glass substrates. However, the size of the buffer has also increased, and the problem of warpage and deformation has become apparent in conventional buffers.
[0010]
In view of the above problems, the problem of the present invention is that the glass substrate groove at the L-shaped end portion of the buffer body does not slip during packaging of the glass substrate, and even if an external force such as vibration or drop impact is applied during handling or handling, the glass It is intended to provide a buffer for glass substrate that can safely protect the substrate. Furthermore, it is suitable for automation of packing and taking out of the glass substrate, and does not easily generate dust even when sliding on the glass substrate. To provide a glass substrate buffer that can be used multiple times with excellent durability, does not require a dummy glass, and is economically excellent, and provides a package that is packed using the buffer. It is in.
[0011]
[Means for Solving the Problems]
The first of the present invention is a buffer for glass substrate comprising an in-mold molded body of polyolefin resin expanded particles,
A main body provided with a plurality of substrate insertion grooves for fixing two side ends forming a corner of the glass substrate on the inner side along the L shape, the cross section having an L shape according to the shape of the corner of the glass substrate, A side wall extending in parallel with the substrate insertion groove and extending over the entire length of the L-shape, which is attached to both ends of the L-shape of the main body,
In the shape where the side wall is provided with an arc-shaped notch that is linear or outwardly convex at a corner opposite to the L-shaped corner of the rectangle having two side edges that contact the main body as a constituent side, The area exceeds 80% of the rectangular area and is 99% or less,
The average particle diameter of the expanded particles of the molded product is 1.5 to 5.0 mm, the fusion rate is 70% or more, the compression elastic index is 3.9 to 490, and the recovery rate is 60% or more. .
[0012]
In the buffer body, the maximum thickness of the main body is 10 to 100 mm, the ratio of the two L-shaped sides of the main body is 1.0 to 3.5 on the short side basis, the thickness of the side wall is 10 to 100 mm, the substrate insertion groove It is preferable that the groove width is 1.0 to 4.0 times the thickness of the glass substrate, the groove depth is 3 to 15 mm, and the groove pitch is 6 to 100 mm.
[0013]
In the second aspect of the present invention, a plurality of glass substrates are arranged in parallel at a predetermined interval to form a rectangular parallelepiped, and the corners of each substrate are inserted into the substrate insertion grooves of the glass substrate buffer according to the present invention. A package body characterized in that four sides of the rectangular parallelepiped perpendicular to the substrate surface are fitted by the buffer body, and a long fixing tool is wound and fastened to the outside of the buffer body to be fixed. It is.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
The shock absorber of the present invention is characterized in that wide side walls are attached to both side ends of an L-shaped main body having a substrate insertion groove for fixing two side ends constituting the corners of the glass substrate. Thereby, in the package using the buffer of the present invention, the surface of the outermost glass substrate is widely covered with the side wall to prevent contamination and damage, and at the same time, the L-shape of the main body is fixed by the side wall. , L-shaped spread is prevented.
[0015]
Hereinafter, embodiments of the buffer according to the present invention will be described.
[0016]
FIG. 1 is a perspective view of a preferred embodiment of a shock absorber according to the present invention, in which 1 is a shock absorber of the embodiment, 2 is a main body, 3 is a substrate insertion groove, 4 is a side wall, and 5 is a fixture. Guide grooves 6 are notches.
[0017]
The basic structure of the shock absorber of the present invention includes a main body 2 having a L-shaped cross section according to the shape of the corner of the glass substrate, and a pair of opposing side walls 4 attached to both side ends of the L-shaped main body 2. Consists of. The main body 2 is provided with a plurality of substrate insertion grooves 3 for fixing the two side ends forming the corners of the glass substrate on the inner side along the L shape, and the side walls 4 are formed in parallel to the substrate insertion grooves 3. Is done.
[0018]
The side wall 4 according to the present invention is formed over the entire length of the L-shape of the main body 2, and the shape of the side wall 4 is a rectangle whose two sides are in contact with the main body 2. This is a shape in which a notch 6 is provided at a corner opposite to the corner. The shape of the notch 6 may be a linear arc shape as shown in FIG. 1 or an outwardly convex arc shape, and its size is such that the area of the side wall 4 exceeds 80% and 99% or less of the rectangular area. Adjust.
[0019]
In FIG. 2, the perspective view of the package body which packed the glass substrate using the buffer body of FIG. 1 is shown. In the figure, 11 is a glass substrate and 12 is a fixture. As shown in FIG. 2, the buffer bodies 1 of the present invention are basically used as a set of four, and a plurality of glass substrates 11 are arranged in parallel at a predetermined interval to form a rectangular parallelepiped, and the corners of each substrate are buffered. It is inserted into the board insertion groove of the body 1 and the four sides of the rectangular parallelepiped are fitted by the buffer body 1. Then, the long fixing tool 12 is wound and fastened to the fixing tool guide groove 5 formed on the outside of the buffer body 1 and fixed. In the buffer of the present invention, the fixture guide groove 5 may be formed as necessary.
[0020]
In the shock absorber 1 of the present invention, as shown in FIG. 1, by providing the wide side wall 4 over the entire length of the L shape, the L shape is fixed by the side wall 4, and the rigidity of the shock absorber itself is increased. Because of the improvement, even if the fastening force of the fixing tool 12 acts on the corners of the L-shape in the package packed as shown in FIG. 2, the L-shape does not open and the L-shape ends. The groove of the substrate in the portion is prevented from shifting.
[0021]
Moreover, as shown in FIG. 2, since the surface of the outermost glass substrate 11 is covered with the wide side wall 4, the contamination and damage are significantly suppressed. Furthermore, since the notch 6 is formed in the diagonal part of the side wall 4 opposite to the L-shaped corner, the side wall 4 is unlikely to warp in the diagonal part, and contact with the glass substrate 11 is prevented. It is suppressed.
[0022]
The buffer of the present invention is an in-mold molded product of polyolefin resin expanded particles. The molded body is obtained by filling polyolefin resin foamable particles in a mold and then heating and foaming to expand the foamed particles and molding them into a desired shape. The mold used for the molding is injection molding Production costs are less than 1/10 even with complicated shapes compared to metal molds, and compact shaped products can be easily and efficiently mass-produced with high dimensional accuracy, making them economical and suitable for mass production. .
[0023]
Furthermore, in-mold molded products of polyolefin resin foamed particles generate very small amounts of fine dust even by rubbing against the glass substrate, and the glass substrate is extremely hardly contaminated by the dust. Further, the molded body is not easily deformed even when subjected to an external force during handling work or transportation, and even if deformed, it has excellent recovery and high dimensional stability. Further, such a buffer body is washed with pure water each time before use in repeated use, but the molded body has a small amount of water absorption and is excellent in drying property.
[0024]
The polyolefin resin used in the buffer of the present invention may be either a crosslinked type or a non-crosslinked type. Specific examples of the resin material include low, medium, high density polyethylene, linear low density polyethylene, and linear ultra-high density. Low density polyethylene, polyethylene based on metallocene catalyst, polyethylene resin typified by ethylene-vinyl acetate copolymer resin and the like, and random and block copolymers of ethylene, butene-1,4-methylpentene-1, etc. and propylene It is preferably selected from a copolymer resin or a composition containing two or more of the above.
[0025]
As a resin material particularly suitable for the present invention, the resin density is 0.927 to 0.970 g / cm.^ThreeAnd random copolymer resins of polyethylene and propylene. Resin density is 0.927 g / cm^ThreeThe above-mentioned polyethylene has an appropriate compression elastic index of the buffer described later, and hardly deforms when an external force is applied. Moreover, it is not necessary to reduce the expansion ratio of the expanded particles in order to obtain a specific compression elastic index, which is preferable from the viewpoint of light weight and economy. The resin density is 0.970 g / cm.^ThreeThe following polyethylene is preferable because it has sufficient flexibility, and dust resistance and recoverability are also appropriate. Furthermore, a random copolymer resin of propylene has a high compression elastic index, and is excellent in recoverability and durability during repeated use, and is most preferably used in the present invention.
[0026]
In the molded body constituting the buffer of the present invention, the average particle diameter of the expanded particles is 1.5 to 5.0 mm, the fusion rate is 70% or more, the compression elastic index is 3.9 to 490, and the recovery rate is 60. % Or more.
[0027]
As described above, the average particle diameter of the expanded particles is 1.5 to 5.0 mm, preferably 2.0 to 4.5 mm. When the average particle diameter of the expanded particles is 1.5 mm to 5.0 mm, the expanded particles can be filled up to a fine portion of the substrate insertion groove at the time of molding, and the mold shape and dimensional reproducibility are good. Further, since the ratio of the surface area per one (volume) of the foamed particles is small and the gas pressure (air) dissipating property in the particles is small in the steam heating process at the time of molding in the mold, sufficient foam expansion is exhibited. As a result, it is preferable because voids are unlikely to occur between the foamed particles constituting the in-mold molded body, and there is no possibility that dust will enter the voids and the cleanliness of the buffer body cannot be maintained.
[0028]
The average particle diameter of the expanded particles constituting the buffer of the present invention is the expanded particles in contact with the straight line having a length of 100 mm indicated by a ballpoint pen on the surface of the in-mold molded body. The average particle diameter C [mm] is calculated from the following formula (A). The evaluation is the average value of the values obtained from the three straight lines.
[0029]
C = (1.626 × L) / N (A)
L: Center line length [mm]
N: Number of particles
[0030]
The fusion rate of the molded body according to the present invention is the total length in the thickness direction in the fractured surface when a cut having a depth of about 1 mm is made in the thickness direction of the buffer and the cut is bent outward. And the number of foamed particles that have undergone particle destruction (material destruction) with respect to the total number of foamed particles having an area over a length of about 75 mm. In the shock absorber of the present invention, sufficient mechanical strength is obtained when the fusion rate is 70% or more, and when the fastener is fastened, the fastener bites into the shock absorber and destroys the shock absorber. Problems such as the buffer body being easily lost are less likely to occur. In addition, the problem that minute voids are generated between the foamed particles and water absorption due to capillary action is exhibited is preferable because it hardly occurs when the fusion rate is 70% or more.
[0031]
Further, when the compression elastic index of the molded body is 3.9 or more, the buffer body is not easily deformed even when an external force is applied, the durability is good, and the glass substrate size is 600 mm × 700 mm. Even if the size is larger, permanent deformation due to the weight of the glass substrate is less likely to occur, and the glass substrate can be easily fixed. Further, when the compression elastic index is 490 or less, it is not particularly necessary to reduce the foaming ratio of the buffer body, which is preferable from the viewpoint of light weight and economy. Furthermore, when the compression elastic index is in the range of 490 or less, the flexibility is good, the dust resistance is excellent, and the shock absorbing performance such as a drop impact is also excellent.
[0032]
The compression elastic index according to the present invention is the compression elastic modulus [N / cm.²] Is divided by the expansion ratio, and the compression elastic modulus is a value obtained in accordance with JIS K 7220 for the test piece measured for the following expansion ratio, and the compression speed is 10 mm / min. In addition, when the thickness of the test piece is less than 20 mm, a plurality of pieces are measured so that the thickness is about 20 mm.
[0033]
Measurement method of compression ratio: A flat test piece having a width of 50 mm, a length of 50 mm and a thickness of 20 mm was cut out from the buffer, and after measuring the weight [g] to 10 mg, the width, length and thickness were measured with a caliper. , Volume [cm^Three] And the expansion ratio E [cm] from the following formula (B)^Three/ G] is calculated.
[0034]
E = volume / weight [cm^Three/ G] (B)
[0035]
Further, when the compression elastic index is in the range of 3.9 to 490 and the recovery rate is 60% or more, the repeated durability, which is a feature of the in-mold molded product of polyolefin resin expanded particles, is good, and the frequency of use Even if it becomes high, since deformation is small, it is preferable. The recovery rate means that a flat test piece having a width of 50 mm, a length of 50 mm, and a thickness of 20 mm is cut out from the buffer, and the compression test apparatus “Autograph AG-5000D” manufactured by Shimadzu Corporation is used to obtain 10 mm / After compressing to 50% of the thickness of the test piece at a compression speed of 1 minute, immediately remove until the load becomes zero at the same speed, measure the thickness at the moment when the load becomes zero, and from the following formula (C) The recovery rate R [%] is calculated. In addition, when the thickness of the test piece is less than 20 mm, a plurality of sheets are measured so as to have a thickness of about 20 mm.
[0036]
R = (T₁/ T₀) X 100 [%] (C)
T₀: Thickness of specimen before test [mm]
T₁: Thickness of test specimen after test (when load is zero) [mm]
[0037]
Next, the external dimensions of the buffer of the present invention will be described in detail with reference to FIGS. FIG. 3 is a partial cross-sectional view in the direction orthogonal to the L-shape of the main body in the embodiment of the shock absorber of the present invention, and FIG. 4 is a side view of the embodiment of FIG. 3, 13 is a ridge that separates adjacent substrate insertion grooves 3, 22 is a bottom portion of the substrate insertion groove 3, and 23 is a top portion of the ridge 13. In FIG. 4, 21 a and 21 b are L-shapes of the main body 2. It is a buffer plate to constitute, and forms an L-shaped short side and a long side, respectively. Reference numerals 22a and 22b denote bottom portions of substrate insertion grooves formed in the buffer plates 21a and 21b, respectively, corresponding to 22 in FIG. Reference numerals 23a and 23b denote the tops of the ridges between adjacent substrate insertion grooves corresponding to 23 in FIG.
[0038]
As shown in FIG. 4, the shock absorber of the present invention has a substantially L-shaped cross section, and the maximum thickness of the shock absorbing plates 21a and 21b constituting the L shape (thickness in the ridge 13 of FIG. 3). , T₁) And the thickness of the side wall 4 depends on the size of the target glass substrate, but is preferably selected from the range of 10 to 100 mm, and more preferably 15 to 50 mm. When this thickness is within the above preferred range, the cushioning body has sufficient rigidity, hardly warps or deforms, and a sufficient L-shaped restraining force can be obtained at the side wall 4. Within the above range, the productivity of the buffer is good, the bulk of the buffer and the package is appropriate, and the economy is good. The thickness of the buffer plates 21a and 21b at the bottom portions 22a and 22b of the substrate insertion groove 3 is preferably 5 mm or more in order to obtain the above-described effects.
[0039]
Further, in the shock absorber of the present invention, the L side of the main body (t_S) And long side (t_L) Ratio relative to the short side (t_L/ T_S) Is preferably 1.0 to 3.5, and more preferably 1.0 to 3.3. When the ratio is within the above range, the balance between the long side and the short side is good, the fixing stability of the rectangular glass substrate is good, and damage due to the bending of the glass substrate is less likely to occur.
[0040]
Further, in the present invention, in order to prevent contamination and damage of the glass substrate, it is preferable that the glass substrate surface is covered as wide as possible by the side wall of the buffer, and therefore, within the range of the short side and the long side. In each case, the length of the side ends supported by the two shock absorbers at each side end of the glass substrate during packaging is preferably 50% or more, and more preferably 70% or more. When the length of the side edge of the glass substrate supported by the buffer is 50% or more, the glass substrate is less likely to be damaged even if an impact load is concentrated on the support portion when receiving a drop impact. Can be widely covered and protected, which is preferable. Furthermore, the stress applied to the buffer body is lower than that of the glass substrate, and dust generation due to contact friction due to vibration during conveyance is reduced, which is desirable from the viewpoint of cleanliness. In addition, since a slight gap is required between the two buffer bodies supporting each side end of the glass substrate, the length of the side ends supported by the two buffer bodies at each side end is 98% or less. Is preferred.
[0041]
Further, the side wall 4 of the buffer body of the present invention is preferably wide in order to cover and protect the glass substrate, and considering the provision of the notch 6, the area of the side wall 4 [rectangular area (t_aXt_bThe area obtained by subtracting the area of the region removed by the notch 6) is more than 80% and 99% or less of the rectangular area.
[0042]
As a specific external dimension, preferably, the short side (t_S) Is 100-500 mm, long side (t_L) Is 100 to 1100 mm, and the length in the direction orthogonal to the L-shape is 150 to 600 mm, although it depends on the number of packed glass substrates.
[0043]
Next, the substrate insertion groove 3 will be described with reference to FIG. In the buffer of the present invention, the groove width t of the plurality of substrate insertion grooves 3 provided in the main body 2_ThreeIs preferably 1.0 to 4.0 times the thickness of the glass substrate to be packed, more preferably 1.2 to 3.5 times. When the numerical value is 1.0 times or more, workability at the time of manual insertion and removal of the glass substrate is good, and even when automatic insertion is performed, the glass substrate is hardly damaged. In addition, at 4.0 times or less, there is no problem even if the insertion and removal of the glass substrate are automated, there is no rattling due to vibration shock during the transportation of the glass substrate, and the glass substrate is prevented from being damaged, It is preferable in terms of cleanliness because it generates less dust.
[0044]
Further, the groove depth t of the substrate insertion groove 3₂Is preferably in the range of 3 to 15 mm in view of the size and weight of the glass substrate, the compression elastic index of the molded body, and the like. The groove depth of 3 mm or more is preferable because the glass substrate is not easily detached and damaged even when it receives a vibration impact during transportation or a drop impact during handling. Also, near the side edge of the glass substrate in contact with the buffer, fine scratches are likely to occur due to rubbing due to vibration shock during transportation, and the region is cut and removed during processing of the glass substrate. It is preferable that the depth of the groove 3 is 15 mm or less because a region to be cut and removed is small. Further, dust generation due to rubbing between the glass substrate and the buffer body is reduced, which is desirable from the viewpoint of cleanliness.
[0045]
Further, the groove pitch t of the substrate insertion groove 3_FourIs preferably in the range of 6 to 100 mm in view of the type of glass substrate (for example, display constituent substrate such as mother glass and color filter glass substrate) and its size and weight, and the compression elastic index and groove width of the molded body. Just choose. In other words, it may be set so that the glass substrates are bent and the substrates do not come into contact with each other when subjected to vibration impact during conveyance or drop impact during handling.
[0046]
As shown in FIG. 3, the cross-sectional shape of the substrate insertion groove 3 provided in the buffer according to the present invention is a groove width t._ThreeMay be the same as the bottom and the opening, that is, the shape (a) in which the cross section of the ridge 13 between adjacent substrate insertion grooves is rectangular may be used. That is, the groove width is preferably widened at the opening, that is, the top cross section of the ridge 13 is upwardly convex arcuate (b) or trapezoidal (c).
[0047]
As described above, the cushioning body of the present invention is used as a set of four, and after packaging the glass substrate, a long fixing tool is wound and fastened around the periphery to form a package. As a fixture used here, what is necessary is just long things, such as string form and tape form, for example, a polypropylene tape is used preferably. Further, normally, the package is housed in a clean polyethylene bag or the like, sealed, stored and transported so that dust does not enter from the outside.
[0048]
In the embodiment of FIG. 2, an example in which the same buffer body is used as a set of four is shown. However, the present invention is not limited to this, and the size, packing, and workability of the glass substrate, particularly an automatic device, are not limited thereto. In this case, two types of buffer bodies having different sizes may be used in combination in consideration of taking out positioning and the like. For example, there is a combination in which a large size buffer is used for the bottom where the load is applied, and a small size buffer is used for the upper part. Moreover, it is not always necessary to make the short side of the buffer correspond to the short side of the glass substrate. For two buffer members that support one side of the glass substrate, one is a combination of the short side and the other is the long side. I do not care.
[0049]
Moreover, the buffer body of this invention can be used also for storage besides the use for conveyance of a glass substrate. Specifically, two buffer bodies of the present invention are fixed in pairs in an outer box such as plastic cardboard and a glass substrate is inserted. In this case, the buffer above the glass substrate may or may not be used. Moreover, the intrusion of dust is prevented using a lid as necessary.
[0050]
【Example】
The buffer body of the following specification was produced and the glass substrate was packed and evaluated.
[0051]
Example 1
[Glass substrate specifications]
Application: Mother glass for liquid crystal display
Dimensions: 850mm x 1000mm
Thickness: 0.7mm
[0052]
[Resin physical properties]
Material: Ethylene / propylene random copolymer resin
Foaming ratio: 20cm^Three/ G
Average particle size: 3.6 mm
Fusion rate: 88%
Compression elastic modulus: 559 N / cm²
Compression elastic index: 28.0
Recovery rate: 88%
[0053]
〔External dimensions〕
Number of glass substrates: 12
Body
Short side: 430mm
Long side: 460mm
Length in L-shaped orthogonal direction: 415mm
Thickness: 35mm
Side wall
Shape: Fig. 1 (Linear cutout)
Area: 85% of rectangle
Thickness: 35mm
PCB insertion groove
Groove width: 1.5mm
Groove depth: 9.5 mm
Groove pitch: 25mm
Shape: FIG. 3C, straight part height 5.0 mm, trapezoidal part height 4.5 mm
[0054]
[Evaluation 1]
The above-mentioned buffer bodies were packaged as a set of four, and the above-mentioned 12 glass substrates were packed, and a polypropylene tape was wound and fastened at two locations as a fixture to obtain a package. When this package is transported by a normal route, there is no warping or deformation at the L-shaped end of the buffer, the glass substrate has good packaging workability, and the L-shaped is maintained, and the glass substrate in the package There was no slip of the groove, and it was possible to transport stably.
[0055]
[Evaluation 2]
Furthermore, in order to evaluate the buffer performance of the buffer body of the present example, the package body of the above evaluation 1 is packed in a cardboard box (CD-4 of JIS Z 1506 standard), and a free drop test is performed under the following conditions. did.
・ Drop test conditions
Drop height: 30cm
Package drop surface: Only the ground of the package
Number of drops: 3 times
[0056]
Under the above conditions, the glass substrate was not dropped even after being dropped three times, the packaging state before the test was maintained, and the glass substrate was not damaged. Moreover, when the glass substrate surface was observed visually, adhesion of dust was not observed at all.
[0057]
[Evaluation 3]
Furthermore, in order to evaluate the glass substrate fixing performance of the buffer of the present invention, a vibration test was performed on the packaging body of Evaluation 1 under the following conditions. The vibration test was carried out in accordance with the test method of JIS Z 0232 by fixing the package to a vibration table of a vibration test apparatus.
・ Vibration test conditions
Vibration direction: Up and down
Vibration waveform: sine wave
Sweep: logarithmic sweep (frequency: 5 to 100 Hz, sweep speed: 0.5 octave / min)
Vibration acceleration: ± 0.75G
Vibration time: 30 minutes
[0058]
After the above vibration test was completed, the glass substrate was fixed in a visually fixed state, and although the glass substrate was slightly loosened, there was no glass substrate dropped out of the substrate insertion groove, and no dust adhered to the visual inspection. Not observed.
[0059]
(Comparative Example 1)
A buffer body having only the main body without the side wall of the following specifications was produced, and the glass substrate was packed for evaluation.
[0060]
[Glass substrate specifications]
Same as Example 1
[0061]
[Resin physical properties]
Material: Ethylene / propylene random copolymer resin
Foaming ratio: 20cm^Three/ G
Average particle size: 3.6 mm
Fusion rate: 86%
Compression elastic modulus: 549 N / cm²
Compression elastic index: 27.5
Recovery rate: 87%
[0062]
〔External dimensions〕
Number of glass substrates: 12
Body
Short side: 430mm
Long side: 460mm
Length in L-shaped orthogonal direction: 400mm
Thickness: 35mm
PCB insertion groove
Same as Example 1
[0063]
[Evaluation]
Using the four buffer bodies as a set, a package was obtained in the same manner as in Evaluation 1 of Example 1. When the obtained package was transported by the same route as in Example 1, warping and deformation were often observed at the L-shaped end of the buffer. Further, the L-shape was opened by the fastening force of the fixture, and the five glass substrates were deviated from the substrate insertion groove by about 1 to 3 mm in the vicinity of the L-shape end portion. Could not be implemented.
[0064]
(Example 2)
A buffer was prepared in the same manner as in Example 1 except that a resin having the following physical properties was used.
[0065]
[Resin physical properties]
Material: Ethylene / propylene random copolymer resin
Foaming ratio: 7cm^Three/ G
Average particle diameter: 2.9 mm
Fusion rate: 78%
Compression modulus: 2940 N / cm²
Compression elastic index: 420
Recovery rate: 78%
[0066]
As a result of forming and transporting the packaging body in the same manner as in Example 1 using the buffer body, both the packing workability and the transportation performance were good.
[0067]
(Comparative Example 2)
A buffer was prepared in the same manner as in Example 1 except that a resin having the following physical properties was used.
[0068]
[Resin physical properties]
Material: Ethylene / propylene random copolymer resin
Foaming ratio: 30cm^Three/ G
Average particle diameter: 4.8 mm
Fusion rate: 98%
Compression modulus: 98 N / cm²
Compression elastic index: 3.3
Recovery rate: 92%
[0069]
As a result of forming and transporting the package in the same manner as in Example 1 using the buffer, the buffer is compressed and deformed by the fastening force of the fixture, and the glass substrate is bent and a normal package is obtained. could not.
[0070]
【The invention's effect】
As described above, in the present invention, by providing a wide side wall in the shock absorber, the rigidity is improved and the L-shaped restraining force of the main body is high. Therefore, in the package body in which the glass substrate is packed using the buffer body, the deformation of the buffer body is prevented, the groove of the glass substrate at the L-shaped end portion is not displaced, and the glass substrate is securely fixed and protected at the same time. The generation of dust and the damage of the glass substrate due to the friction between the glass substrate and the buffer are prevented. In addition, since the outermost glass substrate surface is widely covered with side walls to prevent dust adhesion and damage, a dummy substrate becomes unnecessary. Therefore, according to the present invention, there is provided a buffer body that has a high protective effect on the glass substrate, has good packing and removal workability, is adaptable to automation of the work, can be reused, and does not require a dummy substrate. Economic efficiency in packaging, storage and transportation of glass substrates can be greatly improved.
[Brief description of the drawings]
FIG. 1 is a perspective view of an embodiment of a shock absorber according to the present invention.
FIG. 2 is a perspective view of an embodiment of the packaging body of the present invention using the buffer body of FIG.
FIG. 3 is a partial cross-sectional schematic diagram showing an example of the shape of a substrate insertion groove of the buffer according to the present invention.
FIG. 4 is an explanatory diagram of the external dimensions of the buffer according to the present invention.
[Explanation of symbols]
1 buffer
2 body
3 Substrate insertion groove
4 Side walls
5 Fixture guide groove
6 Notches
11 Glass substrate
12 Fixture
13 ridges
21a, 21b Buffer plate
22, 22a, 22b Bottom of substrate insertion groove
23, 23a, 23b Top of ridge

Claims (3)

A buffer for glass substrate comprising an in-mold molded product of polyolefin resin expanded particles,
A main body provided with a plurality of substrate insertion grooves for fixing two side ends forming a corner of the glass substrate on the inner side along the L shape, the cross section having an L shape according to the shape of the corner of the glass substrate, A side wall extending in parallel with the substrate insertion groove and extending over the entire length of the L-shape, which is attached to both ends of the L-shape of the main body,
In the shape where the side wall is provided with an arc-shaped notch that is linear or outwardly convex at a corner opposite to the L-shaped corner of the rectangle having two side edges that contact the main body as a constituent side, The area exceeds 80% of the rectangular area and is 99% or less,
The average particle diameter of the expanded particles of the molded product is 1.5 to 5.0 mm, the fusion rate is 70% or more, the compression elastic index is 3.9 to 490, and the recovery rate is 60% or more. Buffer for glass substrate. In the above buffer, the maximum thickness of the main body is 10 to 100 mm, the ratio of the two L-shaped sides of the main body is 1.0 to 3.5 on the basis of the short side, the thickness of the side wall is 10 to 100 mm, The buffer for glass substrates according to claim 1, wherein the groove width is 1.0 to 4.0 times the thickness of the glass substrate, the groove depth is 3 to 15 mm, and the groove pitch is 6 to 100 mm. A plurality of glass substrates are arranged in parallel at predetermined intervals to form a rectangular parallelepiped, and corners of each substrate are inserted into the substrate insertion grooves of the glass substrate buffer according to claim 1 or 2, respectively, on the substrate surface. A packaging body, wherein four sides of the rectangular parallelepiped perpendicular to each other are fitted by the buffer body, and a long fixing tool is wound and fastened to the outside of the buffer body to be fixed.

Images