JP4707908B2 - Embedding dish - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an embedding dish in which a specimen such as a cut human body tissue is cast with a casting material such as paraffin.
[0002]
[Prior art]
When a specimen such as a human tissue is observed with a microscope, the specimen is first subjected to processing such as drug processing using a specimen processing container called a cassette. For a summary of drug processing and a specific example of a cassette, see Japanese Patent Application No. 11-296806 (Japanese Patent Application Laid-Open No. 2001-116670) by the same applicant as the present application.
[0003]
The specimen that has been subjected to the chemical treatment or the like is cast into paraffin using a mold called an embedding dish, and then sliced together with the paraffin into thin pieces and used for microscopic observation. The specific procedure will be described below with reference to FIG.
[0004]
First, as shown in FIG. 1A, the embedding dish 100 is placed on a suitable table (not shown), the specimen S is accommodated in the cavity 101 of the embedding dish 100, and the embedding dish 101. Place the cassette 120 on top. Then, molten paraffin P is poured from above the cassette 120. A plurality of holes 121 are formed in the bottom wall of the cassette 120, and the paraffin P fills the cavity 101 of the embedding dish 100 through the holes 120. Next, the embedding plate 101 is placed on the cooling plate 140 in the state as it is. The paraffin P is deprived of heat by the cooling plate 140 and outside air and solidifies. At this time, the paraffin P existing in the cavity 101 of the embedding dish 100 is combined with the paraffin P existing in the cassette 120 via the paraffin P existing in the hole 120 of the cassette 120. Are integrated (the casting process).
[0005]
Next, as shown in FIG. 1B, the cassette 120 is removed from the embedding dish 100. The substantially truncated pyramid-shaped paraffin block P1 is firmly attached to the bottom surface of the removed cassette 120 (the mold removing step).
[0006]
Next, as shown in FIG. 1 (c), the paraffin block P1 is arranged so that the range of about 2 mm from the tip of the paraffin block P1 has a prismatic shape having a predetermined cross-sectional shape (shape dimension suitable for being placed on the slide). Shaving and removing unnecessary paraffin P2 that interferes with subsequent processes (the shaping / removal process).
[0007]
Next, as shown in FIG. 1D, the tip of the paraffin block P1 is thinly sliced to create a plurality of thin pieces including the specimen S (the slicing step). In the shaping / removing step, the tip of the paraffin block P1 has a prismatic shape because it is inconvenient for subsequent handling if the slices have different sizes. This is to make the shape.
[0008]
The specimen-containing thin piece obtained in this way is placed on a preparation and used for microscopic observation.
[0009]
The functions required for the embedding dish used as described above include the following. (1) The mold can be easily removed. (2) A cast product capable of minimizing the man-hour required for the shaping / removal process can be formed. (3) The molten paraffin must be solidified in a well-balanced manner so that no tearing or the like occurs during solidification. (4) Rapidly solidify molten paraffin.
[0010]
In order to satisfy the above (1), the shape of the cavity of the conventional embedding dish is generally a truncated pyramid shape. In short, by taking a sufficient draft, the part of the paraffin block P1 is easily removed from the embedding dish. However, in this case, the above (2) is not satisfied. That is, if the draft angle is increased, the shaping process described above takes time, so the draft angle is preferably as small as possible.
[0011]
As an embedding dish developed to achieve both (1) and (2) above, it is disclosed in Japanese Patent Application No. 11-296400 (Japanese Patent Application Laid-Open No. 2001-116669) by the same applicant as the present application. There is something. The embedding dish disclosed here separates the bottom wall portion of the cavity and allows the paraffin block to be easily extracted from the embedding dish by extruding the bottom wall after solidification of paraffin. Meet the conflicting requirements of minimizing draft and ease of mold removal. However, it cannot be denied that the embedding dish is composed of two separate parts, which makes the handling somewhat troublesome, makes the storage of parts troublesome, and leads to an increase in manufacturing cost.
[0012]
By the way, conventional embedding dishes are mainly made by press-molding stainless steel. Although stainless steel embedding dishes have the advantage of high durability, stainless steel has a large specific heat and high thermal conductivity (compared to resin), so the above requirements (3) and (4) are not met. There are many problems. First, in the embedding dish made of stainless steel, the poured paraffin immediately starts to solidify, so that uneven casting is likely to occur.
[0013]
In order to prevent this, the preheating of the embedding dish is usually performed before casting, but if this is done, the coagulation time is significantly increased and workability is greatly deteriorated. In addition, when a cooling plate is used to promote cooling, only the portion in contact with the cooling plate is rapidly cooled due to the high thermal conductivity of stainless steel, and internal strain may occur, causing cracks in the paraffin block.
[0014]
In addition, since the stainless steel embedding dish is usually manufactured by press molding, it is difficult to form the cavity part so as to satisfy the above (1) and (2).
[0015]
As described above, since the stainless steel embedding dish has no merit other than the high durability, the embedding dish made of resin has been studied in recent years. However, even if it is not made of stainless steel, there is a problem related to coagulation even in the case of resin, and there is no embedding dish that can satisfy the above (3) and (4) at a level that can be completely satisfied. It is.
[0016]
[Problems to be solved by the invention]
The present invention has been made in view of the above situation, and a first object of the present invention is to easily perform mold removal and to reduce man-hours required for the shaping / removal process after casting. It is to provide an embedding dish that can be used.
[0017]
The second object of the present invention is to provide an embedding dish capable of rapidly solidifying molten paraffin while ensuring casting quality.
[0018]
[Means for Solving the Problems]
In order to achieve the first object, the present invention provides an embedding dish for carrying out an embedding process in which a specimen is cast with a casting material such as paraffin, and has a cavity into which the casting material is injected. Is defined by a bottom wall and a plurality of side walls erected on the periphery of the bottom wall, and the cavity has a cavity lower part on the bottom wall side and a cavity upper part located on the cavity lower part. An angle α formed between an inner surface of a portion of the side wall surrounding the cavity lower portion and an inner surface of the bottom wall is determined by an angle α between the inner surface of the side wall of the portion surrounding the cavity upper portion and the bottom. It is characterized by being smaller than the angle β formed by the inner surface of the wall.
[0019]
In order to achieve the second object, the present invention provides an embedding dish for performing an embedding process in which a specimen is cast with a casting material such as paraffin, and stands on a bottom wall and a peripheral edge of the bottom wall. A plurality of side walls defining a cavity into which casting material is injected together with the bottom wall, and a mounting wall provided around the opening of the cavity and for mounting a base material such as a cassette; The thickness of the bottom wall is smaller than the thickness of the side wall and the mounting wall.
[0020]
In order to integrally mold such an embedding dish by an injection molding method using a resin material, it is possible to slide at least a portion of the mold that forms the bottom wall, and a molten resin is placed in the mold cavity. After filling, it can be easily manufactured by sliding the slidable portion.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0022]
The embedding dish 1 has a placement wall 2 that provides a placement surface 2a on which a specimen processing cassette is placed. An edge wall 3 is erected on the periphery of the mounting wall 2 so as to surround the mounting wall 2.
[0023]
The contour of the peripheral edge of the mounting wall 2 exactly matches the contour of the peripheral edge of the sample processing cassette placed on the mounting wall 2, and a corner connecting the mounting wall 2 and the edge wall 3. The radius of the R portion 4 is also set as small as possible (specifically, about 0.5 mm). Therefore, unnecessary paraffin P2 adhering to the periphery of the cassette as described in the section of the prior art can be minimized.
[0024]
A recess is provided in the center of the mounting wall 2, and this recess becomes a cavity 10 in which a specimen is accommodated when the embedding process is performed. The cavity 10 is partitioned by a bottom wall 11 and a plurality of side walls 12 provided upright on the periphery of the bottom wall 11. Each side wall 12 includes a substantially vertical side wall lower portion 13 and a side wall upper portion 14 that is largely inclined.
[0025]
Legs 20 are provided on both long sides of the embedding dish 1. The height of the lower end of the leg 20 matches the height of the lower surface of the bottom wall 11. The leg 20 and the side wall 12 facing the leg 20 are connected by a rib 21. With this structure, even when molten paraffin is injected into the cavity 10 and the temperature of the embedding dish 1 rises, the rigidity of the embedding dish 1 as a whole is maintained. A plurality of windows 22 are formed in the leg 20. When the molten paraffin is injected into the cavity 10, the window 22 allows the air flow 23 shown in FIG. 3 to flow smoothly and promotes solidification of the molten paraffin.
[0026]
Next, the cavity 10 will be described in detail. In particular, as shown in detail in FIG. 3, the cavity 10 includes a cavity lower part 10 a located on the bottom wall 11 side and surrounded by a plurality of side wall lower parts 13, and a plurality of side wall upper parts located above the cavity lower part 10 a. 14 and a cavity upper part 10 b surrounded by 14. The cavity lower part 10a is a part in which the specimen is actually embedded in the paraffin block, that is, a part that forms a part to be sliced in the slicing step in the paraffin block described in the section of the prior art.
[0027]
In the embedding dish 1 according to the present embodiment, the shape of the paraffin block (see FIG. 1 (c)) after completion of the shaping / removal process described in the section of the prior art is completely shaved after the casting is finished. The cavity lower part 10a has a substantially prismatic shape (thin square plate shape) so that the cavity upper part 10b can be easily removed from the mold so that the cavity upper part 10b can be easily removed. It is trapezoidal.
[0028]
That is, the angle α formed by the inner surface of the bottom wall 11 (upper side surface in the figure) and the inner surface of the side wall lower portion 13 is set to 90 degrees or a value larger than 90 degrees and as close as possible to 90 degrees. In other words, the draft for removing the paraffin block from the cavity lower part 10a is set to 0 degree or a value larger than 0 degree and as close as possible to 0 degree. The angle α is most preferably 90 degrees (in fact, since the embedding dish 1 itself is flexible, if the embedding dish 1 is formed as shown in the drawing, the angle α is 90 degrees. It is possible to remove the block from the embedding dish 1). However, since the embedding dish 1 is manufactured by a resin injection molding method, the angle α corresponds to the minimum draft required for removing the embedding dish 1 from the embedding dish 1 mold. In actual products, it is set to around 5 degrees. Considering the above points, it is preferable to set the angle α to a value as small as possible in the range of 90 to 96 degrees according to the method of manufacturing the embedding dish 1.
[0029]
Further, the angle β formed by the inner surface of the bottom wall 11 (upper side surface in the figure) and the inner surface of the side wall upper portion 14 is set to a value sufficiently larger than the angle α. The angle β can be any value as long as it allows the paraffin block to be easily extracted from the embedding dish 1, but in the illustrated embodiment, the angle β is set to about 120 degrees. Yes.
[0030]
As described above, the angle α formed by the side wall lower portion 13 and the bottom wall 11 is set small, and the angle β formed by the side wall upper portion 14 and the bottom wall 11 is set large, thereby reducing labor and shaping in the shaping / removing process. The conflicting requirement of easy removal can be satisfied.
[0031]
The height h of the cavity lower part 10a is preferably set to 1 to 3 mm. If the height h is smaller than 1 mm, it is difficult to ensure that the specimen is surely embedded in the region corresponding to the cavity lower part 10a. If the height h is larger than 3 mm, the paraffin block is removed when removing the mold. This is because it becomes difficult. The height h of the cavity lower part 10a is set to about 1/3 of the total height H of the cavity 10.
[0032]
The relationship between the angle α formed by the side wall lower portion 13 and the bottom wall 11 and the angle β formed by the side wall upper portion 14 and the bottom wall 11 is a relationship that holds for all of the plurality of side walls 12.
[0033]
Next, the thickness setting of each part of the embedding dish 1 is demonstrated with reference to FIG.
[0034]
The wall thickness t11 of the bottom wall 11 is set to a smaller value than the wall thicknesses t13, t14, t2 of other portions. Since the wall thickness t11 of the bottom wall 11 is a portion that contacts the cooling plate 140 in the casting process, it greatly affects the solidification process of paraffin. When the embedding dish 1 is a resin injection molded product, since the thermal conductivity of the bottom wall 11 is low (compared to the case where the embedding dish 1 is made of metal), the thickness t11 of the bottom wall 11 is If it is not sufficiently thin, the solidification rate of paraffin will be extremely slow. As a result of the experiment, the inventor of the present application has found that the solidification rate of paraffin is sufficiently high in practice by setting the thickness t11 of the bottom wall 11 to 0.5 mm or less. It has also been found that when the thickness exceeds 0.5 mm, the solidification rate of paraffin becomes so slow that it becomes a practical problem. Therefore, the thickness t11 of the bottom wall 11 is set to 0.5 mm or less. Thus, by reducing the thickness t11 of the bottom wall 11, the molten paraffin poured into the cavity 10 is solidified with directivity from the portion in contact with the bottom wall 11 upward, Quality paraffin blocks can be obtained.
[0035]
On the other hand, the thickness of the other part of the embedding dish 1 is relatively large in the range of 0.6 to 1.0 mm. The reason is as follows.
[0036]
First, the reason why the side wall 12 is not made thin is that if the side wall 12 is made too thin, the side wall 12 remains stuck to the paraffin even if the embedding dish 1 is bent at the time of removing the mold (the relationship between the paraffin and the side wall 12). This is because removal of the mold becomes extremely difficult because air does not enter between them.
[0037]
The reason why the mounting wall 2 is not made thin is that the mounting wall 2 is given a relatively large heat capacity, and the molten paraffin that enters between the bottom wall of the cassette and the mounting wall 2 at the time of casting is quickly solidified. This is to make it happen. If the mounting wall 2 is made thin to reduce the heat capacity, molten paraffin that enters between the bottom wall of the cassette and the mounting wall 2 at the time of casting enters the edge wall 3 and then the unnecessary paraffin. A lot of man-hours are required to remove P2 (see FIG. 1).
[0038]
As described above, by reducing the thickness of the bottom wall 11 and relatively increasing the thickness of the other portions (side wall 12 and mounting wall 2), solidification and mold release with good balance during casting can be achieved. And the reduction of man-hours in the shaping / removing process, particularly the removing process.
[0039]
The thickness relationship between the bottom wall 11, the side wall 12, and the placement wall 2 is not limited to the bottom wall 11, the side wall 12, and the placement wall 2 shown in FIG. This is a relationship that holds for the mounting wall 2.
[0040]
It is known that the thickness t11 of the bottom wall 11 is preferably as thin as possible within the experimental range if only the solidification characteristics at the time of casting are taken into consideration when the embedding dish is resinous. However, if the thickness t11 of the bottom wall 11 is extremely reduced, the bottom wall 11 may be deformed when molten paraffin is poured and the temperature rises, and the production yield of the embedding dish 1 also decreases. To do. Therefore, the thickness t11 of the bottom wall 11 is preferably 0.2 mm or more. That is, the thickness t11 of the bottom wall 11 is suitably set to 0.2 to 0.5 mm, more preferably 0.3 to 0.4 mm.
[0041]
When the embedding dish 1 having the illustrated shape is integrally formed by the resin injection molding method, the fluidity is good in order to set the thickness t11 of the bottom wall 11 in the range of 0.2 to 0.5 mm as described above. It is necessary to use a resin material. The embedding dish 1 is also required to have chemical resistance and impact resistance. Furthermore, it is preferable that the embedding dish 1 is transparent so that it can be easily determined from the outside whether the casting of the paraffin is performed well and whether the solidification has been completed. In order to satisfy the above conditions, the embedding dish 1 is preferably formed of microcrystalline polyimide. When the embedding dish 1 was manufactured by using a normal crystalline resin injection molding method using microcrystalline polyimide, the wall thickness t11 of the bottom wall 11 could be reduced to about 0.4 mm.
[0042]
The wall thickness t11 of the bottom wall 11 can be reduced by improving the injection mold. For example, as schematically shown in FIG. 7, a slidable portion 31 a is provided in one mold 31 of the mold pair 30 for the embedding dish 1. Then, after the molten resin is injected between the molds 31 and 32 and the cavity 33 between the molds 31 and 32 is filled with the resin, the part 31 a is moved before the molten resin is solidified. A portion 33a corresponding to the bottom wall 11 of the filling plate 1 is narrowed. By manufacturing in this way, the wall thickness t11 of the bottom wall 11 can be made smaller than the limit wall thickness which can be manufactured by a normal injection molding method. In this case, the material of the embedding dish 1 can be other than the above-mentioned microcrystalline polyimide, but it is preferable to use microcrystalline polyimide.
[0043]
In the above description, the embedding dish 1 has been described on the assumption that it is integrally formed by a resin injection molding method. However, the present invention is not limited to this. The first characteristic portion of the above embodiment in which the upper part and the lower part of the cavity 10 have different shapes can be applied even when the embedding dish 1 is manufactured from a metal material such as stainless steel. The present invention can also be applied to vacuum forming using a resin film such as vinyl chloride as a raw material. Furthermore, you may implement | achieve the 1st characteristic part of the said embodiment by the additional process after the shaping | molding of the embedding dish 1 irrespective of the material of the embedding dish 1. FIG. Moreover, you may implement | achieve the 2nd characteristic of this embodiment which changes the thickness of the embedding dish 1 with a site | part by the additional process after the formation of the embedding dish 1 regardless of a material. However, in order to realize the first and second features at the lowest cost, it is preferable to integrally mold the embedding dish 1 by a resin injection molding method.
[0044]
In addition, the method of using the embedding dish 1 illustrated in FIGS. 2 to 6 is described with reference to FIG. 1 except that the shaping / removal process shown in FIG. 1 (c) is abolished or greatly reduced. This is the same as that described in the section of the prior art.
[0045]
【The invention's effect】
As described above, according to the present invention, it is possible to reduce the work man-hours and work time of the embedding process.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining each step of embedding processing.
FIG. 2 is a perspective view showing an embodiment of an embedding dish according to the present invention.
FIG. 3 is a view taken along the line III-III in FIG. 1 and showing only a main part appearing in a cross section.
4 is a view taken in the direction of arrows IV-IV in FIG. 1 and showing only the main part appearing in the cross section.
FIG. 5 is a plan view of the embedding dish shown in FIG. 1 as viewed from above.
6 is a plan view of the embedding dish shown in FIG. 1 as viewed from below. FIG.
7 is a cross-sectional view schematically showing a mold for forming the embedding dish shown in FIG. 1. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Embedment plate 2 Placement wall 10 Cavity 11 Bottom wall 12 Side wall 13 Side wall lower part 14 Side wall upper part 31a Mold slidable part S Sample P, P1 Casting material (paraffin)
h Cavity bottom height t11 Bottom wall thickness

Claims (2)

In embedding boat for carrying out the embedding process casting a material narrowing cast specimens,
Having a cavity into which the casting material is injected,
The cavity is defined by a bottom wall and a plurality of side walls provided upright at the periphery of the bottom wall;
The cavity has a cavity lower part on the bottom wall side and a cavity upper part located on the cavity lower part,
An angle α formed between an inner surface of a lower side wall of the side wall surrounding the lower portion of the cavity and an inner surface of the bottom wall is 90 to 96 degrees, and the upper side of the cavity of the side wall is surrounded. An embedding dish characterized by being smaller than an angle β formed by the inner surface of the upper side wall and the inner surface of the bottom wall. The embedding dish according to claim 1, wherein the lower part of the cavity has a prismatic shape or a truncated pyramid shape with a height of 1 to 3 mm .

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