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EP-4739764-A1 - CONTACT PLATE

EP4739764A1EP 4739764 A1EP4739764 A1EP 4739764A1EP-4739764-A1

Abstract

The invention relates to a contact plate comprising a dish (1) for receiving a nutrient medium, the dish having a base and an inner rim (2) delimiting the base. Furthermore, a lid (8) is provided which acts as an aerobic and/or anaerobic closure, can be slid over the inner rim (2) by means of a lid rim (9), and, optionally, can be locked with respect to the dish (1). The dish (1) has an outer rim (5) running coaxially around and at a distance from the inner rim (2), wherein an annular space (6) is formed between the inner rim (2) and the outer rim (5), which annular space is intended for inserting and optionally locking the lid rim (9), and wherein at least one groove (7) extending along at least portions of the circumference, or radially and/or axially oriented grooves, is/are formed on or in the base of the annular space (6), which groove(s) is/are intended for receiving a liquid, preferably in the form of condensation water, running over the inner rim (2) and/or the lid (8) and into the annular space (6).

Inventors

  • EIKMANNS, ULRICH
  • SCHINDLER, HEINZ

Assignees

  • Pharmamedia Dr. Mueller GmbH

Dates

Publication Date
20260513
Application Date
20250514

Claims (14)

  1. 1. Contact plate with a dish (1) for receiving a nutrient medium, the dish having a base and an inner rim (2) defining the base, and a lid (8) for aerobic and/or anaerobic closure, the lid being able to be placed over the inner rim (2) by means of a lid rim (9) and optionally locked against the dish (1), wherein the dish (1) has an outer rim (5) extending coaxially at a distance around the inner rim (2), wherein an annular space (6) is formed between the inner rim (2) and the outer rim (5), which serves for inserting and optionally locking the lid rim (9), and wherein at least one groove (7) or radially and/or axially oriented grooves are formed on or in the base of the annular space (6), which serve to receive a liquid, preferably in the form of condensation, flowing over the inner rim (2) and/or the lid (8) into the annular space (6).
  2. 2. Contact plate according to claim 1, characterized in that two or three grooves (7) are preferably formed coaxially to each other at or in the base of the annular space (6).
  3. 3. Contact plate according to claim 1 or 2, characterized in that the grooves (7) are continuous or interrupted in the circumferential direction.
  4. 4. Contact plate according to one of claims 1 to 3, characterized in that the grooves (7) are designed and dimensioned such that their walls or interfaces exert a capillary action on condensation water.
  5. 5. Contact plate according to claim 4, characterized in that the grooves (7) have an approximately rectangular cross-section with a groove depth and groove width in the range of 0.3 mm to 0.7 mm, preferably 0.5 mm, or which are semicircular in cross-section.
  6. 6. Contact plate according to one of claims 2 to 5, characterized in that the grooves (7) extend so deeply into the bottom of the annular space (6) that the latter is partially or completely reinforced on the downwardly directed outer side.
  7. 7. Contact plate according to one of claims 1 to 6, characterized in that the inner edge (2) has an inwardly directed, circumferential step at its upper free end.
  8. 8. Contact plate according to one of claims 1 to 7, characterized in that the inner rim (2) comprises, on the inside, retaining means for holding the nutrient medium (11) in the form of ridges, beads, etc.
  9. 9. Impression plate according to one of claims 1 to 8, characterized in that a circumferential step, a bead or the like is formed on the inner edge (2), in the area towards the bottom of the tray (1).
  10. 10. Contact plate according to one of claims 1 to 9, characterized in that the inner rim (2) has on its outer surface preferably orthogonal to the bottom of the tray thickenings, cams, ridges (13) or the like, which serve to position and/or clamp the lid.
  11. 11. Contact plate according to one of claims 1 to 10, characterized in that the outer edge extends from below the upper free end of the inner edge to below the bottom of the tray, so that the outer edge defines an annular base downwards.
  12. 12. Contact plate according to one of claims 1 to 11, characterized in that the outer rim (5) has an inner diameter which is larger than the outer diameter of the lid rim (9), so that it fits at least slightly over the lid (8) for stacking several contact plates.
  13. 13. Contact plate according to one of claims 1 to 12, characterized in that the edges (2, 5) taper in cross-section preferably conically towards their free ends.
  14. 14. Contact plate according to any one of claims 1 to 13, characterized in that the tray (1) and the lid (8) are made of injection-molded plastic. ```

Description

Tapping plate The invention relates to an impression plate with a dish for receiving a nutrient medium, having a base and an inner rim defining the base, and a lid for aerobic and/or anaerobic closure, which can be placed over the inner rim with a lid edge and optionally locked against the dish, wherein the dish has an outer rim extending coaxially at a distance around the inner rim, wherein an annular space is formed between the inner rim and the outer rim, which serves for inserting and optionally locking the lid edge. Contact plates are usually flat plastic trays filled with a sterile culture medium (e.g., Caso agar, malt extract agar, etc.). This culture medium is typically a microbiological medium used to detect microbial growth. The underside of the tray usually has a grid pattern, which makes counting the germs easier. Ready-to-use contact plates are known from practice, which include numerous formulations for surface monitoring, among other things in critical cleanrooms and isolators as well as in non-critical areas. Numerous contact plates are designed similarly to Petri dishes, namely as flat, round, and transparent dishes, with the lid regularly fitting into the area between an inner rim that defines the interior and an outer rim that defines the base. The nutrient medium inside is similar to a gelatinous mass and protrudes at least slightly beyond the inner rim, so that "contact plates" of any desired area are possible. When ready for use, both in the closed state (i.e., with the lid in place) and with the lid removed, there is a risk of condensation forming due to the dew point being reached. This causes the condensation to run down the sides of the contact plate, resulting in significant dampness on each contact plate, or in the case of stacked contact plates, particularly on surfaces. This creates the impression of an unclean or even unhygienic situation. Furthermore, this negatively impacts the handling of the contact plate. The present invention therefore aims to eliminate, as far as possible, the situation caused by the formation of condensation. Since it is impossible to prevent the formation of condensation when the dew point is reached, the situation concerning the contact plate should be optimized so that condensation does not play a disruptive role during the storage and/or handling of the contact plate. Furthermore, the contact plate according to the invention should differ from competing products. The aforementioned problem is solved by the features of claim 1. According to this claim, the generic contact plate comprises a very special design feature, namely the use of the annular space existing between the inner edge and the outer edge, which originally serves for the engagement of the lid and optionally for aerobic and/or anaerobic closure by means of a lid. The invention is based on a surprisingly simple yet highly effective idea, namely the use of capillary action or adhesive forces, by utilizing the annular space formed between the inner and outer edges not only to collect condensation but also to bind it permanently, in that at least one groove, at least partially circumferential, is formed on or in the base of the annular space. This groove serves to collect the liquid, preferably condensation, that flows into the annular space over the inner edge and/or the lid. It has been shown that the groove not only absorbs the liquid, but also retains it for a long time, namely due to capillary action. This demonstrates that- This indicates that the liquid that enters and is drawn into the groove does not escape onto the surface being sampled during the contact plate application, thus preventing contamination of the surface. On the contrary, once the liquid has entered the groove, it remains there, even when the contact plate is handled upside down and during the contact plate application itself. According to the invention, by providing the groove within the annular space, specifically at the bottom of the annular space, an effective measure for binding condensation or similar substances is created. Advantageously, several grooves can be provided on or in the base of the annular space, preferably arranged coaxially with each other. For example, it is conceivable to provide two or three grooves, which may be interrupted within themselves. In principle, it is conceivable that the grooves are coaxial with each other, optionally spaced at the same distance from one another. An interruption in the grooves may be caused by the presence of clamping or locking devices near the groove base to ensure the lid is securely held in place when inserted into the annular space between the inner and outer edges. Locking mechanisms may also be provided there to selectively achieve an aerobic and/or unaerobic closure of the contact plate. Specifically, it is conceivable that the grooves have an approximately rectangular cross-section. They can have a groove depth and width in the range of 0.3 mm to 0.7