KR20040012868A - Buffer for Glass Substrate - Google Patents

Abstract

The present invention provides at least one of an L-shaped cross-section of a main body 2 having an L-shaped cross section, using an in-mold molded article of polyolefin resin foam particles having specific physical properties as a buffer for integrally packaging a plurality of glass substrates formed by forming an electronic component or the like. A side wall 4 having a length of 30 to 100% is formed on the side from the apex of this L toward the end. This makes it suitable for packaging operations in clean rooms, especially for automation and reusable.

Description

Buffer for Glass Substrate

In recent years, the production of electronic and electrical related devices, especially liquid crystal displays, plasma displays, and portable terminals represented by mobile phones, which are one of peripheral devices of personal computers, has grown rapidly due to the development of the information technology industry represented by the Internet. There is a strong demand for developing a buffer-related technology for use in packaging, conveying, and the like. Especially, glass substrates, such as a color filter glass substrate, TFT glass substrate (the board | substrate with which the thin film transistor was assembled), and the liquid crystal panel substrate, such as a glass substrate which assembled electronic components, such as a semiconductor device, are thin in thickness. It is vulnerable to dropping shocks and vibrations that occur during transportation, and its configuration is very fine, which makes it difficult to handle from outside. In particular, when conveying a glass substrate before processing or a semi-finished product before it becomes a final product, the electronic component is treated in an exposed state, and thus, its function may be more severely affected by static electricity, contaminants and dust, thereby impairing its function. .

Therefore, many packaging techniques for conveying safely without damaging a glass substrate have been proposed.

As an example, the technique disclosed by Unexamined-Japanese-Patent No. 5-319456 is mentioned. The technical point is a buffer including a polyolefin bead foam having a specific characteristic, the cross section of which has an L-shape, and a plurality of substrate insertion openings are provided inside the L-shape. In packaging a glass substrate, a plurality of glass substrates are arranged in parallel at predetermined intervals to form a rectangular parallelepiped, and corner portions of each of the substrates are respectively inserted into the substrate insertion openings of the buffer body, and the rectangular parallelepiped of the rectangular parallelepiped with respect to the substrate surface is formed. The four sides are fitted with the above-mentioned buffer and fixed with a fixture such as rubber or tape as necessary.

However, when the fasteners such as rubber or tape are fixed to the outside of the shock absorber, the fastening force is concentrated on the corners of the shock absorber, and thus the L-shape is opened. There was no case.

In addition, the L-shaped buffer body is formed with a groove width of the substrate insertion hole is equal to or slightly narrower than the thickness of the glass substrate, thereby fixing the glass substrate using the advantage of elastic recovery upon compression, which is characteristic of the polyolefin bead foam. It is. Therefore, although it is effective for the oscillation resistance by vibrating friction with the glass substrate during conveyance, in the packaging of the original glass substrate, the frictional resistance with the glass substrate becomes adverse effect, and if the glass substrate is forcibly inserted into the substrate insertion opening, There is a problem that a very thin glass substrate, such as 0.6 to 0.8 mm, is easily bent and broken, and takes a long time if the work is carefully performed to avoid breakage. This also applies to taking out a glass substrate. In particular, in recent years, in view of saving labor, introduction of automatic storage devices and take-out devices for glass substrates has been in progress, but trouble has been generated from the above problems, and it is pointed out that the shock absorber is not suitable for automation.

Moreover, when inserting a glass substrate into a board | substrate insertion opening, there also exists the problem that a minute frictional wound generate | occur | produces on the glass substrate surface from frictional resistance.

Such automation suitability is a practical characteristic that is becoming more and more important with the recent increase in the size of glass substrates, but the buffers have also been enlarged, causing problems of warpage and deformation as conventional buffers.

The present invention provides a buffer for transport that protects a glass substrate formed by forming an electronic component such as a semiconductor device on a glass substrate from damage caused by vibration during transportation, and a plurality of glass substrates simultaneously packed using the buffer. It is about a package.

1 is a perspective view of one embodiment of a buffer of the present invention.

2 is a perspective view of another embodiment of the buffer of the present invention.

3 is a perspective view of another embodiment of the buffer of the present invention.

4 is a perspective view of another embodiment of the buffer of the present invention.

5 is a perspective view of another embodiment of the buffer of the present invention.

Fig. 6 is a perspective view of one embodiment of the package of the present invention using the buffer of Fig. 1.

Fig. 7 is a perspective view of one embodiment of the package of the present invention using the buffer of Fig. 4.

8A, 8B and 8C are partial cross-sectional schematic diagrams showing examples of shapes of substrate insertion holes of the buffer of the present invention.

9 is an explanatory view of the external dimensions of the buffer of the present invention.

In the drawings, reference numeral 1 denotes a buffer body, 2 a main body, 3 a substrate insertion hole, 4 a side wall, 5 a fixture guide, 6 apex, 11 a glass substrate, 12 a fixture, 13 a convex, 21a and 21b The buffer plates, 22, 22a and 22b are the bottom of the substrate insert, and 23, 23a and 23b are the top of the convex.

<Best Mode for Carrying Out the Invention>

The shock absorber of the present invention is characterized in that a side wall is provided on a side surface of an L-shaped main body having a substrate insertion port that fixes two side ends forming a corner portion of a glass substrate. Accordingly, in the package using the shock absorber of the present invention, the L-shape of the main body is fixed by the side wall, and the L-shaped extension is prevented.

EMBODIMENT OF THE INVENTION Hereinafter, the buffer of this invention is given and described embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view of a preferred embodiment of the buffer of the present invention, in which 1 is a buffer of this embodiment, 2 is a body, 3 is a substrate insert, 4 is a side wall, and 5 is a fixture guide.

The basic configuration of the buffer of the present invention includes a main body 2 having a cross-section having an L shape according to the shape of a corner portion of the glass substrate, and side walls 4 provided on at least one side of both sides forming the L shape of the main body 2. Is done. 1 shows an example in which the side wall 4 is provided on both sides of the main body. The main body 2 is provided with a plurality of substrate insertion holes 3 for fixing two side ends forming the corner portions of the glass substrate inside the L-shape, and the side wall 4 is formed parallel to the substrate insertion hole 3. .

The side wall 4 which concerns on this invention is formed over 30-100% of length from the L-shaped vertex 6 of the main body 2 toward the edge part, The shape of this side wall 4 and the main body 2 In the rectangle which has the two short sides which contact | connect a constituent side, it is a shape which provided the cutting | disconnection area | region in the rectangular corner part corresponding to the L-shaped vertex 6 of the main body 2. As shown in FIG. The shape of the cutting zone is not particularly limited, and in addition to the triangle shown in FIG. 1, it can be cut into an outwardly convex arc shape as shown in FIG. 2 or a rectangle as shown in FIG. 3, and the area of the side wall 4 is equal to this. The size is adjusted to be 30 to 80% of the area of the rectangle.

In FIG. 4, the example which attached the side wall 4 only to one side surface of the main body 2 is shown. In addition, the side wall 4 is shown in FIG. 5 in the both sides of the main body 2, The example which made this side wall 4 to the way from the L-shaped vertex 6 to the edge part is shown.

6, the perspective view of the package which packaged the glass substrate using the buffer of FIG. 1 is shown.

In the figure, 11 is a glass substrate, 12 is a fixture. As shown in Fig. 6, the buffer bodies 1 of the present invention basically use four as one set, and a plurality of glass substrates 11 are arranged in parallel at predetermined intervals to form a rectangular parallelepiped, and The corner part is inserted into the board | substrate insertion opening of the buffer body 1, and the four sides of this rectangular parallelepiped are fitted into this buffer body 1. After that, the long fixture 12 is wound, fastened and fixed to the fixture guide 5 formed on the outside of the shock absorber 1 as necessary. In the shock absorber of the present invention, the fixture guide 5 can be formed as necessary.

In the shock absorber 1 of this invention, as shown in FIG. 1, the L-shape of the main body 2 is fixed by the side wall 4, and is buffered by providing the side wall 4 in the side surface of the main body 2. As shown in FIG. Since the rigidity of the sieve itself is improved, even if the fastening force of the fastener 12 acts intensively on the L-shaped vertex 6 in the packaged body as shown in FIG. 6, the L-shape does not occur and the L-shape does not occur. Groove-out of the board | substrate at the edge part is prevented. Such L-shaped restraining force can form the side wall 4 on one side of the main body 2, and higher effects are obtained when the side walls 4 are placed on both sides of the main body 2 as shown in Figs. . In addition, as shown in FIG. 4, when the side wall 4 is attached only to one side of the main body 2, the L-shaped binding force is lower than that when the side wall 4 is attached to both sides, but a plurality of buffers can be stored and transported. have.

In addition, since the cutting section is formed in the diagonal portion corresponding to the L-shaped vertex 6 of the side wall 4, the bending is unlikely to occur in the side wall 4 at this diagonal portion, and the contact with the glass substrate 11 is suppressed. It is.

The buffer of the present invention is an in-mold molded article of polyolefin resin foam particles. The molded body is filled with polyolefin resin foamable particles in a mold, and then heated and foamed to expand the foamed particles to be molded into a desired shape. It is inexpensive to 1/10 or less, and since it can mass-produce a molded object of a complicated shape with good dimensional accuracy easily and efficiently, it is economical and is suitable for mass production.

In addition, in-mold molded articles of polyolefin-based resin foam particles have very little generation of minute dust even by agitation with the glass substrate, and the contamination of the glass substrate by the dust is very small. In addition, the molded body is hardly deformed even when subjected to an external force during handling or transportation, and even if deformed, it has excellent recoverability and high dimensional stability. In addition, such a buffer is washed with pure water every time before use in repeated use, but the molded article has a low water absorption and excellent dryness.

The polyolefin resin used in the buffer of the present invention may be either crosslinked or uncrosslinked. Specific examples of the resin material include low, medium and high density polyethylene, linear low density polyethylene, linear ultra low density polyethylene, and metallocene catalysts. Polyethylene-based resins and copolymerized components represented by polyethylene, ethylene-vinyl acetate copolymer resins, and the like, in which random and block copolymerized resins of ethylene, butene-1, 4-methylpentene-1 and the like and propylene or two or more kinds thereof are blended. Preferably selected from the composition.

Particularly suitable resin materials for the present invention include random copolymer resins of polyethylene and propylene having a resin density of 0.927 to 0.970 g / cm ³ . Polyethylenes having a resin density of not less than 0.39 g / cm ³ have a suitable compressive elasticity index of the buffer described later, and are difficult to deform when an external force is applied. In addition, it is not necessary to reduce the expansion ratio of the expanded particles in order to obtain a specific compressive elasticity index, which is preferable in terms of light weight and economical efficiency. In addition, polyethylene having a resin density of 0.97 g / cm ³ or less is preferable because of its sufficient flexibility and its oscillation resistance and recovery properties. In addition, the propylene random copolymer resin is most preferably used in the present invention because it has a high compressive elasticity index, and also has excellent recoverability and durability in repeated use.

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 compressive elasticity index is 3.9 to 490, and the recovery rate is 60% or more.

As described above, the average particle diameter of the foamed particles is 1.5 to 5.0 mm, preferably 2.0 to 4.5 mm. In the case where the average particle diameter of the expanded particles is 1.5 to 5.0 mm, the expanded particles can be filled to the minute portion of the substrate insertion hole during molding, and the mold shape and the reproducibility of the dimensions are good. In addition, sufficient foaming expandability is exhibited because the ratio of the surface area per one foamed particle (volume) is small and the gas pressure (air) monoacidity in the particles is small in the steam heating step during molding in the mold. As a result, a space | gap is hard to generate | occur | produce between the foamed particles which comprise an in-mold molded object, and since a contaminant or dust enters this space | gap, there is no possibility that the cleanness of a buffer cannot be maintained, and it is preferable.

In addition, the average particle diameter of the foamed particle which comprises the buffer of this invention is represented by three ball-point pens of 100 mm in length on the surface of an in-mold molded object, and measures the number of foamed particle which contact | connects on this straight line, The average particle diameter C [mm] is computed from (A). In addition, evaluation is made into the average value of the value calculated | required by three straight lines.

C = (1.626 × L) / N (A)

L: Centerline length [mm]

N: number of particles

The fusion rate of the molded article according to the present invention refers to the total length in the thickness direction at the fracture surface when a cutting medium having a depth of about 1 mm is inserted in the thickness direction of the buffer body, and the cutting medium is bent outward to break. It is the number which expressed the number of the foam particle which the particle | grain interface is broken (material destruction) with respect to the total number of foam particles of the area over 75 mm in length in percentage. In the buffer of the present invention, a sufficient mechanical strength can be obtained at a fusion rate of 70% or more, and when the fastener is fastened by the fastener, the fastener penetrates into the buffer and destroys the buffer, or the buffer is easily broken. Problem becomes difficult to occur. Moreover, the problem that micro voids generate | occur | produce between foamed particle | grains and the water absorptivity by a capillary phenomenon is expressed is also preferable because a fusion rate hardly arises at 70% or more.

In addition, when the compressive elasticity index of the molded body is 3.9 or more, even when subjected to an external force, the shock absorber is hardly deformed, so that the durability is good, and even if the size of the glass substrate exceeds a size of 600 mm × 700 mm, the permanentness due to the weight of the glass substrate Distortion hardly occurs, and fixing of a glass substrate is easy and preferable. In addition, when the compressive elasticity index is 490 or less, it is not particularly necessary to reduce the foaming ratio of the buffer, which is preferable in terms of light weight and economical efficiency. Moreover, in the range whose compressive elasticity index is 490 or less, since flexibility is favorable, it is excellent in oscillation resistance, and also excellent in cushioning performance, such as a drop impact, it is preferable.

The compressive elastic modulus according to the present invention is a value obtained by dividing the compressive elastic modulus [N / cm ² ] by the foaming magnification, and the compressive elastic modulus is a value obtained according to JIS K 7220 for the test piece which measured the following foaming magnification. mm / min. In the case where the test piece thickness is less than 20 mm, a plurality of sheets are measured so that the thickness is about 20 mm.

Measuring method of compression magnification: A flat specimen 50 mm wide, 50 mm long and 20 mm thick was extracted from the buffer, the weight [g] was measured to 10 mg, and then the vernier caliper was used to measure the width, length, By measuring the thickness, the volume [cm ³ ] is calculated to calculate the expansion ratio E [cm ³ / g] from the following equation (B).

E = volume / weight [cm ³ / g] ... (B)

Moreover, within the range whose compressive elasticity index is 3.9-490, since the recovery rate is 60% or more, the repeat durability which is a characteristic of the in-molded object of polyolefin resin foam particle is favorable, and even if a frequency of use becomes high, it is preferable, since deformation is small. In addition, a recovery rate is 50 mm in width, 50 mm in length, and 20 mm in thickness from the buffer, and 10 mm using a compression test apparatus "Autograph AG-5000D" manufactured by Shimazu Seisakusho. After compressing to 50% of the thickness of the test piece at a compression rate of / min, immediately remove until the load becomes zero at the same speed, and measure the thickness at the moment when the load becomes zero and recovers from the following formula (C) [%] Is calculated. In addition, when the thickness of a test piece is less than 20 mm, multiple sheets overlap measurement so that thickness may be about 20 mm.

R = (T ₁ / T ₀ ) × 100 [%] ... (C)

T ₀ : thickness of test piece before test [mm]

T ₁ : thickness of test piece after test (when load is zero) [mm]

Next, the external dimensions of the buffer of the present invention will be described in detail with reference to FIGS. 8 and 9. 8 is a partial cross-sectional view of a direction orthogonal to the L-shape of the main body in the embodiment of the shock absorber of the present invention, and FIG. 9 is a side view of the embodiment of FIG. 5. In Fig. 8, reference numeral 13 denotes a convex jaw sandwiched between adjacent substrate inserts 3, 22 a bottom of the substrate insert 3, 23 a top of the convex jaw 13, and Figs. (9a) and (21b) are the buffer plates which comprise the L-shape of a main body, and form the short side and the long side of L-shape, respectively. In addition, (22a) and (22b) are the bottom part of the board | substrate insertion opening formed in the buffer plates 21a and 21b, respectively, and correspond to FIG. 23a and 23b are the tops of the protrusions of the buffer plates 21a and 21b corresponding to FIG.

As shown in Fig. 9, the buffer of the present invention has approximately L characters in the main body, and the maximum thicknesses of the buffer plates 21a and 21b constituting the L characters (thickness in the convex 13 in Fig. 8). t1) and the thickness (not shown) of the side wall 4 depend on the size of the glass substrate to be targeted, but are preferably selected in the range of 10 to 100 mm, more preferably 15 to 50 mm. When this thickness is in the said preferable range, rigidity as a buffer body is enough, a curvature or deformation hardly generate | occur | produce, and sufficient L-shaped restraint force in the side wall 4 is obtained. In addition, within the above range, the productivity of the buffer is also good, and the volume of the buffer and the package is appropriate, so that the economic efficiency is good. Moreover, as thickness of the buffer plates 21a and 21b in the bottom part 22a, 22b of the board | substrate insertion opening 3, 5 mm or more is preferable in order to acquire the said effect.

In the buffer of the present invention, the ratio (tL / tS) based on the short sides of the L-shaped short sides (tS) and the long sides (tL) of the main body is preferably 1.0 to 3.5, and more preferably. 1.0 to 3.3. If this ratio is in the said range, the balance of a long side and a short side will be favorable, the fixation stability of a rectangular glass substrate will be favorable, and it will become difficult to produce the damage by the bending of a glass substrate.

Moreover, in this invention, it is preferable that each buffer fits 10% or more of the side ends of a glass substrate at the time of packaging within the range of the said short side and long side. If the length of the side end of the glass substrate to which the buffer fits is 10% or more, the supporting portion of the glass substrate becomes sufficient, and when the drop impact is received, the glass substrate is less likely to be damaged even if the impact load is concentrated on the portion, The stress regarding the buffer is also lowered, and oscillation in contact friction due to vibration during conveyance is reduced, which is preferable in view of cleanliness. Moreover, in each side end of a glass substrate, when the length supported by two buffer bodies is 92% or less of a side end, since the contact part of a glass substrate and a buffer body is not so big, there exists a problem in the oscillation property by the contact friction by the vibration during conveyance. It is also preferable from the viewpoint of cleanliness, and from the viewpoint that the buffer is not enlarged more than necessary, the economy is also good.

In addition, as the side wall 4 of the buffer of the present invention, a certain size is required in order to maintain the L-shape composed of the buffer plates 21a and 21b. In the present invention, the side wall 4 is the main body 2. The length of the edges ta and tb which are in contact with is required to be 30% to 100% by making the lengths tA and tB up to the L-shaped edges 100%. 1 to 4 are examples of ta = tA and tb = tB, and FIG. 5 is an example of ta <tA and tb <tB. In addition, ta / tA and tb / tB may be the same or different. As the area of the side wall 4, a wider one is preferable in maintaining the L-shape, and a cutting zone for preventing warpage at a diagonal portion corresponding to the L-shaped vertex 6 of the side wall 4 is preferable. In the present invention, the area of the side wall 4 (the area obtained by subtracting the area excluded from the cutting area from the rectangular area (ta × tb)) is 30 to 80% of the rectangular area.

As a specific external dimension, Preferably, the short side (tS) is 100-500 mm, and the long side (tL) is 100-1100 mm, The length of the direction orthogonal to an L-shape is 150-150 although it depends also on the number of sheets of a glass substrate 600 mm.

Next, the board insertion opening 3 is demonstrated using FIG. In the buffer of the present invention, the groove width t3 of the plurality of substrate insertion ports 3 provided in the main body 2 is preferably 1.0 to 4.0 times the thickness of the glass substrate to be packaged, more preferably 1.2 to 3.5 times. When the said numerical value is 1.0 times or more, workability | operativity at the time of the insertion and take-out of a glass substrate by manual is good, and even if automatic insertion is performed, the damage of a glass substrate is hard to produce. In addition, at 4.0 times or less, there is no problem even when automating the insertion and withdrawal of the glass substrate, and there is no rattling caused by the vibration impact during conveyance of the glass substrate, thereby preventing the glass substrate from being broken and generating less dust. Preferred at The actual size of the groove width is on the order of 0.5 to 3.0 mm.

In addition, the groove depth t2 of the substrate insertion port 3 is preferably in the range of 3 to 15 mm in consideration of the size, weight of the glass substrate, the compressive elasticity index of the molded body, and the like. If the groove depth is 3 mm or more, the glass substrate is preferable because it does not easily fall and be damaged even when subjected to vibration shock during transportation or drop impact during handling. In addition, in the vicinity of the side end of the glass substrate that is in contact with the buffer, minute frictional scratches are likely to occur due to the friction caused by the vibrational impact during conveyance. In the processing of the glass substrate, the region is cut and removed, but the depth of the substrate insertion port 3 is reduced. Is 15 mm or less, since the region to be cut and removed may be small. Moreover, since the oscillation by the friction of a glass substrate and a buffer body also becomes small, it is preferable also from a cleanliness viewpoint.

In addition, the groove pitch t4 of the substrate inserting hole 3 takes into account the type of glass substrate (for example, display component substrate such as mother glass and color filter glass substrate), its size, weight, compressive elasticity index of the molded body, groove width and the like. Preferably, it can select from the range of 6-100 mm. That is, when receiving the vibration shock during conveyance and the drop shock at the time of handling, it can set so that a glass substrate may not bend and a board may contact.

As a cross-sectional shape of the board insertion hole 3 provided in the buffer body of this invention, as shown in FIG. 8A, the cross section of the convex part 13 between the board | substrate insertion openings with which groove width t3 is the same in the bottom part and an opening, ie, adjacent, is shown. This rectangular shape may be formed, but in consideration of the insertion workability of the glass substrate, the groove width of the substrate insertion hole 3 is widened at the opening, that is, an arc shape in which the top cross section of the convex 13 is convex upward (FIG. 8B). In addition, the shape made into trapezoidal shape (FIG. 8C) is preferable.

As described above, the buffer of the present invention uses four in one set, and after packaging the glass substrate, long fasteners are wound, fastened and fixed around the glass substrate to obtain a package. As a fastener used here, a long thing, such as a string form and a tape form, can be long, For example, the tape made from polypropylene is used preferably. In general, the package is stored in a clean polyethylene bag or the like, sealed, and transported to prevent contamination or dust from invading the outside.

In addition, although the example which used four identical buffers in one set was shown in embodiment of FIG. 6, in this invention, it is not limited to this, In the case of the size, packaging, take-out workability, especially an automatic apparatus of a glass substrate In consideration of the extraction position, etc., two kinds of buffers of different sizes can be used. For example, a combination of a large buffer is used for the bottom part to which a load is applied, and a small buffer is used for the upper part. In addition, it is not necessary to correspond the short side of a buffer body to the short side of a glass substrate, and two buffer bodies can support one side of a glass substrate with one short side and the other long side.

As shown in Fig. 7, in the case of using a buffer in which the side wall illustrated in Fig. 4 is provided only on one side of the main body, the buffer member is combined so that the arrangement of the side walls alternately. It is preferable to use so that glass substrate fixing performance may not be biased.

Moreover, the buffer of this invention can be used also for storage other than the use as a conveyance of a glass substrate. Specifically, two buffers of the present invention are fixed to one set in an outer box such as plastic corrugated cardboard to insert a glass substrate. In this case, the buffer on the glass substrate may or may not be used. In addition, a cover is used as necessary to prevent ingress of dust and contaminants.

In view of the above problems, the problem of the present invention is that the glass substrate is not provided with the groove of the glass substrate at the L-shaped end portion of the buffer at the time of packaging the glass substrate, and even if an external force such as vibration or drop impact is applied during transportation or handling, It is providing the buffer for glass substrates which can protect the said metal safely.

Another object of the present invention is suitable for automating the packaging and extraction of the glass substrate, and does not generate dust easily even when the glass substrate is brought into contact with the glass substrate. It is to provide the buffer for.

Another object of the present invention is to provide a package packaged using this buffer.

The first aspect of the present invention consists of in-die molding of polyolefin resin foam particles,

The cross section shows an L shape according to the shape of the corner portion of the glass substrate, and the L-shaped inner surface of the L-shaped inner surface is provided with a plurality of substrate insertion holes for fixing two side ends forming the corner portion of the glass substrate along the L-shaped portion, and the L-shaped portion of the main body. A buffer for a glass substrate having a side wall parallel to the substrate insertion hole and attached to at least one side of the side and extending from the corner portion of this L to both ends, each having a length of 30 to 100%,

The side wall has a shape in which a cutting zone is provided at an edge portion corresponding to the L-shaped vertex of the corner portion of the rectangle having the two short sides that the side wall and the main body come into contact with, and the area of the side wall is 30 to 30 of the rectangle. 80%,

The said polyolefin resin foam particle relates to the buffer for glass substrates whose average particle diameter is 1.5-5.0 mm, fusion rate is 70% or more, compressive elasticity index is 3.9-490, and recovery rate is 60% or more.

In the above buffer, the maximum thickness of the main body is 10 to 100 mm, the ratio of the two sides of the L-shape of the main body is 1.0 to 3.5, the side wall is 10 to 100 mm, and the depth of the groove of the substrate insertion hole is 3 to 15. It is preferable that mm and a groove pitch are 6-100 mm, and it is preferable that the said side wall is attached to both L-shaped side surfaces of a main body, respectively.

In addition, a second aspect of the present invention, a plurality of glass substrates; A buffer for the glass substrate in which the plurality of glass substrates are arranged in parallel at a predetermined interval by inserting edge portions of each glass substrate into the substrate insertion openings; And it relates to a package comprising a fastener wound on the L-shaped outer surface of the buffer.

The said package body is obtained by inserting each edge part of several glass substrates into the board | substrate insertion opening of the above-mentioned buffer for glass substrates, and winding and fastening a fastener to the L-shaped outer surface of this buffer body and fixing it.

The buffer of the following specification was manufactured, the glass substrate was packaged, and evaluation was performed.

<Example 1>

[Glass substrate specifications]

Use: Mother glass for liquid crystal display

Dimensions: 850 mm × 1000 mm

Thickness: 0.7 mm

[Resin Properties]

Material: ethylene / propylene random copolymer resin

Foam magnification: 20 cm ³ / g

Average particle diameter: 3.6 mm

Fusion rate: 88%

Compression Modulus: 559 N / cm ²

Compressive elasticity index: 28.0

Recovery rate: 88%

[Dimensions]

Number of glass substrate storage: 12

main body

Short side: 350 mm

Long side: 460 mm

L-shaped orthogonal length: 415 mm

Thickness: 35 mm

Sidewall

Shape: Fig. 2 (arc cutting area, placed on both sides of the body)

L-shape length: 100% (short side) × 100% (long side)

Area: 70% of the rectangle

Thickness: 35 mm

Board Insert

Groove width: 1.5 mm

Groove depth: 9.5 mm

Groove pitch: 25 mm

Shape: Fig.3 (c), height 5.0mm of straight part, height 4.5mm of trapezoidal part

[Evaluation 1]

Twelve pieces of the glass substrates were packaged as one set of the four buffers, and a polypropylene tape was wound, fastened and fixed to two portions as a fastener to obtain a package. When the package was transported in a normal path, there was no warpage or deformation at the L-shaped end of the buffer body, the packaging workability of the glass substrate was good, and the L-shape was maintained to maintain the glass substrate in the package. Home without missing, was able to transport stably.

[Evaluation 2]

In addition, in order to evaluate the buffer performance of the buffer of the present Example, the package of Evaluation 1 was packaged in the cardboard box (CD-4 of JIS Z 1506 standard), and the free fall test was done on condition of the following.

ㆍ drop test conditions

Drop height: 30 cm

Package drop: only the floor of the package

Number of drops: 3 times

Under the above conditions, there was no dropout of the glass substrate even after three drops, the packaging state before the test was maintained, and no damage to the glass substrate was observed. In addition, when the surface of the glass substrate was visually observed and observed, adhesion of dust was not observed at all.

[Evaluation 3]

In addition, in order to evaluate the glass substrate fixing performance of the buffer of this invention, the vibration test was done about the package of Evaluation 1 on the following conditions. In addition, the vibration test was carried out by fixing this package to the excitation table of a vibration test apparatus, based on the test method of JISZ0232.

ㆍ vibration test condition

Vibration direction: up and down

Oscillation Waveform: Sine Wave

Sweep: algebraic (frequency: 5 to 100 Hz, sweep rate: 0.5 octaves / minute)

Vibration Acceleration: ± 0.75 G

Oscillation time: 30 minutes

After the vibration test was completed, the packaging fixing state of the glass substrate was visually observed, but there was a slight distortion on the glass substrate, but no glass substrate was dropped from the substrate insertion opening. Did.

Example 2

The buffer of the following specification was manufactured, the glass substrate was packaged, and evaluation was performed.

[Glass substrate specifications]

Same as Example 1

[Resin Properties]

Material: ethylene / propylene random copolymer resin

Foam magnification: 20 cm ³ / g

Average particle diameter: 3.6 mm

Fusion rate: 86%

Compression Modulus: 530 N / cm ²

Compressive elasticity index: 26.5

Recovery Rate: 89%

[Dimensions]

Number of glass substrate storage: 12

main body

Same as Example 1

Sidewall

Shape: Fig. 1 (triangular cutting area, placed on both sides of the body)

L-shape length: 100% (short side) × 100% (long side)

Area: 50% of the rectangle

Thickness: 35 mm

Board Insert

Same as Example 1

Using the above-mentioned buffer, the package was formed and transported in the same manner as in Example 1, and as a result, both packaging workability and transportability were good.

Example 3

The buffer of the following specification was produced, the glass substrate was packaged, and it evaluated.

[Glass substrate specifications]

Same as Example 1

[Resin Properties]

Material: ethylene / propylene random copolymer resin

Foam magnification: 20 cm ³ / g

Average particle diameter: 3.6 mm

Fusion rate: 83%

Compression Modulus: 510 N / cm ²

Compressive elasticity index: 25.5

Recovery rate: 88%

[Dimensions]

Number of glass substrate storage: 12

main body

Same as Example 1

Sidewall

Shape: Figure 3 (rectangular cutting zone, placed on both sides of the body)

L-shape length: 100% (short side) × 100% (long side)

Area: 60% of the rectangle

Thickness: 35 mm

Board Insert

Same as Example 1

Using the above buffer, a package was formed and transported in the same manner as in Example 1, and as a result, both packaging workability and transportability were good.

<Example 4>

The buffer of the following specification was manufactured, the glass substrate was packaged, and evaluation was performed.

[Glass substrate specifications]

Same as Example 1

[Resin Properties]

Material: ethylene / propylene random copolymer resin

Foam magnification: 20 cm ³ / g

Average particle diameter: 3.6 mm

Fusion rate: 87%

Compression Modulus: 539 N / cm ²

Compressive elasticity index: 27.0

Recovery Rate: 89%

[Dimensions]

Number of glass substrate storage: 12

main body

Same as Example 1

Sidewall

Shape: The side wall in which the arc-shaped cutting zone of FIG. 2 is installed is placed only on one side of the main body.

L-shape length: 100% (short side) × 100% (long side)

Area: 70% of the rectangle

Thickness: 35 mm

Board Insert

Same as Example 1

As the buffer was used, as shown in Fig. 7, the glass substrates were packaged with the side walls alternately arranged, and the package was formed and transported. As a result, both packaging workability and transportability were good. In addition, since the side walls are provided only on one side of the main body, space saving during storage is realized.

Example 5

A buffer was produced in the same manner as in Example 2 except that the following resin was used, and the glass substrates were packaged for evaluation.

[Resin Properties]

Material: Crosslinked Polyethylene Resin

Resin Density: O.93O g / cm ³

Foam magnification: 10 cm ³ / g

Average particle diameter: 2.8 mm

Fusion rate: 98%

Compression Modulus: 539 N / cm ²

Compressive elasticity index: 27.0

Recovery Rate: 93%

Packaging was formed and transported in the same manner as in Example 1 using the above buffer, and as a result, both packaging workability and transportability were good.

Comparative Example 1

The buffer only for the main body without the side wall of the following specification was manufactured, and the glass substrate was packaged and evaluated.

[Glass substrate specifications]

Same as Example 1

[Resin Properties]

Material: ethylene / propylene random copolymer resin

Foam magnification: 20 cm ³ / g

Average particle diameter: 3.6 mm

Fusion rate: 86%

Compression Modulus: 549 N / cm ²

Compressive elasticity index: 27.5

Recovery Rate: 87%

[Dimensions]

Number of glass substrate storage: 12

main body

Short side: 350 mm

Long side: 460 mm

L-shaped orthogonal length: 400 mm

Thickness: 35 mm

Board Insert

Same as Example 1

[evaluation]

Using 4 buffers as one set, it carried out similarly to the evaluation 1 of Example 1, and obtained the package. When the obtained package was transported in the same route as in Example 1, many warpages and deformations were observed at the L-shaped end of the buffer. In addition, the L-shape was opened by the fastening force of the fastener, and groove | channel missing was seen, and it was not able to carry out about evaluation 2 and evaluation 3 similar to Example 1. FIG.

Comparative Example 2

A buffer was prepared in the same manner as in Example 1 except that the following physical resin was used.

[Resin Properties]

Material: ethylene / propylene random copolymer resin

Foam magnification: 20 cm ³ / g

Average particle diameter: 3.6 mm

Fusion rate: 60%

Compression Modulus: 549 N / cm ²

Compressive elasticity index: 27.5

Recovery rate: 85%

Using the above-mentioned shock absorber, the package was formed and transported in the same manner as in Example 1, so that there was no bending or deformation of the L-shaped end portion, the workability at the time of packaging was good, and no groove was removed. However, after performing the same free fall test as in [Evaluation 2] of Example 1, there was no dropout of the glass substrate, but minute cracking occurred at the end portion of the glass substrate that was in contact with the substrate insertion hole in the long side direction of the buffer placed on the ground. It was. As a result of observing this buffer in detail to find out the cause of this crack, it is thought that the crack generate | occur | produced between foamed particle | grains, and the glass substrate penetrated the buffer by drop impact. In addition, a drop in which the expanded particles were dropped was also confirmed, and it was found that the durability to withstand repeated use is inferior to that of the buffer of Example 1. That is, since the fusion rate of the molded object which comprises a buffer body does not reach 70%, it is thought that excessive distortion generate | occur | produced when it fell to the mechanical strength which a buffer body originally had and received a drop impact.

Comparative Example 3

The buffer of the following specification was manufactured, the glass substrate was packaged, and evaluation was performed.

[Glass substrate specifications]

Same as Example 1

[Resin Properties]

Material: ethylene / propylene random copolymer resin

Foam magnification: 20 cm ³ / g

Average particle diameter: 3.6 mm

Fusion rate: 86%

Compression Modulus: 530 N / cm ²

Compressive elasticity index: 26.5

Recovery Rate: 89%

[Dimensions]

Number of glass substrate storage: 12

main body

Short side: 350 mm

Long side: 460 mm

L-shaped orthogonal length: 415 mm

Thickness: 35 mm

Sidewall

Shape: Figure 5 (triangular cutting zone, placed on both sides of the body)

L-shaped length: 25% (short side) × 25% (long side)

Area: 31% of the rectangle

Thickness: 35 mm

Board Insert

Same as Example 1

[evaluation]

Using 4 buffers as one set, it carried out similarly to the evaluation 1 of Example 1, and obtained the package. When the obtained package was transported in the same path as in Example 1, the L-shaped restraint force of the side wall was insufficient, resulting in warpage or deformation at the L-shaped end of the buffer.

<Example 6>

Except for changing the thickness of the side wall to 8 mm, the same buffer as in Example 1 was produced and evaluated. As the side wall was thin, a slight warpage or deformation was seen at the L-shaped end of the buffer.

Although this invention was detailed also demonstrated with reference to the specific embodiment, it is clear for those skilled in the art that various changes and correction can be added without deviating from the mind and range of this invention.

This application is based on the JP Patent application (patent application 2001-164291) of an application on May 31, 2001, The content is taken in here as a reference.

As described above, in the present invention, the rigidity is improved by providing sidewalls to the shock absorber, and the L-shaped restraint force of the main body is high. Therefore, in the package which packaged the glass substrate using this buffer body, deformation | transformation of a buffer body is prevented, the groove | channel of the glass substrate in a L-shaped edge part is avoided, and a glass substrate is firmly fixed and protected, and At the same time, generation of dust and damage to the glass substrate due to the friction between the glass substrate and the buffer body are prevented. Therefore, according to the present invention, the protective effect of the glass substrate is high, the packaging and removal workability is good, and it is suitable for the automation of this work, and can be reused, and the economic efficiency in the packaging, storage and transportation of the glass substrate can be improved. It can greatly improve.

Claims (4)

It consists of in-die molding of polyolefin resin foam particle, The L-shaped cross section shows an L-shape, the L-shaped inner surface of which is formed in parallel with the L-shaped side edges, and the L-shaped edge parallel to the substrate insertion hole provided on at least one side of the L-shaped side of the main body. Each side has a sidewall over the length of 30 to 10%, towards both ends, The side wall has a shape in which a cutting zone is provided at an edge portion of the rectangle having two short sides that the side wall is in contact with the main body as a constituent edge, corresponding to the L-vertex, and the area of the side wall is 30 To 80%, The said polyolefin resin foam particle is a buffer for glass substrates whose average particle diameter is 1.5-5.0 mm, fusion rate is 70% or more, compressive elasticity index is 3.9-490, and recovery rate is 60% or more. According to claim 1, wherein the maximum thickness of the main body of 10 to 100 mm, the ratio of the two sides of the L-shape of the main body 1.0 to 3.5, the side wall thickness of 10 to 100 mm, the groove depth of the substrate insertion hole 3 to 15 mm And a buffer for glass substrates having a groove pitch of 6 to 100 mm. The glass substrate buffer according to claim 1 or 2, wherein the sidewalls are respectively provided on both L-shaped sides of the main body. A plurality of glass substrates; The glass substrate buffer according to any one of claims 1 to 3, wherein the plurality of glass substrates are arranged in parallel at predetermined intervals by inserting edge portions of the glass substrates into the substrate insertion openings; And Fixture wound on L-shaped outer surface of this buffer Package consisting of.