First of all, congrats to the setter. It is not easy to set a thematic crossword in a symmetric grid but she has been doing it consistently. In each crossword brand names appear predominantly in gridfills and where they are not in the grid, the clueing takes care. The non-thematic entries are rare or non-existent. Cluewomanship is consistently good and disputations from the solver are negligible. The setter shows competence in writing deletion clues - I think I noticed three in this crossword and they are all done well. Sometimes in the def parts, some words are to be understood. E.g., 9ac. I think there are three or four such clues. I am not objecting to them but am merely giving pointers.
This blog has involved some work, but I did all the typing happily. But please excuse any errors/omissions. You are free to point them out.
As I said, it's not easy to include thematic words in grids.. While for general words we setters have resources with pattern search facility, autofind, etc, thematic words have to fall back on 'word lists'. Whether there is any for brand names, I don't know. So congrats to the setter once again.
Finally, my personal opinion is why should we give publicity to companies and brand names week after week, even if the publisher is a business paper. And does the setter have to resist pressures from any brandwallahs? Or do any companies bruit about their inclusion?
ACROSS
1. Vitamin equal essentially to Persian medicine - a drop inside that can be cleansing (9)
AQUAGARD (on edit)
AQUAGUARD
A (vitamin) QUA (eQUAl essentially) ... Sorry, I am yet to anno this clue fully - seeking reader help Def: 'that can be cleansing' _ For anno, see Comments
8. Exclaimed strangely losing calm, shocked by battery (5)
EXIDE
Anag of EXCLAIMED after deleting CALM - 'shocked' is anag ind - 'battery' is def
Because the letters to be deleted c a l m are not in the same lorder in the del fodder, the setter has used the anag signal 'strangely'
9. After two quarters loss, Akai gets right man, say for overseas communication (7)
AIRMAIL
A[ka]I R MAIL (~male) - def: "for overseas communication" OK - but can't we use this stamp for inland communication too?
Surface reading is done carefully
10. First things first, remember to immediately swallow glasses of juice (6)
FROOTI
Good surface reading - Anno needs a little thinking - OO (glasses - that is spectacles ) inserted in F R T I ( first letters of first ... immediately)
Wordplay handled competently
11. Bushman trails U-Haul, initially to church for a custom (6)
USANCE
I had to think hard for the anno - Def is 'custom' - CE is from 'church' - SAN 'Bushman' trails (comes after) U (U-Haul initially)
12. Void, once damaged appliances (8)
VIDEOCON
Anag of 'void once'; Anag signal: 'damaged'. Broad def in 'appliances'. I think that the first TV set that I owned was ECTV. This brand entered our home later.
15. Scatters RARE lens and picks up once more (8)
RELEARNS
Anag of 'rare lens' - 'picks up once more' is def.
Good anag fodder, good anag signal and good def.
Brand name in clue.
18. -50!!! Freezing..to live, gets hot stuff (6)
CHILIS
I had to think a little to get the anno - CHIL (deleting L from chill (freezing) - IS (?to live)
I am not sure if we can really get IS from live; for is it has to be 'lives'.
I like "-50!!! Freezing" for CHILL but the three EMs are rather too many. And for the minus sign, some special effort is needed to get it right but few subs are equal to it.
'Hot stuff' as def is acceptable, though the ans is in plural fform.
Also, as this word has many spelling variants, wordplay leads to the gridfill.
20. Child's play to reverse a car (6)
TOYOTA
Def is car - Word breakup is TOY (?child's play) TO (to reverse) A
Good surface reding but I am not sure if 'child's play' is OK for TOY. Toy is a plaything, not just 'play'. But I may be too persnickety.
During a visit of mine to the US, my granddaughter as a little child - not even a toddler - used to say TOYOTA whenever a car passed by on the highways (probably by looking at the insignia). When the song Bhagyadha was playing, she used to anticipate 'amma' and utter it.
21. State without English bike (7)
AVENGER
AVER (state) going around ENG (English) Def: bike
Could the State be UP, considering its leaders' aversion to English?!
22. Peak traffic finally to ease (5)
CREST
C (traffic finally) EASE (rest) - def: peak.
Good surface reading
23. Repossess brews, maybe from Starbucks ()
ESPRESSOS
Anag of 'repossess'
Good surface reading, good anag signal, also good def
Enu left out in interactive version
DOWN
2. Witticisms you exchanged last night get into one's ear (1-4)
Q-TIPS
Sub T (last night) for U (you) in QUIPS (witticisms) def: get into one's ears
Good surface reading.
Not sure if the letter sub is indicated correctly.
Some may not accept 'last night' as adequate ind for T
Def part handled well to gel with ther est of the clue..
3. Manic at core, chases power with designs in mind (6)
ARMANI
ANI (Manic at core) follows ARM (power)
Good surface reading
For def, do you have to reread the clue again? Or will '[one] with designs in mind' do?
4. You hear the Italian has no way around multinational (8)
UNILEVER
Def is multinational. U is from 'you hear' - The rest of anno is to be given by any reader.
5. A goal for students, to some extent (6)
DEGREE
DD
6. Wind down Cisco or reorganise (7)
SIROCCO
Def is 'wind'. Anag of 'Cisco or'. Brand in the clue.
7. Does cover logo for DKNY and Chanel, perhaps (9)
DESIGNERS
11. Stray hair I extracted in cooked cutlet by ready-mix maker (9)
ULTRATECH
Delete I from 'hair'. Put HRA in CUTLET and anagram the letters. Wordplay handled ably. Def is
'ready-mix maker' - that is 'concrete'.
13. Find CD above (8)
DISCOVER
'Find' is def. DISC (CD) OVER (above). Deleting Y from the TV channel name might have brought a brand in, perhaps.
14. Model goes after show with old flame and a bosom buddy (7)
PLAYTEX
PLAY (show) T (model) ex (old flame) - Def? 'bosom buddy'! - If you want, google for images. And quite honestly and really, I did and was caught out by Mrs. from behind. Had to explain!
Excellent surface reading.
16. Shrewd Tata's upset with a loss, take about-turn and note (6)
ASTUTE
AST (anag of Tatas after deleting a, plus U (?about-turn) TE (note)
Good surface reading.
While a regular setter might exploit 'statue' or 'staute' for wordplay, this brand setter must look for brands. And that is done well!
17. Big apple in cartons belongs to Roger or Stuart, perhaps (6)
BINNYS
NY (big apple) in BINS (cartons) Def: Roger or Stuart, perhaps. Textile/shipping company but defined thus. But then cricketers are now becoming brands!
19. New release from novice, trained at Italian company (5)
IVECO
'Trained' is anag signal. Anag of OVICE after deleting N from 'novice'. Def is Italian company. Good deletion ind. Good surface reading.