Glass plate laminate and glass plate packing body

Abstract

To provide a glass plate laminate capable of suppressing particles on the surface of a glass plate, and a glass plate package having the glass plate laminate.SOLUTION: A glass plate laminate 10 according to the present invention is stored in a storage container and has a structure in which a plurality of glass plates 2 and a plurality of glass plate interleaving papers 1 are alternately stacked. Of the stacking directions of the glass plate laminate 10, the direction away from the storage container is defined as a first direction D1, and the opposite direction is defined as a second direction D2. The main surface of the glass plate interleaving paper 1 on the first direction side is defined as a first main surface, and a region of the first main surface of the glass plate interleaving paper that is in contact with or corresponds to a main surface of an adjacent glass plate is defined as an in-plane region. In the glass plate laminate 10, when the color value of the in-plane region of the glass plate interleaving paper 1a located closest to the first direction side is defined as a first in-plane color and the color value of the in-plane region of the glass plate interleaving paper 1N located closest to a second direction side is defined as a second in-plane color, the color difference between the first in-plane color and the second in-plane color is a predetermined value or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a glass sheet laminate and a glass sheet package. [Background technology]

[0002] Glass plates incorporating electric circuits and the like on their surfaces, such as alkali-free glass plates used in liquid crystal displays, can suffer from disconnections and patterning defects even if they have slight scratches or contamination on their surfaces. Therefore, such glass plates are required to have extremely high surface properties. In order to prevent scratches and contamination on glass plates during storage and transportation, a method has been conventionally adopted in which glass plate interleaving paper (hereinafter also simply referred to as "interleaving paper") is sandwiched between the laminated glass plates to separate the surfaces of adjacent glass plates.

[0003] The form in which interleaving paper is interposed between glass plates is called a glass plate laminate. The glass plate laminate is stored in a storage container such as a pallet equipped with interleaving paper pressing members (lateral pressing members) that press interleaving paper protruding from the sides of the glass plate laminate from the sides. The form in which the glass plate laminate is stored in the storage container is called a glass plate package.

[0004] In the method of placing interleaving paper between glass plates, the interleaving paper and the surface of the glass plate come into direct contact. Therefore, various foreign matter such as paper powder generated from the interleaving paper, resin and adhesive components contained in the interleaving paper raw materials, fillers added during the papermaking process, additives such as pH adjusters, and material fragments mixed in during the process are present on the surface of the interleaving paper, and may be transferred to the surface of the glass plate with which it comes into contact and detected as particles. If there are a lot of particles on the glass plate, it can cause defects such as breakage of the fine wiring formed on the surface of the glass plate.

[0005] For example, Patent Document 1 describes that in a glass plate package in which a glass plate laminate in which multiple glass plates are laminated with interleaving paper interposed therebetween is packaged, when the content of higher saturated fatty acids in the interleaving paper relative to the mass of the interleaving paper is 0.08 mass% or less, transfer of stains from the interleaving paper to the glass plates can be suppressed. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2011 / 118502 Summary of the Invention [Problem to be solved by the invention]

[0007] However, even when the interleaf paper as described in Patent Document 1 is used, particles may still be detected on the surface of the glass plate, and there are cases where the use of the interleaf paper is insufficient in terms of particle suppression.

[0008] In view of the above, an object of the present invention is to provide a glass sheet laminate capable of suppressing particles on the surfaces of glass sheets, and a glass sheet package having the glass sheet laminate. [Means for solving the problem]

[0009] The present inventors have found that when a glass plate interleaf paper that has been discolored by light is used, particles are likely to be generated on the surface of the glass plate, and have completed the present invention.

[0010] That is, the present invention provides the following glass sheet laminate and glass sheet package. <1> A glass sheet laminate to be stored in a storage container, The glass plate laminate has a structure in which a plurality of glass plates and a plurality of glass plate interleaving papers are alternately laminated, The glass plate interleaf paper is an interleaf paper made of virgin pulp, Among the lamination directions of the glass sheet laminate, a direction away from the storage container is defined as a first direction, and a direction opposite to the first direction is defined as a second direction; a main surface of the glass plate interleaving paper on the first direction side is defined as a first main surface; An area of ​​the first main surface of the glass plate interleaving paper that is in contact with or corresponds to a main surface of an adjacent glass plate is defined as an in-plane area, In the glass plate laminate, the L of the in-plane region of the glass plate interleaving paper located closest to the first direction side * a * b * The color value in the color system is the first in-plane color, and the L * a * b * When the color value in the color system is the second in-plane color, A color difference ΔE between the first in-plane color and the second in-plane color * ab A glass sheet laminate, wherein the thickness is 0.58 or less. <2> A glass sheet laminate to be stored in a storage container, The glass plate laminate has a structure in which a plurality of glass plates and a plurality of glass plate interleaving papers are alternately laminated, The glass plate interleaf paper is an interleaf paper made of recycled paper pulp, Among the lamination directions of the glass sheet laminate, a direction away from the storage container is defined as a first direction, and a direction opposite to the first direction is defined as a second direction; a main surface of the glass plate interleaving paper on the first direction side is defined as a first main surface; An area of ​​the first main surface of the glass plate interleaving paper that is in contact with or corresponds to a main surface of an adjacent glass plate is defined as an in-plane area, In the glass plate laminate, the L of the in-plane region of the glass plate interleaving paper located closest to the first direction side * a * b * The color value in the color system is the first in-plane color, and the L * a * b * When the color value in the color system is the second in-plane color, A color difference ΔE between the first in-plane color and the second in-plane color * ab A glass sheet laminate, wherein the refractive index is 5.0 or less. <3> the above <1> or <2> and a storage container for storing the glass sheet laminate, A glass plate package in which the surface of the glass plate laminate on the second direction side is placed facing the storage container. Effect of the Invention

[0011] According to the present invention, it is possible to provide a glass plate laminate capable of suppressing particles on the surfaces of the glass plates by suppressing paper tanning of the glass plate interleaf paper, and a glass plate package having the glass plate laminate. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a side view showing one embodiment of a glass sheet laminate according to the present embodiment. [Diagram 2] FIG. 2 is an exploded perspective view showing a laminated state between a glass plate interleaving paper constituting a part of the glass plate laminate shown in FIG. 1 and an adjacent glass plate. [Diagram 3] FIG. 3 is an exploded perspective view showing a laminated state between a glass plate interleaving paper constituting a part of the glass plate laminate shown in FIG. 1 and an adjacent glass plate. [Figure 4] FIG. 4 is a side view showing another aspect of the glass sheet laminate according to the present embodiment. [Diagram 5] FIG. 5 is an exploded perspective view showing a laminated state between a glass plate interleaving paper constituting a part of the glass plate laminate shown in FIG. 2 and an adjacent glass plate. [Figure 6] FIG. 6 is a side view showing a schematic configuration of one example of a glass plate package. [Figure 7] FIG. 7 is a side view showing a schematic configuration of another example of a glass plate package. [Figure 8] FIG. 8 is a diagram showing the measurement results of the number of particles after a loading test using the glass-plate interleaf paper A. [Figure 9] FIG. 9 is a diagram showing the measurement results of the number of particles after a loading test using the glass-plate interleaf paper B. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described in detail below, but the present invention is not limited to the following embodiments and can be modified as desired without departing from the gist of the present invention. In addition, the symbol "to" indicating a numerical range is used to mean that the numerical values ​​before and after the symbol are included as the lower and upper limits. In the following drawings, the same reference numerals may be used to denote components or parts having the same function, and duplicated descriptions may be omitted or simplified. The embodiments shown in the drawings are schematic in order to clearly explain the present invention, and do not necessarily accurately represent the actual size or scale.

[0014] (Glass plate laminate) A glass plate laminate according to the present embodiment is a glass plate laminate to be stored in a storage container, the glass plate laminate having a structure in which a plurality of glass plates and a plurality of glass plate interleaving papers are alternately stacked, a lamination direction of the glass plate laminate is a first direction, a direction opposite to the first direction is a second direction, a main surface of the glass plate interleaving paper on the first direction side is a first main surface, a region of the first main surface of the glass plate interleaving paper that is in contact with or corresponds to a main surface of an adjacent glass plate is an in-plane region, and L of the in-plane region of the glass plate interleaving paper located closest to the first direction side in the glass plate laminate is a width of the glass plate laminate. * a * b * The color value in the color system is the first in-plane color, and the L * a * b * When the color value in the color system is the second in-plane color, the color difference ΔE between the first in-plane color and the second in-plane color * ab is less than or equal to a predetermined value.

[0015] First, a glass sheet laminate according to one aspect (aspect 1) of the present embodiment will be described with reference to Figs. 1 to 3. Fig. 1 is a side view showing a glass plate laminate according to embodiment 1. As shown in Fig. 1, a glass plate laminate 10 in this embodiment is placed on the surface (placement surface) of a back plate 22 of a storage container and stored in the storage container. The glass plate laminate 10 in this embodiment has a structure in which N glass plates 2 and N glass plate interleaving papers 1 are alternately laminated, where N is an integer of 2 or more.

[0016] In addition, when the direction perpendicular to the surface (placement surface) of the back plate 22 of the storage container is defined as the stacking direction of the glass plate laminate 10, the direction away from the storage container is defined as the first direction D1, and the direction opposite to the first direction D1 is defined as the second direction D2, the glass plate interleaving paper 1 closest to the first direction D1 is defined as the glass plate interleaving paper 1a, the second glass plate interleaving paper counting from the first direction D1 is defined as the glass plate interleaving paper 1b, and the glass plate interleaving paper 1 closest to the second direction D2 is defined as the glass plate interleaving paper 1N. The glass plate interleaving paper 1N is the Nth glass plate interleaving paper 1 counting from the glass plate interleaving paper 1a, and a total of N glass plate interleaving papers 1 are included in the glass plate laminate 10. When N is 2, the glass plate interleaving paper 1b corresponds to the glass plate interleaving paper 1N. Moreover, the glass plate 2 closest to the first direction D1 is referred to as glass plate 2a, the second glass plate counting from the first direction D1 is referred to as glass plate 2b, and the glass plate 2 closest to the second direction D2 is referred to as glass plate 2N. Note that glass plate 2N is the Nth glass plate 2 counting from glass plate 2a, and a total of N glass plates 2 are included in the glass plate laminate 10. When N is 2, glass plate 2b corresponds to glass plate 2N. In this embodiment, a glass plate 2a is laminated on the outermost surface of the glass plate laminate 10 on the first direction D1 side, and a glass plate interleaving paper 1N is laminated on the outermost surface of the glass plate laminate 10 on the second direction D2 side, and the glass plate interleaving paper 1N is placed on the mounting surface of the back plate 22 of the storage container.

[0017] For each glass plate interleaving paper 1, the main surface on the first direction side D1 is the first main surface, and the main surface on the second direction D2 side, i.e., the main surface opposite to the first main surface, is the second main surface. The glass plate interleaving paper 1a located closest to the first direction D1 has a first main surface 1a1 on the first direction D1 side and a second main surface 1a2 on the second direction D2 side. Similarly, the glass plate interleaving paper 1N located closest to the second direction D2 side has a first main surface 1N1 on the first direction D1 side and a second main surface 1N2 on the second direction D2 side.

[0018] Next, the in-plane region and the margin region on the first main surface of the glass plate interleaf in the glass plate laminate of this embodiment (embodiment 1) will be described. In this embodiment, the region of the first main surface of the glass plate interleaf 1 that contacts the main surface of the adjacent glass plate 2 is defined as the in-plane region. FIG. 2 is an exploded perspective view showing a laminated state of the glass plate interleaf 1a located closest to the first direction D1 side and the glass plate 2a adjacent to the first main surface 1a1 side of the glass plate interleaf 1a in the glass plate laminate 10 according to embodiment 1. As shown in FIG. 2, the in-plane region 1a1A on the first main surface 1a1 of the glass plate interleaf 1a can be defined as a region of the first main surface 1a1 where the glass plate interleaf 1a and the adjacent glass plate 2a overlap (contact) with each other. In this embodiment, the region of the first main surface 1a1 of the glass plate interleaf 1a other than the in-plane region 1a1A is defined as the margin region 1a1B. In FIG. 2, the protruding margin region 1a1B can also be said to be a region on the first main surface 1a1 of the glass plate interleaving paper 1a where the glass plate 2a does not overlap (contact) with the glass plate interleaving paper 1a.

[0019] Similarly, the in-plane region 1N1A and the margin region 1N1B on the first main surface 1N1 of the glass plate interleaf 1N located closest to the second direction side will be described. FIG. 3 is an exploded perspective view showing a laminated state between the glass plate interleaf 1N located closest to the second direction D1 side and the glass plate 2N adjacent to the first main surface 1N1 side of the glass plate interleaf 1N in the glass plate laminate 10 according to the first embodiment. As shown in FIG. 3, the in-plane region 1N1A on the first main surface 1N1 of the glass plate interleaf 1N can be defined as a region of the first main surface 1N1 where the glass plate interleaf 1N and the adjacent glass plate 2N overlap (contact) with each other. In this embodiment, the region of the first main surface 1N1 of the glass plate interleaf 1N other than the in-plane region 1N1A is defined as the margin region 1N1B. In FIG. 3, the protruding margin region 1N1B can also be said to be a region on the first main surface 1N1 of the glass plate interleaving paper 1N where the glass plate 2N does not overlap (contact) with the glass plate interleaving paper 1N.

[0020] Moreover, a glass sheet laminate according to one aspect (aspect 2) of the present embodiment will be described with reference to Figs. Fig. 4 is a side view showing a glass plate laminate according to embodiment 2. As shown in Fig. 4, the glass plate laminate 10 in this embodiment is placed on a back plate 22 of a storage container and stored in the storage container. The glass plate laminate 10 in this embodiment has a structure in which N glass plates 2 and N+1 glass plate interleaving papers 1 are alternately laminated, where N is an integer of 2 or more. In addition, when the direction perpendicular to the surface (mounting surface) of the back plate 22 of the storage container is the stacking direction, the direction away from the storage container is the first direction D1, and the direction opposite to the first direction D1 is the second direction D2, the glass plate interleaf paper 1 closest to the first direction D1 is the glass plate interleaf paper 1aa. The second glass plate interleaf paper closest to the first direction D1 is the glass plate interleaf paper 1a, the third glass plate interleaf paper closest to the first direction D1 is the glass plate interleaf paper 1b, and the glass plate interleaf paper 1 closest to the second direction D2 is the glass plate interleaf paper 1N. The glass plate interleaf paper 1N is the Nth glass plate interleaf paper counting from the glass plate interleaf paper 1a, and a total of N+1 glass plate interleaf papers 1 including the glass plate interleaf paper 1aa are included in the glass plate laminate 10. When N is 2, the glass plate interleaf paper 1b corresponds to the glass plate interleaf paper 1N. Moreover, the glass plate 2 closest to the first direction D1 is referred to as glass plate 2a, the second glass plate counting from the first direction D1 is referred to as glass plate 2b, and the glass plate 2 closest to the second direction D2 is referred to as glass plate 2N. Note that glass plate 2N is the Nth glass plate 2 counting from glass plate 2a, and a total of N glass plates 2 are included in the glass plate laminate 10. When N is 2, glass plate 2b corresponds to glass plate 2N. In this embodiment, a glass plate interleaving paper 1aa is laminated on the outermost surface of the glass plate laminate 10 on the first direction D1 side, and a glass plate interleaving paper 1N is laminated on the outermost surface of the glass plate laminate 10 on the second direction D2 side, and the glass plate interleaving paper 1N is placed on the mounting surface of the back panel 22 of the storage container.

[0021] For each glass plate interleaving paper 1, the main surface on the first direction side D1 is the first main surface, and the main surface on the second direction side D2, i.e., the main surface opposite to the first main surface, is the second main surface. The glass plate interleaving paper 1aa located closest to the first direction D1 has a first main surface 1aa1 on the first direction D1 side and a second main surface 1aa2 on the second direction D2 side. Similarly, the glass plate interleaving paper 1N located closest to the second direction D2 side has a first main surface 1N1 on the first direction D1 side and a second main surface 1N2 on the second direction D2 side.

[0022] Next, the in-plane region and the protruding margin region on the first main surface of the glass plate interleaving paper in the glass plate laminate of this embodiment (embodiment 2) will be described. In this embodiment, for the glass plate interleaving paper 1aa located closest to the first direction D1 side, the region of the first main surface that corresponds to the main surface of the adjacent glass plate 2a is defined as the in-plane region. This will be described in detail with reference to FIG.

[0023] FIG. 5 is an exploded perspective view illustrating a laminated state of a glass plate interleaving paper 1aa located closest to the first direction D1 side and a glass plate 2a adjacent to the glass plate interleaving paper 1aa in the glass plate laminate 10 of this embodiment. The glass plate interleaving paper 1aa and the glass plate 2a are laminated so that the second main surface 1aa2 of the glass plate interleaving paper 1aa is in contact with the glass plate 2a. Here, the region of the second main surface 1aa2 of the glass plate interleaving paper 1aa that is in contact with the main surface of the glass plate 2a is defined as a contact region 1aa2A, and the region that is not in contact with the main surface of the glass plate 2a is defined as a non-contact region 1aa2B. When the glass plate interleaving paper 1aa is viewed in plan from the lamination direction, the region of the first main surface 1aa1 that overlaps with the contact region 1aa2A of the opposing second main surface 1aa2 is defined as an in-plane region 1aa1A that corresponds to the main surface of the glass plate 2a. The region of the first main surface 1aa1 other than the in-plane region 1aa1A is defined as an out-of-plane region 1aa1B. The protruding margin region 1aa1B can also be said to be a region overlapping with the non-contact region 1aa2B on the second main surface 1aa2 when the glass plate interleaving paper 1aa is viewed in a plan view from the stacking direction.

[0024] In this embodiment, for the glass plate interleaving paper 1N located closest to the second direction side, the region of the first main surface 1N1 of the glass plate interleaving paper 1N that contacts the main surface of the adjacent glass plate 2N is defined as the in-plane region, as in the above-described embodiment 1. In addition, the region of the first main surface 1N1 of the glass plate interleaving paper 1N other than the in-plane region 1N1A is defined as the margin region 1N1B.

[0025] In the above-mentioned aspects 1 and 2, the glass plate laminate is stored on the surface (loading surface) of the back plate of the storage container so that the glass plate interleaf paper is placed on it, but this embodiment is not limited to this, and the glass plate laminate may be stored on the surface (loading surface) of the back plate of the storage container so that the glass plate is placed on it.

[0026] The present inventors found that particles are likely to be generated on the surface of the glass plate when a glass plate interleaf paper that has been discolored by light is used, and have completed the present invention. The reason for this is believed to be that when the glass plate interleaf paper is discolored by light, the amount of paper dust generated from the interleaf paper increases, and the amount of foreign matter that falls off increases. In this specification, particles refer to convex adhesions, and are detected by measurement using a foreign matter inspection device when paper dust or foreign matter is present on the surface of the glass plate. Particles are generated, for example, when paper dust or foreign matter generated from the glass plate interleaf paper is transferred to the glass plate.

[0027] "Paper discoloration" refers to deterioration of paper due to light, typically accompanied by discoloration of the paper. Specifically, it is known that the resin components (mainly lignin) contained in the paper undergo chemical changes due to sunlight (ultraviolet rays) and turn yellow to brown. In this specification, the degree of paper discoloration is evaluated by the color value of the glass plate interleaf paper. Generally, paper is often evaluated by ISO whiteness, which indicates whiteness, but in the case of paper discoloration, yellowing occurs, so evaluation by color value is considered to be more appropriate for accurately expressing the degree of change. Incidentally, the expression "paper discoloration" is sometimes used to refer to discoloration of glass caused by glass plate interleaf paper (the adhesion of foreign matter from the paper, or the reaction of components and moisture on the paper surface with components in the glass, resulting in cloudiness due to products, etc.), but here paper discoloration refers to the deterioration of the paper itself.

[0028] The in-plane region of the glass plate interleaf located at the most second direction side (for convenience, also referred to as the "lowest part") of the glass plate laminate is not exposed to normal light, and is therefore considered to be maintained in an undiscolored state. Specifically, the inventors have confirmed that when light of 10,000 Lux, which is greater than that received near indoor window glass, is irradiated onto a glass plate laminate including 100 glass plates, the illuminance near the lowest glass plate interleaf is about 0.01 to 0.05%, and most of the light is blocked. This can be said to be the same in the vicinity of the center of the in-plane region at the lowest part (back side) when the glass plate laminate is loaded on a so-called vertically stacked pallet, which is one form of storage container. Incidentally, the protruding margin region of the glass plate interleaf paper located at the furthest second direction side (lowest portion) of the glass plate laminate may be exposed to light and may cause paper discoloration.

[0029] In contrast, the glass plate interleaf located closest to the first direction side (for convenience, also referred to as the "top") of the glass plate laminate is easily exposed to light and is prone to paper fading. Therefore, when the color difference between the interleaf sheets at the top and bottom ends of the glass plate laminate (the interleaf sheet closest to the first direction side and the interleaf sheet closest to the second direction side) is large, it can be said that the degree of paper fading of the interleaf sheet on the top side (closest to the first direction side) is large. In contrast, the color difference ΔE between the above-mentioned first in-plane color and second in-plane color * ab If is equal to or less than a predetermined value, paper tanning of the interleaf paper on the uppermost side (closest to the first direction) is suppressed, and therefore particles on the surfaces of the glass plates of the entire glass plate laminate are suppressed.

[0030] In this specification, the color difference of the interleaf at the top and bottom ends of the glass plate laminate is calculated from the color difference between the first in-plane color and the second in-plane color. In other words, when the direction away from the container in the lamination direction of the glass plate laminate is defined as the first direction and the opposite direction to the first direction is defined as the second direction, the L of the in-plane area of ​​the glass plate interleaf located closest to the first direction in the glass plate laminate is calculated. * a * b * The color value in the color system is the first in-plane color. Also, the L * a * b* The color value in the color system is the second in-plane color. The color value of the glass plate interleaf paper can be measured by the method described in the Examples below, and the color value of the in-plane region is measured in a region that is 20% or more inward from the short sides of each side of the outline of the in-plane region.

[0031] Here, when the ash content of the glass plate interleaf paper is 0.001% to 0.5%, the color difference ΔE between the first in-plane color and the second in-plane color * ab is equal to or less than 0.58, preferably equal to or less than 0.57, and more preferably equal to or less than 0.56. In addition, when the ash content of the glass plate interleaf paper is more than 0.5% and less than 10%, the color difference ΔE between the first surface color and the second surface color * ab is 5.0 or less, preferably 4.5 or less, and more preferably 4.0 or less.

[0032] Waste paper pulp tends to have a higher ash content than virgin paper because hard foreign matter such as sand or metal is mixed in during waste paper collection, and more fillers, additives, detergents, etc. are used to increase cleanliness and whiteness. Glass plate interleaf paper with an ash content of 0.001% or more and 0.5% or less corresponds to interleaf paper made of virgin pulp, and glass plate interleaf paper with an ash content of more than 0.5 and 10% or less corresponds to interleaf paper made of waste paper pulp. In order to make the ash content less than 0.001%, excessive pulp must be refined, which significantly reduces productivity. In addition, when the ash content exceeds 10%, the amount of impurities is large, which makes the glass plate prone to scratches and particles, making it unsuitable as glass plate interleaf paper. Interleaf paper made of virgin pulp is often cleaner and is preferable from the viewpoint of reducing particles on the surface of the glass plate. On the other hand, in terms of productivity and required quality, interleaf paper made of waste paper pulp is sometimes preferably used. In this embodiment, the color difference ΔE * ab By setting the value below the above value, adhesion of particles resulting from paper tanning can be relatively suppressed in either case.

[0033] The inventors have found that paper fading causes an increase in particles, but also found that when the degree of paper fading is relatively mild, particles can be suppressed. * ab Although it may be 0, particles may be suppressed more when it is larger than 0. The reason for this is considered to be that the glass plate interleaf receives light moderately, which reduces the shedding property of paper powder and foreign matter. The inventors' study revealed that when the glass plate interleaf retains water to the extent that condensation occurs, the particles become very large, while when the moisture retention is moderately high, such as about 8% to 12%, the particles are reduced. When the moisture retention is excessive, moisture penetrates between the bonds between fibers or between foreign matter and fibers, and is liberated into water, or the resin component having a hydrophilic group dissolves in water, resulting in an increase in particles. In general, the moisture retention of paper is affected by additives in the paper and the humidity of the environment, but in the case of interleaf that does not contain additives that increase water retention, the moisture retention is about 5% to 7% at 25°C and 50 RH%. When the moisture retention is moderately high, a small amount of water molecules enter between the cellulose that constitutes the fibers or between the cellulose and foreign matter, forming stronger hydrogen bonds, which is considered to reduce the shedding property of paper powder and foreign matter. When the glass plate interleaf paper is exposed to an appropriate amount of light that does not cause damage, and the glass plate interleaf paper is heated and humidified, moisture retention in the paper is promoted, and once the bonds between the fibers or between the fibers and foreign matter have become strong, the bonds do not come apart within a certain range, even though the paper undergoes daily moisture absorption and release cycles, and it is therefore believed that the falling off of paper powder and foreign matter is reduced. As the light irradiation progresses further, it is believed that the fibers are damaged, the bonds between the fibers are broken, and falling off becomes predominant. When the ash content of the glass plate interleaf paper is 0.001% to 0.5%, the color difference ΔE between the first in-plane color and the second in-plane color is * ab is 0 or more, preferably 0.2 or more, and more preferably 0.3 or more. In addition, when the ash content of the glass plate interleaf paper is more than 0.5% to 10%, the color difference ΔE * ab is 0 or more, preferably 0.5 or more, and more preferably 1.0 or more.

[0034] When the paper is discolored, the color value of the interleaf paper is L * Therefore, when comparing the first in-plane color with the second in-plane color, the L value of the first in-plane color generally tends to be smaller. * The value is the L of the second surface color. * becomes smaller than the value. In this case, the L of the protruding area of ​​the glass plate interleaf located closest to the first direction side * a * b * The color value in the color space is the first output color, and the color difference ΔE between the first output color and the second in-plane color is * ab is preferably equal to or less than a predetermined value.

[0035] The projection area of ​​the glass plate interleaf is also the part where the glass plate interleaf is exposed in the glass plate laminate, and is the part where paper discoloration is more likely to occur. Although the projection area is not in direct contact with the main surface of the glass plate, if paper discoloration occurs in the projection area, particles may adhere to the edge surface of the glass plate, which may result in a deterioration in the quality of the glass plate. In response to this, the color difference ΔE between the first projection color and the second in-plane color * ab By keeping the color of the glass plate interleaf paper at or below a specified value, it can be said that the paper discoloration in the protruding area is suppressed, and the adhesion of particles to the edge of the glass plate can also be suppressed. Note that the protruding color of the glass plate interleaf paper is measured at least 10% inside the edge of the protruding area that comes into contact with the glass plate and at the cut edge of the interleaf paper.

[0036] When the ash content of the glass plate interleaf paper is 0.001% to 0.5%, the color difference ΔE between the first appearance color and the second in-plane color * ab is preferably 0.58 or less, more preferably 0.57 or less, and even more preferably 0.56 or less. In addition, when the ash content of the glass plate interleaf paper is more than 0.5% and less than 10%, the color difference ΔE between the first appearance color and the second in-plane color * ab is preferably 5.0 or less, more preferably 4.5 or less, and even more preferably 4.0 or less.

[0037] From the same viewpoint as the lower limit of the color difference between the first in-plane color and the second in-plane color, when the ash content of the glass plate interleaf paper is 0.001% to 0.5%, the color difference ΔE between the first out-of-plane color and the second in-plane color is * ab is 0 or more, preferably 0.2 or more, and more preferably 0.3 or more. In addition, when the ash content of the glass plate interleaf paper is more than 0.5% and 10% or less, the color difference ΔE * ab is 0 or more, preferably 0.5 or more, and more preferably 1.0 or more.

[0038] The absolute color value of the glass plate interleaf paper is not particularly limited because it depends on the type of glass plate interleaf paper used. For example, in the case of a glass plate interleaf paper made of virgin pulp and not intentionally colored, L * a * b * The color value in the color system is L * :90 or more, a * :-0.4 or more, b * : 6.0 or less is preferable, L * :95 or more and 99.5 or less, a * : more than -1.0 and less than -0.4, b * : 1.0 or more and less than 6.0 is more preferable. In addition, in the case of glass interleaf paper made of recycled pulp and not intentionally colored, * a * b * The color value in the color system is L * : 70 or more and less than 90, a * :-0.3 or more and 1.0 or less, b * : 9.0 or less is preferable, L * :75 or more and 85 or less, a * :-0.3 or more and 0.5 or less, b * : 2.0 or more and 9.0 or less is more preferable. In addition, "not intentionally colored" means, for example, that the glass plate interleaf paper does not contain any colorants such as paints, pigments, dyes, etc., or that even if they are contained as contaminants, the amount is 0.5 mass% or less.

[0039] The glass plate laminate 10 shown in FIG. 1 has a structure in which N sheets (N is an integer of 2 or more) of glass plate interleaving papers 1 and glass plates 2 are alternately laminated. The number of laminated glass plate interleaving papers 1 and glass plates 2 is not limited to this, and may be appropriately changed depending on various conditions such as the strength and size of the glass plates 2 and the size of the packaging container. The number of laminated glass plates (N) may be 2 or more, and the upper limit is, for example, 800 or less. The number of laminated glass plates is more preferably 150 to 600. Usually, the glass plate laminate 10 is laminated so that the total mass is 2000 kg or less.

[0040] The number of glass plates 2 and glass plate interleaving papers 1 laminated is usually either the same as the number of glass plates 2 and glass plate interleaving papers 1, or the number of glass plate interleaving papers 1 is one more than the number of glass plates 2.

[0041] (Method of manufacturing glass sheet laminate) The glass plate laminate according to the present embodiment can be manufactured by laminating glass plates and glass plate interleaving paper by a known method. In this case, for example, by covering the stack with a material having low light transmittance or a thick film or sheet immediately after the stack is formed, or by adding a light-absorbing material to the glass plate interleaving paper, the paper tarnish on the upper surface side of the glass plate laminate can be suppressed, and the glass plate laminate according to the present embodiment can be obtained.

[0042] (Glass plate) The type of glass plate constituting the glass plate laminate is not particularly limited, and known glass plates are used.For example, the glass plate is preferably a glass plate that is required to have a highly clean surface, such as a glass plate used in connection with the manufacture of liquid crystal products or semiconductor products, for example, a glass plate used for flat panel displays such as a glass substrate for liquid crystal displays and a glass substrate for organic EL displays, a glass plate used for cover glass, a glass plate used for semiconductor packages, and a glass plate used for electronic devices such as solar cells.

[0043] The material of the glass plate is not particularly limited and may be appropriately selected depending on the application, and examples thereof include soda-lime glass, aluminosilicate glass, borosilicate glass, alkali-free aluminosilicate glass, quartz glass, etc. In addition, it is also possible to use a glass plate made of glass that absorbs ultraviolet and infrared rays or tempered glass.

[0044] The shape, size, thickness, etc. of the glass plate are not particularly limited as long as the shape, size, thickness, etc. allow for storage and transportation of two or more sheets stacked together. The shape of the glass plate may be, for example, flat like the glass plate shown in FIG. 1, or may be curved, entirely or partially. The thickness of the glass plate may be appropriately adjusted depending on the application, and is, for example, 0.01 to 10 mm. The size of the glass plate may be, for example, about the size of the recently developed 8th generation glass (2200 mm × 2500 mm). In this case, the thickness of the glass plate is preferably 0.2 to 0.8 mm in terms of ensuring strength, and more preferably about 0.3 to 0.7 mm. The glass plate may be a laminated glass in which a plurality of glass plates are bonded together with an interlayer film sandwiched therebetween.

[0045] The method for producing the glass plate is not particularly limited. For example, the glass plate may be formed into a predetermined plate thickness by a pressing method, a down-draw method, a float method or the like, slowly cooled, and then processed by grinding, polishing or the like to produce a glass plate of a predetermined size and shape.

[0046] The glass plate may have a functional thin film on the surface. Specifically, the functional thin film is a conductive film (e.g., tin-doped indium oxide (ITO), zinc oxide (ZnO), tin oxide (SnO 2), Ag, a film having a Cr / Cu / Cr structure, and a heat ray shielding film (a layer having a structure of oxide (e.g., zinc oxide, titanium oxide, ITO, etc.) / Ag / oxide, etc.). Here, zinc oxide may be doped with Al, Ga, hydrogen, etc. Furthermore, tin oxide may be doped with F or Sb. Furthermore, Ag may be doped with Pd or Au.

[0047] (Glass plate interleaving paper) The type of glass plate interleaf paper constituting the glass plate laminate is not particularly limited, and known ones are used. For example, as described above, glass plate interleaf paper made of virgin pulp, glass plate interleaf paper made of recycled paper pulp, glass plate interleaf paper made of a mixed pulp of virgin pulp and recycled paper pulp, etc. can be appropriately selected according to the desired characteristics, etc. Note that the glass plate interleaf paper made of a specific pulp means that the ratio of the specific pulp to the pulp used as the raw material of the glass plate interleaf paper is substantially 100% by mass, and other types of pulp are not intentionally mixed in.

[0048] In this specification, virgin pulp does not refer to pulp made from paper produced or waste paper, but refers to pulp produced from wood or the like. The specific type of pulp in the virgin pulp is not particularly limited, and can be appropriately selected according to the properties required for the glass plate interleaf paper. As the virgin pulp, one type of pulp may be used alone, or multiple types of pulp may be used in combination. Examples of the types of pulp include chemical pulp such as kraft pulp (KP), sulfite pulp (SP), soda pulp (AP), mechanical pulp such as groundwood pulp (GP), thermomechanical pulp (TMP), chemi-thermomechanical pulp (CTMP), and semi-chemical pulp such as chemi-ground pulp (CGP) and semi-chemical pulp (SCP) as mechanical-chemical pulp between them. The pulp may be bleached or unbleached, and for example, among KP, bleached hardwood kraft pulp (LBKP), bleached softwood kraft pulp (NBKP), unbleached hardwood kraft pulp (LUKP), and unbleached softwood kraft pulp (NUKP) can be used.

[0049] Since glass sheet interleaving paper requires high cleanliness, the raw pulp is particularly preferably bleached kraft pulp (LBKP and NBKP), which has been bleached to remove resinous components derived from lignin and the like and has its amount reduced by washing.

[0050] (Recycled paper pulp) In this specification, waste paper pulp refers to pulp recovered from waste paper. Waste paper pulp is pulp derived from waste paper such as newspapers, magazines, and flyers, and is sometimes called deinked pulp (DIP). Deinked pulp refers to pulp that is made from waste paper and has been subjected to dust removal and deinking treatment to separate the ink. Waste paper pulp may be pulp derived from waste paper used as interleaving paper for glass plates.

[0051] The basis weight of glass plate interleaf paper is 30-100g / m 2 If the basis weight of the glass plate interleaving paper of this embodiment is small, the strength may decrease and the paper may be easily broken. Therefore, the basis weight of the glass plate interleaving paper of this embodiment is set to 30 g / m 2 More than 35 g / m is preferable. 2 More preferably, 40 g / m 2 More preferably, 45 g / m 2 The above is particularly preferred. On the other hand, if the basis weight is large, the weight increases, and the stack height increases when the glass plate interleaving paper and the glass plates are laminated to form a laminate, so that the number of sheets that can be stored in a container of a given height decreases. Therefore, the basis weight of the glass plate interleaving paper of this embodiment is set to 100 g / m 2 Less than 90 g / m is preferable. 2 Less than 80 g / m is more preferable. 2 More preferably, 70 g / m 2 The following are particularly preferred: The basis weight can be measured in accordance with JIS P 8124:2011. From the same viewpoint as above, the thickness of the glass plate interleaf paper of this embodiment is preferably 30 to 150 μm.

[0052] Since the glass plates to be laminated together with the glass plate interleaf of this embodiment are usually rectangular, it is preferable that the glass plate interleaf of this embodiment is also rectangular. In addition, in order to be usable for laminating large glass plates, the glass plate interleaf of this embodiment is preferably rectangular with at least one side having a length of 500 mm or more, more preferably 1000 mm or more, even more preferably 1500 mm or more, and particularly preferably 2200 mm or more. The upper limit is not particularly limited, but is, for example, 4000 mm or less. For example, when the glass plate is rectangular and has a size of 2200 mm × 2500 mm, the glass plate interleaf paper is preferably rectangular with a size of about 2280 mm × 2580 mm. When the glass plate is rectangular, the length of each side of the glass plate interleaf paper is preferably about 1.02 to 1.05 times the length of the corresponding side of the glass plate.

[0053] The glass plate interleaving paper of this embodiment may have various chemicals added thereto (coated, impregnated, etc.) within the scope of the effects of the present invention. Examples of chemicals added thereto or externally include aluminum sulfate, antifoaming agents, fixing agents, paper strength agents, retention improvers, coagulants, surfactants, sizing agents, antistatic agents, slime control agents, dryer release agents, polyvinyl alcohol, polyacrylamide, starch, cellulose derivatives such as CMC, and fillers (talc, clay, titanium dioxide, calcium carbonate, etc.).

[0054] The glass plate interleaf paper of the present embodiment can be produced by a known method, for example, a method including a preparation step of preparing pulp as a raw material, a preparation step of producing a pulp slurry from the pulp, and a papermaking step of producing the glass plate interleaf paper from the pulp slurry.

[0055] (Glass plate packaging) The glass sheet package of the present embodiment includes the glass sheet laminate of the present embodiment and a storage container for storing the glass sheet laminate.

[0056] When transporting or storing glass plates, glass plates and interleaf paper for glass plates are alternately laminated to form a laminate, which is then housed in a storage container and packaged to form a package (glass plate package). Examples of the storage container include a storage box and a pallet. Examples of the storage box include a storage box consisting of a box body for housing the glass plate laminate and a lid. In addition, glass plate packages using pallets include a horizontal type in which glass plates are horizontally stacked, and a vertical stacking type in which glass plates are stacked in an upright state at an angle, and this embodiment can be applied to either type. FIG. 6 shows a schematic configuration of an example of a glass plate package using a vertical stacking type pallet. In addition, FIG. 7 shows a schematic configuration of an example of a glass plate package using a horizontal type pallet.

[0057] The glass plate package of the present embodiment is a glass plate laminate having a first inner surface color L * The value is the L of the second surface color. * value, and the surface of the glass plate laminate on the second direction side is placed facing the placement plate of the storage container. In the state of the glass plate package, the surface that faces the placement plate of the storage container when the glass plate laminate is stored in the storage container is usually the lower surface side of the glass plate laminate that is less likely to cause paper tarnish.

[0058] The glass plate package 30 shown in FIG. 6 is packaged by placing a glass plate laminate 10, which is formed by stacking a plurality of glass plates 2 with interleaving paper 1 for glass plates interposed therebetween, on a pallet 31. The glass plate interleaving paper 1 is preferably also disposed between the pallet 31 and the glass plates 2. The pallet 31 is a known vertical stacking type pallet for packaging glass plates, and has a base 33, a back plate 32 erected on the upper surface of the base 33, and a bottom plate 34 placed on the upper surface of the base 33. The back plate 32 may be referred to as an inclined base or a placement plate. The bottom plate 34 may be referred to as a placement plate. In this example, the stacking direction of the glass plate laminate is perpendicular to the placement surface of the back plate 32 of the pallet 31.

[0059] One vertical surface of the back plate 32 (the surface in contact with the glass plate laminate 10; hereinafter, also referred to as the "inclined surface") is inclined with respect to the vertical direction. The angle of this inclined surface (indicated by α in FIG. 3) may be any angle that allows the laminated glass plate laminate 10 to be stably loaded, stored, and transported, and is usually 85° or less with respect to the horizontal direction, for example, 85° to 70°.

[0060] Moreover, the upper surface of the bottom plate 34 is inclined downward from the horizontal direction toward the back plate 32. In the illustrated example, as an example, the upper surface of the bottom plate 34 is configured to be at an angle of 90° with respect to the inclined surface of the back plate 32.

[0061] In the pallet 31, the glass plates 2 are placed on the upper surface of the bottom plate 34 and are stacked in a state of leaning against the inclined surface of the back plate 32. In addition, glass plate interleaving paper 1 is interposed between each glass plate. The surface of the frontmost glass plate may be covered with glass plate interleaving paper. When a vertically stacked pallet for packaging glass plates is used, the surface of the glass plate laminate on the second direction side is arranged to face the inclined surface of the back plate 32 of the pallet.

[0062] The glass plate package 50 shown in FIG. 7 is packaged by placing a glass plate laminate 10 on a pallet 51, the glass plates 2 being laminated with interleaving paper 1 for glass plates therebetween. The glass plate interleaving paper 1 is preferably also placed between the pallet 51 and the glass plates 2. The pallet 51 is a known pallet for horizontal glass plate packaging, and has a base 53 and a back plate 52 placed on the upper surface of the base 53. The base 53 also has supports 54 for stacking the pallet 51 at the corners of the upper surface (for example, at least four corners if the upper surface of the base 53 is rectangular). When a pallet for horizontal glass plate packaging is used, the surface of the glass plate laminate on the second direction side is disposed facing the back plate 52 of the pallet. The back plate 52 may be referred to as a placement plate. In this example, the stacking direction of the glass plate laminate is perpendicular to the placement surface of the back plate 52 of the pallet 51.

[0063] As described above, the present specification discloses the following: (1) A glass sheet laminate to be stored in a storage container, The glass plate laminate has a structure in which a plurality of glass plates and a plurality of glass plate interleaving papers are alternately laminated, The glass plate interleaf paper is an interleaf paper made of virgin pulp, Among the lamination directions of the glass sheet laminate, a direction away from the storage container is defined as a first direction, and a direction opposite to the first direction is defined as a second direction; a main surface of the glass plate interleaving paper on the first direction side is defined as a first main surface; An area of ​​the first main surface of the glass plate interleaving paper that is in contact with or corresponds to a main surface of an adjacent glass plate is defined as an in-plane area, In the glass plate laminate, the L of the in-plane region of the glass plate interleaving paper located closest to the first direction side * a * b * The color value in the color system is the first in-plane color, and the L * a * b * When the color value in the color system is the second in-plane color, A color difference ΔE between the first in-plane color and the second in-plane color * ab A glass sheet laminate, wherein the thickness is 0.58 or less. (2) a region other than the in-plane region of the first main surface of the glass plate interleaving paper is defined as an exposure margin region; The L of the protruding margin area of ​​the glass plate interleaving paper located closest to the first direction side * a * b * When the color value in the color system is the first representative color, The color difference ΔE between the first appearance color and the second in-plane color * ab The glass sheet laminate according to (1), wherein the thickness is 0.58 or less. (3) The glass plate interleaving paper is L * 90% or more, and an ash content is 0.001% or more and 0.5% or less. (4) The glass plate interleaving paper is L *90% or more, and an ash content is 0.001% or more and 0.5% or less. (5) A glass sheet laminate to be stored in a storage container, The glass plate laminate has a structure in which a plurality of glass plates and a plurality of glass plate interleaving papers are alternately laminated, The glass plate interleaf paper is an interleaf paper made of recycled paper pulp, Among the lamination directions of the glass sheet laminate, a direction away from the storage container is defined as a first direction, and a direction opposite to the first direction is defined as a second direction; a main surface of the glass plate interleaving paper on the first direction side is defined as a first main surface; An area of ​​the first main surface of the glass plate interleaving paper that is in contact with or corresponds to a main surface of an adjacent glass plate is defined as an in-plane area, In the glass plate laminate, the L of the in-plane region of the glass plate interleaving paper located closest to the first direction side * a * b * The color value in the color system is the first in-plane color, and the L * a * b * When the color value in the color system is the second in-plane color, A color difference ΔE between the first in-plane color and the second in-plane color * ab A glass sheet laminate, wherein the refractive index is 5.0 or less. (6) A region other than the in-plane region of the first main surface of the glass plate interleaving paper is defined as an exposure region, The L of the protruding margin area of ​​the glass plate interleaving paper located closest to the first direction side * a * b * When the color value in the color system is the first representative color, The color difference ΔE between the first appearance color and the second in-plane color * ab The glass sheet laminate according to (4), wherein the refractive index is 5.0 or less. (7) The glass plate interleaving paper is L * The glass sheet laminate according to (5), wherein the content of the ash is more than 0.5% and less than 90%, and the ash content is more than 10%. (8) The glass plate interleaving paper is L * The glass sheet laminate according to (6), wherein the content of the ash is more than 0.5% and less than 90%, and the ash content is more than 10%. (9) The glass sheet laminate according to any one of (1) to (8), wherein a glass sheet interleaving paper is laminated on each of the outermost surface on the first direction side and the outermost surface on the second direction side of the glass sheet laminate. (10) The glass plate laminate according to any one of (1) to (8), wherein a glass plate is laminated on an outermost surface of the glass plate laminate on the first direction side, and a glass plate interleaving paper is laminated on an outermost surface of the glass plate laminate on the second direction side. (11) A glass sheet laminate according to any one of (1) to (10) above, and a storage container for storing the glass sheet laminate, A glass plate package in which the surface of the glass plate laminate on the second direction side is placed facing the storage container. EXAMPLES

[0064] The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

[0065] (Test Example 1: Sunlight exposure test of glass plate interleaving paper) As a glass plate interleaf paper, glass plate interleaf paper A (L) made of virgin pulp (softwood bleached kraft pulp) * = 97.5, a * =-0.6, b * = 5.1, ash content 0.20%) and glass plate interleaf paper B (L * =83.1, a * =0.5, b * = 5.7, ash content 3.5%) was prepared. A single sheet of glass plate interleaf paper was placed, without rubbing, into a transparent polyethylene bag that had been treated with an ionizer (static electricity eliminator) to serve as a sample for the sunlight exposure test. Multiple pieces of glass plate interleaf paper A and B were prepared. The prepared samples were attached to a south-facing window surface from the indoor side where sunlight enters in a test room and stored for a specified period of time to conduct a sunlight exposure test. Some samples were not exposed to sunlight and were stored in a black box in the dark.

[0066] (Measurement of color value) Sample 1 was stored in the dark for 2 months, and samples 2 to 4 were stored for 0.5, 1, and 2 months and exposed to sunlight, respectively. The L * a * b * The color values ​​in the color system were measured. In addition, when measuring the color, 30 or more sheets of glass plate interleaf paper processed under the same conditions were stacked to a size of 50 mm x 50 mm or more, and the measurement was performed 5 or more times for each condition while changing the top glass plate interleaf paper each time, and the average value was taken as the color measurement result. If the number of layers of glass plate interleaf paper is small, the light of the colorimeter is easily transmitted through the glass plate interleaf paper, so that the light incident on the light receiving part of the colorimeter is more affected by the object behind the glass plate interleaf paper, and there is a possibility that the color measurement cannot be performed correctly. The more the number of glass plate interleaf paper sheets is, the closer the value becomes to a constant value, and when 30 or more sheets are stacked, the color measurement result becomes approximately constant regardless of the number of sheets, so a more accurate color measurement result can be obtained. The color difference results obtained from the measurement of the color value are shown in Table 1. In addition, the color difference values ​​of samples 2 to 4 are values ​​based on the color value of sample 1 (stored in a dark place for 2 months).

[0067] (Color measurement conditions) Equipment: Konica Minolta spectrophotometer CM-700d Illumination and receiving optical system: SCI method (including specular reflection) Measurement diameter: SAV (diameter 6 mm) Observation light source: D65 light source Observation conditions: 10° field of view Color system: L * a * b * Color system

[0068] [Table 1]

[0069] (Test example 2: Loading test) Glass plate laminates 1 to 4 were produced using samples produced under the same conditions as the glass plate interleaving papers of Samples 1 to 4 in Test Example 1, and the number of particles on the surfaces of the glass plates after storage under specified conditions was measured. Each sample of glass plate interleaf paper (520 mm long x 420 mm wide) and glass plates (470 mm long x 370 mm wide x 0.5 mm thick, non-alkali glass substrate: AN100 manufactured by AGC Inc.) were alternately laminated to obtain a glass plate laminate containing 30 or more glass plates. A load equivalent to 2 kPa was applied to the obtained glass plate laminate, and the laminate was stored for 16 hours under conditions of a temperature of 80°C and a relative humidity of 40%. The temperature was raised from room temperature to 80°C and lowered from 80°C to room temperature over 4 hours each.

[0070] <Measurement of the number of particles on the surface of a glass plate> The glass plate taken out of the glass plate laminates 1 to 4 after the loading test was passed through a cleaning machine with the wiring surface facing upward. The cleaning machine is composed of two rows of shower pipes, one above the other, through which pure water (ion-exchanged water) flows at a piping pressure of 1 MPa and a flow rate of 20 L / min, and the nozzles are uniformly fan-shaped, and each pipe has five nozzles for spraying water. The glass plate passed through the cleaning machine at a speed of 3 m / min, and was dried with an air knife that sprays clean dry air, to obtain a cleaned substrate. The cleaned substrate was measured in Normal (1.0 μm) mode using a foreign matter inspection machine for FPD (HS-830e, manufactured by Toray Engineering Co., Ltd.) to obtain the number of particles. Note that the particles in the foreign matter inspection machine generally include not only convex deposits but also concave scratches, but in this specification, convex deposits are referred to as particles and concave defects are referred to as scratches. The sizes of the particles found were classified and evaluated as follows. The results are shown in Figures 8 and 9. Note that the bar graphs in Figures 8 and 9 are based on the average values ​​obtained by measuring samples under the same conditions three or more times, and the maximum and minimum values ​​are also shown. L (Large): The diameter of the standard particle is 5 μm or more. M (Medium): The diameter of the standard particle is 3 μm or more and less than 5 μm. S (Small): The diameter of the standard particle is 1 μm or more and less than 3 μm.

[0071] From the results in Table 1, the longer the glass plate interleaf paper is exposed to light, the more the color value changes, and the color difference ΔE * ab It can be seen that the greater the degree of paper discoloration, that is, the greater the degree of paper discoloration. Moreover, from the results of Figs. 8 and 9, it can be seen that the greater the degree of paper discoloration of the glass plate interleaf paper, the greater the number of particles detected. From this, it can be seen that when glass plates and glass plate interleaf papers are alternately laminated to form a glass plate laminate, the color difference ΔE between the first in-plane color and the second in-plane color * ab It can be seen that if is equal to or less than a predetermined value, particles on the glass plate surface can be suppressed. [Explanation of symbols]

[0072] 1, 1aa, 1a, 1b, 1N Glass plate interleaving paper 1aa1, 1a1, 1N1 First main surface 1aa2, 1a2, 1N2 2nd principal surface 1aa1A, 1a1A, 1N1A in-plane area 1aa1B, 1a1B, 1N1B starting area 2, 2a, 2b, 2N Glass plates 1aa2A contact area 1aa2B non-contact area 10 Glass plate laminate 22 Back plate 30 Glass plate packaging 31 Palette 32 Back plate 33 Foundation 34 Bottom plate 50 Glass plate packaging 51 Palettes 52 Back plate 53 Foundation 54 Post D1 1st direction D2 2nd direction

Claims

1. A glass sheet laminate to be stored in a storage container, The glass plate laminate has a structure in which a plurality of glass plates and a plurality of glass plate interleaving papers are alternately laminated, The glass plate interleaf paper is an interleaf paper made of virgin pulp, A direction away from the container in a stacking direction of the glass sheet stack is defined as a first direction, and a direction opposite to the first direction is defined as a second direction; a main surface of the glass plate interleaving paper on the first direction side is defined as a first main surface; An area of ​​the first main surface of the glass plate interleaving paper that is in contact with or corresponds to a main surface of an adjacent glass plate is defined as an in-plane area, In the glass plate laminate, the L of the in-plane region of the glass plate interleaving paper located closest to the first direction side ＊ a ＊ b ＊ The color value in the color system is a first in-plane color, and the L ＊ a ＊ b ＊ When the color value in the color system is the second in-plane color, A color difference ΔE between the first in-plane color and the second in-plane color ＊ ａｂ The glass sheet laminate,

2. A region other than the in-plane region of the first main surface of the glass plate interleaving paper is defined as an exposure region, The L of the projection area of ​​the glass plate interleaving paper located closest to the first direction side ＊ a ＊ b ＊ When the color value in the color system is the first representative color, A color difference ΔE between the first appearance color and the second in-plane color ＊ ａｂ The glass sheet laminate according to claim 1 , wherein the thickness of the glass sheet is 0.58 or less.

3. The glass plate interleaving paper is L ＊2. The glass sheet laminate according to claim 1, wherein the content of the ash is 0.001% or more and 0.5% or less.

4. The glass plate interleaving paper is L ＊ The glass sheet laminate according to claim 2, wherein the content of the ash is 0.001% or more and 0.5% or less.

5. A glass sheet laminate to be stored in a storage container, The glass plate laminate has a structure in which a plurality of glass plates and a plurality of glass plate interleaving papers are alternately laminated, The glass plate interleaf paper is an interleaf paper made of recycled paper pulp, A direction away from the container in a stacking direction of the glass sheet stack is defined as a first direction, and a direction opposite to the first direction is defined as a second direction; a main surface of the glass plate interleaving paper on the first direction side is defined as a first main surface; An area of ​​the first main surface of the glass plate interleaving paper that is in contact with or corresponds to a main surface of an adjacent glass plate is defined as an in-plane area, In the glass plate laminate, the L of the in-plane region of the glass plate interleaving paper located closest to the first direction side ＊ a ＊ b ＊ The color value in the color system is a first in-plane color, and the L ＊ a ＊ b ＊ When the color value in the color system is the second in-plane color, A color difference ΔE between the first in-plane color and the second in-plane color ＊ ａｂ The glass sheet laminate,

6. A region other than the in-plane region of the first main surface of the glass plate interleaving paper is defined as an exposure region, The L of the projection area of ​​the glass plate interleaving paper located closest to the first direction side ＊ a ＊ b ＊ When the color value in the color system is the first representative color, A color difference ΔE between the first appearance color and the second in-plane color ＊ ａｂ The glass sheet laminate according to claim 4, wherein the glass sheet laminate has a thickness of 5.0 or less.

7. The glass plate interleaving paper is L ＊ The glass sheet laminate according to claim 5, wherein the glass sheet laminate has a viscosity of 70% or more and less than 90% and an ash content of more than 0.5% and less than 10%.

8. The glass plate interleaving paper is L ＊ The glass sheet laminate according to claim 6, wherein the glass sheet laminate has a viscosity of 1000 saturation temperature of 100° C. or more and a viscosity of 1 ....

9. The glass plate laminate according to any one of claims 1 to 8, wherein a glass plate interleaving paper is laminated on each of the outermost surface on the first direction side and the outermost surface on the second direction side of the glass plate laminate.

10. The glass plate laminate according to any one of claims 1 to 8, wherein a glass plate is laminated on the outermost surface of the glass plate laminate on the first direction side, and a glass plate interleaving paper is laminated on the outermost surface of the glass plate laminate on the second direction side. The glass plate laminate according to any one of claims 1 to 8,

11. A glass sheet laminate according to any one of claims 1 to 8, and a storage container for storing the glass sheet laminate, A glass plate package in which the surface of the glass plate laminate on the second direction side is placed facing the storage container.

Images