JP2008163507A - Mat mount and mat board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mat mount having excellent suitability for curling and suitability for cutting, and to provide a mat board formed by using the mat mount. <P>SOLUTION: The mat mount used for the mat board for picture mounting, which has a front surface layer, a back surface layer, and an intermediate layer between the front surface layer and the back surface layer, and has a thickness of 700-1,200 μm, is regulated so that the freeness of the front surface layer may be ≥10 ml higher than that of the intermediate layer, at least one of the front surface of the front surface layer and the back surface of the back surface layer is coated or impregnated with a water-soluble polymer, and the water absorbing capacity of the surface of the front surface layer may be 10-60 g/m<SP>2</SP>based on JIS-P8140. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a mat mount and a mat board used for an indispensable amount for display and preservation of paintings, prints, photographs, posters, calligraphy and the like (hereinafter collectively referred to as “works”). More specifically, the present invention relates to a mat mount excellent in curling aptitude and cut aptitude and a mat board using the mat mount.

  As shown in FIG. 1, the frame 1 for storing works such as paintings and photographs includes a frame 2, a work 3, a glazing 4 made of glass or an acrylic resin plate on the surface for viewing the work 3, and a mat board 5. And the mount board 6 and the back board 7.

Here, the mat board 5 is
1. Space 8 is created so that work 3 and glazing 4 are not in close contact.
2. Trim with the margin of work 3 hidden, and frame it without cutting work 3.
3. Work 3 and image 2 will be harmonized and effective to enhance work 3's image.
4). The work 3 is protected from acidification of the work 3 itself, and the preservation of the work 3 is enhanced.
It plays a role such as.

  Such a mat board 5 is composed of a mat mount 9 and a surface material 10 bonded to the surface of the mat mount 9 as shown in a sectional view in FIG. As the surface material 10, high-grade watercolor paper, Japanese paper, colored paper, embossed paper, or the like is used. For this reason, the mat board 5 has different atmospheres depending on the surface material 10 to be used, and the expression of the work 3 stored in the forehead 1 can be changed by selecting the mat board 5.

  As shown in FIG. 2, the mat board 5 is formed by pasting a surface material 10 only on one side of a mat mount 9. Is generally used. For this reason, when the surface material 10 is bonded to the mat mount 9, there is a problem that the mat board 5 is curled by the moisture of the glue.

  If the mat board 5 is curled, not only will the commercial value of the mat board 5 be reduced, but also in terms of functionality, there will be a partial gap between the glazing 4 and the mat board 5, so There is a problem that the image of the work 3 is invited down rather than making the image up.

  Moreover, since a gap is partially generated between the mat board 5 and the work 3, there also arises a problem that the work 3 cannot be firmly fixed at a predetermined position.

  Further, as shown in FIG. 1, the mat board 5 is provided with a hollow window portion 11 in accordance with the size of the work. As a cutting method for providing the window portion 11, there is a method of inserting a blade perpendicular to the surface of the mat board 5. Recently, in order to further enhance the cosmetics of the forehead 1 using the mat board 5, The mainstream method is to use a special machine to cut the blade with an angle of about 45 degrees with respect to the surface of the mat board 5 (inclined cut), and also use the cut surface (cut surface) 12 of the window portion 11 of the mat board 5. It has become to.

  That is, when the window portion 11 is formed by performing an inclined cut on the mat board 5, the cut surface 12 appears greatly. That is, the surface material 10 using a mat mount, high-quality watercolor paper, Japanese paper, colored paper, or the like appears greatly. For this reason, if the cutting surface 12 of the mat board 5 is also used, the work 3 contained in the forehead 1 can be produced more effectively.

  However, as the method of performing an inclined cut on the mat board 5 becomes mainstream, the mat mount 9 is required to have a cutting ability in particular. In other words, it has been required that the cut surface of the mat mount 9 is free from cuts, cuts, burrs, burrs, whiskers, salmons, and the like (hereinafter collectively referred to as “blemish” in the present invention). . If such cuts are present on the cut surface of the mat mount 9, it will be obstructive and the cosmetics will be reduced, and instead of effectively producing the work 3, the value of the work will be lowered.

  However, there are few documents that have been specially studied with respect to the mat mount, and for example, the mat mount shown in Patent Document 1 has been proposed.

  The mat mount described in Patent Document 1 contains alkaline powder and pollutant gas adsorbing powder in papermaking fibers, and the cold water extraction pH value is in the range of 6.5 to 8.5 for a long time. Even if it is used in contact with the work, the work is not adversely affected, and the work itself is protected by removing pollutant gases from the air and the backboard plywood. The curl aptitude problem that the mat board curls and the cut aptitude are not solved at all.

  Further, the mat mount is used for a completely different purpose from the white paperboard used for a cardboard liner or a packaging box which is a thick paper having the same basis weight, and thus different processing is performed. For this reason, even if a cardboard liner or white paperboard is used as the mat mount, the problems of curl aptitude and cut aptitude as described above have not been solved.

JP 2003-171895 A

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a mat mount excellent in curling suitability and cut suitability, and a mat board formed using the mat mount. It is in.

The object of the present invention is a multilayer board having a thickness of 700 to 1,200 μm, which is used in a mat board for framing and has a surface layer, a back surface layer, and an intermediate layer between the surface layer and the back surface layer. A paper mat mounting, the freeness of the surface layer is 10 ml or more higher than the freeness of the intermediate layer, and at least the surface of the surface layer is coated or impregnated with a water-soluble polymer, The surface layer is achieved by providing a mat mount having a water absorption of 10 to 60 g / m ² based on JIS-P8140.

  Moreover, the said objective of this invention is achieved effectively by providing the mat | matte board | substrate characterized by containing 2-10 mass% of fillers in the said surface layer.

The above-mentioned object of the present invention can be achieved more effectively by providing a mat backing characterized in that the back layer has a water absorption of 200 to 2,000 g / m ² according to JIS-P8140. .

  Further, the above object of the present invention is achieved more effectively by providing a mat mount characterized in that at least the density of the surface layer is adjusted to be 3% or more higher than the density of the intermediate layer. The

  Furthermore, the object of the present invention is to provide a mat board for framing, which is formed by bonding a surface material to the mat mount according to any one of claims 1 to 4. This is achieved more effectively.

According to the mat mount according to the present invention, the freeness of the surface layer is made 10 ml or more higher than the freeness of the intermediate layer, and the water-soluble polymer is provided on at least one surface of the surface layer or the back surface of the back layer. Furthermore, since the water absorption of the coated surface of the water-soluble polymer is set to 10 to 60 g / m ² , the curl suitability and the cut suitability are excellent, and the balance between both suitability is also excellent. .

  Further, by containing 2 to 10% by mass of filler in the surface layer, curl suitability and cut suitability can be obtained in a more balanced, efficient and stable manner.

Moreover, curl aptitude can be made more favorable by making the water absorbency by JIS-P8140 of the non-coating surface of water-soluble polymer into 200-2,000 g / m < ² >.

  Furthermore, since the density of the surface layer is adjusted to be 3% or more higher than the density of the intermediate layer, it is more excellent in cut suitability and can suppress the occurrence of fluff and paper dust during inclined cutting.

  The mat mount and mat board according to the present invention will be described in detail below with specific examples.

  The mat mount according to the present invention is manufactured by multilayer paper making so as to have three paper layers, a front surface layer, an intermediate layer, and a back surface layer. The mat mount according to the present invention is not limited to such a three-layer structure, and may be a four-layer structure having a plurality of intermediate layers or a multilayer structure having five or more paper layers.

  Here, the multi-layer papermaking is because the composition of the raw material of each layer can be made freely, so that the curl aptitude and the cut aptitude required for the mat mount according to the present invention can be easily obtained. That is, for example, virgin pulp is used for the surface layer and the back layer where cosmetics are required, and waste paper pulp is used for the intermediate layer, and the freeness is adjusted in each of the surface layer, the intermediate layer, and the back layer. In addition, it is easy to adjust the amount of each layer. Therefore, there is an advantage that the curl suitability and the cut suitability required for the mat mount according to the present invention can be easily achieved, and the quality of the mat mount can be ensured while using waste paper pulp that contributes to recycling.

  In addition, since the mat mount has a high basis weight, there is also an advantage that high productivity can be obtained by using multilayer papermaking. That is, when a mat substrate having a high basis weight is manufactured as a single layer, the dehydrating property and drying property of the paper machine are extremely poor, and the production speed is lowered, so that the productivity is lowered. Although it is possible to obtain a mat substrate having a high basis weight by laminating a single-layer paper later, a laminating process is required separately from the production of the single-layer paper, resulting in poor production efficiency.

  Here, as the raw material pulp used for each layer of the mat mount according to the present invention, for example, hardwood bleached kraft pulp (LBKP), softwood bleached kraft pulp (NBKP), hardwood unbleached kraft pulp (LUKP), softwood unbleached kraft pulp (NUKP), hardwood semi-bleached kraft pulp (LSBKP), softwood semi-bleached kraft pulp (NSBKP), chemical pulp such as hardwood sulfite pulp, conifer sulfite pulp, stone grand pulp (SGP), pressurized stone grand pulp (PGW), Refiner Grand Pulp (RGP), Chemi Grand Pulp (CGP), Grand Wood Pulp (GP), Thermomechanical Pulp (TMP), Chemithermo Mechanical Pulp (CTMP), etc. Mechanical Pulp, Tea Wastepaper, Kraft Envelope Wastepaper, Magazine Wastepaper, Old newspaper, flyer , Waste office paper, corrugated paper, upper white waste paper, Kent waste paper, imitation waste paper, ground waste waste paper, etc., disaggregation waste paper pulp, disaggregation / deinking waste paper pulp, or disaggregation / deinking / bleached waste paper pulp, or kenaf, One or several kinds of well-known various pulps such as pulps chemically or mechanically produced from non-wood fibers such as hemp and straw can be appropriately selected and used.

  However, the surface layer of the mat mount is an important layer in order to achieve a balanced and efficient curl suitability and cut suitability in the present invention, since the blade enters the blade first when performing inclined cutting. is there. In the present specification, “excellent curl aptitude” means that the mat board configured as described later does not curl, and “excellent cut aptitude” means that there is no flaking during inclined cutting described later. It is.

  That is, the mat mount according to the present invention is coated or impregnated with a moisture-rich paste on the surface of the surface layer of the mat mount (hereinafter simply referred to as “surface”), similarly to the conventional mat mount, A surface material such as high-quality watercolor paper, Japanese paper, colored paper, or embossed paper is pasted and cut to a predetermined size according to the forehead or the size of the work to form a mat board. In the following, the case where the surface material is bonded to the surface of the mat mount will be described, but the surface material is bonded to the surface opposite to the surface (that is, the surface of the back surface layer) by reversing the layer structure. You can also

  In the present invention, the blade is cut at an angle of about 45 degrees with respect to the surface of the mat board formed in this way (hereinafter referred to as “inclined cut” in this specification), and the work is made. It is assumed that a hollow window portion corresponding to the size is provided. And it is assumed that the cut surface of the mat board after the inclined cut is used as a part of the forehead to produce the work more effectively.

  For this reason, LBKP and NBKP are particularly preferably used for the raw material pulp of the surface layer, among the raw material pulps described above.

  In particular, the raw material pulp of the surface layer preferably contains 30 to 70% by mass of LBKP, and more preferably contains 30 to 50% by mass. When the content of LBKP is 30 to 70% by mass, the water-soluble polymer coated and impregnated on the surface of the mat mount according to the present invention described later can be effectively kept on the surface, curling suitability and cut It is possible to improve the fitness while keeping a good balance.

  If the content of LBKP is less than 30% by mass, uneven formation occurs and it becomes difficult to obtain a good texture. Therefore, the coating properties of the water-soluble polymer coated / impregnated on the surface, coating / impregnation The amount of variation is likely to occur, and the intermediate layer (hereinafter simply referred to as “intermediate layer”) is a layer adjacent to the surface layer, which is used when the surface material is bonded (hereinafter simply referred to as “glue”). ), The adhesive permeation unevenness occurs, and the curl aptitude is reduced. In addition, when uneven formation occurs, density unevenness also partially occurs, but when the window is provided by cutting perpendicularly to the surface of the mat mount, the blade enters with high pressure in the vertical direction, Even if there is density unevenness, the cut surface will not generate flaws, but when performing inclined cutting as in the present invention, the unevenness of density tends to generate flaws on the cut surface, and the cut suitability is improved. descend.

  Moreover, it is preferable to contain 20-50 mass% of NBKP in the raw material pulp of a surface layer, and it is more preferable to contain 30-45 mass%. By adding 20 to 50% by mass of NBKP in addition to LBKP to the raw material pulp of the surface layer, curl suitability and cut suitability can be obtained in a more balanced, efficient and stable manner.

  That is, by adding a predetermined amount of thick and rigid NBKP to the raw material pulp of the surface layer, moderate voids can be generated in the surface layer. Thereby, since this space | gap absorbs glue, the pulp fiber of a surface layer does not absorb glue, and since swelling of a fiber can be prevented, curl aptitude can be improved.

  NBKP has a long fiber length and is rigid. Accordingly, when the NBKP content exceeds 50% by mass, it is difficult to obtain a good texture, so that the coating properties of the water-soluble polymer coated / impregnated on the surface and the coating / impregnation amount tend to vary. At the same time, since the paste easily penetrates into the intermediate layer, the penetration unevenness partially occurs, and the curl suitability is lowered. Further, due to partial density unevenness caused by uneven texture, cut suitability is reduced, and when an inclined cut is performed, the cut surface is liable to be chipped.

  Furthermore, it is preferable to contain 5-50 mass% of mechanical pulp in the raw material pulp of the surface layer, and it is more preferable to contain 10-30 mass%. Note that, as described above, the mat mount according to the present invention is intended to enhance the effect of the work by using the cut surface after the inclined cut as a part of the forehead. Among them, it is preferable to use TMP or PGW that generates less binding fibers and paper dust.

  By adding 5 to 50% by mass of mechanical pulp to the raw material pulp of the surface layer in addition to LBKP and NBKP, high cushioning properties can be imparted to the surface layer, and cut suitability can be improved. In other words, the cushioning property by mechanical pulp, which is not found in LBKP and NBKP, can reduce unevenness of formation and unevenness of density, etc., so that it is possible to improve the cutting suitability. Occurrence can be prevented.

  When the content of mechanical pulp exceeds 50% by mass, the bond between fibers decreases and the strength decreases, so that paper dust is generated from the cut surface after the inclined cut, and there is a problem of delamination from the intermediate layer. May occur. When delamination occurs, some delamination occurs between the layers of the mat mount, so the cut surface after the slant cut becomes unsightly, making it impossible to produce the work effectively, and commercial value as a mat mount Will fall.

  Further, the raw pulp used for the surface layer has a freeness of 10 ml or more, preferably 20 to 100 ml higher than that of the raw pulp of the intermediate layer.

  Thus, when the freeness of the raw material pulp of the surface layer is relatively higher than the freeness of the intermediate layer adjacent to the surface layer by 10 ml or more, the curl aptitude is excellent.

  In addition, when the freeness of the surface layer becomes relatively higher than 100 ml than the freeness of the intermediate layer, the entanglement of the pulp fibers of the surface layer and the intermediate layer becomes worse. The delamination may occur due to the pressure applied by the insertion.

  The freeness of the raw pulp used for the surface layer is preferably 250 to 450 ml, more preferably 300 to 400 ml.

  Further, the freeness of the raw material pulp of the intermediate layer is preferably 230 to 430 ml, and more preferably 280 to 380 ml.

  When the freeness of the intermediate layer is less than 230 ml, the fiber length becomes short, so that it becomes difficult to generate voids in the intermediate layer. For this reason, since the pulp fiber absorbs the moisture of the paste and swells, curling ability is lowered and curling is likely to occur.

  On the other hand, if the freeness of the intermediate layer exceeds 430 ml, curl suitability can be improved in that the voids are likely to be generated in the intermediate layer, but coating irregularity of the water-soluble polymer is likely to occur. Since the occurrence of curling increases, the curl suitability is lowered as a result. In addition, since the bond between fibers is reduced and the strength is reduced, cut suitability is lowered, and there are cases where delamination occurs or paper dust is likely to be generated from the cut surface after inclined cutting. is there.

  The “freeness” in this specification refers to a Canadian standard freeness tester according to JIS-P8121, after the sample pulp is disaggregated with a standard disintegrator according to JIS-P8220. The freeness value measured in (1).

  Moreover, it is preferable not only to adjust the freeness of the raw material pulp of each layer, but also to set the average fiber length of the pulp fiber of the entire mat mount to 1.0 to 2.0 mm, and to 1.2 to 1.8 mm More preferably.

  That is, in the case of the mat mount according to the present invention, it is preferable to use a beating method that promotes fibrillation of fibers in order to improve the entanglement between fibers, but depending on the beating method, the fibers are simply not fibrillated. Cutting may be performed by cutting fibers, and even in such a case, the apparent freeness changes. For this reason, it is preferable to adjust the length of a pulp fiber to 1.0-2.0 mm as the whole mat | matte mount together with adjustment of the freeness of the raw material pulp of each layer.

  Since the mat mount according to the present invention is formed by multilayer papermaking, different raw pulps can be used for the front layer, the intermediate layer, and the back layer as described above.

  However, the mat mount according to the present invention assumes that the work is rendered more effectively by using the cut surface after the inclined cut as a part of the forehead as described above. For this reason, even if different raw pulps are used for each layer of the mat mount according to the present invention, it is preferable to adjust the raw pulps of the respective layers to substantially the same color so that the cut surface after the inclined cut does not become a striped pattern.

  The term “substantially the same color” as used herein refers to a range in which the cut surface is not visually striped. Specifically, after peeling the mat mount to each layer, the lightness (L), hue (a), and hue (b) of each layer are measured in accordance with JIS-Z8722, and the difference in color tone between adjacent layers (ΔE ) Is preferably within 1.5, and more preferably within 1.0.

ΔE can be obtained by the following equation, where (a1−a2) is Δa, and similarly ΔL and Δb, where the a value of the surface layer is a1 and the a value of the intermediate layer adjacent to the surface layer is a2. .
ΔE = (Δa ² + Δb ² + ΔL ² ) ^1/2
The difference in color tone between the intermediate layer and the back layer can be obtained in the same manner.

  Moreover, in the raw material pulp or pulp slurry of each layer, for example, chemical fixing agents such as sulfuric acid bands, sizing agents such as rosin, paper strength enhancing agents such as polyacrylamide and starch, drainage / yield improving agents such as polyamide Add water-resistant agents such as polyamide, polyamine, epichlorohydrin, antifoaming agents, basic dyes, acid dyes, anionic direct dyes, cationic direct dyes, and other internal chemicals as necessary. Can do.

  In particular, calcium carbonate, zinc oxide, aluminum hydroxide, zinc sulfide, titanium dioxide, calcium sulfate, calcium sulfite, and sulfuric acid are used for the raw material pulp of the surface layer and / or intermediate layer within the range that does not impair the effect of improving curl suitability and cut suitability. It is preferable to contain fillers such as barium, talc, clay and silica alone or in combination.

  Moreover, it is preferable to make these fillers contain 2-10 mass% with respect to the raw material pulp of each layer, and it is more preferable to contain 2-8 mass%. Thereby, curl suitability and cut suitability can be obtained in a balanced manner, efficiently and stably.

  When the filler content is less than 2% by mass, it is difficult to obtain an effect of improving the curl aptitude by the filler. On the other hand, when it exceeds 10% by mass, the curl aptitude can be improved. It tends to occur.

  Among the fillers described above, talc and clay can be preferably used from the viewpoint of cost. Moreover, since the mat | matte mount based on this invention also requires the preservability of a work, it is preferable to manufacture in a neutral area | region and a calcium carbonate can be used conveniently for this.

  As the sizing agent, various known ones can be used. In particular, in the present invention, there is a size development effect in a neutral region such as a neutral rosin sizing agent, an AKD sizing agent, and an ASA sizing agent. Using a high sizing agent and a hot water extraction pH value of 6.5 to 9.0, preferably 6.5 to 8.5, it is preferable because the mat backing is produced in a neutral region because of excellent storage stability.

  The blending amount of the sizing agent is preferably 0.2 to 1.5% by mass in terms of solid content with respect to the raw material pulp of each layer. When the blending amount of the sizing agent is less than 0.2% by mass, there is little effect of imparting the desired water absorption described later on the front surface and / or the back surface, while the blending amount is more than 1.5% by mass. The effect of the water absorption applied to the front surface and / or the back surface is not changed, and only the production cost is increased.

  When the matte mount has a hot water extraction pH value in the range of 6.5 to 9.0, more preferably 6.5 to 8.5, and the pH value is as close to 7.0 as possible, a long time elapses. However, there is little discoloration and excellent storage stability.

  The pH can be adjusted with acid chemicals such as sulfuric acid, hydrochloric acid and aluminum sulfate, and alkaline chemicals such as sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium hydrogen carbonate, sodium carbonate, sodium hydrogen phosphate, and aqueous ammonia. it can. Among these alkaline chemicals, it is preferable to use sodium hydrogen carbonate that does not affect discoloration or the like on works such as photographs and paintings and has excellent storage stability.

  Thus, by selecting and adjusting the raw material pulp of the surface layer, adjusting the freeness, etc., the mat backing according to the present invention has a peel strength measured according to the peel strength test of TAPPI UM 522 of 0.5 to 1. The pressure can be adjusted to 5 MPa, preferably 0.6 to 1.2 MPa. Thereby, delamination does not occur even when the inclined cut is performed.

  Adjustment of peel strength can also be achieved by adjusting the amount of each layer to be described later, adding a paper strength enhancer, or spraying an adhesive such as starch between the layers.

With the amount of the surface layer is preferably 40 to 120 g / ^{m 2,} and more preferably 45~100g / ^{m 2.}

When the amount of the surface layer is less than 40 g / m ² , even if the raw pulp is mixed, the drainage degree, the water absorption, etc. are adjusted, the amount of attachment is small, so the curling ability and the cutting ability desired by the present invention. Can't get.

On the other hand, when the amount of the surface layer exceeds 120 g / m ² , the curl aptitude is lowered and the manufacturing cost is increased. That is, expensive pulp is often used for the surface layer as compared to the pulp used for the intermediate layer and the back layer. However, as the amount of application increases, the amount of the expensive pulp used increases. The manufacturing cost of the base paper increases. Furthermore, since the thickness of the surface layer increases as the amount of the surface layer increases, the water absorption imparted to the back surface layer, which will be described later, becomes difficult to exhibit. It cannot be made small, and the curl suitability is lowered.

The mat mount according to the present invention varies depending on the size of the forehead on which the mat mount is used and the purpose of use, but the thickness may be 700 to 1,200 μm and the basis weight may be in the range of 430 to 750 g / m ^2. preferable.

When the thickness of the mat mount is less than 700 μm and the basis weight is less than 430 g / m ² , the strength and rigidity as the mat mount are insufficient, and it is difficult to use for the frame. On the other hand, even when the thickness of the mat mount is larger than 1,200 μm or when the basis weight is larger than 750 g / m ² , the curl suitability and the cut suitability cannot be improved, resulting in excessive quality. At the same time, the manufacturing cost only increases.

  The mat mount according to the present invention formed using the raw material pulp as described above is coated / impregnated with a water-soluble polymer on at least the surface (in this embodiment, the surface of the mat mount) to which the surface material is bonded. Is done.

  As the water-soluble polymer, one or more water-soluble polymers can be used from starch, polyvinyl alcohol (PVA), polyacrylamide (PAM) and the like. Among these, it is preferable to use polyvinyl alcohol (PVA) from the viewpoint of adhesiveness with glue, dimensional stability at the time of glue adhesion / drying, cut suitability, and the like.

The content of the water-soluble polymer for coating and impregnating the surface, it is preferable to one surface per 0.25~2.0g / ^{m 2} in terms of solid content, and 0.25~1.5g / ^{m 2} It is more preferable.

When the water-absorbing polymer content is less than 0.25 g / m ² , the water absorption of the coated surface on which the water-soluble polymer is coated / impregnated is 10-60 g / m ² as described above. The paste easily penetrates into the surface layer, and the curl suitability decreases.

On the other hand, if the content of the water-soluble polymer exceeds 2.0 g / m ² , the coating suitability deteriorates due to an increase in viscosity at the time of coating / impregnation of the water-soluble polymer, causing wrinkles / stains, The problem becomes more likely to occur. Moreover, the drying property after coating and impregnation is deteriorated, and the productivity is lowered. Although there is a method of internally adding a water-soluble polymer to the surface layer, it is preferable to add it externally from the viewpoint of cost and operability.

  The coating apparatus used for coating / impregnating the water-soluble polymer is not particularly limited. For example, an air knife coater, a blade coater, a rod coater, a bar coater and a gate roll coater, a roll coater such as a size press, a velbapa coater Calendar coating or the like can be used as appropriate.

  After coating and impregnating the water-soluble polymer, it is preferable to smooth the front and back surfaces of the mat mount with a calendar device.

  The calendar device for performing the surface smoothing treatment is not particularly limited, and for example, a machine calendar, a soft calendar, a Yankee dryer, or the like is used as appropriate. The surface smoothing treatment is smoothness when the backing of the clamping device is measured as 1.0 MPA using a soft backing in accordance with the JIS-P8151 print surf tester method (area type flow meter type print surf tester). Is preferably 3.0 to 8.0 μm because the surface material can be flatly bonded without unevenness.

Thus, the surface layer coated with and impregnated with the water-soluble polymer (hereinafter referred to as “coated surface”) has a water absorption measured in 2 minutes based on JIS-P8140 (hereinafter referred to as “water absorption”). referred to as ".) is preferably a 10 to 60 g / ^{m 2,} and more preferably a 20 to 50 g / ^{m 2.}

When the water absorption of the surface layer is less than 10 g / m ² , the adhesive does not penetrate into the paper layer of the surface layer and the adhesiveness is deteriorated. Therefore, a special adhesive is required, and the mat according to the present invention The solubility also deteriorates when the mount is recycled as used paper. Moreover, in order to make a water absorbency less than 10 g / m < ² >, it is necessary to add a lot of chemical | medical agents, As a result, operativity deteriorates and manufacturing cost becomes high.

On the other hand, when the water absorption exceeds 60 g / m ² , the paste penetrates into the paper layer of the surface layer, and the pulp fiber swells due to the moisture of the paste and then curls easily by drying. Further, since the adhesiveness is deteriorated, a problem that a large amount of adhesive has to be applied arises, and curling is more likely to occur.

Moreover, it is preferable that the water absorption of a back surface layer is 200-2,000 g / m < ² > measured in 2 minutes of measurement time based on JIS-P8140, and is 200-1,500 g / m < ² >. And more preferred. Thereby, since a back surface layer becomes a layer excellent in water absorption, it can make the curl aptitude of a mat | matte mount more favorable.

  That is, the surface material must be bonded and a certain amount must be infiltrated into the surface layer in order to ensure the adhesive strength while leaving the glue on the coated surface in order to ensure curl suitability.

  However, when the paste is infiltrated into the surface layer, the moisture in the surface layer and the moisture in the back layer are greatly different. When such a mat mount is dried, curling occurs due to a difference in moisture between the front surface layer and the back surface layer, and curling aptitude decreases.

  For this reason, by adjusting the water absorption of the back surface, that is, the surface to which the surface material is not bonded, to the above range and absorbing moisture such as glue that has penetrated into the inside of the surface layer to the back layer, the surface layer, intermediate The moisture content of the moisture inside each layer of the layer and the back layer is made closer to each other. Thereby, it can be set as the mat | matte mount which is excellent also in the curl aptitude, without impairing the bonding aptitude with the surface raw material of a surface layer.

If the water absorption of the back surface layer is less than 200 g / m ² , the water absorption of the back surface layer is low, and moisture such as glue that has penetrated into the inside of the surface layer cannot be absorbed by the back surface layer. The difference in moisture between the layer and the back layer cannot be reduced, and the curl suitability is lowered.

On the other hand, if the water absorption exceeds 2,000 g / m ² , the paste component may penetrate to the back surface. For example, mat boards are stacked at the time of storage or transportation, but when a mat mount in which the paste component has permeated the back surface is used in this way, the paste component that has penetrated is adjacent when stacked. There is a possibility that problems such as transfer to the mat board and adhesion will occur.

In order to adjust the water absorption of the back surface to 200 to 2,000 g / m ² , a method in which no sizing agent is added, a small amount of sizing agent is added, or a surfactant is added to increase water absorption. Can be achieved.

  In addition, when mix | blending a sizing agent, the compounding quantity of the sizing agent is less than 0.1 mass% in conversion of solid content with respect to the raw material pulp of a back surface layer. When the blending amount of the sizing agent exceeds 0.1% by mass, the effect of imparting the water absorption desired by the present invention to the back layer is lowered, and the curl suitability of the mat mount is lowered.

  Further, the mat mount according to the present invention, as described above, by selecting the raw material pulp, adjusting the blending ratio and the freeness, adjusting the amount of each layer, coating and impregnation of a water-soluble polymer, It is preferable to adjust so that the density of the surface layer is higher than the density of the intermediate layer.

  Even if the overall density of the mat mount is the same, the mat mount with the surface layer density adjusted higher than the density of the intermediate layer can greatly suppress the occurrence of fluff and paper dust during inclined cutting. As a result of experiments by the present inventors, it was found.

  Specifically, the ratio (%) of the surface layer density to the intermediate layer density (surface layer density / intermediate layer density × 100) is preferably 3% or more, and more preferably 5% or more. More preferably, 8% or more is most preferable.

  When adjusted to 4% or more, the effect of suppressing fluff and paper dust at the time of inclined cutting appears. Further, when the content is 8% or more, a more remarkable effect can be obtained, but even if the content is further increased, the effect of suppressing blemishes and paper dust remains flat.

  The mat mount according to the present invention configured as described above is excellent in curl aptitude, extremely unlikely to curl, excellent in cut aptitude, and extremely unlikely to cause fluff, so that a window is effectively provided. be able to.

  Further, the mat board for framing formed by using the mat mount according to the present invention is excellent in adhesion between the glazing and the mat board, and the adhesion between the mat board and the work, and is an effective production of the work contained in the forehead. Also excellent.

  In order to confirm the effect of the mat mount according to the present invention, various samples as described below were prepared, and a test for evaluating the quality of each sample was performed. In the present embodiment, the present invention is not limited, and it is needless to say that the configuration can be appropriately changed without departing from the scope of the claims.

  21 types of mat mounts according to the present invention (referred to as “Example 1” to “Example 21”) and 5 types of mat mounts for comparison with these Examples 1 to 21 (this) ("Comparative Example 1" to "Comparative Example 5") having the structure shown in Table 1, a commercially available white liner (referred to as "Comparative Example 6"), and a commercially available mat mount. (This is referred to as “Comparative Example 7”) and evaluated.

[Example 1]
For the surface layer, Canadian standard when pulp slurry comprising 40% by mass of softwood bleached kraft pulp (NBKP), 40% by mass of hardwood bleached kraft pulp (LBKP), and 20% by mass of thermomechanical pulp (TMP) is disintegrated after paper making. To what was adjusted so that the freeness (CSF) became 350 ml, sizing agent (R50 made by Modern Chemical Industry Co., Ltd.) was 0.25 mass% in terms of solid content, PAM (made by Harima Chemicals Co., Ltd., Hermide B 15) is internally added in an amount of 0.15% by mass in terms of solid content, talc is internally added as a filler so that the ash content is 5%, and sodium bicarbonate is added to obtain a hot water extraction pH value of 7.5. The raw material adjusted as described above was used.

  About the back surface layer, it adjusted similarly to the surface layer except not having added the sizing agent.

  As the intermediate layer (2-4 layers), PAM (harima) was prepared by adjusting a pulp slurry comprising NBKP 30% by mass, deinked waste paper pulp (DIP) 50% by mass, and TMP 20% by mass so that the CSF becomes 340 ml. Kasei Co., Ltd., Hermide B-15) is added internally by 0.5% by mass in terms of solid content, talc is internally added as a filler so that the ash content is 5%, and sodium bicarbonate is added to extract with hot water A raw material adjusted to have a pH value of 7.5 was used.

The raw material for each of these layers is a circular multi-layer paper machine, the surface layer weight is 80 g / m ² , the middle layer (2-4 layers) is 460 g / m ² , and the back layer weight is 80 g / m 2. ² and a 6-layer structure, PVA (Nippon Synthetic Chemical Co., Ltd., Gohsenol N300) is calendered on the surface (surface layer surface) coating amount of 1.0 g / m ² , back surface (back surface layer) 1.0 g / m ^{2 was} applied to the back of the mat to obtain a mat mount (Example 1) having a basis weight of 620 g / m ² and a thickness of 1,000 μm.

[Examples 2 to 6]
Except that water-soluble polymer (coating agent) is not applied to the back side, and the amount of water-soluble polymer (PVA) applied to the surface is adjusted to the values shown in Table 1. Is a mat mount obtained in the same manner as in Example 1.

[Examples 7 to 9]
A mat mount obtained in the same manner as in Example 1 except that the ash content of the surface layer and the intermediate layer was adjusted to the values shown in Table 1.

[Examples 10 to 15]
The CSF of the raw material pulp used for the intermediate layer was adjusted to the value shown in Table 1, the coating amount of the water-soluble polymer (PVA) applied to the back surface was adjusted to the value shown in Table 1, and the surface A mat mount obtained in the same manner as in Example 1 except that the water absorption was adjusted to the values shown in Table 1.

[Examples 16 to 21]
Except that the CSF of the raw material pulp used for the surface layer and the intermediate layer was adjusted to the values shown in Table 1 and the water absorption on the back surface was adjusted to the values shown in Table 1, the other points were the same as in Example 1. Matte mount obtained.

[Comparative Example 1]
A mat mount obtained in the same manner as in Example 1 except that the water-soluble polymer (PVA) was not applied to the front and back surfaces.

[Comparative Examples 2-3]
Matte mount obtained in the same manner as in Example 1 except that the basis weight, the ash content of the surface layer and the intermediate layer were changed to the values shown in Table 1, and the thickness was changed to the values shown in Table 2.

[Comparative Examples 4 to 5]
A mat mount obtained in the same manner as in Example 1 except that the CSF of the intermediate layer and the water absorption of the surface were changed to the values shown in Table 1.

[Comparative Example 6]
White liner for general cardboard that is commercially available.

[Comparative Example 7]
A common mat mount available on the market.

  The “mixing ratio (mass%) of raw material pulp” in Table 1 means that each sample is subjected to layer peeling described later, and the fiber ratio of the surface layer is JIS-) 8120 “Paper, paperboard and pulp fiber composition” It is a value measured according to “Test method”.

  The delamination is performed according to the following procedure. First, each sample obtained from each sample is immersed in water at room temperature for about 1 hour. Each sample immersed in water is rubbed on a round bar of about 10 mmΦ starting from a corner, and then the round bar is rolled to squeeze each sample. This operation is repeated starting from all four corners of each sample, and the ironing force is applied to the sample from each direction. As a result, a part of the layers of each sample is peeled off, and this is used to separate the surface layer, the middle layer, and the back surface layer to perform layer peeling.

“Freeness (ml)” means that the sample after delamination described above is cut into a size of about 3 cm ² to obtain a test piece having a weight of about 25 g. After soaking for 24 hours, it was disaggregated for 15 minutes with a standard disaggregator according to JIS-P8220. After confirming that the test piece was completely disaggregated, it was Canadian standard according to JIS-P8121. It is a value measured with a freeness tester.

Further, the “water absorption (g / m ² )” is a value measured based on “paper and paperboard—water absorption test method—Cobb method” described in JIS-P8140 with a water absorption time of 2 minutes.

  For all these Examples and Comparative Examples, physical properties of basis weight, thickness, density, water absorption, and peel strength are measured, and cut suitability, curl suitability, rendering effect, pasting suitability, and productivity are evaluated. The results of the tests performed were as shown in Table 2. This physical property measurement and evaluation test were performed under environmental conditions of a temperature of 23 ° C. ± 1 ° C. and a humidity of 50 ± 2% in accordance with JIS-P8111.

“Basis weight (g / m ² )” in Table 2 is the total grammage of each sample, that is, the entire mat mount, and conforms to “paper and paperboard—basis weight measurement method” described in JIS-P8124. It is the value measured.

  The “thickness (μm)” is the thickness of the entire mat mount, and is a value measured according to “Paper and paperboard—Test method of thickness and density” described in JIS-P8118.

“Density (g / cm ³ )” means that the above-described layer peeling is performed, and a surface layer and an intermediate layer (remaining layers excluding the surface layer and the back layer) are collected from each sample. This is a value calculated by measuring the applied amount and thickness of the intermediate layer. Further, in order to eliminate measurement errors, 10 samples were prepared from each sample and measured, and the thickness was measured by performing N number 20 or more for each sample and excluding the maximum and minimum values. .

  In the case of density measurement, the layer peeling is basically performed in the same manner as the layer peeling described above, but the samples obtained from the respective samples were performed without being immersed in water.

  “Peel strength (MPA)” is a value obtained by measuring the peel strength in the Z-axis direction according to TAPPI UM522.

  “Cut aptitude” means that each sample is subjected to an inclined cut and provided with a hollow window portion, and the state of the cuts generated on the inclined cut cutting surface is visually evaluated. The average evaluation of 10 samples. It is. The evaluation criteria are: ◎ marked “Liquid biting”, ○ Marked “Slightly biting, but significant improvement effect”, Δ There were four stages: “not so much” and “marked with a lot of scars, resulting in product defects”.

  “Curlability” is a visual evaluation of the state of curling of a mat board formed by bonding a surface material to the surface of the surface layer of each sample, which is a mat mount, and drying. The evaluation criteria are: ◎ marked “almost no curling”, ◯ mark “curling is somewhat, but the improvement effect is remarkable”, △ mark “curl is generated and the improvement effect is There are four levels, “not much” and “same level as mat mounts that are frequently curled, with a lot of curls”.

  “Directional effect” means that after a surface material is bonded to the surface of the surface layer of each sample, which is a mat mount, an inclined cut is made on each sample to provide a hollow window, and this inclined cut cutting surface is used. This is a visual evaluation of the effect of the work stored in the forehead, and is an average evaluation of 10 samples. The evaluation standard is “◎”, “There is almost no flaking on the cut surface, and there is almost no layer separation (layer separation). , ○ mark “Generation of flakes and delamination is somewhat, but the production effect of the work is good”, Δ mark “Generation of flakes and delamination is present, and there is not much production effect of the work” The four marks were marked with “×”, “Generation of blemishes and layer peeling, almost no effect in the production of the work, and the same level as a mat mount currently on the market”.

  “Adhesion suitability” refers to the adhesiveness with the surface material pasted on the surface of the surface layer of each sample, and the degree of penetration of moisture such as glue applied and impregnated during pasting to the back of each sample This is a comprehensive evaluation of the suitability for bonding. The evaluation criteria are: “Excellent bonding suitability” marked with “◎”, “There is no problem with pasting suitability” marked with ○, “Same level as currently available mat mounts” There were four stages: “not much improved” and “poor suitability”.

  In addition, “productivity” was evaluated as the productivity when a test paper was made on a mat mount under each manufacturing condition using a paper machine.

The evaluation criteria are: ◎ marked “same as or better than currently marketed mat mount”, ○ marked “productivity may be reduced compared to currently marketed mat mount”, Δ mark “Productivity is reduced by about 1 to 4% compared to the currently available mat mount”, “X” indicates that productivity is reduced by 5% or more compared to the currently available mat mount. 4 levels.

As can be seen from Table 2, the mat mount according to the present invention, that is, the mat mount according to Examples 1 to 21, is excellent in curl suitability and cut suitability, and has a high effect of producing a work housed in the forehead. It can be seen that it is excellent in bonding suitability and productivity.

It is a schematic sectional drawing which shows the structure of a general forehead. It is a schematic sectional drawing which shows the structure of a mat board.

Explanation of symbols

1 frame 2 frame 3 work 4 glazing 5 mat board 6 mount board 7 back board 8 space formed between the glazing and the mat board 9 mat mount 10 surface material 11 hollow window portion 12 cut surface

Claims (5)

It is a mat board for multi-layered paper having a thickness of 700 to 1,200 μm, which is used for a mat board for framing and has a surface layer, a back surface layer, and an intermediate layer between the surface layer and the back surface layer. And
The freeness of the surface layer is 10 ml or more higher than the freeness of the intermediate layer,
At least the surface layer is coated or impregnated with a water-soluble polymer,
The surface of the surface layer has a water absorption of 10 to 60 g / m ² based on JIS-P8140. The mat mount according to claim 1, wherein at least the surface layer contains 2 to 10% by mass of filler. The mat backing according to claim 1 or 2, wherein the back surface of the back surface layer has a water absorption of 200 to 2,000 g / m ² according to JIS-P8140. The mat mount according to any one of claims 1 to 3, wherein the density of at least the surface layer is adjusted to be 3% or more higher than the density of the intermediate layer. 5. A mat board for framing, which is formed by bonding a surface material to the surface of the mat mount according to any one of claims 1 to 4.