Abstract: Cromoglycic acid derivatives of the general formula ##STR1## wherein R.sup.1 is an .alpha.-, .beta.- or .gamma.-amino acid residue (for ester bonding) whose amino group may optionally be substituted by at least one lower alkyl group, and R.sup.2 and R.sup.3 each independently is a lower alkyloxy-substituted or an unsubstituted lower alkyl group, an 1-alkanoyloxyalkyl group, an 1-alkoxycarbonyloxyalkyl group, a phthalidyl group or a 5-methyl-1,3-dioxol-2-on-4-ylmethyl group; nontoxic salts thereof; and pharmaceutical compositions containing such compounds. Since the compounds have antiallergic activity and are readily absorbable into the blood stream, they are useful as oral antiallergic agents.

Abstract: A surface treatment apparatus is composed of a supporting die for holding a substrate thereon to heat or cool the substrate; a cover capable of advancing close to the supporting die or into point-to-point contact with the supporting die to define a treatment space over the entire upper surface of the substrate on the supporting die, said cover defining a hole for the introduction of a surface treatment agent into the treatment space; and an evacuation chamber provided on the peripheral side wall of the supporting die, whereby the surface treatment agent is allowed to flow out from the treatment space into the evacuation chamber. No substantial conduction of heat takes place from the supporting die by way of the cover. The thermal distribution of the supporting die is thus kept extremely uniform, whereby each surface treatment can be conducted uniformly.

Abstract: In a method of surface treatment irradiating a part of a plate to be treated with light flux, detecting a quantity of transmitted light or reflected light on the plate corresponding to the light flux, detecting an end point of surface treatment based on the variation in the detected signal level the combination with the method of a step of detecting whether the detected signal level exceeds a predetermined target level within a predetermined period of time, a step of repeatedly setting up a new target level so long as the detected level is found exceeding the predetermined target level, and a step of determining the end point of the surface treatment at the moment when the detected signal level is found not exceeding the new target level.